Pontoscolex corethrurus Müller, 1857

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 : 686-687

Pontoscolex corethrurus Müller, 1857

Description: Unpigmented. Body length 40–120 mm. Setae alternate/irregular: anterior closely paired, gradually wider apart, hind body with the quincunx arrangement (e.g. setal couples are alternately closely and widely paired on successive segments). Prostomium and peristomium invaginated inside the cavity forming a ‘proboscis’. Preclitellar segments may be slightly marked transversely with thin grooves, not connected to the septa. Caudal zone present or absent. Clitellum saddle-shaped on segments 15–22, 23. Tubercula pubertatis as a band on 19, 20–21, 22. Five pairs of the lateral hearts in 7–11 respectively. Calciferous glands extramural in segments 7–9. Typhlosole present in segments 21–24, terminates in area of segment 100. Seminal vesicles present or absent. If present, one pair in 12, extending variably to segment 20 or 22. Spermathecae present, three pairs, each in 7–9 respectively, adiverticulate; ampulla slightly elongated with duct longer than ampulla.

Notes: The species extends over a large part of the tropical/subtropical zone, mainly due to anthropogenic dispersal. Its great adaptability to variable ecological conditions has allowed it to spread in the tropics, especially near the coastal zone. In RSA the species occurs in the subtropical northeastern areas, in the coastal zone and in the hinterland along the Indian Ocean, south of the tropic, extending to 31ºS latitude (Plisko 2001). The majority of the samples (ca. 70 %) came from agricultural environments, to which the species was directly or indirectly introduced. Passive transport of the species has been observed, and Van Bruggen (1964) has noted this kind of infestation in South African soils. This species is commonly used in agriculture practices for crop improvement in a number of countries ( AvendaÑo-YáÑez et al. 2014), although this practice has not yet been introduced in this country.