Holotype, male (Fig. 44a). Length 2.06 mm. Color of antennae light ferruginous, remainder dark ferruginous to black. Body in dorsal aspect with marked constriction between pronotum and elytron; with distinct constriction in profile. Rostrum dorsally dull, rugulose; with median ridge and pair of indistinct submedian ridges, intervening furrows punctate, sparsely squamose with small suberect scales; epistome simple. Pronotum anterolaterally very weakly angularly projecting; with distinct subapical constriction; disk coarsely punctate, each puncture containing minute scale; interspaces dull, microreticulate; indistinct median ridge subglabrous. Elytra with striae deeply impressed, each with row of minute transparent scales; intervals costate to subcarinate, microreticulate; interval 7 swollen subapically, laterally projecting. Profemur edentate, meso- and metafemur ventrally with denticle. Metafemur subapically with stridulatory patch and transverse rows of denticles. Abdominal ventrite 5 with shallow impression. Penis (Fig. 44b) with body in profile markedly curved ventrad; basal half flattened, in dorsal aspect sides subparallel; towards apex slightly widened; apex with median, subtriangular extension; transfer apparatus flagelliform, ca. 1.3 × as long as body; apodemes 2.2 × as long as body; ductus ejaculatorius without bulbus. Intraspecific variation. Length 1.96–2.40 mm. Color of body black or ferruginous. Female rostrum dorsally subglabrous, with pairs of lateral and submedian furrows; epistome simple. Pronotum with anterolateral knobs indistinct or more distinctly projecting. Female abdominal ventrite 5 flat.

Holotype (MZB): ARC0266 (EMBL # LM655457), East Sumatra, Lampung Prov., Bawang, Pedada Bay, Mt. Tanggang, sample 2, S05°43.947', E105°06.480', 659 m, 09-VIII-2006. Paratypes (MZB, SMNK, ZSM): E-Sumatra, Lampung Prov.: 1 ex, ARC0267 (EMBL # LM655458), same data as holotype; 1 ex, ARC0274 (EMBL # LM655465), Bawang, Pedada Bay, Mt. Tanggang, sample 3, S05°43.938', E105°06.440', 673 m, 09-VIII-2006; 1 ex, Bawang, Pedada Bay, Mt. Tanggang, sample 4, S05°43.871', E105°06.393', 744 m, 09-VIII-2006; 1 ex, Bukit Barisan Selatan N.P., Kota Agung, Sukaraja, sample 5, S05°31.044', E104°25.664', 562 m, 02-V-2012; 1 ex, ARC2731 (EMBL # LM655987), Bukit Barisan Selatan N.P., Kota Agung, Sukaraja, sample 8, S05°33.032', E104°25.985', 421 m, 02-V-2012; 2 exx, ARC2732 (EMBL # LM655988), ARC2733 (EMBL # LM655989), Bukit Barisan Selatan N.P., Liwa, sample 1, S05°04.409', E104°03.265', 670 m, 04-V-2012; 1 ex, Bukit Barisan Selatan N.P., Liwa, sample 6, S05°04.753', E104°03.183', 809 m, 05-V-2012; 1 ex, ARC2734 (EMBL # LM655990), Bukit Barisan Selatan N.P., Liwa, sample 7, S05°04.958', E104°03.379', 813 m, 05-V-2012; 1 ex, Bukit Barisan Selatan N.P., Liwa, sample 8, S05°05.015', E104°03.442', 801 m, 05-V-2012.

Lampung Prov. (Bukit Barisan Selatan N.P., Pedada Bay). Elevation: 421–813 m.

This epithet is based on the Indonesian province of Lampung.

Trigonopterus lampungensis Riedel, sp. n. was coded as “Trigonopterus sp. 301”.