Acrotrichis bidens, Darby, Michael, 2019

Darby, Michael, 2019, New Ptiliidae (Coleoptera) from Sarawak in the spirit collection of the Natural History Museum, London, European Journal of Taxonomy 512, pp. 1-50 : 34-35

Acrotrichis bidens sp. nov.

urn:lsid:zoobank.org:act:3B41E644-05C6-48F5-99B5-A128A2AC458E

Fig. 16

Diagnosis

The short metaventral termination and form of the genitalia distinguish this species.

Etymology

Named after the form of the metaventral termination between the metacoxae.

Type material

Holotype MALAYSIA-BORNEO • ♀; Sarawak, 4 th Division , Gunung Mulu National Park; 800–1700 m a.s.l.; 29 Apr. 1978; I. Hanski leg., BM 1978-524 ; pitfall trap fish bait LMR forest slope 10-12; BMNH.

Paratypes

MALAYSIA-BORNEO • 3 specs; same data as for holotype; BMNH.

Description

SIZE. Habitus ( Fig. 16A ), length 0.73 mm.

COLOUR. Dark yellowish brown, antennae and legs yellow, dorsal surface densely covered with fine overlapping yellow pubescence.

HEAD. Distance across eyes 0.29 mm; antennomeres III–XI, length 0.31 mm; mentum and submentum chaetotaxy ( Fig. 16F ).

PRONOTUM. Length 0.22 mm, width 0.47 mm, hind angles with a tiny sinuation in the lateral margin creating an acute angle (viewed from 45°).

ELYTRA. Length 0.46 mm, width 0.47 mm, clearly reticulate.

VENTRUM. Mesoventrum reticulate, without pubescence, keel obliterated anteriorly before collar, extending posteriorly to a sharp point between the mesocoxae ( Fig. 16G ). Metaventrum reticulate with scattered pubescence at lateral margins, posterior margin between metacoxae very short, with two sharp points at corners ( Fig. 16H ).

ABDOMEN. Pygidium with three teeth and a row of setae along the anterior border ( Fig. 16I ).

FEMALE GENITALIA. Spermatheca elongate ( Fig. 16E ).

MALE GENITALIA. Aedeagus narrowing to a short flat tip ( Fig. 16D ).

Remarks

The close proximity of the metacoxae makes this a marginal choice for placement in Storicricha (see below).

Figures

Fig. 16. Acrotrichis bidenssp. nov. A. Habitus. B. Hindangle of pronotum viewed at 45°. C.Antennomeres III–XI. D. Aedeagus. E. Spermatheca. F. Mentum and submentum. G. Meso- and metaventra. H. Bifid process of the metaventrum between the metacoxae. I. Pygidium