A revision of Cissidium Motschulsky (Coleoptera: Ptiliidae) with seventy seven new species Darby, Michael European Journal of Taxonomy 2020 2020-04-02 622 1 188 8XXRY Darby, 2019 Darby 2019 [585,1003,467,494] Insecta Ptiliidae Cissidium GBIF,CoL Animalia Coleoptera 133 134 Arthropoda species triangulum   Figs 4E, 85    Material examined    Holotype MALAYSIA• Sarawak, Mulu; pitfalls in alluvial forest;  Mar. 1978; N.M. Collinsleg.; genitalia not dissected; BMNH.    Supplementary description The following description amplifies the typedescription of Darby (2019), in particular by adding more details of the meso- and metaventral characters, in order to conform with the entries in the present paper. SIZE. Habitus ( Fig. 85A), length 0.79 mm.   Fig. 85.  Cissidium triangulum Darby, 2019. A. Habitus. B. Pronotum, × 555. C. Mesoventrite showing median process of collar, mid-keel and keel, × 575. COLOUR. Yellow brown, antennae, legs, and pubescence yellow. HEAD. Distance across eyes 0.22 mm; antennomeres III–XI, length 0.31 mm; mentum triangular the anterior margin much longer than the basal, stipes also triangular, broadest at base ( Fig. 4E). PRONOTUM. Length 0.19 mm, width 0.28 mm, pubescent, shallowly foveolate; sides rounded then straight before rectangular hind angles, border crenulate, not continuing along posterior margin, median emargination angulate ( Fig. 85B). ELYTRA. Length 0.41 mm, width 0.34 mm, pubescent, the pubescence slightly longer than on the pronotum, shallowly foveolate. MESOVENTRITE. Median extension of collar parallel-sided, short, mid-keel setose and rugose before keel; keel narrow, tapering to a point at the base of the mesocoxae; mesoventral lateral margins almost straight before turning to meet mesocoxae, then obscured; humeri barely toothed ( Fig. 85C). METAVENTRITE. With scattered pubescence throughout, disc plain, length 0.14 mm, distance across spines 0.08 mm; mesocoxal posterior margins without serrations.    Remarks The only species of  Cissidiumfrom Sarawakin this group. 2609493626 1978-03 pitfalls in alluvial forest BMNH N. M. Collins Malaysia Mulu 133 134 1 Sarawak holotype