Family PROCHAETODERMATIDAE
Introduction
Species of Prochaetodermatidae are often a numerically dominant form in the deep sea with densities up to 400 per square metre in quantitative samples (Scheltema 1985, 1997). The family, belonging to the Chaetodermomorpha, is cosmopolitan and has been found at all depths from the upper continental slope to hadal depths greater than 8000 m (Belyaev 1989). The family comprises five genera and 24 named species, with distributions known from a number of unpublished species. Although Salvini-Plawen (1992) did not recognise Spathoderma Scheltema and Rhabdoderma Scheltema (= Claviderma Scheltema & Ivanov) as separate from Prochaetoderma Thiele, the synonymies are not justified (Ivanov & Scheltema 2000; Scheltema & Ivanov 2000), and Lonchoderma Salvini-Plawen is synonymous with Spathoderma. The genera Claviderma and Prochaetoderma occur on the continental slope off SE Australia (Scheltema 1989).
Prochaetodermatid species are recognised by their small size, less than 5 mm, a posterior tail-like body region, and the presence of a pair of large, chitinous jaws. Spicules have simple sculpturing; their shape and arrangement along the body are diagnostic at the genus level. The radula is small with several rows of teeth, each row with two teeth. With several rows of a single pair of teeth, this is the only family among Aplacophora that has the radula used for rasping (Scheltema 1981). Prochaetodermatids are omnivorous, feeding upon organic detritus and small organisms.
The only life history data known for any aplacophoran is for a single species of Prochaetoderma (Scheltema 1987). Individuals settled into experimental recruitment boxes that were deposited at 2000 m off the east coast of the United States and retrieved at varying intervals. Within two months individuals had grown to adult size, and a female that had settled in a box that was retrieved after one year was sexually mature with ripe eggs. Reproduction is apparently not seasonal (Blake & Watling 1994).
General References
Belyaev, G.M. 1989. Glubokovodnii Okeanicheskii Zheloba i ikh Fauna. Moscow : 'Nauka'.
Blake, J.A. & Watling, L. 1994. Life history studies of deep-sea benthic infauna: Polychaeta, Aplacophora, and Cumacea from the continental slope off Massachusetts. pp. 244-260 in Young, C.M. & Eckelbarger, K.J. (eds). Reproduction, Larval Biology, and Recruitment of the Deep-Sea Benthos. New York : Columbia University Press.
Ivanov, D.L. & Scheltema, A.H. 2000. Prochaetodermatidae of the Western Indian Ocean and Arabian Sea. in press in Bouchet, P. & Marshall, B.A. (eds). Rés. Camp. MUSORSTOM. Vol. 22. Paris : Mém. Mus. Nat. Hist. Natl.
Salvini-Plawen, L.v. 1992. On certain Caudofoveata from the Vema-Expedition. pp. 317-333 in Gittenberger, E. & Gould, J. (eds). Proceedings of the 9th International Malacological Congress. Leiden : Unitas Malacologia.
Scheltema, A.H. 1981. Comparative morphology of the radulae and alimentary tracts in the Aplacophora. Malacologia 20: 361-383
Scheltema, A.H. 1985. The aplacophoran family Prochaetodermatidae in the North American Basin, including Chevroderma n.g. and Spathoderma n.g. (Mollusca: Chaetodermomorpha). Biological Bulletin. Marine Biological Laboratory (Woods Hole) 169: 484-529
Scheltema, A.H. 1987. Reproduction and rapid growth in a deep-sea aplacophoran mollusc, Prochaetoderma yongei. Marine Ecology Progress Series 37: 171-180
Scheltema, A.H. 1989. Australian aplacophoran molluscs: I. Chaetodermomorpha from Bass Strait and the continental slope off southeastern Australia. Records of the Australian Museum 41: 43-62
Scheltema, A.H. 1997. Aplacophora molluscs: deep-sea analogs to polychaetes. Bulletin of Marine Science 60: 575-583
Scheltema, A.H. & Ivanov, D.L. 2000. Prochaetodermatidae of the Eastearn Atlantic Ocean and Mediterranean Sea (Mollusca, Aplacophora). Journal of Molluscan Studies 66: 313-362
History of changes
| Published | As part of group | Action Date | Action Type | Compiler(s) |
|---|---|---|---|---|
| 12-Feb-2010 | (import) |