Dendrobaena Eisen, 1873

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 : 693-694

Genus Dendrobaena Eisen, 1873

Four species in RSA: D. cognettii (Michaelsen, 1903) , D. hortensis ( Michaelsen,

1890), D. octaedra ( Savigny, 1826) , and D. veneta veneta ( Rosa, 1886) .

1 Setae widely spaced in eight regular lines ( Fig. 9C ). Clitellum on 28, 29–33. Tubercula pubertatis on 31–33, as small bands .......... D. octaedra ( Savigny, 1826) Description: Body length 30–60 mm. Colour violet-reddish, often iridescent. First dorsal pore in 4/5. Spermathecal pores in three intersegmental furrows 9/10, 10/11, 11/12. Spermathecae in 9, 10, 11. Seminal vesicles in three segments, 9, 11, 12. Calciferous glands in 11–12 with well-developed lateral pouches in both segments. Holandric. Excretory system holoic, with nephridial bladders ‘octaedra’ shaped.

Notes: Palearctic species, broadly distributed worldwide.Reproduces biparentally and parthenogenetically, with high morphological variations, and variable morphs. Epigeic. In RSA occurs commonly in plantations and forests into which foreign plants or trees have been introduced. Nearly thirty records refer to protected areas (Plisko 2010). Known from high altitudes above 1700 m in the Drakensberg mountains. Noted together with other introduced lumbricids and megascolecids.

– Setae in four distant pairs. Clitellum on 26, 27–32, 33. Tubercula pubertatis on 30–31 ....................................................................... D. veneta veneta ( Rosa, 1886) Description:Body length 35–100 mm. First dorsal pore in 5/6. Male pore glands slightly protruding onto neighbouring segments.Spermathecal pores in 9/10 and 10/11. Septa 7/8–9/10 thickened. Spermathecae in 9 and 10. Seminal vesicles in 9, 10, 11, or 11 and 12. Calciferous glands in 10–12, with no lateral pouches. Excretory system holoic, with small nephridial bladders.

Notes: Origin in East Mediterranean area; spread to other European countries and also to other continents in tandem with the developing vermicomposting industry. Synantropic. In RSA it is recorded from garden soil and composting heaps (Plisko 2010). Common in vermicomposting. Muyima et al. (1994) studied the species’ adaptability for vermicomposting production.

2 Clitellum on segments 33–36, 37. Tubercula pubertatis absent. Setae distantly located, in pairs ................................................... D. cognettii (Michaelsen, 1903) Description: Body length 35 mm. Violet to light red dorsally, light ventrally, sometimes iridescent. Setae widely spaced, in pairs. Dorsal pores absent. Spermathecae absent. Seminal vesicles in 11, 12. Calciferous glands in 11–13, with lateral pouches in 11, 12. Excretory system holoic; nephridial bladders in postclitellar segments bilobate.

Notes: Palearctic origin. Its distribution is not well known. The initial species Descriptions were possibly based on a parthenogenetic morph, and its small size has put the species’ validity in question for nearly a century. The species’ taxonomical position was discussed by Csuzdi and Zicsi (2003) and a species revision was suggested. Blakemore (2010) synonymised D. cognettii with a few other controversial species, which together probably form a highly polymorphic parthenogenic species-complex. In RSA the species was found only in the Cape Peninsula ( WC) in the litter of a pine plantation that has been integrated into the indigenous Newlands Forest .

– Clitellum on 27–33. Tubercula pubertatis on 30–32, 33 .......................................... ............................................................................... D. hortensis ( Michaelsen, 1890) Description: Body length 70–125 mm. Setae in eight rows with distance between ab and cd shorter than bc. First dorsal pore in 5/6. Male pores with moderate glandular tumescens protruding onto neighbouring segments. Spermathecal pores present, in 9/10 and 10/11. Septa 7/8–9/10 thickened. Spermathecae in 9 and 10. Seminal vesicles in 9, 10, 11, or 11 and 12. Calciferous glands in 11–13, lateral pouches lacking. Holandric. Excretory system holoic, nephridial bladders sausage–shaped.

Notes: Known from Central and Western Europe, distributed over Europe and other continents mainly in connection with the vermicomposting industry. Synantropic, occurs in manure, composting heaps or any litter rich in decaying organic matter. In RSA it is recorded from garden soil and composting heaps (Plisko 2010).

Figures

Fig. 9. Setal arrangements: (A –C) lumbricine arrangement: (A) closely paired; (B) widely paired; (C) separated in eight rows; (D) perichaetine arrangement.