Glyphidrilus singaporensis Shen & Yeo, 2005

Chanabun, Ratmanee, Bantaowong, Ueangfa, Sutcharit, Chirasak, Tongkerd, Piyoros, James, Samuel W. & Panha, Somsak, 2012, A New Species Of Semi-Aquatic Freshwater Earthworm Of The Genus Glyphidrilus Horst, 1889 From The Mekong River (Oligochaeta: Almidae), Raffles Bulletin of Zoology 60 (2), pp. 265-277 : 274

Glyphidrilus singaporensis Shen & Yeo, 2005

( Figs. 3C , 7)

Glyphidrilus singaporensis Shen & Yeo, 2005: 18 , Fig. 3 . Type locality: Jungle Fall Valley , Bukit Timah, Singapore.

Material examined. — Holotype in the ZRC, RMBR ( Fig. 7A, B). Additional records: 10 adults ( CUMZ 3217 , Figs. 3C , 7C, D), Bukit Timah Nature Reserve , Singapore. 1°21'24.11"N, 103°47'6.76"E, 64 m in elevation (25 Dec.2009).

Description. — Dimensions: 101–143 mm body length by 4.2–3.8 mm at the anterior body region, body cylindrical at the anterior part but quadrangular in transverse section after clitellum, with 181–341 segments. The body colour pale brown. Dorsal surface considerably broader than ventral at the posterior end. The clitellar wings on ventro-lateral part of the clitellum in 21–½26, 26, 3.8–4.3 mm long, and 0.7–0.8 mm wide on both sides. Prostomium zygolobous. Dorsal pores absent. Clitellum annular shape from 18–27, ½28, 29, 30, 31. Four pairs of setae per segment from 2. Female pores, male pores and spermathecal pores not visible. Genital markings: lateral series paired or appeared only one side, lateral to line b in 12–15, 20, 26, 27, 28; unpaired median series in 17–25, 28–30.

Septa 4/5–8/9 thick, 9/10–14/15 moderately thick and extremely thin from 15/16 to the end. Gizzard globular in 8. Intestine enlarged from 16. Hearts from 9–11. No nephridia distinguishable in the first 11 segments. Four pairs of seminal vesicles in 9–12. Ovaries in 13–14, with the portion in segment 13 larger. Prostate and accessory glands absent. Spermathecae sessile, globular, 0.2–0.4 mm in diameter, in segments 13/14–16/17, one to five on each side per segment.

Habitat. — Found in swamp forest at Bukit Timah Nature Reserve, Singapore, in the sandy loam topsoil. The soil surface was covered with organic matter and worm casts.

Remarks. — Glyphidrilus singaporensis from Jungle Fall Valley, Bukit Timah has clitellum in 18 or 19–27 or ½28, wings in 21–½26, 26, spermathecae in 15–17. The specimens collected from Bukit Timah Nature Reserve in this study were slightly different from the type specimen by the position of clitellum and wings, and by different numbers of spermathecae. We added up our own drawings of the holotype shown in Fig.7A, B, and of other topotype specimens in Fig. 7C, D, and also the colour picture in Fig. 3C .

Figures

Fig. 3. The colouration of newly collected specimens just after the first step preservation in 30% ethanol:A, Glyphidrilus mekongensis, new species (paratype CUMZ 3216); B, Glyphidrilus malayanus from Tok Bok Hotspring, Kelantan, Malaysia (CUMZ 3218); C, Glyphidrilus singaporensis topotype specimen (CUMZ 3217); D, cocoon characters of Glyphidrilus mekongensis, new species (paratype CUMZ 3216).