Holotype ♂ (LKCNHM), SINGAPORE: Bukit Timah Nature Reserve, Seraya Loop, altitude 118 m, 1°21'25.4"N, 103°46'25.3"E, 17 August 2015, S. Li and Y. Tong leg. Paratypes 4♂ and 2♀ (LKCNHM), same data as holotype.

3♂ and 2♀ (NHMSU), SINGAPORE: Bukit Timah Nature Reserve, Seraya Loop, altitude 118 m, N1°21'25.4", E103°46'25.3", 17 August 2015, S. Li and Y. Tong leg.

Singaporemma halongense Lehtinen, 1981 (Figs 19A, 21A–D; Lehtinen, 1981: 31, figs 43, 49, 54, 58, 62). Paratype 1♂ (ZMUT), VIETNAM: Quang Ninh, Ha Long, in litter of brook valley, altitude 30 m, 11 October 1978, P.T. Lehtinen leg.

Patronymic in honour of Dr Lena Chan from the National Biodiversity Centre, Singapore in recognition of her support of this study; noun (name) in genitive case.

This new species can be distinguished from all other congeners with the exception of Singaporemma banxiaoensis Lin & Li, 2014, Singaporemma halongense and Singaporemma singulare by the slender, straight embolus without any furcated end (Fig. 17B–E), the lack of central process, and the “T”-shaped inner vulval plate (Fig. 20C). It differs from Singaporemma banxiaoensis (see Lin and Li, 2014: 42, fig. 5A–D) by the lower initial position of embolus (Fig. 17A vs. fig. 5A), the wider embolic end (Fig. 17D, 19B–C vs. Fig. 5D), the wider, shorter preanal scutum (Fig. 20B vs. Fig. 6B), the narrower lateral horns, and the “T”-shaped inner vulval plate (Fig. 20C vs. Fig. 6C). Differs from Singaporemma halongense (see Figs 19A, 21A–D, and Lehtinen, 1981: 31, fig. 58) by the sharper, narrower embolic end (Fig. 19B–I vs. Fig. 19A), the wider preanal scutum and the “T”-shaped inner vulval plate (Fig. 20B–C vs. fig. 58). From Singaporemma singulare (see Figs 23A–E, 25A–E) by the shorter ovate bulb (Fig. 18A–F vs. Fig. 23A–C, 25D–E), the bent embolic end (Fig. 17D, 19B–I vs. Fig. 23D, 25C), the more swollen palpal tibia (Fig. 18A–F vs. Fig. 23A–B, 25D–E), the narrower postgenital scutum and preanal scutum (Fig. 20B vs. Fig. 23H, 26B), and the larger inner vulval plate (Fig. 20C vs. Fig. 26C).

Male (holotype). Coloration: body reddish-brown; legs yellowish-brown.

Measurements: total length 0.86; carapace 0.42 long, 0.38 wide, 0.40 high; abdomen 0.58 long, 0.49 wide, 0.39 high; clypeus 0.17 high; sternum 0.24 long, 0.27 wide. Length of legs: I 0.95 (0.31, 0.11, 0.22, 0.15, 0.16); II 0.87 (0.27, 0.10, 0.20, 0.15, 0.15); III 0.77 (0.24, 0.10, 0.16, 0.14, 0.13); IV 0.99 (0.33, 0.11, 0.23, 0.17, 0.15).

Prosoma (Fig. 16A–B, E, G): carapace finely reticulated; eyes white, AME=ALE>PLE in size, ARE procured; clypeus high, sloping forward, marginally rounded (Fig. 16C, 16G); cephalic part raised, quadrate (Fig. 16A); thoracic part smooth in radial grooves; Chelicerae without any horn or process, cheliceral lamina developed; endites basally wide, distally narrow; labium triangular, distally blunt; sternum finely reticulated, scutellate, posterior corner blunt, margin rugose, with sparse setae. Legs cuticle striated.

Opisthosoma (Fig. 16A–B, G): covered with serrated setae; dorsal scutum oval, but anteriorly truncated, finely reticulated; ventral scutum reticulated; lateral scutum long, and exceeding beyond the posterior margin of preanal scutum; perigenital scutum present; postgenital scutum straight, narrow, same wide as preanal scutum; preanal scutum shallow rectangular.

Palp (Figs 17A–E, 18A–F, 19B–I): femoral cuticle sculptured and granulated, approximately 2.5 times patella in length; patella short, and small; tibia remarkably swollen, about 2.3 times femur in width (Fig. 17B–C, E); cymbium relatively small, bearing long setae; bulb egg-shaped, its surface with irregular lines (Fig. 17A–B); embolus long, straight, starting at the subapical 1/3 position of bulb prolaterally (Fig. 17B–C, 18A–F), embolic end slightly bent, sharp and flexible (Figs 17D, 19B–I).

Female (one of paratypes). Coloration: same as in male.

Measurements: total length 0.96; carapace 0.44 long, 0.38 wide, 0.41 high; abdomen 0.64 long, 0.52 wide, 0.40 high; clypeus 0.15 high; sternum 0.26 long, 0.27 wide. Length of legs: I 0.91 (0.28, 0.12, 0.20, 0.15, 0.16); II 0.83 (0.26, 0.11, 0.18, 0.14, 0.14); III 0.76 (0.24, 0.10, 0.16, 0.13, 0.13); IV 0.98 (0.32, 0.11, 0.22, 0.17, 0.16).

Prosoma (Fig. 16C–D, F, H) as in male, but clypeus slightly lower than in male. Palps distinctly reduced. Legs also as in male.

Opisthosoma (Figs 16C–D, H; 20A): dorsal and ventral scuta as in male; lateral scutum I long, extending beyond posterior margin of preanal scutum; perigenital scuta small, oval; postgenital scutum slightly curved, wider than preanal scutum; preanal scutum sculptured, shallow rectangular, with sparse serrated setae.

Genitalia (Fig. 20B–D): epigynal pit distinct, oval (Fig. 20B, D); vulval posterior margin weakly sclerotized (Fig. 20C); vulval stem triangular; central process absent; inner vulval plate “T”-shaped (Fig. 20C); lateral horn narrow, and weakly sclerotized; vulval ducts relatively wide, membranous and translucent, connected to the rugose, large, saccular seminal receptaculum (Fig. 20C).

Singapore.