Holotype, male (Fig. 19a). Length 3.00 mm. Color of legs and antennae ferruginous; remainder black, pronotum and elytron bronze-coppery. Body in dorsal aspect with marked constriction between pronotum and elytron; in profile convex. Rostrum with median ridge; pair of submedian ridges converging and uniting on forehead; intervening furrows each with sparse row of suberect elongate scales; in apical third coarsely punctate; epistome with transverse, angulate ridge. Pronotum with sides subparallel, slightly converging; with distinct, subapical constriction; disk coarsely punctate, reticulate; each puncture containing brown recumbent seta; with pair of submedian impressions, medially swollen, with indistinct median ridge. Elytra with humeri swollen, laterally projecting; striae distinct, deeply impressed; intervals costate, punctate; punctures near base coarse and dense; near middle transverse band polished. Profemur simple; meso- and metafemur with anteroventral ridge forming large, acute tooth. Metafemur subapically with stridulatory patch. Dorsal tibial edge subbasally with indistinct angulation. Abdominal ventrite 5 flat, densely punctate, with erect setae. Penis (Fig. 19b) with sides of body subparallel; apex rounded, with fringe of conglutinate flattened setae, interrupted by glabrous median notch; transfer apparatus compact; apodemes 2.0 × as long as body; ductus ejaculatorius without bulbus. Intraspecific variation. Length 2.72–3.05 mm. Bronze color of pronotum and elytron with slightly greenish or reddish lustre. Female body more slender. Female rostrum dorsally punctate-rugose, with median and pair of submedian subglabrous costae; epistome simple. Female elytron with humeri less prominent, with subapical constriction and apex extended, suture with notch. Female abdominal ventrite 5 with sparse subrecumbent setae.

Holotype (MZB): ARC2235 (EMBL # LM655691), East Nusa Tenggara Prov., Flores, Labuhan Bajo, Tebedo, sample 1, S08°29.848', E119°59.633', 525 m, lowland forest, 14-III-2011. Paratypes (MZB, SMNK): Flores, Labuhan Bajo: 3 exx, ARC2233 (EMBL # LM655689), ARC2234 (EMBL # LM655690), same data as holotype; 1 ex, Roe, sample 4, S08°35.442', E120°00.366', 785 m, thick litter under Ficus-tree, 13-III-2011; 1 ex, ARC2215 (EMBL # LM655671), Roe, earthworm-dominated habitat, sample 1, S08°36.540', E120°01.871', 955 m, 13-III-2011.

East Nusa Tenggara Prov., Flores (Labuhan Bajo). Elevation: 525–955 m.

This epithet is based on the Latin adjective cuprescens (coppery).

Trigonopterus cuprescens Riedel, sp. n. was coded as “Trigonopterus sp. 347”.