ArticleBiology letters2015
Cambrian stem-group annelids and a metameric origin of the annelid head.
Article in Biology letters, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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Who cites it
15 citing papers in PubMed.
- Polychaete annelids from the earliest Cambrian Period.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- An Increase in Animal Diversity was Facilitated by Ecologically-Driven Brain Complexity Throughout the Cambrian.BioEssays : news and reviews in molecular, cellular and developmental biology · 2026Review
- Article
- New fossil ofRoyal Society open science · 2024Article
- Annelids from the Cambrian (Wuliuan Stage, Miaolingian) Spence Shale Lagerstätte of northern Utah, USA.Historical biology · 2024Article
- First record of growth patterns in a Cambrian annelid.Royal Society open science · 2023Article
- Probability-based preservational variations within the early Cambrian Chengjiang biota (China).PeerJ · 2022Article
- Article
- Article
- Sclerite-bearing annelids from the lower Cambrian of South China.Scientific reports · 2019Article
- Ediacaran developmental biology.Biological reviews of the Cambridge Philosophical Society · 2018Article
- Article
- Earth's oldest 'Bobbit worm' - gigantism in a Devonian eunicidan polychaete.Scientific reports · 2017Article
- The impact of fossil data on annelid phylogeny inferred from discrete morphological characters.Proceedings. Biological sciences · 2016Article
- A new fireworm (Amphinomidae) from the Cretaceous of Lebanon identified from three-dimensionally preserved myoanatomy.BMC evolutionary biology · 2015Article
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3 authors.
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No grant is acknowledged in the PubMed record.
Abstract
The oldest fossil annelids come from the Early Cambrian Sirius Passet and Guanshan biotas and Middle Cambrian Burgess Shale. While these are among the best preserved polychaete fossils, their relationship to living taxa is contentious, having been interpreted either as members of extant clades or as a grade outside the crown group. New morphological observations from five Cambrian species include the oldest polychaete with head appendages, a new specimen of Pygocirrus from Sirius Passet, and an undescribed form from the Burgess Shale. We propose that the palps of Canadia are on an anterior segment bearing neuropodia and that the head of Phragmochaeta is formed of a segment bearing biramous parapodia and chaetae. The unusual anatomy of these taxa suggests that the head is not differentiated into a prostomium and peristomium, that palps are derived from a modified parapodium and that the annelid head was originally a parapodium-bearing segment. Canadia, Phragmochaeta and the Marble Canyon annelid share the presence of protective notochaetae, interpreted as a primitive character state subsequently lost in Pygocirrus and Burgessochaeta, in which the head is clearly differentiated from the trunk.
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