Microchaetidae Beddard, 1895

Jadwiga Danuta Plisko, 2006, A systematic reassessment of the genus Microchaetus Rapp, 1849: its amended definition, reinstatement of Geogenia Kinberg, 1867, and erection of a new genus Kazimierzus (Oligochaeta: Microchaetidae), African Invertebrates 47 (1), pp. 31-56 : 33-35

Family Microchaetidae Beddard, 1895

Microchaeta Perrier, 1881 : Benham 1886 a, 1886 b, 1892; Beddard 1886 a, 1886 b, 1891, 1895; Rosa 1887,

1891, 1897, 1898; Michaelsen 1899 a, b.

Geoscolecidae ( Microchaeta ): Benham 1890.

Geoscolecidae [partim]: Rosa 1891, 1893 [inclusion of Microchaeta species].

Microchaetinae (Geoscolicidae) [partim]: Beddard 1895: 664 [inclusion of Microchaeta species; incorrect

emendation of Geoscolecidae; the name ‘Microchaetidae’ is used on page 664].

Microchaetinae ( Glossoscolecidae ): Michaelsen 1900: 447; 1910: 158; 1913 c: 422; Stephenson 1930: 899

[partim]; Pickford 1975: 17.

Glossoscolecidae [for Microchaetus species]: Michaelsen 1913 a: 542.

Microchaetinae ( Lumbricidae ): Michaelsen 1918: 305.

Microchaetidae (Lumbricina) : Michaelsen 1928: 107.

Microchaetini (tribe in Glossoscolecinae): Brinkhurst & Jamieson 1971.

Microchaetidae : Gates 1959: 255; Ljungström & Reinecke 1969: 215; Reinecke & Ryke 1969: 515; Reynolds & Cook 1976: 2; Omodeo 1998: 53; 2000: 184; Sims 1978: 662; 1980: 110; 1982: 285; Jamieson 1980: 268; Hodgson & Jamieson 1992: 57; Reynolds 1993: 2; Zicsi & Pajor 1992: 129; Plisko & Zicsi 1991: 111; Plisko 1992: 337; 1996 a: 288; 2005: 104; 2006: 17–42 [and in all other papers dealing with microchaetids].

The following account of family characters is based on those published for Micro- chaetinae, Microchaetidae or Microchaetini (Beddard 1895; Michaelsen 1900, 1918, 1928; Gates 1959; Brinkhurst & Jamieson 1971; Plisko 1996 a, 2006), and augmented in the present study.

Diagnosis: Testes and male funnels set in holandric, proandric or metandric arrangement. Excretory system holonephric or meronephric; holonephridia with nephridial bladers V- or J- shaped. Gizzards oesophageal; one or two, present in segments 6, or 6–7, or 7, or 6–7 and 9; encircling oesophageus, horseshoe-shaped, or as separated dorsolateral glands. Dorsal blood vessel variable: simple through the whole body, or double in certain preclitellar segments, and being simple or double when crossing septa. Calciferous glands oesophageal, restricted to one or two segments, in area 9–11. Spermathecae tubular or globular, in simple pairs, or multiple. Intestine commencing in 12, 13 or 14. Typhlosole present, commencing immediately with intestine, or posterior to intestine segments. Vasa deferentia uncovered, or embedded in body wall. Seminal vesicles paired or fused dorsally, confined to one or to two segments, or stretching posterior to one or more segments. Ovaria in 13. Septa variably thickened in various anterior segments. Spermathecal pores in pre-testis, testis, or post-testis intersegmental furrows, or intrasegmentally. Female pores paired in 14, or in 13/14. Male pores paired, post-testicular, in clitellar area, intersegmental or intrasegmental.

Secondary annulation on preclitellar segments present, variable. Body length and segment number highly variable. Setae in lumbricinae arrangement, in regular rows, or in a few preclitellar or postclitellar segments irregularly settled. Nephridial pores present or absent. Clitellum and tubercula pubertatis present in mature individuals, located variably. Papillae present or absent. Genital glands present or absent; if present, variable in size, shape and location. Dorsal pores absent. Copulatory sacs absent. Prostates absent. Notes: Six genera now constitute the family, i.e. Microchaetus emend., Geogenia stat. rev. and Kazimierzus gen. n. (considered in this paper), Tritogenia, Michalakus and Proandricus . The genera Microchaetus and Geogenia comprise species with holandric, holoic conditions. Kazimierzus gen. n. consist of holandric and metandric species, with holoic excretory system. Tritogenia and Michalakus are constituted by holandric, meronephric species. Proandricus species are characterised uniformly by the proandric condition.

Distribution:The entire family Microchaetidae , as it is presently recognised, is restricted to southern Africa. Its representatives are known from South Africa, Lesotho and Swaziland. Occurrence of some species might be expected in adjacent parts of Mozambique, Zimbabwe and possibly also Botswana.

Key to genera of Microchaetidae

1 Excretory system meronephric; nephropores absent ............................................ 2

– Excretory system holonephric; nephropores present; only one gizzard present, in segment 7 .............................................................................................................. 3

2 One gizzard in segments 6 or 6–7 ........................................... Tritogenia Kinberg

– Two gizzards; one in segments 6–7, second in segment 9 ....... Michalakus Plisko

3 Testes and male funnels in proandric arrangement.................. Proandricus Plisko

– Testes and male funnels in other than proandric arrangement ............................. 4

4 Testes and male pores in holandric arrangement; nephridial bladders V-shaped; dorsal blood vessel double in certain preclitellar segments, simple when crossing septa ...................................................................................................................... 5

– Testes and male pores in holandric or metandric arrangement; nephridial bladders J-shaped; dorsal blood vessel simple through whole body.Two or one pair of seminal vesicles confined to one, two, or extended in more segments; some of septa 4/5– 9/10 variably thickened. Mature individuals 80–500 mm, 135–500 segments ...... ............................................................................................... Kazimierzus gen. n.

5 Spermathecae always posterior to testis locations; spermathecal pores in four 12/13, 13/14, 14/15, 15/16 or five 12/13, 13/14, 14/15, 15/16, 16/17 intersegmental furrows; occasionally in some conspecific populations a posterior row of spermathecae and their pores (16/17 or 15/16) are reduced; septa 4/5, 5/6, 7/8, 8/9 thickened firmly. Mature individuals large; length nearly 1 meter or more, some species extending to more than 2 meters; segment number over 500, can exceed 1200 .................................................................................. Microchaetus Rapp , emend.

– Spermathecae present anterior or posterior to testis locations, or in testicular segments; spermathecal pores in one, two, three or more intersegmental furrows; if in more furrows, the anterior pairs of spermathecal pores occur anterior to, or in testis segments; two, three, four or five septa 4/5–8/9 selectively, variably thickened. Mature individuals small or medium, not reaching more than 500 mm in length; segment number 100–500 ......................................... Geogenia Kinberg , stat. rev.