Amynthas Kinberg, 1867

Plisko, Jadwiga D. & Nxele, Thembeka C., 2015, An annotated key separating foreign earthworm species from the indigenous South African taxa (Oligochaeta: Acanthodrilidae, Eudrilidae, Glossoscolecidae, Lumbricidae, Megascolecidae, Microchaetidae, Ocnerodrilidae and Tritogeniidae), African Invertebrates 56 (3), pp. 663-663 : 697

Key to introduced species of Amynthas Kinberg, 1867

1 Spermathecal pores paired, present in one intersegmental furrow (5/6), degraded or absent. ......... A. minimus (Horst, 1893) species-group ( Sims & Easton 1972: 213) Description: Length 20–40 mm. Number of segments 70–80. First dorsal pore in 11/12. Clitellum on 14–16, sometimes degraded. Female pore minute on 14. Male pores paired on 18, variably raised on small porophores. Genital markings present or absent. Septa 5/6, 6/7 and 7/8 moderately thickened, 8/9 and 9/10 aborted. Gizzard in 8–9. Intestinal origin in 15. Caeca simple, originating in 27, extended forwards to 24. Spermathecae, degraded or absent; if present in 6. Seminal vesicles present, degraded or absent. Prostates present in 17–19, or degraded. Copulatory pouches lacking Notes: Described under numerous synonyms (Blakemore 2010) and is known worldwide. Thecate and athecate populations are also known from many parts of the world (Blakemore 2010) and from RSA (Plisko 2010; NMSAD).The large population of athecate, degraded specimens collected in QEP ( Nxele 2012) indicates parthenogenetic reproduction. Ljungström (1972) likewise collected parthenogenetic morphs with spermathecae and seminal vesicles developed, degraded or absent. Abnormality in the development of the clitellum was also observed. The species is known from grasslands and meadows, and forested, natural and cultivated land (Zicsi 1998; Plisko 2010). Thecate degeneration is attributed to the parthenogenetic reproduction, and has been widely discussed ( Gates 1932, 1972; Tsai et al. 2002; Blakemore 2003, 2010) with the species’ systematic position being considered (Gates 1972; Sims & Easton 1972; Blakemore 2003). Indicated as a ‘ minimus species-group’ by Sims and Easton (1972: 213), following Gates’s (1932) ‘ illotus­ group’.

– Spermathecal pores in more than one intersegmental furrow.................................2

2 Spermathecal pores in two intersegmental furrows ................................................3

– Spermathecal pores in three or four intersegmental furrows ..................................4

3 Spermathecal pores in intersegmental furrows 5/6, 6/7. ........................................... ................... A. morrisi (Beddard, 1892) species-group ( Sims & Easton 1972: 236). Description: Length 63–107 mm. Segments 73–97. Setae numerous, ca. 40–50 per segment. First dorsal pore in 10/11. Spermathecal pores minute, superficial. Male pores minute on small disc-shaped porophores. Clitellum annular on 1/ n14, 14 –1/n16. Genital markings present, variable; paired, disc-shaped on 6–7, two or three on each porophore forming a triangle; one to six pre-setal markings on 17 or 18 or 19 or 20. Septa 4/5/–7/8 thickened, 8/9, 9/10 absent. Gizzard in 7/8–9/10. Intestine originates in 15. Caeca simple, originates at 27 and extends forwards to 24. Spermathecae paired, in 6 and 7 respectively; spherical ampulla with long slender duct with a single diverticulum. Seminal vesicles in 11–12. Prostatic glands, multi-branched in 17/18–19/20, ducts muscular with single loops. Notes: Species known under numerous synonyms (revised by Blakemore 2010.Distributed worldwide in tropical and temperate regions. In RSA collected from a riverbank in Potchefstroom (NW), and from the Sabie area (MP). Recorded in the NMSAD from Pretoria city parks (GP) (Plisko 2010). May be found in pastures, grasslands, in riverbanks in the gravel of the waterline, and in the moist, rich organic matter found in the top layer of the soil. Indicated as a ‘ morrisi species-group’ by Sims and Easton (1972: 236).

– Spermathecal pores in intersegmental furrows 7/8 and 8/9 ...................................... ............. A. aeruginosus Kinberg, 1867 species group ( Sims & Easton 1972: 234). Description: Length 50–115 mm. Segments 80–110. Pigmented, with brown-violet tint. Prostomium epilobous. First dorsal pore in 11/12. Female pore single, mid-ventral in 14, inconspicuous. Male pores paired in 18, on small porophores (copulatory pouches absent). Genital papillae and markings present, variable. Intestinal caeca paired, simple; initiate in 27 and extend forwards to 19, 18. Last pair of hearts in 13. Testis enclosed. Seminal vesicles paired, in 11 and 12, respectively. Ovaries paired in 13. Prostatic glands in 18; large, extending forwards to 17, 16, and backwards to 19, 20. Prostatic ducts short, muscular with slender ental region. Spermathecae in 8 and 9; ampulla and duct similar length; diverticulum slender with convoluted end.