Nerida Wilson

Contrasting biogeographical patterns in Margarella (Gastropoda: Calliostomatidae: Margarellinae) across the Antarctic Polar Front

Publisher: Elsevier BV

Date: 03-2021

DOI: 10.1016/J.YMPEV.2020.107039

Australian Tropical Marine Micromolluscs: An Overwhelming Bias

Publisher: MDPI AG

Date: 02-08-2016

DOI: 10.3390/D8030017

Flexible colour patterns obscure identification and mimicry in Indo-Pacific Chromodoris nudibranchs (Gastropoda: Chromodorididae)

Publisher: Elsevier BV

Date: 07-2018

DOI: 10.1016/J.YMPEV.2018.02.008

Abstract: Chromodoris is a genus of colourful nudibranchs that feed on sponges and is found across the Indo-Pacific. While this was once the most erse chromodorid genus, recent work has shown that the genus should be restricted to a monophyletic lineage that contains only 22 species, all of which exhibit black pigmentation and planar spawning behaviour. Earlier phylogenies of this group are poorly resolved and thus additional work is needed to clarify species boundaries within Chromodoris. This study presents a maximum-likelihood phylogeny based on mitochondrial loci (COI, 16S) for 345 Chromodoris specimens, including data from 323 new specimens and 22 from GenBank, from across the Indo-Pacific. Species hypotheses and phylogenetic analysis uncovered 39 taxa in total containing 18 undescribed species, with only five of 39 taxa showing stable colour patterns and distinct morphotypes. This study also presents the first evidence for regional mimicry in this genus, with C. colemani and C. joshi displaying geographically-based variation in colour patterns which appear to match locally abundant congenerics, highlighting the flexibility of these colour patterns in Chromodoris nudibranchs. The current phylogeny contains short branch lengths, polytomies and poor support at interior nodes, which is indicative of a recent radiation. As such, future work will employ a transcriptome-based exon capture approach for resolving the phylogeny of this group. In all, this study included 21 of the 22 described species in the Chromodoris sensu stricto group with broad s ling coverage from across the Indo-Pacific, constituting the most comprehensive s ling of this group to date. This work highlights several cases of undocumented ersity, ultimately expanding our knowledge of species boundaries in this group, while also demonstrating the limitations of colour patterns for species identification in this genus.

Seven snail species hidden in one: Biogeographic diversity in an apparently widespread periwinkle in the Southern Ocean

Publisher: Wiley

Date: 06-07-2022

DOI: 10.1111/JBI.14453

Abstract: The Antarctic Circumpolar Current imparts significant structure to the Southern Ocean biota. The Antarctic Polar Front is a major barrier to dispersal, with separate species (or sometimes intraspecific clades) normally occurring either side of this feature. We examined the biogeographic structure of an apparent exception to this rule in a widespread genus of the Southern Ocean, the periwinkle snail, Laevilitorina. Southern Ocean. Littorinidae, Laevilitorininae, Laevilitorina . Using 750 specimens from 16 Southern Ocean Laevilitorina populations across km, we analysed mitochondrial COI and nuclear 28S sequences to uncover the evolutionary history of these marine near‐shore snails. We utilized multi‐locus phylogenetic reconstructions, species‐delimitation analyses, ergence‐time estimations and geometric morphometrics. Molecular data revealed that the widespread nominal species L. caliginosa comprises seven species‐level clades, all supported by morphological data, whereas the Antarctic nominal species L. antarctica , L. claviformis and L. umbilicata are conspecific. Six “ caliginosa ” clades are restricted to southern South America, but one lineage extends from Antarctica to distant sub‐Antarctic islands on both sides of the APF. Geometric morphometrics also identified significant differences among these clades, but uncoupled from genetic differentiation. The apparent trans‐APF distribution of the poorly dispersing Laevilitorina caliginosa is largely illusory: this taxon consists of at least seven discrete species, only one of which has a trans‐APF distribution. Similar to most Laevilitorina species, the remaining six “ caliginosa ” clades are narrow endemics. Biogeographical patterns in Laevilitorina reflect the role of vicariance associated with geological processes together with recent long‐distance dispersal events. Laevilitorina originated near the Eocene/Oligocene boundary and ersified during the Miocene and the Pliocene. Laevilitorina is not a cryptic‐species complex: speciation was accompanied by hitherto unrecognized morphological differentiation. This study represents the most detailed molecular work on Southern‐Ocean littorinids and reveals unforeseen ersity across this globally important region.

Host specificity versus plasticity: testing the morphology-based taxonomy of the endoparasitic copepod family Splanchnotrophidae with COI barcoding

Publisher: Cambridge University Press (CUP)

Date: 13-09-2016

DOI: 10.1017/S002531541600120X

Abstract: The Splanchnotrophidae is a family of highly modified endoparasitic copepods known to infest nudibranch or sacoglossan sea slug hosts. Most splanchnotrophid species appear to be specific to a single host, but some were reported from up to nine different host species. However, splanchnotrophid taxonomy thus far is based on external morphology, and taxonomic descriptions are, mostly, old and lack detail. They are usually based on few specimens, with intraspecific variability rarely reported. The present study used molecular data for the first time to test (1) the current taxonomic hypotheses, (2) the apparently strict host specificity of the genus Ismaila and (3) the low host specificity of the genus Splanchnotrophus with regard to the potential presence of cryptic species. Phylogenetic analyses herein used sequences of the barcoding region of the cytochrome oxidase I (COI) gene from 40 specimens representing 13 species of five genera. Species delimitation approaches include distance and barcoding gap analyses, haplotype networks and diagnostic nucleotides. Molecular results are largely compatible with the commonly accepted, morphology-based taxonomy of the Splanchnotrophidae. Strict host specificity could be confirmed for two Ismaila species. COI analyses also supported the idea that Splanchnotrophus angulatus is host-promiscuous. In Ismaila , morphology seems more suitable than barcoding to display speciation events via host switches in a recent Chilean radiation. In Splanchnotrophus , some genetic structure suggests ongoing ersification, which should be investigated further given the inadequate morphology-based taxonomy. The present study thus supports the presence of two different life history strategies in splanchnotrophids, which should be explored integratively.

Genomic insights of evolutionary divergence and life history innovations in Antarctic brittle stars

Publisher: Wiley

Date: 13-04-2023

DOI: 10.1111/MEC.16951

Abstract: Understanding the drivers of evolutionary innovation provides a crucial perspective of how evolutionary processes unfold across taxa and ecological systems. It has been hypothesised that the Southern Ocean provided ecological opportunities for novelty in the past. However, the drivers of innovation are challenging to pinpoint as the evolutionary genetics of Southern Ocean fauna are influenced by Quaternary glacial–interglacial cycles, oceanic currents and species ecology. Here we examined the genome‐wide single nucleotide polymorphisms of the Southern Ocean brittle stars Ophionotus victoriae (five arms, broadcaster) and O. hexactis (six arms, brooder). We found that O. victoriae and O. hexactis are closely‐related species with interspecific gene flow. During the late Pleistocene, O. victoriae likely persisted in a connected deep water refugium and in situ refugia on the Antarctic continental shelf and around Antarctic islands O. hexactis persisted exclusively within in situ island refugia. Within O. victoriae , contemporary gene flow linking to the Antarctic Circumpolar Current, regional gyres and other local oceanographic regimes was observed. Gene flow connecting West and East Antarctic islands near the Polar Front was also detected in O. hexactis . A strong association was detected between outlier loci and salinity in O. hexactis . Both O. victoriae and O. hexactis are associated with genome‐wide increase in alleles at intermediate‐frequencies the alleles associated with this peak appear to be species specific, and these intermediate‐frequency variants are far more excessive in O. hexactis . We hypothesise that the peak in alleles at intermediate frequencies could be related to adaptation in the recent past, linked to evolutionary innovations of increase in arm number and a switch to brooding from broadcasting, in O. hexactis .

Friomaramide, a Highly Modified Linear Hexapeptide from an Antarctic Sponge, Inhibits Plasmodium falciparum Liver-Stage Development

Publisher: American Chemical Society (ACS)

Date: 12-08-2019

DOI: 10.1021/ACS.JNATPROD.9B00362

Abstract: The cold waters of Antarctica are known to harbor a rich bio ersity. Our continuing interest in the chemical analysis of Antarctic invertebrates has resulted in the isolation of friomaramide (

Spawning and development in Osedax boneworms (Siboglinidae, Annelida)

Publisher: Springer Science and Business Media LLC

Date: 02-2009

DOI: 10.1007/S00227-008-1091-Z

An expert-driven framework for applying eDNA tools to improve biosecurity in the Antarctic

Publisher: Regional Euro-Asian Biological Invasions Centre Oy (REABIC)

Date: 2023

DOI: 10.3391/MBI.2023.14.3.01

Mimicry and mitonuclear discordance in nudibranchs: New insights from exon capture phylogenomics

Publisher: Wiley

Date: 17-09-2020

DOI: 10.1002/ECE3.6727

Abstract: Phylogenetic inference and species delimitation can be challenging in taxonomic groups that have recently radiated and where introgression produces conflicting gene trees, especially when species delimitation has traditionally relied on mitochondrial data and color pattern. Chromodoris , a genus of colorful and toxic nudibranch in the Indo‐Pacific, has been shown to have extraordinary cryptic ersity and mimicry, and has recently radiated, ultimately complicating species delimitation. In these cases, additional genome‐wide data can help improve phylogenetic resolution and provide important insights about evolutionary history. Here, we employ a transcriptome‐based exon capture approach to resolve Chromodoris phylogeny with data from 2,925 exons and 1,630 genes, derived from 15 nudibranch transcriptomes. We show that some previously identified mimics instead show mitonuclear discordance, likely deriving from introgression or mitochondrial capture, but we confirm one “pure” mimic in Western Australia. Sister–species relationships and species‐level entities were recovered with high support in both concatenated maximum likelihood (ML) and summary coalescent phylogenies, but the ML topologies were highly variable while the coalescent topologies were consistent across datasets. Our work also demonstrates the broad phylogenetic utility of 149 genes that were previously identified from eupulmonate gastropods. This study is one of the first to (a) demonstrate the efficacy of exon capture for recovering relationships among recently radiated invertebrate taxa, (b) employ genome‐wide nuclear markers to test mimicry hypotheses in nudibranchs and (c) provide evidence for introgression and mitochondrial capture in nudibranchs.

Using ultraconserved elements to track the influence of sea‐level change on leafy seadragon populations

Publisher: Wiley

Date: 09-12-2020

DOI: 10.1111/MEC.15744

Abstract: During the Last Glacial Maximum (LGM), global sea levels were 120–130 m lower than today, resulting in the emergence of most continental shelves and extirpation of subtidal organisms from these areas. During the interglacial periods, rapid inundation of shelf regions created a dynamic environment for coastal organisms, such as the charismatic leafy seadragon ( Phycodurus eques , Syngnathidae), a brooder with low dispersal ability inhabiting kelp beds in temperate Australia. Reconstructions of the palaeoshoreline revealed that the increase of shallow areas since the LGM was not uniform across the species' range and we investigated the effects of these asymmetries on genetic ersity and structuring. Using targeted capture of 857 variable ultraconserved elements (UCEs, 2,845 single nucleotide polymorphisms) in 68 in iduals, we found that the regionally different shelf topographies were paralleled by contrasting population genetic patterns. In the west, populations may not have persisted through sea‐level lows because shallow seabed was very limited. Shallow genetic structure, weak expansion signals and a westward cline in genetic ersity indicate a postglacial recolonization of the western part of the range from a more eastern location following sea‐level rise. In the east, shallow seabed persisted during the LGM and increased considerably after the flooding of large bays, which resulted in strong demographic expansions, deeper genetic structure and higher genetic ersity. This study suggests that postglacial flooding with rising sea levels produced locally variable signatures in colonizing populations.

Phylogenetic placement of the enigmatic worm-like Rhodopemorpha slugs as basal Heterobranchia

Publisher: Oxford University Press (OUP)

Date: 31-07-2017

DOI: 10.1093/MOLLUS/EYX031

Most Cephalaspidea have a shell, but transcriptomes can provide them with a backbone (Gastropoda: Heterobranchia)

Publisher: Elsevier BV

Date: 12-2020

DOI: 10.1016/J.YMPEV.2020.106943

Barcoding against a paradox? Combined molecular species delineations reveal multiple cryptic lineages in elusive meiofaunal sea slugs

Publisher: Springer Science and Business Media LLC

Date: 2012

DOI: 10.1186/1471-2148-12-245

COMPARATIVE SPERM ULTRASTRUCTURE IN FIVE GENERA OF THE NUDIBRANCH FAMILY CHROMODORIDIDAE (GASTROPODA: OPISTHOBRANCHIA)

Publisher: Oxford University Press (OUP)

Date: 05-2002

DOI: 10.1093/MOLLUS/68.2.133

Abstract: Sperm ultrastructure is examined in representatives of five genera of the nudibranch gastropod family Chromodorididae: (Chromodoris, Hypselodoris, Glossodoris, Risbecia and Pectenodoris) and the results compared with previous work on other gastropods, especially other nudibranchs. As chromodoridid phylogeny is still incompletely understood, this study partly focuses on the search for new and as yet untapped sources of informative characters. Like spermatozoa of most other heterobranch gastropods, those of the Chromodorididae are elongate, complex cells composed of an acrosomal complex (small, rounded acrosomal vesicle, and columnar acrosomal pedestal), a condensed nucleus, sub-nuclear ring, a highly modified mid-piece (axoneme + coarse fibres surrounded by a glycogen-containing, helically-coiled mitochondrial derivative) and terminally a glycogen piece (or homologue thereof). The finely striated acrosomal pedestal is a synapomorphy of all genera examined here, but interestingly also occurs in at least one dorid (Rostanga arbutus). Substantial and potentially taxonomically informative differences were also observed between genera in the morphology of the nucleus, the neck region of the mid-piece, and also the terminal glycogen piece. The subnuclear ring is shown for the first time to be a segmented, rather than a continuous structure similarly, the annular complex is shown to consist of two structures, the annulus proper and the herein-termed annular accessory body.

Resolving the taxonomy of the Antarctic feather star species complex Promachocrinus ‘kerguelensis’ (Echinodermata: Crinoidea)

Publisher: CSIRO Publishing

Date: 14-07-2023

DOI: 10.1071/IS22057

Abstract: An increasing number of Antarctic invertebrate taxa have been revealed as cryptic species complexes following DNA-based assessments. This ultimately necessitates a morphological reassessment to find traits that will help identify these cryptic or pseudocryptic species without the need for sequencing every in idual. This work concerns comatulid crinoid echinoderms long considered to represent a single, circum-Antarctic species, Promachocrinus kerguelensis. The first molecular studies sought to distinguish the ersity in the complex and understand the constituent species distributions but stopped short of formal taxonomic assessment. Here, we continued to increase s le representation around the Southern Ocean and sequenced the mitochondrial COI gene for all new specimens, and additional genes for a few representatives. We also elucidated previously unappreciated features, particularly body pigmentation and morphology of the centrodorsal ossicle in an attempt to diagnose some species morphologically and based on DNA data. The species complex within Promachocrinus is here resolved into P. kerguelensis Carpenter, 1879, P. vanhoeffenianus Minckert, 1905, P. joubini Vaney, 1910, P. mawsoni (Clark, 1937) comb. nov. (transferred from Florometra) and four previously unnamed species, P. fragarius sp. nov., P. unruhi sp. nov., P. uskglassi sp. nov. and P. wattsorum sp. nov. Although most species can be distinguished morphologically, several cannot be reliably separated without DNA data. All sequenced species are essentially circum-Antarctic, with the notable exception of P. wattsorum sp. nov. that is restricted to the Prince Edward Islands in the sub-Antarctic Indian Ocean and P. vanhoeffenianus that is only known from the type locality in the Davis Sea. The vast nature of the Antarctic and Southern Ocean ecosystem dictates large scale s ling to understand the full extent of the bio ersity. ZooBank: urn:lsid:zoobank.org:pub:F871CDC8-973B-48CE-8A61-33658D4EB4B1

The Chelidonura tsurugensis–sandrana (Gastropoda: Cephalaspidea) species complex: do reproductive decisions maintain colour polymorphism?

Publisher: Oxford University Press (OUP)

Date: 26-12-2011

DOI: 10.1093/MOLLUS/EYR057

Barriers to gene flow in common seadragons (Syngnathidae: Phyllopteryx taeniolatus)

Publisher: Springer Science and Business Media LLC

Date: 06-09-2016

DOI: 10.1007/S10592-016-0881-Y

Multiple Doris kerguelenensis (Nudibranchia) species span the Antarctic Polar Front

Publisher: Wiley

Date: 09-2022

DOI: 10.1002/ECE3.9333

Abstract: Despite strong historical biogeographical links between benthic faunal assemblages of the Magellan region of South America and the Antarctic Peninsula, very few studies have documented contemporary movement and gene flow in or out of the Southern Ocean, especially across the Antarctic Polar Front (APF). In fact, oceanographic barriers such as the APF and Antarctica's long geologic isolation have substantially separated the continents and facilitated the evolution of endemic marine taxa found within the Antarctic region. The Southern Ocean benthic sea slug complex, Doris “ kerguelenensis ,” are a group of direct‐developing, simultaneous hermaphrodites that lack a dispersive larval stage. To date, there are 59 highly ergent species known within this complex. Here, we provide evidence to show intraspecific genetic connectivity occurs across the APF for multiple species within the D. “ kerguelenensis ” nudibranch species complex. We addressed questions of genetic connectivity by examining the phylogeographic structure of the three best‐s led D. “ kerguelenensis ” species and another three trans‐APF species using the protein coding mtDNA gene, cytochrome oxidase I. We also highlight alternative refugia uses among species with the same life history traits (i.e., benthic and direct developers) and for some species, extremely large distributions are established (e.g., circumpolarity). By improving our s ling of these nudibranchs, we gain better insight into the population structure and connectivity of the Antarctic region. This work also demonstrates how difficult it is to make generalizations across Antarctic marine species, even among ecologically‐similar, closely related species.

A hybrid-capture approach to reconstruct the phylogeny of Scleractinia (Cnidaria: Hexacorallia)

Publisher: Elsevier BV

Date: 09-2023

DOI: 10.1016/J.YMPEV.2023.107867

Molecular phylogeny of extant Holothuroidea (Echinodermata)

Publisher: Elsevier BV

Date: 06-2017

DOI: 10.1016/J.YMPEV.2017.02.014

Abstract: Sea cucumbers (Holothuroidea) are a morphologically erse, ecologically important, and economically valued clade of echinoderms however, the understanding of the overall systematics of the group remains controversial. Here, we present a phylogeny of extant Holothuroidea assessed with maximum parsimony, maximum likelihood, and Bayesian approaches using approximately 4.3kb of mt- (COI, 16S, 12S) and nDNA (H3, 18S, 28S) sequences from 82 holothuroid terminals representing 23 of the 27 widely-accepted family-ranked taxa. Currently five holothuroid taxa of ordinal rank are accepted. We find that three of the five orders are non-monophyletic, and we revise the taxonomy of the groups accordingly. Apodida is sister to the rest of Holothuroidea, here considered Actinopoda. Within Actinopoda, Elasipodida in part is sister to the remaining Actinopoda. This latter clade, comprising holothuroids with respiratory trees, is now called Pneumonophora. The traditional Aspidochirotida is paraphyletic, with representatives from three orders (Molpadida, Dendrochirotida, and Elasipodida in part) nested within. Therefore, we discontinue the use of Aspidochirotida and instead erect Holothuriida as the sister group to the remaining Pneumonophora, here termed Neoholothuriida. We found four well-supported major clades in Neoholothuriida: Dendrochirotida, Molpadida and two new clades, Synallactida and Persiculida. The mapping of traditionally-used morphological characters in holothuroid systematics onto the phylogeny revealed marked homoplasy in most characters demonstrating that further taxonomic revision of Holothuroidea is required. Two time-tree analyses, one based on calibrations for uncontroversial crown group dates for Eleutherozoa, Echinozoa and Holothuroidea and another using these calibrations plus four more from within Holothuroidea, showed major discrepancies, suggesting that fossils of Holothuroidea may need reassessment in terms of placing these forms with existing crown clades.

Exploring the trends of adaptation and evolution of sclerites with regards to habitat depth in sea pens

Publisher: PeerJ

Date: 21-09-2022

DOI: 10.7717/PEERJ.13929

Abstract: Octocorals possess sclerites, small elements comprised of calcium carbonate (CaCO 3 ) that are important diagnostic characters in octocoral taxonomy. Among octocorals, sea pens comprise a unique order (Pennatulacea) that live in a wide range of depths. Habitat depth is considered to be important in the ersification of octocoral species, but a lack of information on sea pens has limited studies on their adaptation and evolution across depth. Here, we aimed to reveal trends of adaptation and evolution of sclerite shapes in sea pens with regards to habitat depth via phylogenetic analyses and ancestral reconstruction analyses. Colony form of sea pens is suggested to have undergone convergent evolution and the loss of axis has occurred independently across the evolution of sea pens. Divergences of sea pen taxa and of sclerite forms are suggested to depend on habitat depths. In addition, their sclerite forms may be related to evolutionary history of the sclerite and the surrounding chemical environment as well as water temperature. Three-flanged sclerites may possess the tolerance towards the environment of the deep sea, while plate sclerites are suggested to be adapted towards shallower waters, and have evolved independently multiple times. The common ancestor form of sea pens was predicted to be deep-sea and similar to family Pseudumbellulidae in form, possessing sclerites intermediate in form to those of alcyonaceans and modern sea pens such as spindles, rods with spines, and three-flanged sclerites with serrated edges sclerites, as well as having an axis and bilateral traits.

Bathyptilones: Terpenoids from an Antarctic Sea Pen, Anthoptilum grandiflorum (Verrill, 1879)

Publisher: MDPI AG

Date: 09-2019

DOI: 10.3390/MD17090513

Abstract: An Antarctic coral belonging to the order Pennatulacea, collected during the 2013 austral autumn by trawl from 662 to 944 m depth, has yielded three new briarane diterpenes, bathyptilone A-C (1–3) along with a trinorditerpene, enbepeanone A (4), which bears a new carbon skeleton. Structure elucidation was facilitated by one- and two-dimensional NMR spectroscopy, mass spectrometry and confirmed by X-ray crystallography. The three compounds were screened in four cancer cell lines. Bathyptilone A displayed selective nanomolar cytotoxicity against the neurogenic mammalian cell line Ntera-2.

Description of a new species of Bursatella Blainville, 1817 (Gastropoda, Aplysiida, Aplysiidae) from southern Australia

Publisher: Informa UK Limited

Date: 10-2020

DOI: 10.1080/13235818.2020.1837055

Phylogenomic analyses of deep gastropod relationships reject Orthogastropoda

Publisher: The Royal Society

Date: 07-11-2014

DOI: 10.1098/RSPB.2014.1739

Abstract: Gastropods are a highly erse clade of molluscs that includes many familiar animals, such as limpets, snails, slugs and sea slugs. It is one of the most abundant groups of animals in the sea and the only molluscan lineage that has successfully colonized land. Yet the relationships among and within its constituent clades have remained in flux for over a century of morphological, anatomical and molecular study. Here, we re-evaluate gastropod phylogenetic relationships by collecting new transcriptome data for 40 species and analysing them in combination with publicly available genomes and transcriptomes. Our datasets include all five main gastropod clades: Patellogastropoda, Vetigastropoda, Neritimorpha, Caenogastropoda and Heterobranchia. We use two different methods to assign orthology, subs le each of these matrices into three increasingly dense subsets, and analyse all six of these supermatrices with two different models of molecular evolution. All 12 analyses yield the same unrooted network connecting the five major gastropod lineages. This reduces deep gastropod phylogeny to three alternative rooting hypotheses. These results reject the prevalent hypothesis of gastropod phylogeny, Orthogastropoda. Our dated tree is congruent with a possible end-Permian recovery of some gastropod clades, namely Caenogastropoda and some Heterobranchia subclades.

Keikipukalides, Furanocembrane Diterpenes from the Antarctic Deep Sea Octocoral Plumarella delicatissima

Publisher: American Chemical Society (ACS)

Date: 20-12-2017

DOI: 10.1021/ACS.JNATPROD.7B00732

Chemistry and Bioactivity of the Deep-Water Antarctic Octocoral Alcyonium sp.

Publisher: MDPI AG

Date: 14-09-2022

DOI: 10.3390/MD20090576

Abstract: Chemical investigation of an Antarctic deep-water octocoral has led to the isolation of four new compounds, including three illudalane sesquiterpenoids (1–3) related to the alcyopterosins, a highly oxidized steroid, alcyosterone (5), and five known alcyopterosins (4, 6–9). The structures were established by extensive 1D and 2D NMR analyses, while 9 was verified by XRD. Alcyopterosins are unusual for their nitrate ester functionalization and have been characterized with cytotoxicity related to their DNA binding properties. Alcyopterosins V (3) and E (4) demonstrated single-digit micromolar activity against Clostridium difficile, an intestinal bacterium capable of causing severe diarrhea that is increasingly associated with drug resistance. Alcyosterone (5) and several alcyopterosins were similarly potent against the protist Leishmania donovani, the causative agent of leishmaniasis, a disfiguring disease that can be fatal if not treated. While the alcyopterosin family of sesquiterpenes is known for mild cytotoxicity, the observed activity against C. difficile and L. donovani is selective for the infectious agents.

Here be dragons - phylogeography ofPteraeolidia ianthina(Angas, 1864) reveals multiple species of photosynthetic nudibranchs (Aeolidina: Nudibranchia)

Publisher: Oxford University Press (OUP)

Date: 02-04-2015

DOI: 10.1111/ZOJ.12266

Detecting glacial refugia in the Southern Ocean

Publisher: Wiley

Date: 23-03-2020

DOI: 10.1111/ECOG.04951

Shagenes A and B, new tricyclic sesquiterpenes produced by an undescribed Antarctic octocoral

Publisher: American Chemical Society (ACS)

Date: 29-04-2014

DOI: 10.1021/OL500792X

Dating Antarctic ice sheet collapse: Proposing a molecular genetic approach

Publisher: Elsevier BV

Date: 2018

DOI: 10.1016/J.QUASCIREV.2017.11.014

Video surveys of sea snakes in the mesophotic zone shed light on trends in populations

Publisher: Frontiers Media SA

Date: 26-09-2022

DOI: 10.3389/FMARS.2022.921542

Abstract: Declines in abundance of sea snakes have been observed on reefs throughout the Indo-Pacific, although the reasons are unknown. To date, surveys have occurred on shallow reefs, despite sea snakes occurring over a large depth range. It is not known if populations of sea snakes in deep habitats have undergone similar declines. To address this, we analysed deep-water video data from a historical hotspot of sea snake ersity, Ashmore Reef, in 2004, 2016, and 2021. We collected 288 hours of video using baited remote underwater videos and a remotely operated vehicle at depths between 13 and 112 m. We observed 80 in iduals of seven species with Aipysurus laevis ( n = 30), Hydrophis peronii ( n = 8), and H. ocellatus ( n = 6) being the most abundant. Five of the species ( A. duboisii , A. apraefrontalis , H. ocellatus , H. kingii , and Emydocephalus orarius ) had not been reported in shallow waters for a decade prior to our study. We found no evidence of a decline in sea snakes across years in deep-water surveys, although abundances were lower than those in early shallow-water surveys. A comparison of BRUVS data from 2004 and 2016 was consistent with the hypothesis that predation by sharks may have contributed to the loss of sea snakes in shallow habitats. Our study highlights the use of underwater video to collect information on sea snakes in the mesophotic zone and also suggests that future monitoring should include these depths in order to capture a more complete representation of habitats occupied.

A Species Flock Driven by Predation? Secondary Metabolites Support Diversification of Slugs in Antarctica

Publisher: Public Library of Science (PLoS)

Date: 26-11-2013

DOI: 10.1371/JOURNAL.PONE.0080277

Patterns, processes and vulnerability of Southern Ocean benthos: a decadal leap in knowledge and understanding

Publisher: Springer Science and Business Media LLC

Date: 25-04-2013

DOI: 10.1007/S00227-013-2232-6

The Antarctic Circumpolar Current isolates and connects: Structured circumpolarity in the sea star Glabraster antarctica

Publisher: Wiley

Date: 12-10-2018

DOI: 10.1002/ECE3.4551

An ocean yet to be discovered: increasing systematic knowledge of Indo-Pacific

Publisher: CSIRO Publishing

Date: 23-09-2021

DOI: 10.1071/IS20088

Abstract: Numerous faunistic and ecological studies have been conducted throughout the Indo-Pacific Ocean to assess its bio ersity. Despite the abundance of research, studies on the species that inhabit the Indo-Pacific are still necessary due to its extent and high species richness. The major species richness of the genus Okenia Menke, 1830 (Nudibranchia, Goniodorididae) is found in the Indo-Pacific Ocean, including 38 of 60 valid species. Nevertheless, this number does not represent the real bio ersity, since at least 20 more species are already reported in field-guides as undescribed species belonging to this genus. The systematics of the genus Okenia are still unclear since it has been the subject of only a few and incomplete studies. In the present paper, we describe five new Okenia species from the coastlines of Japan, Mozambique and Australia: Okenia aurorapapillata sp. nov., Okenia elisae sp. nov., Okenia nakanoae sp. nov., Okenia siderata sp. nov. and Okenia tenuifibrata sp. nov. Moreover, anatomical details not previously described of Okenia atkinsonorum, Okenia barnardi, Okenia cf. echinata, Okenia hallucigenia, Okenia hiroi, Okenia japonica, Okenia pellucida, Okenia pilosa and Okenia rhinorma are provided. New partial sequences of standard markers (COI, 16S rRNA and H3) were obtained and a phylogenetic analysis that included all species with available data was performed. ZOOBANK urn:lsid:zoobank.org:pub:28AE2536-A264–4194–8AE3-C430620572E7

A review of extantTudivasumRosenberg & Petit, 1987 (Neogastropoda: Turbinellidae) and description of three new species from Western Australia

Publisher: Oxford University Press (OUP)

Date: 16-12-2020

DOI: 10.1093/MOLLUS/EYAA030

Abstract: Tu asum Rosenberg & Petit, 1987 is a morphologically distinct gastropod genus of low ersity. All but one species are known from Australia and they occur from the intertidal zone down to hundreds of metres on the continental shelf. These carnivorous gastropods are thought to have intracapsular development. The six currently recognized extant species are reviewed here and their geographical ranges clarified. Two new species, Tu asum chaneyi n. sp. and T. ashmorense n. sp., are described from Ashmore Reef, Western Australia, and are characterized by differences in protoconch colour and shell sculpture. The third new species, T. westrale n. sp., is described from the mid-west coast of Western Australia, where it has long been misidentified as T. spinosum (H. Adams & A. Adams, 1864). We generated a molecular phylogeny based on mitochondrial DNA sequence data to test morphological species concepts and reconstruct relationships among four of the described species. High levels of ergence within one of the new species could indicate an additional cryptic species.

A species complex within the red-reticulate Goniobranchus Pease, 1866 (Nudibranchia: Doridina: Chromodorididae)

Publisher: Springer Science and Business Media LLC

Date: 20-03-2020

DOI: 10.1007/S12526-020-01048-W

Distribution of Defensive Metabolites in Nudibranch Molluscs

Publisher: Springer Science and Business Media LLC

Date: 19-03-2018

DOI: 10.1007/S10886-018-0941-5

Abstract: Many plants and animals store toxic or unpalatable compounds in tissues that are easily encountered by predators during attack. Defensive compounds can be produced de novo, or obtained from dietary sources and stored directly without selection or modification, or can be selectively sequestered or biotransformed. Storage strategies should be optimized to produce effective defence mechanisms but also prevent autotoxicity of the host. Nudibranch molluscs utilize a erse range of chemical defences, and we investigated the accumulation and distribution of defensive secondary metabolites in body tissues of 19 species of Chromodorididae nudibranchs. We report different patterns of distribution across tissues, where: 1) the mantle had more or different (but structurally related) compounds than the viscera 2) all compounds in the mantle were also in the viscera and 3) the mantle had fewer compounds than the viscera. We found no further ex les of species that selectively store a single compound, previously reported in Chromodoris species. Consistent with other studies, we found high concentrations of metabolites in mantle rim tissues compared to the viscera. Using bioassays, compounds in the mantle were more toxic than compounds found in the viscera for Glossodoris vespa Rudman, 1990 and Ceratosoma brevicaudatum Abraham, 1876. In G. vespa, compounds in the mantle were also more unpalatable to palaemonid shrimp than compounds found in the viscera. This indicates that these species may modify compounds to increase bioactivity for defensive purposes and/or selectively store more toxic compounds. We highlight clear differences in the storage of sequestered chemical defences, which may have important implications for species to employ effective defences against a range of predators.

Evolutionary innovations in Antarctic brittle stars linked to glacial refugia

Publisher: Wiley

Date: 29-11-2021

DOI: 10.1002/ECE3.8376

Abstract: The drivers behind evolutionary innovations such as contrasting life histories and morphological change are central questions of evolutionary biology. However, the environmental and ecological contexts linked to evolutionary innovations are generally unclear. During the Pleistocene glacial cycles, grounded ice sheets expanded across the Southern Ocean continental shelf. Limited ice‐free areas remained, and fauna were isolated from other refugial populations. Survival in Southern Ocean refugia could present opportunities for ecological adaptation and evolutionary innovation. Here, we reconstructed the phylogeographic patterns of circum‐Antarctic brittle stars Ophionotus victoriae and O . hexactis with contrasting life histories (broadcasting vs brooding) and morphology (5 vs 6 arms). We examined the evolutionary relationship between the two species using cytochrome c oxidase subunit I (COI) data. COI data suggested that O . victoriae is a single species (rather than a species complex) and is closely related to O . hexactis (a separate species). Since their recent ergence in the mid‐Pleistocene, O . victoriae and O . hexactis likely persisted differently throughout glacial maxima, in deep‐sea and Antarctic island refugia, respectively. Genetic connectivity, within and between the Antarctic continental shelf and islands, was also observed and could be linked to the Antarctic Circumpolar Current and local oceanographic regimes. Signatures of a probable seascape corridor linking connectivity between the Scotia Sea and Prydz Bay are also highlighted. We suggest that survival in Antarctic island refugia was associated with increase in arm number and a switch from broadcast spawning to brooding in O . hexactis , and propose that it could be linked to environmental changes (such as salinity) associated with intensified interglacial‐glacial cycles.

3D microanatomy of a gastropod 'worm', Rhodope rousei n. sp. (Heterobranchia) from southern Australia

Publisher: Oxford University Press (OUP)

Date: 31-10-2011

DOI: 10.1093/MOLLUS/EYR028

Correction: Corrigendum: Resolving the evolutionary relationships of molluscs with phylogenomic tools

Publisher: Springer Science and Business Media LLC

Date: 28-11-2012

DOI: 10.1038/NATURE11736

Resolving the evolutionary relationships of molluscs with phylogenomic tools

Publisher: Springer Science and Business Media LLC

Date: 26-10-2011

DOI: 10.1038/NATURE10526

Abstract: Molluscs (snails, octopuses, clams and their relatives) have a great disparity of body plans and, among the animals, only arthropods surpass them in species number. This ersity has made Mollusca one of the best-studied groups of animals, yet their evolutionary relationships remain poorly resolved. Open questions have important implications for the origin of Mollusca and for morphological evolution within the group. These questions include whether the shell-less, vermiform aplacophoran molluscs erged before the origin of the shelled molluscs (Conchifera) or lost their shells secondarily. Monoplacophorans were not included in molecular studies until recently, when it was proposed that they constitute a clade named Serialia together with Polyplacophora (chitons), reflecting the serial repetition of body organs in both groups. Attempts to understand the early evolution of molluscs become even more complex when considering the large ersity of Cambrian fossils. These can have multiple dorsal shell plates and sclerites or can be shell-less but with a typical molluscan radula and serially repeated gills. To better resolve the relationships among molluscs, we generated transcriptome data for 15 species that, in combination with existing data, represent for the first time all major molluscan groups. We analysed multiple data sets containing up to 216,402 sites and 1,185 gene regions using multiple models and methods. Our results support the clade Aculifera, containing the three molluscan groups with spicules but without true shells, and they support the monophyly of Conchifera. Monoplacophora is not the sister group to other Conchifera but to Cephalopoda. Strong support is found for a clade that comprises Scaphopoda (tusk shells), Gastropoda and Bivalvia, with most analyses placing Scaphopoda and Gastropoda as sister groups. This well-resolved tree will constitute a framework for further studies of mollusc evolution, development and anatomy.

A biting commentary: Integrating tooth characters with molecular data doubles known species diversity in a lineage of sea slugs that consume “killer algae”

Publisher: Elsevier BV

Date: 09-2018

DOI: 10.1016/J.YMPEV.2018.02.027

Assessing the molluscan hypothesis Serialia (Monoplacophora+Polyplacophora) using novel molecular data

Publisher: Elsevier BV

Date: 2010

DOI: 10.1016/J.YMPEV.2009.07.028

Abstract: A consensus on molluscan relationships has yet to be achieved, largely because of conflicting morphological and molecular hypotheses. Monoplacophora show marked seriality of ctenidia, atria, muscles and nephridia and this has been interpreted as plesiomorphic for Mollusca, reflecting a segmented ancestry. More recently this seriality, also partly seen in Polyplacophora, has been seen as a derived condition. Analysis of the first published monoplacophoran DNA sequence from Laevilipilina antarctica Warén & Hain, 1992 [Giribet, G., Okusu, A., Lindgren, A.R., Huff, S., Schrödl, M., Nishiguchi, M.K., 2006. Evidence for a clade composed of molluscs with serially repeated structures: Monoplacophorans are related to chitons. Proc. Natl. Acad. Sci. USA 103, 7723-7728. 10.1073 nas.0602578103], showed Monoplacophora inside Polyplacophora. These taxa were then grouped under the name Serialia, reflecting the hypothesis that their seriality is a synapomorphy. Subsequent examination revealed that part of the L. antarctica published sequence was the result of contamination with Polyplacophora (Giribet, Supplementary Material S1). We collected and sequenced another monoplacophoran, Laevipilina hyalina McLean, 1979, resulting in the first multi-gene dataset representing all molluscan classes. Our analyses did not show unambiguous support for Serialia. Model-based approaches strongly supported Serialia as a clade, however, parsimony analyses under dynamic and static homology did not resolve the position of Monoplacophora. Although our study provides support for Serialia and none for Conchifera, it appears that further resolution of molluscan relationships will require large increases of data.

Emerging biological archives can reveal ecological and climatic change in Antarctica

Publisher: Wiley

Date: 08-09-2022

DOI: 10.1111/GCB.16356

Abstract: Anthropogenic climate change is causing observable changes in Antarctica and the Southern Ocean including increased air and ocean temperatures, glacial melt leading to sea‐level rise and a reduction in salinity, and changes to freshwater water availability on land. These changes impact local Antarctic ecosystems and the Earth's climate system. The Antarctic has experienced significant past environmental change, including cycles of glaciation over the Quaternary Period (the past ~2.6 million years). Understanding Antarctica's paleoecosystems, and the corresponding paleoenvironments and climates that have shaped them, provides insight into present day ecosystem change, and importantly, helps constrain model projections of future change. Biological archives such as extant moss beds and peat profiles, biological proxies in lake and marine sediments, vertebrate animal colonies, and extant terrestrial and benthic marine invertebrates, complement other Antarctic paleoclimate archives by recording the nature and rate of past ecological change, the paleoenvironmental drivers of that change, and constrain current ecosystem and climate models. These archives provide invaluable information about terrestrial ice‐free areas, a key location for Antarctic bio ersity, and the continental margin which is important for understanding ice sheet dynamics. Recent significant advances in analytical techniques (e.g., genomics, biogeochemical analyses) have led to new applications and greater power in elucidating the environmental records contained within biological archives. Paleoecological and paleoclimate discoveries derived from biological archives, and integration with existing data from other paleoclimate data sources, will significantly expand our understanding of past, present, and future ecological change, alongside climate change, in a unique, globally significant region.

Modern dynamics, morphology and habitats of slope-confined canyons on the northwest Australian margin

Publisher: Elsevier BV

Date: 2022

DOI: 10.1016/J.MARGEO.2021.106694

Polyphyly across oceans: a molecular phylogeny of the Chromodorididae (Mollusca, Nudibranchia)

Publisher: Wiley

Date: 30-10-2007

DOI: 10.1111/J.1463-6409.2007.00310.X

Comprehensive sampling reveals circumpolarity and sympatry in seven mitochondrial lineages of the Southern Ocean crinoid species Promachocrinus kerguelensis (Echinodermata)

Publisher: Wiley

Date: 31-03-2012

DOI: 10.1111/J.1365-294X.2012.05512.X

Erecting a new family for Spirostyliferina, a truncatelloidean microgastropod, and further insights into truncatelloidean phylogeny

Publisher: Wiley

Date: 06-10-2019

DOI: 10.1111/ZSC.12374

Basal chromodorid sperm ultrastructure (Nudibranchia, Gastropoda, Mollusca)

Publisher: Springer Science and Business Media LLC

Date: 12-04-2006

DOI: 10.1007/S00435-006-0017-X

A newly discovered radiation of endoparasitic gastropods and their coevolution with asteroid hosts in Antarctica

Publisher: Springer Science and Business Media LLC

Date: 18-09-2019

DOI: 10.1186/S12862-019-1499-8

Abstract: Marine invertebrates are abundant and erse on the continental shelf in Antarctica, but little is known about their parasitic counterparts. Endoparasites are especially understudied because they often possess highly modified body plans that pose problems for their identification. Asterophila , a genus of endoparasitic gastropod in the family Eulimidae, forms cysts in the arms and central discs of asteroid sea stars. There are currently four known species in this genus, one of which has been described from the Antarctic Peninsula ( A. perknasteri ). This study employs molecular and morphological data to investigate the ersity of Asterophila in Antarctica and explore cophylogenetic patterns between host and parasite. A maximum-likelihood phylogeny of Asterophila and subsequent species-delimitation analysis uncovered nine well-supported putative species, eight of which are new to science. Most Asterophila species were found on a single host species, but four species were found on multiple hosts from one or two closely related genera, showing phylogenetic conservatism of host use. Both distance-based and event-based cophylogenetic analyses uncovered a strong signal of coevolution in this system, but most associations were explained by non-cospeciation events. The prevalence of duplication and host-switching events in Asterophila and its asteroid hosts suggests that synchronous evolution may be rare even in obligate endoparasitic systems. The apparent restricted distribution of Asterophila from around the Scotia Arc may be an artefact of concentrated s ling in the area and a low obvious prevalence of infection. Given the richness of parasites on a global scale, their role in promoting host ersification, and the threat of their loss through coextinction, future work should continue to investigate parasite ersity and coevolution in vulnerable ecosystems.

One Antarctic slug to confuse them all: the underestimated diversity of

Publisher: CSIRO Publishing

Date: 06-2022

DOI: 10.1071/IS21073

Abstract: The Antarctic marine environment, although rich in life, is predicted to experience rapid and significant effects from climate change. Despite a revolution in the approaches used to document bio ersity, less than one percent of Antarctic marine invertebrates are represented by DNA barcodes and we are at risk of losing bio ersity before discovery. The ease of sequencing mitochondrial DNA barcodes has promoted this relatively ‘universal’ species identification system across most metazoan phyla and barcode datasets are currently readily used for exploring questions of species-level taxonomy. Here we present the most well-s led phylogeny of the direct-developing, Southern Ocean nudibranch mollusc, Doris kerguelenensis to date. This study s led over 1000 new Doris kerguelenensis specimens spanning the Southern Ocean and sequenced the mitochondrial COI gene. Results of a maximum likelihood phylogeny and multiple subsequent species delimitation analyses identified 27 new species in this complex (now 59 in total). Using rarefaction techniques, we infer more species are yet to be discovered. Some species were only collected from southern South America or the sub-Antarctic islands, while at least four species were found spanning the Polar Front. This is contrary to dispersal predictions for species without a larval stage such as Doris kerguelenensis. Our work demonstrates the value of increasing geographic scope in s ling and highlights what could be lost given the current global bio ersity crisis.

Surveying keratose sponges (Porifera, demospongiae, Dictyoceratida) reveals hidden diversity of host specialist barnacles (Crustacea, Cirripedia, Balanidae)

Publisher: Elsevier BV

Date: 08-2021

DOI: 10.1016/J.YMPEV.2021.107179

Crossing the polar front—Antarctic species discovery in the nudibranch genus Tritoniella (Gastropoda)

Publisher: Springer Science and Business Media LLC

Date: 26-01-2022

DOI: 10.1007/S13127-022-00541-3

Molecular Identification of Larvae of a Tetraphyllidean Tapeworm (Platyhelminthes: Eucestoda) in a Razor Clam as an Alternative Intermediate Host in the Life Cycle of Acanthobothrium brevissime

Publisher: American Society of Parasitologists

Date: 10-2009

DOI: 10.1645/GE-1946.1

Redescription of the Sea Hare Phyllaplysia viridis (Bergh, 1905) (Gastropoda: Heterobranchia: Aplysiida)

Publisher: Institute of Malacology

Date: 10-09-2020

DOI: 10.4002/040.063.0102

Clarifying the natural distribution of Saccostrea (edible rock oyster) species in Western Australia to guide development of a fledgling aquaculture industry

Publisher: Elsevier BV

Date: 03-2023

DOI: 10.1016/J.AQUACULTURE.2022.739202

Saved by the Shell: Molecular Analysis Detects the Cryptic Sea Hare, Aplysia concava G. B. Sowerby I, 1833 (Mollusca: Heterobranchia: Aplysiidae), from Oceania, with a Redescription

Publisher: MDPI AG

Date: 09-04-2021

DOI: 10.3390/TAXONOMY1020006

Abstract: A recent taxonomic revision split the circumglobal sea hare Aplysia parvula into 10 constituent taxa, of which only three are likely to be found in the Southern Pacific. This prompted an investigation of animals previously identified as A. parvula from Australia. Specimens collected from Eastern Australia and Hunter Island, east of New Caledonia, could not be satisfactorily identified with any of the currently accepted taxa based on morphological diagnostic features listed in the revision however, the presence of a highly concave shell is diagnostic. Quantification of genetic ergence using Cytochrome Oxidase I (COI) supports the delineation of this species as a distinct taxon, and a phylogenetic reconstruction based on concatenated COI, 16S and H3 markers reveals a sister relationship with the newly described Aplysia ghanimii from the Atlantic and Western Indian Oceans and an undescribed species from Japan. As a result, the name Aplysia concava G. B. Sowerby, I, 1833 is resurrected for this species. As the original description was based solely on a shell, a redescription is provided here with photographs of living animals and microscope images of internal anatomical structures.

Putting the ‘Indo’ back into the Indo-Pacific: resolving marine phylogeographic gaps

Publisher: CSIRO Publishing

Date: 2016

DOI: 10.1071/IS15032

Abstract: The Indo-Pacific is an extremely large marine realm that unites two oceans via a restricted Coral Triangle corridor, which was historically subjected to lowered sea levels during global glaciation. Although a strong phylogeographic focus on the Central and West Pacific has produced a large body of research, the Indian Ocean has been largely neglected. This may have serious consequences, because the Indian Ocean hosts a large number of marine centres of endemism, yet a large number of nations rely on its marine resources. We examine reasons for this neglect and review what is known about this region and its connectivity to the Indo-West Pacific. We draw attention to the ‘Leeuwin Effect’, a phenomenon where the southward flow of the Leeuwin Current is responsible for transporting larval propagules from the Coral Triangle region down the coast of Western Australia, resulting in broader Indo-West Pacific rather than Indian Ocean affinities. Given challenges in accessing infrastructure and s les, collaboration will inevitably be key to resolving data gaps. We challenge the assumption that the peak of shallow-water marine bio ersity is solely centred in the Coral Triangle, and raise awareness of a seemingly forgotten hypothesis promoting a secondary peak of bio ersity in the western Indian Ocean.

New deep-sea species of Xenoturbella and the position of Xenacoelomorpha

Publisher: Springer Science and Business Media LLC

Date: 03-02-2016

DOI: 10.1038/NATURE16545

Abstract: The discovery of four new Xenoturbella species from deep waters of the eastern Pacific Ocean is reported here. The genus and two nominal species were described from the west coast of Sweden, but their taxonomic placement remains unstable. Limited evidence placed Xenoturbella with molluscs, but the tissues can be contaminated with prey. They were then considered deuterostomes. Further taxon s ling and analysis have grouped Xenoturbella with acoelomorphs (=Xenacoelomorpha) as sister to all other Bilateria (=Nephrozoa), or placed Xenacoelomorpha inside Deuterostomia with Ambulacraria (Hemichordata + Echinodermata). Here we describe four new species of Xenoturbella and reassess those hypotheses. A large species (>20 cm long) was found at cold-water hydrocarbon seeps at 2,890 m depth in Monterey Canyon and at 1,722 m in the Gulf of California (Mexico). A second large species (~10 cm long) also occurred at 1,722 m in the Gulf of California. The third large species (~15 cm long) was found at ~3,700 m depth near a newly discovered carbonate-hosted hydrothermal vent in the Gulf of California. Finally, a small species (~2.5 cm long), found near a whale carcass at 631 m depth in Monterey Submarine Canyon (California), resembles the two nominal species from Sweden. Analysis of whole mitochondrial genomes places the three larger species as a sister clade to the smaller Atlantic and Pacific species. Phylogenomic analyses of transcriptomic sequences support placement of Xenacoelomorpha as sister to Nephrozoa or Protostomia.

A reply to Medina et al. (2011): Crawling through time: Transition of snails to slugs dating back to the Paleozoic based on mitochondrial phylogenomics

Publisher: Elsevier BV

Date: 12-2011

DOI: 10.1016/J.MARGEN.2011.07.003

Stabilizing selection on individual pattern elements of aposematic signals

Publisher: The Royal Society

Date: 23-08-2202

DOI: 10.1098/RSPB.2017.0926

Abstract: Warning signal variation is ubiquitous but paradoxical: low variability should aid recognition and learning by predators. However, spatial variability in the direction and strength of selection for in idual elements of the warning signal may allow phenotypic variation for some components, but not others. Variation in selection may occur if predators only learn particular colour pattern components rather than the entire signal. Here, we used a nudibranch mollusc, Goniobranchus splendidus , which exhibits a conspicuous red spot/white body/yellow rim colour pattern, to test this hypothesis. We first demonstrated that secondary metabolites stored within the nudibranch were unpalatable to a marine organism. Using pattern analysis, we demonstrated that the yellow rim remained invariable within and between populations however, red spots varied significantly in both colour and pattern. In behavioural experiments, a potential fish predator, Rhinecanthus aculeatus , used the presence of the yellow rims to recognize and avoid warning signals. Yellow rims remained stable in the presence of high genetic ergence among populations. We therefore suggest that how predators learn warning signals may cause stabilizing selection on in idual colour pattern elements, and will thus have important implications on the evolution of warning signals.

Genomic evidence for West Antarctic Ice Sheet collapse during the Last Interglacial Period

Publisher: Cold Spring Harbor Laboratory

Date: 31-01-2023

DOI: 10.1101/2023.01.29.525778

Abstract: The marine-based West Antarctic Ice Sheet (WAIS) is considered vulnerable to collapse under future climate trajectories and may even lie within the mitigated warming scenarios of 1.5–2 °C of the United Nations Paris Agreement. Knowledge of ice loss during similarly warm past climates, including the Last Interglacial period, when global sea levels were 5–10 m higher than today, and global average temperatures of 0.5–1.5 °C warmer, could resolve this uncertainty. Here we show, using a panel of genome-wide, single nucleotide polymorphisms of a circum-Antarctic octopus, persistent, historic signals of gene flow only possible with complete WAIS collapse. Our results provide the first empirical evidence that the tipping point of WAIS loss could be reached even under stringent climate mitigation scenarios. Historical gene flow in marine animals indicate the West Antarctic ice sheet collapsed during the Last Interglacial period.

Integrated evidence reveals a new species in the ancient blue coral genus Heliopora (Octocorallia)

Publisher: Springer Science and Business Media LLC

Date: 26-10-2018

DOI: 10.1038/S41598-018-32969-Z

Abstract: Maintaining the accretion potential and three dimensional structure of coral reefs is a priority but reef-building scleractinian corals are highly threatened and retreating. Hence future reefs are predicted to be dominated by non-constructional taxa. Since the Late Triassic however, other non-scleractinian anthozoans such as Heliopora have contributed to tropical and subtropical reef-building. Heliopora is an ancient and highly conserved reef building octocoral genus within the monospecific Family Helioporidae, represented by a single extant species – H . coerulea , Pallas, 1766. Here we show integrated morphological, genomic and reproductive evidence to substantiate the existence of a second species within the genus Heliopora . Importantly, some in iduals of the new species herein described as Heliopora hiberniana sp. nov. feature a white skeleton indicating that the most diagnostic and conserved Heliopora character (the blue skeleton) can be displaced. The new species is currently known only from offshore areas in north Western Australia, which is a part of the world where coral bleaching events have severely impacted the scleractinian community over the last two decades. Field observations indicate in iduals of both H . coerulea and H . hiberniana sp. nov. were intact after the 2016 Scott Reef thermal stress event, and we discuss the possibility that bleaching resistant non-scleractinian reef builders such as Heliopora could provide new ecological opportunities for the reconfiguration of future reefs by filling empty niches and functional roles left open by the regression of scleractinian corals.

A new genus with two new capitate species of dimorphic soft corals (Octocorallia : Alcyoniidae) from north-western Australia

Publisher: CSIRO Publishing

Date: 2019

DOI: 10.1071/IS17051

Abstract: Soft coral ersity in tropical northern Australia remains relatively understudied compared with other parts of the world. As a result of ongoing bio ersity surveys, we describe here a new genus of Octocorallia, Anastromvos, gen. nov., and two new species, A. aldersladei, sp. nov. and A. catherinae, sp. nov., collected from waters off the Pilbara, Kimberley and Darwin. To test the validity of the new genus, we used traditional morphological approaches combined with a molecular phylogeny using three mitochondrial genes (COI, mtMutS, ND2) and nuclear 28S. The markers did not lify for the colony of A. catherinae, sp. nov., which was described on the basis of morphology only. The new genus, belonging to the family Alcyoniidae, is dimorphic, possessing autozooids and siphonozooids, and is characterised by its unique capitate growth form, stone-like colony consistency, heavy autozooid polyp armature and the possession of clubs, tuberculated spindles and/or oval-shaped sclerites and crosses. The molecular phylogeny shows the new genus as the sister group to Sarcophyton+Lobophytum, and forms a unique clade among other alcyoniid clades. The Sarcophyton–Lobophytum group of taxa can be ecologically dominant in shallow-water coral reef communities but there is still much taxonomic refinement needed for these and related genera. rn:lsid:zoobank.org:pub:71E96A7A-A24D-4485-AF3B-834CEF959578

Molecular and morphological assessment of tropical sponges in the subfamily Phyllospongiinae, with the descriptions of two new species

Publisher: Oxford University Press (OUP)

Date: 24-11-2020

DOI: 10.1093/ZOOLINNEAN/ZLAA133

Abstract: Sponges in the subfamily Phyllospongiinae are important components of coral reefs. However, significant taxonomic inconsistencies exist in this group due to the lack of useful morphological characters for species delineation. This study assesses the systematics of some common phyllospongiinids in the genera Carteriospongia, Phyllospongia and Strepsichordaia from tropical Australia and the Red Sea, by using a multigene approach that utilizes the Internal Transcribed Spacer 2, the complete ribosomal 18S rRNA and three 28s rRNA gene regions (D1‒D2, D3‒D5 and D6‒D8), which produced a phylogenetic framework in which complementary morphological taxonomic assessments were performed. Type specimens were included, where available, and six species clades were recovered, including the well-established Phyllospongia papyracea and Strepsichordaia lendenfeldi. Carteriospongia foliascens, the type species for the genus Carteriospongia, is transferred to the genus Phyllospongia, resulting in Carteriospongia becoming a synonym of Phyllospongia. Consequently, Carteriospongia flabellifera is removed from Carteriospongia and is reinstated to its original designation of Polyfibrospongia flabellifera. Two new species, Phyllospongia bergquistae sp. nov. and Polyfibrospongia kulit sp. nov., are described. With phyllospongiinid sponges increasingly used as models for assessing the effects of climate change and anthropogenic stressors, this study provides a reliable systematics framework for the accurate identification of common phyllospongiinids across the Indo-Pacific.

A tropical Australian refuge for photosymbiotic benthic fauna

Publisher: Springer Science and Business Media LLC

Date: 16-05-2019

DOI: 10.1007/S00338-019-01809-5

Field collection of Laevipilina hyalina McLean, 1979 from southern California, the most accessible living monoplacophoran

Publisher: Oxford University Press (OUP)

Date: 30-01-2009

DOI: 10.1093/MOLLUS/EYP013

Ocean barriers and glaciation: evidence for explosive radiation of mitochondrial lineages in the Antarctic sea slug Doris kerguelenensis (Mollusca, Nudibranchia)

Publisher: Wiley

Date: 18-02-2009

DOI: 10.1111/J.1365-294X.2008.04071.X

Convergent camouflage and the non-monophyly of ‘seadragons’ (Syngnathidae: Teleostei): suggestions for a revised taxonomy of syngnathids

Publisher: Wiley

Date: 10-09-2010

DOI: 10.1111/J.1463-6409.2010.00449.X

Correction: Wilson, N.G., et al. Tropical Range Extension for the Temperate, Endemic South-Eastern Australian Nudibranch Goniobranchus splendidus (Angas, 1864). Diversity 2016, 8, 16

Publisher: MDPI AG

Date: 05-07-2018

DOI: 10.3390/D10030057

Diversity of Symbiodinium dinoflagellate symbionts from the Indo-Pacific sea slug Pteraeolidia ianthina (Gastropoda: Mollusca)

Publisher: Inter-Research Science Center

Date: 29-08-2006

DOI: 10.3354/MEPS320177

Phylogeography of recent Plesiastrea (Scleractinia: Plesiastreidae) based on an integrated taxonomic approach

Publisher: Elsevier BV

Date: 07-2022

DOI: 10.1016/J.YMPEV.2022.107469

Abstract: Scleractinian corals are a erse group of ecologically important yet highly threatened marine invertebrates, which can be challenging to identify to the species level. An influx of molecular studies has transformed scleractinian systematics, highlighting that cryptic species may be more common than previously understood. In this study, we test the hypothesis that Plesiastrea versipora (Lamarck, 1816), a species currently considered to occur throughout the Indo-Pacific in tropical, sub-tropical and temperate waters, is a single species. Molecular and morphological analyses were conducted on 80 s les collected from 31 sites spanning the majority of the species putative range and twelve mitogenomes were assembled to identify informative regions for phylogenetic reconstruction. Congruent genetic data across three gene regions supports the existence of two monophyletic clades aligning with distinct tropical and temperate provenances. Multivariate macromorphological analyses based on 13 corallite characters provided additional support for the phylogeographic split, with the number of septa and corallite density varying across this biogeographic ide. Furthermore, micromorphological and microstructural analyses identified that the temperate representatives typically develop sub-cerioid corallites with sparse or absent coenosteal features and smooth septal faces. In contrast, tropical representatives typically develop plocoid corallites separated by a porous dissepimental coenosteum and have granulated septal faces. These data suggest that at least two species exist within the genus PlesiastreaMilne Edwards & Haime, 1848. Based on examination of type material, we retain the name Plesiastrea versipora (Lamarck, 1816) for the temperate representatives of the genus and resurrect the name Plesiastrea peroniMilne Edwards & Haime, 1857 for the tropical members. This study highlights how broadly distributed hard coral taxa still need careful re-examination through an integrated systematics approach to better understand their phylogeographic patterns. Furthermore, it demonstrates the utility of integrating micro-, macro-morphological and genetic datasets, and the importance of type specimens when dealing with taxonomic revisions of scleractinian taxa.

Nudibranchs

Publisher: Elsevier BV

Date: 2018

DOI: 10.1016/J.CUB.2017.10.060

Abstract: Cheney and Wilson introduce nudibranchs, shell-less marine snails.

Phylotranscriptomics confirms Alveopora is sister to Montipora within the family Acroporidae

Publisher: Elsevier BV

Date: 04-2020

DOI: 10.1016/J.MARGEN.2019.100703

Abstract: The genus Alveopora is a scleractinian coral taxon whose phylogenetic classification has recently changed from the family Poritidae to Acroporidae. This change, which was made based on single-locus genetic data, has led to uncertainty about the placement of Alveopora and the ability for deep evolutionary relationships in these groups to be accurately recovered and represented by limited genetic datasets. We sought to characterize the higher-level position of Alveopora using newly available transcriptome data to confirm its placement within Acroporidae and resolve its closest ancestor. Here we present an analysis of a new 2031 gene dataset that confirms the placement of Alveopora within Acroporidae corroborating other single-locus (COI, 16S and ITS) analyses and a mitogenome dataset. We also resolve the position of Alveopora as sister to the genus Montipora. This has allowed the re-interpretation of morphology, and a rediagnosis of the family Acroporidae and the genus Alveopora.

Sperm ultrastructure of the Actinocyclidae (Mollusca, Nudibranchia) and homology of the terminal region of nudibranch sperm

Publisher: Informa UK Limited

Date: 2005

DOI: 10.1080/07924259.2005.9652141

The Florida amphioxus (Cephalochordata) hosts larvae of the tapeworm Acanthobothrium brevissime: natural history, anatomy and taxonomic identification of the parasite

Publisher: Wiley

Date: 27-11-2008

DOI: 10.1111/J.1463-6395.2008.00343.X

A new species of deep-sea Dendronotus Alder & Hancock (Mollusca:Nudibranchia) from California, with an expanded phylogeny of the genus

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/IS10027

Abstract: Dendronotus patricki, sp. nov. is a new species collected from a whalefall in the Monterey Canyon, California. This new species is characterised by having a small number of dorsal appendages compared with similarly sized species of Dendronotus Alder & Hancock, 1845. Anatomically, D. patricki, sp. nov. has a small prostate with just a few alveoli, a very small seminal receptacle situated near the distal end of the vagina, and a relatively short and small ulla. The rachidian radular teeth of D. patricki, sp. nov. are unique among Dendronotus as they have a well differentiated, conical cusp with very small denticles on either side, but most denticles are located on the sides of the teeth, rather than on the sides of the cusp. Dendronotus patricki, sp. nov., is genetically distinct from other species of Dendronotus for which sequence data are available. A phylogenetic analysis of Dendronotus based on COI, 16S, and H3 sequence data reveals that D. patricki, sp. nov. forms a polytomy with Dendronotus orientalis (Baba, 1932) and a clade of the shallow temperate and cold water species. The tropical Indo-Pacific species D. regius Pola & Stout, 2008 is the sister group to all other Dendronotus species.

Toxicity and taste: unequal chemical defences in a mimicry ring

Publisher: The Royal Society

Date: 06-06-2018

DOI: 10.1098/RSPB.2018.0457

Abstract: Mimicry of warning signals is common, and can be mutualistic when mimetic species harbour equal levels of defence (Müllerian), or parasitic when mimics are undefended but still gain protection from their resemblance to the model (Batesian). However, whether chemically defended mimics should be similar in terms of toxicity (i.e. causing damage to the consumer) and/or unpalatability (i.e. distasteful to consumer) is unclear and in many studies remains undifferentiated. In this study, we investigated the evolution of visual signals and chemical defences in a putative mimicry ring of nudibranch molluscs. First, we demonstrated that the appearance of a group of red spotted nudibranchs molluscs was similar from the perspective of potential fish predators using visual modelling and pattern analysis. Second, using phylogenetic reconstruction, we demonstrated that this colour pattern has evolved multiple times in distantly related in iduals. Third, we showed that these nudibranchs contained different chemical profiles used for defensive purposes. Finally, we demonstrated that although levels of distastefulness towards Palaemon shrimp remained relatively constant between species, toxicity levels towards brine shrimp varied significantly. We highlight the need to disentangle toxicity and taste when considering chemical defences in aposematic and mimetic species, and discuss the implications for aposematic and mimicry signal evolution.

Bioluminescent signals spatially amplified by wavelength-specific diffusion through the shell of a marine snail

Publisher: The Royal Society

Date: 15-12-2010

DOI: 10.1098/RSPB.2010.2203

Abstract: Some living organisms produce visible light (bioluminescence) for intra- or interspecific visual communication. Here, we describe a remarkable bioluminescent adaptation in the marine snail Hinea brasiliana . This species produces a luminous display in response to mechanical stimulation caused by encounters with other motile organisms. The light is produced from discrete areas on the snail's body beneath the snail's shell, and must thus overcome this structural barrier to be viewed by an external receiver. The diffusion and transmission efficiency of the shell is greater than a commercial diffuser reference material. Most strikingly, the shell, although opaque and pigmented, selectively diffuses the blue-green wavelength of the species bioluminescence. This diffusion generates a luminous display that is enlarged relative to the original light source. This unusual shell thus allows spatially lified outward transmission of light communication signals from the snail, while allowing the animal to remain safely inside its hard protective shell.

Cryptic species ofArchinome(Annelida: Amphinomida) from vents and seeps

Publisher: The Royal Society

Date: 07-11-2013

DOI: 10.1098/RSPB.2013.1876

Abstract: Since its description from the Galapagos Rift in the mid-1980s, Archinome rosacea has been recorded at hydrothermal vents in the Pacific, Atlantic and Indian Oceans. Only recently was a second species described from the Pacific Antarctic Ridge. We inferred the identities and evolutionary relationships of Archinome representatives s led from across the hydrothermal vent range of the genus, which is now extended to cold methane seeps. Species delimitation using mitochondrial cytochrome c oxidase subunit I (COI) recovered up to six lineages, whereas concatenated datasets (COI, 16S, 28S and ITS1) supported only four or five of these as clades. Morphological approaches alone were inconclusive to verify the identities of species owing to the lack of discrete diagnostic characters. We recognize five Archinome species, with three that are new to science. The new species, designated based on molecular evidence alone, include: Archinome levinae n. sp., which occurs at both vents and seeps in the east Pacific, Archinome tethyana n. sp., which inhabits Atlantic vents and Archinome jasoni n. sp., also present in the Atlantic, and whose distribution extends to the Indian and southwest Pacific Oceans. Biogeographic connections between vents and seeps are highlighted, as are potential evolutionary links among populations from vent fields located in the east Pacific and Atlantic Oceans, and Atlantic and Indian Oceans the latter presented for the first time.

Australindolones, New Aminopyrimidine Substituted Indolone Alkaloids from an Antarctic Tunicate Synoicum sp.

Publisher: MDPI AG

Date: 08-03-2022

DOI: 10.3390/MD20030196

Abstract: Five new alkaloids have been isolated from the lipophilic extract of the Antarctic tunicate Synoicum sp. Deep-sea specimens of Synoicum sp. were collected during a 2011 cruise of the R/V Nathanial B. Palmer to the southern Scotia Arc, Antarctica. Crude extracts from the invertebrates obtained during the cruise were screened in a zebrafish-based phenotypic assay. The Synoicum sp. extract induced embryonic dysmorphology characterized by axis truncation, leading to the isolation of aminopyrimidine substituted indolone (1–4) and indole (5–12) alkaloids. While the primary bioactivity tracked with previously reported meridianins A–G (5–11), further investigation resulted in the isolation and characterization of australindolones A–D (1–4) and the previously unreported meridianin H (12).

Range-wide population genomics of common seadragons shows secondary contact over a former barrier and insights on illegal capture

Publisher: Springer Science and Business Media LLC

Date: 29-05-2023

DOI: 10.1186/S12915-023-01628-9

Abstract: Common seadragons ( Phyllopteryx taeniolatus , Syngnathidae) are an emblem of the erse endemic fauna of Australia’s southern rocky reefs, the newly recognized “Great Southern Reef.” A lack of assessments spanning this global bio ersity hotspot in its entirety is currently h ering an understanding of the factors that have contributed to its ersity. The common seadragon has a wide range across Australia's entire temperate south and includes a geogenetic break over a former land bridge, which has called its status as a single species into question. As a popular aquarium display that sells for high prices, common seadragons are also vulnerable to illegal capture. Here, we provide range-wide nuclear sequences (986 variable Ultraconserved Elements) for 198 in iduals and mitochondrial genomes for 140 in iduals to assess species status, identify genetic units and their ersity, and trace the source of two poached in iduals. Using published data of the other two seadragon species, we found that lineages of common seadragons have erged relatively recently ( 0.63 Ma). Within common seadragons, we found pronounced genetic structure, falling into three major groups in the western, central, and eastern parts of the range. While populations across the Bassian Isthmus were ergent, there is also evidence for secondary contact since the passage opened. We found a strong cline of genetic ersity from the range center tapering symmetrically towards the range peripheries. Based on their genetic similarities, the poached in iduals were inferred to have originated from around Albany in southwestern Australia. We conclude that common seadragons constitute a single species with strong geographic structure but coherence through gene flow. The low genetic ersity on the east and west coasts is concerning given that these areas are projected to face fast climate change. Our results suggest that in addition to their life history, geological events and demographic expansions have all played a role in shaping populations in the temperate south. These insights are an important step towards understanding the historical determinants of the ersity of species endemic to the Great Southern Reef.

Fixed, free, and fixed: The fickle phylogeny of extant Crinoidea (Echinodermata) and their Permian–Triassic origin

Publisher: Elsevier BV

Date: 2013

DOI: 10.1016/J.YMPEV.2012.09.018

Abstract: Although the status of Crinoidea (sea lilies and featherstars) as sister group to all other living echinoderms is well-established, relationships among crinoids, particularly extant forms, are debated. All living species are currently placed in Articulata, which is generally accepted as the only crinoid group to survive the Permian-Triassic extinction event. Recent classifications have recognized five major extant taxa: Isocrinida, Hyocrinida, Bourgueticrinina, Comatulidina and Cyrtocrinida, plus several smaller groups with uncertain taxonomic status, e.g., Guillecrinus, Proisocrinus and Caledonicrinus. Here we infer the phylogeny of extant Crinoidea using three mitochondrial genes and two nuclear genes from 59 crinoid terminals that span the majority of extant crinoid ersity. Although there is poor support for some of the more basal nodes, and some tree topologies varied with the data used and mode of analysis, we obtain several robust results. Cyrtocrinida, Hyocrinida, Isocrinida are all recovered as clades, but two stalked crinoid groups, Bourgueticrinina and Guillecrinina, nest among the featherstars, lending support to an argument that they are paedomorphic forms. Hence, they are reduced to families within Comatulida. Proisocrinus is clearly shown to be part of Isocrinida, and Caledonicrinus may not be a bourgueticrinid. Among comatulids, tree topologies show little congruence with current taxonomy, indicating that much systematic revision is required. Relaxed molecular clock analyses with eight fossil calibration points recover Articulata with a median date to the most recent common ancestor at 231-252mya in the Middle to Upper Triassic. These analyses tend to support the hypothesis that the group is a radiation from a small clade that passed through the Permian-Triassic extinction event rather than several lineages that survived. Our tree topologies show various scenarios for the evolution of stalks and cirri in Articulata, so it is clear that further data and taxon s ling are needed to recover a more robust phylogeny of the group.

Multiple lineages and absence of panmixia in the “circumpolar” crinoid Promachocrinus kerguelensis from the Atlantic sector of Antarctica

Publisher: Springer Science and Business Media LLC

Date: 07-07-2007

DOI: 10.1007/S00227-007-0742-9

Population genetic structure of a broadcast-spawning coral across a tropical–temperate transition zone reveals regional differentiation and high-latitude reef isolation

Publisher: Wiley

Date: 08-11-2021

DOI: 10.1111/JBI.14280

Abstract: Genetic connectivity is a key component of species resilience to climate change in terms of recovery capacity following disturbance and capacity to disperse to novel locations as the climate warms and isotherms shift poleward. We aimed to strengthen our understanding of resilience in this context by characterizing patterns of connectivity and genetic ersity in a broadcast spawning coral across a tropical–temperate transition zone. We hypothesize genetic differentiation between tropical and temperate populations and decreasing genetic ersity with higher latitudes. Western Australia (WA). Turbinaria species complex. Turbinaria ‘reniformis’ Oken, 1815 (Scleractinia: Dendrophylliidae). A total of 930 target corals were s led from 10 locations between 13 and 32° latitude spanning a 9°C mean temperature range. In situ species identification of T . reniformis is hindered by morphological plasticity and homoplasy with sister species. We combined Sanger sequencing of two mitochondrial DNA markers and high‐throughput genotyping by sequencing (GBS) to isolate a single genetic Turbinaria lineage from our dataset through which patterns of genetic flow and ersity along the WA coastline could be explored using population‐ and in idual‐based clustering analyses. Mitochondrial DNA sequence variation was low among Turbinaria s les and could not resolve in idual species. Using GBS, we identified three genetically distinct lineages. Subsequent analyses within one of these lineages revealed strong spatial sub ision with 2–3 genetic clusters. While temperate populations were genetically erged from more tropical sites, we did not observe declines in genetic ersity with latitude. Tropical populations of T . ‘reniformis’ in Western Australia exhibit strong genetic connectivity, which extends to a southern limit at sub‐tropical Shark Bay. Temperate populations are genetically isolated from their tropical counterparts but have relatively high genetic ersity. While the maintenance of genetic variation in temperate populations may provide some resilience to future climate scenarios, their isolation may increase their vulnerability.

Reproductive variance in planar spawningChromodorisspecies (Mollusca: Nudibranchia)

Publisher: Informa UK Limited

Date: 11-2013

DOI: 10.1080/13235818.2013.801394

Molecular phylogeny of Chromodoris (Mollusca, Nudibranchia) and the identification of a planar spawning clade

Publisher: Elsevier BV

Date: 09-2005

DOI: 10.1016/J.YMPEV.2005.04.003

First Report of the Coral-Killing Sponge Terpios hoshinota Rützler and Muzik, 1993 in Western Australia: A New Threat to Kimberley Coral Reefs?

Publisher: MDPI AG

Date: 10-2019

DOI: 10.3390/D11100184

Abstract: The cyanobacteriosponge Terpios hoshinota has been reported throughout the Indo-Pacific including the Great Barrier Reef, Australia. The species encrusts live coral, giant clams, and other benthos and can be a threat to benthic communities on coral reefs. The Kimberley region of Western Australia has some of the least impacted reefs globally. We report for the first time the presence of T. hoshinota in the eastern Indian Ocean on Kimberley inshore coral reefs. Given its invasive potential, reef health surveys should include this species, and monitoring approaches developed to audit the remote Kimberley for this and other invasive species.

Site fidelity of mariametrid crinoids (Echinodermata: Crinoidea) in southeast Sulawesi, Indonesia

Publisher: Springer Science and Business Media LLC

Date: 13-01-2005

DOI: 10.1007/S00338-004-0435-5

An approach using ddRADseq and machine learning for understanding speciation in Antarctic Antarctophilinidae gastropods

Publisher: Springer Science and Business Media LLC

Date: 19-04-2021

DOI: 10.1038/S41598-021-87244-5

Abstract: S ling impediments and paucity of suitable material for molecular analyses have precluded the study of speciation and radiation of deep-sea species in Antarctica. We analyzed barcodes together with genome-wide single nucleotide polymorphisms obtained from double digestion restriction site-associated DNA sequencing (ddRADseq) for species in the family Antarctophilinidae. We also reevaluated the fossil record associated with this taxon to provide further insights into the origin of the group. Novel approaches to identify distinctive genetic lineages, including unsupervised machine learning variational autoencoder plots, were used to establish species hypothesis frameworks. In this sense, three undescribed species and a complex of cryptic species were identified, suggesting allopatric speciation connected to geographic or bathymetric isolation. We further observed that the shallow waters around the Scotia Arc and on the continental shelf in the Weddell Sea present high endemism and ersity. In contrast, likely due to the glacial pressure during the Cenozoic, a deep-sea group with fewer species emerged expanding over great areas in the South-Atlantic Antarctic Ridge. Our study agrees on how diachronic paleoclimatic and current environmental factors shaped Antarctic communities both at the shallow and deep-sea levels, promoting Antarctica as the center of origin for numerous taxa such as gastropod mollusks.

Due South: The evolutionary history of Sub-Antarctic and Antarctic Tritoniidae nudibranchs

Publisher: Elsevier BV

Date: 09-2021

DOI: 10.1016/J.YMPEV.2021.107209

CSIRO

Location: Australia

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Western Australian Museum

Location: Australia

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University Of Western Australia

Location: Australia

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Linkage Projects - Grant ID: LP160101508

Start Date: 11-2017

End Date: 10-2021

Amount: $221,973.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP190101347

Start Date: 2019

End Date: 12-2022

Amount: $285,000.00

Funder: Australian Research Council

Special Research Initiatives - Grant ID: SR200100005

Start Date: 06-2021

End Date: 06-2030

Amount: $36,000,000.00

Funder: Australian Research Council