Early Cambrian sipunculan worms from southwest China
| Autor: | Jean Vannier, J. I. Saiz Salinas, Jun-Yuan Chen, Diying Huang |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
China
Golfingiidae Nematoda General Immunology and Microbiology biology Fossils Animal Structures General Medicine biology.organism_classification General Biochemistry Genetics and Molecular Biology Paleontology Extant taxon Phylogenetics GENERAL MORPHOLOGY Animals General Agricultural and Biological Sciences Phylogeny Research Article General Environmental Science Caudata |
| Zdroj: | Proceedings of the Royal Society of London. Series B: Biological Sciences. 271:1671-1676 |
| ISSN: | 1471-2954 0962-8452 |
| DOI: | 10.1098/rspb.2004.2774 |
| Popis: | We report the discovery of sipunculan worms from the Lower Cambrian Maotianshan Shale, near Kunming (southwest China). Their sipunculan identity is evidenced by the general morphology of the animals (sausage-shaped body with a slender retractable introvert and a wider trunk) and by other features, both external (e.g. perioral crown of tentacles, and hooks, papillae and wrinkle rings on the body surface) and internal (U-shaped gut, and the anus opening near the introvert-trunk junction). The three fossil forms (Archaeogolfingia caudata gen. et sp. nov., Cambrosipunculus tentaculatus gen. et sp. nov. and Cambrosipunculus sp.) have striking similarities to modern sipunculans, especially the Golfingiidae to which their evolutionary relationships are discussed. This study suggests that most typical features of extant sipunculans have undergone only limited changes since the Early Cambrian, thus indicating a possible evolutionary stasis over the past 520 Myr. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|