To re-evaluate the relationships of the major bivalve lineages, we amassed detailed morpho-anatomical, ultrastructural and molecular sequence data for a targeted selection of exemplar bivalves spanning the phylogenetic diversity of the class. We included molecular data for 103 bivalve species (up to five markers) and also analysed a subset of taxa with four additional nuclear protein-encoding genes. Novel as well as historically employed morphological characters were explored, and we systematically disassembled widely used descriptors such as gill and stomach ‘types’. Phylogenetic analyses, conducted using parsimony direct optimisation and probabilistic methods on static alignments (maximum likelihood and Bayesian inference) of the molecular data, both alone and in combination with morphological characters, offer a robust test of bivalve relationships. A calibrated phylogeny also provided insights into the tempo of bivalve evolution. Finally, an analysis of the informativeness of morphological characters showed that sperm ultrastructure characters are among the best morphological features to diagnose bivalve clades, followed by characters of the shell, including its microstructure. Our study found support for monophyly of most broadly recognised higher bivalve taxa, although support was not uniform for Protobranchia. However, monophyly of the bivalves with protobranchiate gills was the best-supported hypothesis with incremental morphological and/or molecular sequence data. Autobranchia, Pteriomorphia, Heteroconchia, Palaeoheterodonta, Archiheterodonta, Euheterodonta, Anomalodesmata and Imparidentia new clade ( = Euheterodonta excluding Anomalodesmata) were recovered across analyses, irrespective of data treatment or analytical framework. Another clade supported by our analyses but not formally recognised in the literature includes Palaeoheterodonta and Archiheterodonta, which emerged under multiple analytical conditions. The origin and diversification of each of these major clades is Cambrian or Ordovician, except for Archiheterodonta, which diverged from Palaeoheterodonta during the Cambrian, but diversified during the Mesozoic. Although the radiation of some lineages was shifted towards the Palaeozoic (Pteriomorphia, Anomalodesmata), or presented a gap between origin and diversification (Archiheterodonta, Unionida), Imparidentia showed steady diversification through the Palaeozoic and Mesozoic. Finally, a classification system with six major monophyletic lineages is proposed to comprise modern Bivalvia: Protobranchia, Pteriomorphia, Palaeoheterodonta, Archiheterodonta, Anomalodesmata and Imparidentia.

MAINBAZA

Deep-sea fishes have been poorly sampled globally, and overall knowledge of demersal fish distributions and the drivers of community composition and diversity remain limited. Here, we used nine comparable datasets with specieslevel identification of fishes from research surveys around the world to test the hypothesis that deep-sea demersal fish assemblage composition on seamounts is consistent between major oceans. Two levels of analysis were undertaken: the first combined all presence-absence data from a seamount, while a second more detailed analysis included catch weight data based on a smaller number of seamounts. Overall, there was a consistent separation of seamounts by region based on the compositions of their fish assemblages. New Zealand and SE Australian seamounts have a very similar ichthyofauna, which differs substantially from seamounts in the eastern South Pacific Ocean off Chile. In the North Atlantic, Bear Seamount appears to be distinct from all others, while seamount fish assemblages off Ireland, the Azores, and Faraday Seamount have some affinities. The Tasman Sea and New Caledonian seamounts show strong intra-regional variation. On an ocean basin scale we therefore reject the hypothesis that the composition of deep-sea demersal fish fauna is homogeneous globally. However, regional patterns of both species composition and relative abundance show some similarities between widely separated geographical locations, especially where orange roughy is a dominant species. Salinity was the main environmental factor identified in a multivariate analysis of environmental covariate data. This is likely to be a result of salinity being a key characteristic defining both Antarctic Intermediate Water and North Atlantic Deep Water, the water masses found over most seamounts examined in this study, and which may explain similarities between deep-sea fish assemblages.

HALIPRO 2

SANTO 2006

Four genera and seven species of trapeziid crabs are identified from recent collections taken in New Caledonia. Descriptions and illustrations are given for new species; Calocarcinus crosnieri and Tetraiia sanguineomaculata. New records are reported for Calocarcinus africanus, Quadrella maculosa and Trapezia guttata. Trapezia cymodoce and T. septata, identified by A. MILNE EDWARDS from New Caledonia under the wrong names, are commented upon.

CHALCAL 2, LAGON, MUSORSTOM 4, MUSORSTOM 5

The evolutionary relationships of the brachyuran crab superfamily Eriphioidea, commonly known as stone or rubble crabs, are examined. Analysis of three mitochondrial (12S, 16S and COI) and two nuclear loci (18S and Histone 3) was carried out for 51 taxa representing the Carpilioidea, Dairoidea, Eriphioidea, Goneplacoidea, Parthenopoidea, Pilumnoidea, Portunoidea, Pseudozioidea and Xanthoidea. Phylogenetic analyses of molecular data used three methods of inference that recovered similar topologies with minor differences. Maximum parsimony analysis of 20 morphological characters taken from first zoeas of 11 species yielded two equally parsimonious trees and generally supported the molecular analyses. None of the analyses recovered Eriphioidea as monophyletic, and each of the eriphioid families represented by two or more taxa was shown to be polyphyletic in both molecular and larval analyses. This study indicates that the present classification based on adult morphology is incongruent with phylogenetic relationships and that the diagnostic characters the result of convergence (particularly in feeding morphology) rather than shared ancestry.

AURORA 2007, PANGLAO 2004, PANGLAO 2005

Currently, 13 subfamilies are recognised in the brachyuran family Xanthidae: Actaeinae, Antrocarcininae, Chlorodiellinae, Cymoinae, Etisinae, Euxanthinae, Kraussiinae, Liomerinae, Polydectinae, Speocarcininae, Xanthinae, Zalasiinae and Zosiminae. This classification has been based on shared adult features like a transversely ovate carapace, well defined dorsal carapace regions, usually with lateral dentition, stout chelipeds and relatively short ambulatory legs. Such characters are now considered to be convergent. Consequently a number of higher xanthid taxa may be artifical and not monophyletic. A broad sample of 147 xanthid species representing 75 out of 124 genera from all 13 xanthid subfamilies were sampled in a multi-gene analysis. Four markers (three mitochondria] and one nuclear) were used and yielded a tree with ca. 30 xanthid clades. Monophyletic support was demonstrated for the Antrocarcininae (although substantially redefined), Cymoinae, and Polydectinae. Almost every other subfamily was para- or polyphyletic. Furthermore, the two other families of the Xanthoidea, Pseudorhombilidae and Panopeidae, were found nested within the Xanthidae. The molecular results were consistent with phylogenetic relationships implied by a suite of novel and/or neglected "ventral" adult characters including sternal characters, position of genital openings and morphology of the first zoea, instead of "dorsal" characters traditionally used to infer xanthid relationships. (C) 2011 Elsevier GmbH. All rights reserved.

AURORA 2007, PANGLAO 2004, PANGLAO 2005, SANTO 2006, SMCB

PANGLAO 2004

BIOPAPUA