New records of <i>Scolelepis</i> (Polychaeta : Spionidae) from the sandy beaches of Madagascar, with the description of a new species

Three species of the genus Scolelepis (Polychaeta, Spionidae) are reported from intertidal beaches in Madagascar. A new species, Scolelepis (Scolelepis) vazaha n.sp., is described from Cap Eat (type locality) and Fort Dauphin. This species is unique among spionids in possessing at least one large, curved hook in each notopodium of setiger 4. Males may additionally have similar hooks on setiger 5 or on setigers 5 and 6. On median setigers males also possess peculiar notopodial swellings, some of which contain a geniculate, penicillate seta of a type previously unknown for the family. S. (S.) williami (de Silva, 1961), formerly known only from the original description of two specimens from Sri Lanka, was found on five beaches along the southeast coast of Madagascar. This poorly known species is redescribed and compared to the closely related S. (S.) laciniata Eibye-Jacobsen, 1997, described from the west coast of Thailand. S. (S.) lefebvrei (Gravier, 1905), previously reported from the west coast of Madagascar, was also found on six sandy beaches along the northeast and southeast coasts. Earlier descriptions are supplemented by information on variation in numerical characters. Scanning electron photographs and details on palp morphology are provided for all three species

A new fireworm (Amphinomidae) from the Cretaceous of Lebanon identified from three-dimensionally preserved myoanatomy

© 2015 Parry et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article

A soft-bodied mollusc with radula from the Middle Cambrian Burgess Shale

Author Posting. © Nature Publishing Group, 2006. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature 442 (2006): 159-163, doi:10.1038/nature04894.Odontogriphus omalus was originally described as a problematic non-biomineralized lophophorate organism. Here we reinterpret Odontogriphus based on 189 new specimens including numerous exceptionally well-preserved individuals from the Burgess Shale collections of the Royal Ontario Museum. This additional material provides compelling evidence that the feeding apparatus in Odontogriphus is a radula of molluscan architecture comprising two primary bipartite tooth rows attached to a radular membrane and showing replacement by posterior addition. Further characters supporting molluscan affinity include a broad foot bordered by numerous ctenidia located in a mantle groove and a stiffened cuticular dorsum. Odontogriphus has a radula similar to Wiwaxia corrugata but lacks a scleritome. We interpret these animals to be members of an early stem-group mollusc lineage that likely originated in the Neoproterozoic Ediacaran Period, providing support for the retention of a biomat-based grazing community from the late Precambrian until at least the Middle Cambrian.Our research was in part supported by a Post-Doctoral Natural Sciences and Engineering Research Council of Canada grant (to JBC-2005) and by a Swedish Research Council grant (to CS)

An Early Cambrian stem polychaete with pygidial cirri

The oldest annelid fossils are polychaetes from the Cambrian Period. They are representatives of the annelid stem group and thus vital in any discussion of how we polarize the evolution of the crown group. Here, we describe a fossil polychaete from the Early Cambrian Sirius Passet fauna, Pygocirrus butyricampum gen. et sp. nov., with structures identified as pygidial cirri, which are recorded for the first time from Cambrian annelids. The body is slender and has biramous parapodia with chaetae organized in laterally oriented bundles. The presence of pygidial cirri is one of the characters that hitherto has defined the annelid crown group, which diversified during the Cambrian–Ordovician transition. The newly described fossil shows that this character had already developed within the total group by the Early Cambrian

The impact of fossil data on annelid phylogeny inferred from discrete morphological characters

As a result of their plastic body plan, the relationships of the annelid worms and even the taxonomic makeup of the phylum have long been contentious. Morphological cladistic analyses have typically recovered a monophyletic Polychaeta, with the simple-bodied forms assigned to an early-diverging clade or grade. This is in stark contrast to molecular trees, in which polychaetes are paraphyletic and include clitellates, echiurans and sipunculans. Cambrian stem group annelid body fossils are complex-bodied polychaetes that possess well-developed parapodia and paired head appendages (palps), suggesting that the root of annelids is misplaced in morphological trees. We present a reinvestigation of the morphology of key fossil taxa and include them in a comprehensive phylogenetic analysis of annelids. Analyses using probabilistic methods and both equal- and implied-weights parsimony recover paraphyletic polychaetes and support the conclusion that echiurans and clitellates are derived polychaetes. Morphological trees including fossils depict two main clades of crown-group annelids that are similar, but not identical, to Errantia and Sedentaria, the fundamental groupings in transcriptomic analyses. Removing fossils yields trees that are often less resolved and/or root the tree in greater conflict with molecular topologies. While there are many topological similarities between the analyses herein and recent phylogenomic hypotheses, differences include the exclusion of Sipuncula from Annelida and the taxa forming the deepest crown-group divergences

Chapitre IX. La dissidence des bons hommes

Le parcours doctrinal « des catharismes » de l’Occident chrétien a commencé par la Rhénanie et s’est prolongé en Italie, terrain privilégié du processus de rationalisation qui conduit la dissidence. Il se poursuit maintenant en empruntant des chemins apparemment erratiques. En commençant par la troisième aire doctrinale bien constituée, le Languedoc. Car l’itinéraire choisi ici obéit moins à une sorte de hiérarchie dans l’importance respective des communautés, qu’à l’ordre imposé par les témo..

A Cambrian crown annelid reconciles phylogenomics and the fossil record

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability: All data analysed in this paper are available as part of the Article, Extended Data Figs. 1–8 or Supplementary Information. The nomenclatural acts in this publication have been registered at ZooBank (LSID: urn:lsid:zoobank.org:pub:5BC89E47-2955-4539-94FD-D400E8C947FB).Code availability: The phylogenetic dataset, and the commands and topological constraints necessary to run the MrBayes analyses, are included as NEXUS formatted files in the Supplementary Information.The phylum of annelids is one of the most disparate animal phyla and encompasses ambush predators, suspension feeders and terrestrial earthworms1. The early evolution of annelids remains obscure or controversial2,3, partly owing to discordance between molecular phylogenies and fossils2,4. Annelid fossils from the Cambrian period have morphologies that indicate epibenthic lifestyles, whereas phylogenomics recovers sessile, infaunal and tubicolous taxa as an early diverging grade5. Magelonidae and Oweniidae (Palaeoannelida1) are the sister group of all other annelids but contrast with Cambrian taxa in both lifestyle and gross morphology2,6. Here we describe a new fossil polychaete (bristle worm) from the early Cambrian Canglangpu formation7 that we name Dannychaeta tucolus, which is preserved within delicate, dwelling tubes that were originally organic. The head has a well-defined spade-shaped prostomium with elongated ventrolateral palps. The body has a wide, stout thorax and elongated abdomen with biramous parapodia with parapodial lamellae. This character combination is shared with extant Magelonidae, and phylogenetic analyses recover Dannychaeta within Palaeoannelida. To our knowledge, Dannychaeta is the oldest polychaete that unambiguously belongs to crown annelids, providing a constraint on the tempo of annelid evolution and revealing unrecognized ecological and morphological diversity in ancient annelids.NSFCYunnan Provincial grantYIBS Donolley Postdoctoral FellowshipKey Research Program of the Institute of Geology and Geophysics, Chinese Academy of SciencesNatural Environment Research Council (NERC