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Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many have patterns of yellow, orange, red and green coloration. The foregut, stomach and intestine run a little below the midline of the body, the anus is at the tip of the tail, and the mouth is under the front. A little above the gut is the rhynchocoel, a cavity which mostly runs above the midline and ends a little short of the rear of the body. All species have a proboscis which lies in the rhynchocoel when inactive but everts to emerge just above the mouth to capture the animal's prey with venom. A highly extensible muscle in the back of the rhynchocoel pulls the proboscis in when an attack ends. A few species with stubby bodies filter feed and have suckers at the front and back ends, with which they attach to a host.
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Léon Louis Vaillant was a French zoologist. He is most famous for his work in the areas of herpetology, malacology, and ichthyology.
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Louisella is a genus of worm known from the Middle Cambrian Burgess Shale. It was originally described by Charles Walcott in 1911 as a holothurian echinoderm, and represents a senior synonym of Miskoia, which was originally described as an annelid. 48 specimens of Louisella are known from the Greater Phyllopod bed, where they comprise < 0.1% of the community. It has been stated to have palaeoscolecid-like sclerites, though this is not in fact the case.
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Le Règne Animal is the most famous work of the French naturalist Georges Cuvier. It sets out to describe the natural structure of the whole of the animal kingdom based on comparative anatomy, and its natural history. Cuvier divided the animals into four embranchements, namely vertebrates, molluscs, articulated animals, and zoophytes.
René-Édouard Claparède was a Swiss anatomist. The Claparède family was Protestant and originally from Languedoc. They moved to Geneva after Louis XIV:s Edict of Fontainebleau in 1685.
Pierre Louis André Fauvel was a French zoologist, who specialized in the study of polychaetes.
Fabriciidae is a family of annelid worm in the class Polychaeta.
Sedentaria is a diverse clade of annelid worms. It is traditionally treated as a subclass of the paraphyletic class Polychaeta, but it is also a monophyletic group uniting several polychaetes and the monophyletic class Clitellata. It is the sister group of Errantia.
References
- ↑ Banta, W.C.; Rice, M.E. (1970). "A restudy of the Middle Cambrian Burgess Shale fossil worm, Ottoia prolifica" (PDF). Proceedings of the International Symposium on the Biology of the Sipunculata and Echiura. 11.
- ↑ Annelida
- ↑ Armand de Quatrefages (1847). "Études sur les types inférieurs de l'embranchement des Annelés. Mémoire sur l'Échiure de Gaertner (Echiurus gaertnerii Nob.)". Annales des sciences naturelles . Series 3, Zoologie (in French). Paris: Crochard. 7: 307–343.
- ↑ Geoffrey Read (17 July 2017). "Gephyrea". WoRMS . Retrieved 7 March 2023.
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