Spionida

Spionida
Magelona johnstoni with her long palps
Systematics
Over trunk : Lophotrochozoa (Lophotrochozoa) Trunk : Annelids (Annelida) Class : Polychaete (Polychaeta) Subclass : Palpata Order : Canalipalpata Subordination : Spionida
Scientific name
Spionida
Dales , 1962

Spionida is the name of a sub-order of mostly sessile and tube -building polychaeta living as filter feeders in the order Canalipalpata and the subclass Palpata , which can be found in oceans worldwide to depths of 200 m.

features

The Spionida are characterized by the fact that the two palps , on which there are no tentacle-like extensions, are not located on the prostomium , but on the peristomium directly behind it . In addition, the two nuchal organs are characteristically elongated into rearward-facing appendages. As with other Canalipalpata, the mouth has no jaws or teeth, but the pharynx is partially evertable. Some species have small eye spots and some have a central sensory lobe. A pair of gills are attached to each of the anterior segments . The parapodia have large lamellae behind the bristles. The bristles are unbranched capillary-like bristles, spikes and hooks.

Distribution, way of life and example species

The Spionida are widespread in seas around the world and live mainly on soft, sandy or muddy subsoil in the intertidal zone and down to depths of no more than 200 m, where they build their living tubes and live as sessile animals . They feed the filter feeders of detritus and phytoplankton , which they catch with their palps of the ocean current and transport with eyelashes activity on the palps to mouth.

Systematics

The suborder Spionida belongs to the order Canalipalpata in the subclass Palpata according to the systematics according to Rouse & Fauchald from 1998 .

According to this system, the following families belong to the subordination Spionida :

• Apistobranchidae
• Spionidae
• Trochochaetidae
• Longosomatidae
• Magelonidae
• Poecilochaetidae
• Chaetopteridae

literature

• Rodney Phillips Dales (1962): The polychaete stomatodeum and the inter-relationship of the families of the Polychaeta. Proceedings of the Zoological Society of London 139, pp. 389-428.
• Stanley J. Edmonds: Fauna of Australia, Volume 4A. Polychaetes & Allies. The Southern Synthesis 4. Commonwealth of Australia, 2000. Class Polychaeta. Pp. 256f., Spionida.
• Gregory W. Rouse, Kristian Fauchald (1998): Recent views on the status, delineation, and classification of the Annelida. (PDF). American Zoologist. 38 (6), pp. 953-964. doi: 10.1093 / icb / 38.6.953
• Peter Ax: The system of Metazoa II. A textbook on phylogenetic systematics. Gustav Fischer Verlag, Stuttgart / Jena 1999. pp. 47–56, chapter Polychaeta : Spionida , p. 53.

Web links

Commons : Spionida  - collection of pictures, videos and audio files

• Fredrik Pleijel and Gregory W. Rouse: Spionida. In: The Tree of Life Web Project, 2004.