Holotype, male (Fig. 99a). Length 1.52 mm. Color of antennae, tarsi and tibiae ferruginous; remainder black. Body subovate, in dorsal aspect and in profile with weak constriction between pronotum and elytron. Rostrum basally with median ridge and pair of submedian ridges terminating near middle with marked protrusion, with rows of erect clavate scales; protrusion anteriorly steeply declivous, hollowed; between protuberance and epistome relatively flat, subglabrous, microreticulate; epistome at middle with dorsoposteriad directed horn, laterally with pair of denticles. Pronotum coarsely punctate-reticulate, each puncture with one clavate suberect scale. Elytra with striae deeply impressed; punctures large, each bearing one suberect scale; intervals narrow, weakly costate, subglabrous, microreticulate; apex subtruncate. Metafemur subapically with stridulatory patch. Abdominal ventrite 5 flat, coarsely punctate. Penis (Fig. 99b) with sides of body subparallel; apex rounded; transfer apparatus flagelliform; apodemes 2.9 × as long as body; ductus ejaculatorius sclerotized, swollen, apically torn off. Intraspecific variation. Length 1.52–1.79 mm. Female rostrum dorsally even, without teeth or cavities, punctate-rugose.

Holotype (SMNK): ARC2525 (EMBL # LM655862), MALAYSIA, Sarawak, Kuching, Mt. Santubong, sample 3, N01°43.884', E110°19.727', 496 m, 06-XII-2011. Paratypes (ARC, SMNK): MALAYSIA, Sarawak, Kuching: 2 exx, ARC2526 (EMBL # LM655863), same data as holotype; 1 ex, ARC2529 (EMBL # LM655866), Mt. Santubong, sample 4, N01°43.884', E110°19.715', 487 m, 06-XII-2011; 2 exx, sample 5, N01°43.843', E110°19.672', 478 m, 06-XII-2011; 2 exx, sample 6, N01°43.830', E110°19.601', 375 m, 06-XII-2011; 1 ex, Mt. Santubong, 700 m, 25-III-1990; 2 exx, Bako N.P., 27-III-1990.

Sarawak (Santubong). Elevation: 487–700 m.

This species is named in honour of Alfred Russel Wallace (1823–1913) for laying the foundation of research on the Natural History of the Indo-Australian Archipelago. He spent some time at this species´ type locality where he prepared the draft of his “Sarawak Law”.

Trigonopterus wallacei Riedel, sp. n. was coded as “Trigonopterus sp. 362” by Tänzler et al. (2014).