Ptomaphaminus microphallus Schilthuizen & Perreau

Schilthuizen, Menno, Perreau, Michel & Njunjic, Iva, 2018, A review of the Cholevinae from the island of Borneo (Coleoptera, Leiodidae), ZooKeys 777, pp. 57-108 : 91

Ptomaphaminus microphallus Schilthuizen & Perreau sp. n. Figures 11f, 12y, z, 13q

Material.

Holotype: Malaysia, Sabah, Kinabalu Park, Poring Hot Springs, 6°02.894'N, 116°41.957'E, 625 m elev., in baited pitfall traps, 15-20.ix.2012, (leg. M. Schilthuizen, Crocker Range / Kinabalu Expedition), 1 male in RMNH (RMNH.INS.1086291). Paratypes: Sabah. Kinabalu Park, Poring Hot Springs, 6°02.894'N, 116°41.957'E, 625 m elev., in baited pitfall traps, 15-20.ix.2012 (leg. M. Schilthuizen, Crocker Range / Kinabalu Expedition), 1 male paratype in RMNH (RMNH.INS.1086292).

Description.

Length: 1.2 mm. General colour dark brown; the tarsi and two first antennomeres lighter. Winged. Pronotum 1.55 times as wide as long. Elytra 1.15 times as long as wide. Male protarsi 0.6 times as wide as the protibia. Spiculum gastrale of the male genital segment apically dilated into a short discoid expansion (Figure 13q). Aedeagus very small, 5.5 times shorter than the body length. Lateral sides regularly arcuate in dorsal view (Figure 12y), flattened in the middle and with a short ventrally retroverted expansion in lateral view (Figure 12z). On each side, six latero-preapical pointing ventral setae and one apical seta pointing forward. Internal stylus of the aedeagus weakly sinuate.

Differential diagnosis.

The female is unknown, but the male aedeagus shares several features with other species, such as P. marshalli , P. nanus , and P. alabensis (i.e., a relatively short aedeagus with retroverted hook). However, P. microphallus is unique among Borneo Ptomaphaminus by its extremely short (0.22 mm) aedeagus.

Habitat and distribution.

Known from the type locality, in Kinabalu Park, Sabah, Malaysia.

Remarks.

Female unknown.

Etymology.

Named for the relatively small male genitalia.