Alluroididae
| Alluroididae | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Alluroididae | ||||||||||||
| Michaelsen , 1900 |
The family Alluroididae , which forms the order of the Alluroidida with the monotypic family Syngenodrilidae , is a taxon of earthworm-like little bristles (Oligochaeta) in the ringworm class of belt worms (Clitellata), which are common in inland waters in Africa and South America .
features
The Alluroididae have 4 pairs of simple, S-shaped bristles per segment . In contrast to the Crassiclitellata , to which the earthworms belong, the Alluroididae have an inconspicuous clitellum , which consists of only one layer of cells and extends from the 12th or 13th to the 16th segment.
The Alluroididae, like all belt worms, are hermaphrodites . They are protandric and metagynous, so they have a pair of testes in the 10th segment and a pair of ovaries in the 13th segment, with Kathrynella guyanae each one segment behind. The pair of male genital orifices is located on the abdomen to the side in the bristle arch of the 13th or 14th segment, the pair of female genital orifices on the front edge of the 14th segment. The openings of the receptacula seminis are paired and to the side or unpaired and in the middle of the abdomen in a maximum of 3 pairs between the 6th and 9th segment, but never in a row with the male genital openings . The sperm funnels are oriented anterodorsally. The sperm vesicles protrude into the segment behind the testicles, but can also be absent, with spermatogenesis taking place in the testicle-bearing segment.
The prostates or atria are tubular or bulbous and accommodate the sperm conductors or open like these into an end chamber. They consist of an inner epithelium that is enveloped by a muscular sheath and further outside by prostate cells, from which small tubes lead through the muscle layer into the atrium. An elongated penis , terminally filled with sperm, may also be present. Genital or penis bristles are not always present. The ice sacs extend from the ovary-bearing segment through several segments to the rear.
Distribution, habitat and way of life
The Alluroididae are mainly found in Africa . As freshwater inhabitants, they inhabit the bottom of various inland waters and, like other Crassiclitellata, live as substrate eater, digesting the organic components of the swallowed mud or sand.
Sample species and their distribution
Alluroides pordagei Beddard, 1894 isnativeto Kenya and was first found near Mombasa . Alluroides tanganyikae Beddard, 1906 is known from Tanganyika ( Tanzania ), while Alluroides brinkhursti Jamieson, 1968 was found on the slopes of Mount Elgon in Uganda . Standeria transvaalensis Jamieson, 1968, livesin the Transvaal ( South Africa ). In 1964, however, a species was also found in Argentina and initially named Alluroides americanus , today Brinkhurstia americana (Brinkhurst, 1964) .
Genera
The family Alluroididae includes the following six genera :
- Alluroides Beddard, 1894
- Barryjamiesonia Ljunström, 1971
- Brinkhurstia Jamieson, 1968
- Kathrynella Omodeo, 1996
- Righiella Omodeo & Coates, 2001
- Standeria Jamieson, 1968
literature
- Wilhelm Michaelsen : Oligochaeta: Vermes. R. Friedländer and Son, Berlin 1900. Alluroididae , p. 106.
- Wilhelm Michaelsen (1913): Oligochetes from tropical and south-subtropical Africa. Zoologica 67, pp. 139-170.
- RO Brinkhurst, 1964. A taxonomic revision of the Alluroididae (Oligochaeta). Proceedings of the Zoological Society of London 142, pp. 527-536.
- Barrie GM Jamieson. 1968. A taxonometric investigation of the Alluroididae (Oligochaeta). Journal of Zoology (Lond.) 155, pp. 55-86.
- Barrie GM Jamieson. 1971. Alluroididae. In: RO Brinkhurst and BGM Jamieson (eds), Aquatic Oligochaeta of the World. Oliver and Boyd, Edinburgh, Toronto. Pp. 708-722.
- Barrie GM Jamieson, Marco Ferraguti: Non-leech Clitellata. In: Greg Rouse, Fredrik Pleijel (Eds.): Reproductive Biology and Phylogeny of Annelida. Science Publishers, Enfield (NH) 2006. Chapter 8, pp. 235-392, here Suborder Alluroidina, Superfamily Alluroidoidea, Alluroididae pp. 309-311.