We describe a new species of Loimia, from shallow waters off Northern Papua New Guinea and compare morphologically to other species recorded from the region and a key is provided. We provide a Maximum likelihood tree for species of Loimia for which we have data and it forms a distinct clade from other species. Finally, we discuss characters that we consider as useful specific characters in this large genus, which includes many poorly described species.

PAPUA NIUGINI

Echinoids are key components of modern marine ecosystems. Despite a remarkable fossil record, the emergence of their crown group is documented by few specimens of unclear affinities, rendering their early history uncertain. The origin of sand dollars, one of its most distinctive clades, is also unclear due to an unstable phylogenetic context. We employ 18 novel genomes and transcriptomes to build a phylogenomic dataset with a near-complete sampling of major lineages. With it, we revise the phylogeny and divergence times of echinoids, and place their history within the broader context of echinoderm evolution. We also introduce the concept of a chronospace – a multidimensional representation of node ages – and use it to explore methodological decisions involved in time calibrating phylogenies. We find the choice of clock model to have the strongest impact on divergence times, while the use of site-heterogeneous models and alternative node prior distributions show minimal effects. The choice of loci has an intermediate impact, affecting mostly deep Paleozoic nodes, for which clock-like genes recover dates more congruent with fossil evidence. Our results reveal that crown group echinoids originated in the Permian and diversified rapidly in the Triassic, despite the relative lack of fossil evidence for this early diversification. We also clarify the relationships between sand dollars and their close relatives and confidently date their origins to the Cretaceous, implying ghost ranges spanning approximately 50 million years, a remarkable discrepancy with their rich fossil record.

BIOMAGLO

Munidopsid squat lobsters are among the most abundant decapods at abyssal depths and the most diverse squat lobster group in the East Pacific region. During recent cruises along the East Pacific, many deep-sea squat lobsters were collected. Among these, we described five new munidopsid species supported both by morphological characters and molecular phylogenetics: Munidopsis girguisi sp. nov., M. nautilus sp. nov., M. testuda sp. nov., M. cortesi sp. nov. and M. hendrickxi sp. nov. We also report new records of several Munidopsis species across the East Pacific that increase the species distribution ranges. Here, we reconstructed the phylogenetic relationships of the East Pacific species in relation to other Galatheoidea using one nuclear and two mitochondrial gene fragment(s); we also performed single locus species delimitation analyses to explore the species status of various East Pacific munidopsid taxa. The new taxa were photographed, illustrated and imaged with micro-computed tomography. The phylogenetic results show that: (1) Janetogalathea californiensis, previously included in the family Galatheidae, nests within Munidopsidae; (2) the phylogenetic position of Phylladiorhynchus and Coralliogalathea as belonging in Galatheidae is not supported; and (3) Munidopsis is paraphyletic, agreeing with recent systematic hypotheses. Short genetic distances and species delimitation analyses suggested that a clade mostly constituted by abyssal species might include fewer species than currently considered, as species show a wider geographic range than previously considered, conforming with traditional hypotheses of cosmopolitanisms in abyssal species.

BIOMAGLO, GUYANE 2014, HALIPRO 2, KANACONO, KARUBAR, KARUBENTHOS 2, KAVIENG 2014, MADEEP, MUSORSTOM 9, NORFOLK 2, TARASOC

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 diversity. 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 231–252 mya 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 sampling are needed to recover a more robust phylogeny of the group.

BORDAU 2, KARUBAR, SMIB 3

PAPUA NIUGINI

Comatulidae Fleming, 1828 (previously, and incorrectly, Comasteridae A.H. Clark, 1908a), is a group of feather star crinoids currently divided into four accepted subfamilies, 21 genera and approximately 95 nominal species. Comatulidae is the most commonly-encountered and species-rich crinoid group on shallow tropical coral reefs, particularly in the Indo-western Pacific region (IWP). We conducted a molecular phylogenetic analysis of the group with concatenated data from up to seven genes for 43 nominal species spanning 17 genera and all subfamilies. Basal nodes returned low support, but maximum likelihood, maximum parsimony, and Bayesian analyses were largely congruent, permitting an evaluation of current taxonomy and analysis of morphological character transformations. Two of the four current subfamilies were paraphyletic, whereas 15 of the 17 included genera returned as monophyletic. We provide a new classification with two subfamilies, Comatulinae and Comatellinae n. subfamily Summers, Messing, & Rouse, the former containing five tribes. We revised membership of analyzed genera to make them all clades and erected Anneissia n. gen. Summers, Messing, & Rouse. Transformation analyses for morphological features generally used in feather star classification (e.g., ray branching patterns, articulations) and those specifically for Comatulidae (e.g., comb pinnule form, mouth placement) were labile with considerable homoplasy. These traditional characters, in combination, allow for generic diagnoses, but in most cases we did not recover apomorphies for subfamilies, tribes, and genera. New morphological characters that will be informative for crinoid taxonomy and identification are still needed. DNA sequence data currently provides the most reliable method of identification to the species-level for many taxa of Comatulidae.

PAPUA NIUGINI, SALOMON 2

An efficient protocol to identify and describe species of Myzostomida is outlined and demonstrated. This taxonomic approach relies on careful identification (facilitated by an included comprehensive table of available names with relevant geographical and host information) and concise descriptions combined with DNA sequencing, live photography, and accurate host identification. Twenty-one new species are described following these guidelines: Asteromyzostomum grygieri n. sp., Endomyzostoma scotia n. sp., Endomyzostoma neridae n. sp., Mesomyzostoma lanterbecqae n. sp., Hypomyzostoma jasoni n. sp., Hypomyzostoma jonathoni n. sp., Myzostoma debiae n. sp., Myzostoma eeckhauti n. sp., Myzostoma hollandi n. sp., Myzostoma indocuniculus n. sp., Myzostoma josefinae n. sp., Myzostoma kymae n. sp., Myzostoma laurenae n. sp., Myzostoma miki n. sp., Myzostoma pipkini n. sp., Myzostoma susanae n. sp., Myzostoma tertiusi n. sp., Protomyzostomum lingua n. sp., Protomyzostomum roseus n. sp., Pulvinomyzostomum inaki n. sp., and Pulvinomyzostomum messingi n. sp.

PAPUA NIUGINI

One of the most common genera of feather stars found on tropical Indo-western Pacific reefs, Himerometra A.H.Clark, 1907, has previously included six accepted species, distinguished chiefly by variations in the enlarged proximal pinnules. This study examined new and existing specimens using molecular (mtDNA and nuDNA) techniques and morphological characters to revise the genus. Both approaches support placing H. magnipinna and H. martensi as a junior synonyms of H. robustipinna. Sequence data for specimens attributed to H. bartschi also place this species as a junior synonym of H. robustipinna, despite some morphological disparity. Himerometra sol is retained as distinct despite morphological congruence with H. robustipinna, because the two known specimens were collected outside the known range of the latter, with no molecular data currently available. Himerometra persica is herein transferred to Heterometra: the type specimens were incorrectly identified. The species treated as valid are redescribed. This study illustrates the importance of re-examining crinoid species boundaries for established taxa without molecular corroboration and demonstrates that diversity in this particular feather star clade might be lower than previously thought.

PAPUA NIUGINI

The featherstar genera, Dichrometra A.H. Clark, 1909a, Lamprometra A.H. Clark, 1913, and Liparometra A.H. Clark, 1913 (Comatulida: Mariametridae), are currently diagnosed only on the basis of the relative lengths of their proximal three pairs of pinnules. Previous published descriptions and a morphological re-examination indicate that this character is inconsistent and phenotypically variable. Distinctions amongst most of the 11 currently recognized species within each of these three genera are similarly ambiguous. This study compared currently accepted diagnostic characters amongst members of these three genera and incorporated mitochondrial DNA and nuclear DNA sequencing to assess taxonomic distinctions. Specimens were obtained from throughout the range of all three genera. Molecular data supported a monophyletic grouping, which we have placed under the senior generic name Dichrometra, based on a level of intraspecies divergence similar to that in other featherstar taxa, with four distinct species-level clades: palmata Müller, 1841, flagellata Müller, 1841, gyges Bell, 1884, and brachypecha H.L. Clark, 1915, the latter two resurrected from synonymy under palmata. Amongst these, proportions of proximal pinnules contributed only to the diagnosis of D. brachypecha. These species and the genus are redescribed. However, new diagnostic morphological characters remain, because they are needed to corroborate the four clades distinguished by molecular data. Because no sequence data were available from specimens identifiable as the remaining nine nominal species, we maintain them as accepted, pending further information.

PAPUA NIUGINI

SANTO 2006