Cissidium pauxillum Darby, 2019

Darby, Michael, 2020, A revision of Cissidium Motschulsky (Coleoptera: Ptiliidae) with seventy seven new species, European Journal of Taxonomy 622, pp. 1-188 : 92-93

Cissidium pauxillum Darby, 2019

Fig. 59

Material examined

Holotype

MALAYSIA • Sarawak, 4 th division, Gunung Mulu National Park ; May–Aug. 1978; base comp, alluvial forest litter near laboratory; P.M. Hammond and J.E. Marshall leg., BM 1978-49; BMNH.

Supplementary description

The following description amplifies the type description of Darby (2019), by adding more details of the meso- and metaventral characters, in order to conform with the entries in the present paper.

SIZE. Habitus ( Fig. 59A ), length 0.68 mm.

COLOUR. Yellow, antennae, legs and pubescence paler yellow. HEAD. Distance across eyes 0.18 mm; antennomeres III–XI, length 0.25 mm, III–IX, length 0.15 mm, X–XI length 0.10; mentum as Fig. 4A.

PRONOTUM. Length 0.17 mm, width 0.27 mm, densely foveolate and pubescent throughout, without foveae; side margins evenly curved to rectangular hind angles, lateral margins continued along base to the angulate medial emargination opposite the scutellum ( Fig. 59B ).

ELYTRA. Length 0.37 mm, width 0.30 mm, foveolate and pubescent throughout.

MESOVENTRITE. Short, collar without reticulation though with a little medial coarse sculpturing, medial extension broadening posteriorly; mid-keel short, anterior angles almost reaching collar, posterior angles not reaching mesocoxal anterior borders, setose before junction with keel; keel tapering then narrow and parallel-sided before pointed termination at interruption of mesocoxal margins; humeri with sharply projecting teeth; mesoventral lateral margins serrate ( Fig. 59C ).

METAVENTRITE. With scattered pubescence, length 0.11 mm, disc simple, width across spines 0.09 mm, spines long, sharply pointed.

Remarks

This is the only species from Malaysia in this group which has strongly concave margins to the mesoventral mid-keel. The genitalia have not been dissected.

Figures

Fig. 59. Cissidium pauxillum Darby, 2019. A. Habitus. B. Pronotum, × 590. C. Mesoventrite showing median process of collar, mid-keel and keel, × 810.

Fig. 4. Menta and submenta. A. Cissidium petri Darby, 2015, × 1380. B. Cissidium tigrum Darby, 2015, × 1220. C. Cissidium amboroense Darby, 2015, × 1260. D. Cissidium losbanos sp. nov., × 1100. E. Cissidium triangulum Darby, 2019, × 650. F. Cissidium pilosellum sp. nov., × 1420.