Gryllotalpa wallace Tan, new species

(Figs. 2 C, 2D, 2H; 3D–3F; 5)

Material examined. Holotype (male): Singapore, Bukit Timah Nature Reserve, along Dairy Farm Loop, secondary forest, coll. M. K. Tan, 2 Apr.2011 (ZRC).

Diagnosis. See key.

Description. Habitus typical of this genus (Fig. 5). Habitus characteristics rather similar to Gryllotalpa nymphicus. Ocelli medium. Pronotum oval, about 1.3 times longer than wide (n=1); with longitudinal medial furrow incomplete, distinct from slightly midpoint to the posterior end; otherwise similar. Process of anterior trochanter similar. Dactyls of anterior tibiae similar. Anterior tibiae with internal tympanum slit-shaped. Wings similar. Hind tibia armed with 3 internal subapical spines.

Male. Tegmen 1.3 times longer than wide (n=1), reaching end of the 6th abdominal tergite. Venations of right tegmen in dorsal and ventral views as shown in Figs. 2 C & 2D respectively; harp with medial area and distal area broader, with distal margin obtuse and round; cell 2 small, pentagonal with CuPaα2 gently curved, longer than wide, much less wide than harp at distal end; otherwise, description similar to Gryllotalpa nymphicus. Stridulatory file substraight, anterior and posterior ends slightly arched distally; with about 15 teeth (n=1); teeth densely distributed at the anterior end, very sparsely distributed at the posterior end and medial region (Fig. 2 H).

Genitalia as shown in Fig. 3 D–3F, rather similar to Gryllotalpa nymphicus. Transverse sclerite of epiphallus wide U-shaped centrally (Fig. 3 D); with a pair of very short median branches pointing dorsally with subacute apices; with a pair of narrow lateral branches, smoothly curved ventrally, hooked dorso-anteriorly at the apex, apically slightly hyaline, with subacute apices (Fig. 3 E). Median prolongation of epiphallus narrow; with a pair of hook-like lobes on anterior surface; concave at both lateral margins, strongly widening towards apex; flattened in dorsal surface, sharply and fairly deeply emarginated posteriorly (Fig. 3 E). Paramere of ectophallus as shaped in Fig. 3 F in ventral view; obliquely U-shaped in anterior view; internal process of ectophallus paramere pointing anterio-dorsally, apex subacute (Fig. 3 D).

Female. Unknown.

Colouration. Overall dark brown to black. Head, pronotum anterior and posteior margins near black. Abdominal sternites and thorax yellow brown to brown. Abdominal apex near black. Legs tend to be lighter brown. Dactyls in the anterior tibiae black apically.

Measurements (holotype, male). BL: 30.7, PL: 9.7, PW: 7.2, RTL: 11.4, RTW: 8.9, HFL: 9.9, HTL: 6.8, SFL: 4.1 mm.

Etymology. The species is named after Alfred Russel Wallace; noun in apposition. The type locality is near to the Wallace Education Centre, Dairy Farm Nature Park.