Despite discovery more than 100years ago and documented global occurrence from shallow waters to the deep sea, the life cycle of the enigmatic crustacean y-larvae isincompletely understood and adult forms remain unknown. To date, only 2 of the 17 formally described species, all based on larval stages, have been investigated using an integrative taxonomic approach. This approach provided descriptions of the morphology of the naupliar and cyprid stages, and made use of exuvial voucher material and DNA barcodes.
View Article and Find Full Text PDFFour new species of Paranaitis are described from estuarine and continental shelf bottoms from southern and southeastern Brazil: Paranaitis chitinosa sp. nov., P.
View Article and Find Full Text PDFAphroditiformia represents one of the most successful radiations of annelids, and is therefore an interesting model to understand morphological and functional evolution. Previous phylogenetic analyses yielded most families as monophyletic but excluded anchialine and interstitial species while failing to recover relationships within Sigalionidae. Here we address these shortcomings through the analysis of four molecular markers and 87 morphological characters sampled across 127 species under the assumptions of parsimony and model-based methods.
View Article and Find Full Text PDFsp. nov. is newly described based on specimens collected in Sagami Bay, Japan, at a depth of 150-250 m.
View Article and Find Full Text PDFAs 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.
View Article and Find Full Text PDFWe describe three new species of Eumida from shallow estuarine and shelf bottoms from south and southeastern Brazil as part of a regional survey of the family Phyllodocidae. Previous regional records of Eumida sanguinea (Örsted, 1843) are herein referred to Eumida dracodermica sp. nov.
View Article and Find Full Text PDFThe collecting trips by Ørsted and Kröyer in Central and South America resulted in a series of papers by Grube, the Annulata örstediana which contained the proposal for seven genera and descriptions for 84 species. There are some problems dealing with the correct number of contributions, their publication dates, the correct citation for the authors for each species name and sometimes even for the type locality. In order to improve the current situation, we have consulted the original publications together with the corresponding collections.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFThe nuchal organs of annelid Laonice bahusiensis (Spionidae) from northern Europe have been studied using scanning and transmission electron microscopy. L. bahusiensis is the first spionid species in which extensively developed, continuous nuchal organs are described.
View Article and Find Full Text PDFDetailed scanning electron microscopy of jaws within the genus Ophryotrocha (Dorvilleidae, Annelida) was performed on 871 jaw parts. The investigations resulted in new understandings of the ontogeny and jaw morphology and have systematic implications for the family. Five species in the genus (Ophryotrocha alborana, O.
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