Glyphidrilus singaporensis, Shen & Yeo, 2005

Shen, Huei-Ping & Yeo, Darren C. J., 2005, Terrestrial Earthworms (Oligochaeta) From Singapore, Raffles Bulletin of Zoology 53 (1), pp. 13-33 : 18-20

Glyphidrilus singaporensis , new species

( Fig. 3 )

Material examined. – Holotype – 1 mature (clitellate) specimen (dissected)( ZRC), Jungle Fall Valley , Bukit Timah, coll. K. K. P. Lim, D. C. J. Yeo & K. L. Yeo, 5 Mar.2003.

Table 3. A comparison of characters among Glyphidrilus malayanus Michaelsen , G. gatesi , new species, G. spelaeotes Stephenson , G. singaporensis , new species, G. jacobsoni Michaelsen , and G. horsti Stephenson.

Paratypes – 2 mature (clitellate) and 9 immature (aclitellate) specimens ( ZRC), same collection data as for holotype .

Others – 2 not fully matured and 2 immature (aclitellate) specimens (all amputated)( ZRC), Nee Soon swamp forest along pipeline, coll. K. L. Yeo, K. K. P. Lim & David Nasir, 18 Mar.2003 .

Description. – Length (mature) 112-142 mm, wing width 3.9- 4.65 mm. Segments numbering 163-220. Prostomium zygolobous. Tail pointed. Dorsal pores absent. Clitellum from XVIII or XIX to XXVII or 1/2 XXVIII. Wings lateral to b, XXI-XXV; its anterior edge covered the posterior portion of XX and its posterior edge reached the anterior portion of XXVI. Setae paired, preclitellum: aa = 2ab, bc = 2cd, aa = 0.63dd; postclitellum: aa = 2.4ab, bc = 2.3cd, aa = 0.54dd. Genital papillae postsetal; lateral series paired or asymmetrical, lateral to or in line with b on XII-XIV, XVIII- XX and XXVI-XXVII; unpaired median series between aa on XVII-XX and XXVII-XXX; number and position variable among specimens ( Figs. 3 A-D). Each papilla round, 0.6-0.65 mm in diameter. Male pores, female pores, and spermathecal pores not visible. Specimens pale fleshy, darker around clitellum.

Gizzard in VIII. Intestine origin in XV, enlarged from XVII. Dorsal blood vessel aborted anterior to segment IX. Hearts IX-XI. Nephridia holoic. Seminal vesicles four pairs in IX-XII; last pair large to push septum 12/13 against septum 13/ 14. Testes shiny in X and XI. Prostate and accessory glands absent. Spermathecae sessile, globular, about 0.4 mm in diameter, one on each side of segment XIV, and one to five (usually three) on each side per segment in XV-XVII ( Fig. 3E ).

Etymology. – The name “ singaporensis ” is given to this species for its type locality in the Jungle Fall Valley in Bukit Timah, Singapore.

Remarks. – Glyphidrilus singaporensis , new species, is fairly similar to Glyphidrilus jacobsoni ( Michaelsen, 1922) from Sumatra in the locations of wings and lateral genital papillae (see Table 3). However, G. jacobsoni has longer body length of 160 mm and higher segment number of 274 than G. singaporensis , which is 112-142 mm in length and 163-220 in segment number. Also, G. singaporensis has clitellum from XVIII or XIX to XXVII or 1/2 XXVIII, whereas G. jacobsoni has clitellum in XVIII-XXX (see Table 3). Michaelsen (1922) did not mention median papillae and the internal characters in the original description of G. jacobsoni .

Glyphidrilus singaporensis of Singapore differs from G. gatesi of Sungei Kayu swamp forest of Malay Peninsula by the former having wings in XXI-XXV and one to five (usually three) spermathecae on each side per segment in XIV-XVII, whereas the latter has wings from XVIII or XIX to 1/2XXIV or XXIV and three spermathecae on each side per segment in XV-XVII.

Glyphidrilus singaporensis is also similar to G. horsti in the positions of clitellum, wings and median genital papillae (see Table 3). However, G. singaporensis is larger, and has three pairs of hearts in IX-XI and one to five (usually three) spermathecae on each side per segment in XV-XVII, whereas G. horsti is much smaller, has four pairs of hearts in VIII-XI and two spermathecae on each side per segment in XV-XVII.

Figures

Fig. 3. Glyphidrilus singaporensis, new species. A, right lateroventral view of wings and genital papillae (gp) of holotype; B, left latero-ventral view of genital papillae of a 140-mm paratype; C, right latero-ventral view of wings and genital papillae of a 140-mm paratype; D, ventral view of wings and genital papillae of a 112- mm paratype; E, dorsal view of spermathecae of holotype.