Vrijenhoekia balaenophila gen. nov., sp. nov. (Polychaeta, Hesionidae) is described from a whale carcass at near 3000 m depth in Monterey Canyon off the coast of California. The phylogenetic relationships of V. balaenophila are assessed in a parsimony analysis of morphological data together with nucleotide data from 28S rDNA, 16S rDNA and cytochrome oxidase I genes. Within the hesionids V. balaenophila belongs to Psamathini, where it is the sister group to Sirsoe. Among psamathins it is morphologically distinguished by having six glandular lip pads around the mouth opening, papilla-shaped neuropodial lobes on segment 3, extreme length of the dorsal cirri, and by a characteristic growth pattern in which the maximum number of segments is already formed in subadults, and further growth takes place through size increase of the segments.
from morphology, 18S rDNA, 28S rDNA, 16S rDNA and COI. -Zoologica Scripta, 36, 99-107. We assess phylogenetic relationships within the polychaete family Hesionidae from morphological data combined with nucleotide data from 18S rDNA, 28S rDNA, 16S rDNA and COI. Parsimony and Bayesian analyses were performed on two data sets; the first was based on a more restricted set of terminals with both morphological and molecular data (17 ingroup terminals), while the second included additional taxa with morphological data only (25 ingroup terminals). The different sets of terminals yielded fully congruent results, as did the parsimony and the Bayesian analyses. Our results indicate high levels of homoplasy in traditionally used morphological characters in the group, and that Hesioninae, Gyptini and Gyptis are nonmonophyletic. Hesionini (mainly Hesione and Leocrates ), Psamathini (mainly Hesiospina , Micropodarke , Nereimyra , Psamathe and Syllidia ), Ophiodrominae (Gyptini and Ophiodromini) and Ophiodromini (mainly Heteropodarke , Ophiodromus and Podarkeopsis ) are monophyletic and agree with previous classifications, and Hesionini is probably the sister to all other hesionids. The placements of the small hesionids capricornia and Lizardia , the hydrothermal vent taxa Hesiodeira and Hesiolyra , and the newly described Hesiobranchia , remain uncertain. Christine Ruta, Muséum national d'Histoire naturelle, Département Systématique et Evolution,
Background How vascular systems and their respiratory pigments evolved is still debated. While many animals present a vascular system, hemoglobin exists as a blood pigment only in a few groups (vertebrates, annelids, a few arthropod and mollusk species). Hemoglobins are formed of globin sub-units, belonging to multigene families, in various multimeric assemblages. It was so far unclear whether hemoglobin families from different bilaterian groups had a common origin. Results To unravel globin evolution in bilaterians, we studied the marine annelid Platynereis dumerilii, a species with a slow evolving genome. Platynereis exhibits a closed vascular system filled with extracellular hemoglobin. Platynereis genome and transcriptomes reveal a family of 19 globins, nine of which are predicted to be extracellular. Extracellular globins are produced by specialized cells lining the vessels of the segmental appendages of the worm, serving as gills, and thus likely participate in the assembly of a previously characterized annelid-specific giant hemoglobin. Extracellular globin mRNAs are absent in smaller juveniles, accumulate considerably in growing and more active worms and peak in swarming adults, as the need for O2 culminates. Next, we conducted a metazoan-wide phylogenetic analysis of globins using data from complete genomes. We establish that five globin genes (stem globins) were present in the last common ancestor of bilaterians. Based on these results, we propose a new nomenclature of globins, with five clades. All five ancestral stem-globin clades are retained in some spiralians, while some clades disappeared early in deuterostome and ecdysozoan evolution. All known bilaterian blood globin families are grouped in a single clade (clade I) together with intracellular globins of bilaterians devoid of red blood. Conclusions We uncover a complex “pre-blood” evolution of globins, with an early gene radiation in ancestral bilaterians. Circulating hemoglobins in various bilaterian groups evolved convergently, presumably in correlation with animal size and activity. However, all hemoglobins derive from a clade I globin, or cytoglobin, probably involved in intracellular O2 transit and regulation. The annelid Platynereis is remarkable in having a large family of extracellular blood globins, while retaining all clades of ancestral bilaterian globins.
The family Oenonidae consists of Eunicida species with prionognath jaws. Its Australian fauna had been reported to comprise six species belonging to Arabella, Drilonereis, and Oenone. This study provides descriptions for four new species, redescriptions for three species (two previously recorded and a new record, Drilonereis cf. logani) and diagnoses for the genera recorded from Australia. Currently, eleven species of oenonids, distributed in three genera, are known for the Australian coast. On Lizard Island, this family shows low abundance (19 specimens collected) and high richness (seven species). Our results suggest that despite the increasing accumulation of information, the biodiversity of the family is still poorly estimated.
The polychaete fauna from the mangroves of the Amazon Coast in Maranhão state, Brazil, is reported in this study. Fourteen species are listed, namely Alitta succinea (Leuckart, 1847); Arabella (Arabella) iricolor Montagu, 1804; Capitella capitata (Fabricius, 1780) complex; Exogone (Exogone) breviantennata Hartmann-Schröder, 1959; Heteromastus filiformis (Claparède, 1864); Isolda pulchella Müller, 1858; Mediomastus californiensis Hartman, 1944; Namalycastis fauveli Nageswara Rao, 1981; Namalycastis geayi (Gravier, 1901); Namalycastis senegalensis (Saint-Joseph, 1901); Nephtys simoni Perkins, 1980; Paraonis amazonica sp. n.; Sigambra bassi (Hartman, 1945); and Sigambra grubii Müller, 1858. Among them, Namalycastis fauveli and Namalycastis geayi are recorded for the first time in Brazil. Paraonis amazonica sp. n. is a new species for science, characterized by a rounded prostomium, 4–8 pairs of foliaceous branchiae, absent eyes, and two types of modified neurochaetae, acicular and hook-shaped.
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