Cissidium angusi, Darby, 2020

Darby, Michael, 2020, A revision of Cissidium Motschulsky (Coleoptera: Ptiliidae) with seventy seven new species, European Journal of Taxonomy 622, pp. 1-188 : 100-101

Cissidium angusi sp. nov.

urn:lsid:zoobank.org:act:A1B4A3E6-D811-4560-87A1-D36B12D2391B

Fig. 63

Etymology

Named after my colleague Dr Robert Angus.

Material examined

Holotype

BRAZIL • ♀; Bocaiuva , Parana; Dec. 1963; F. Plaumann leg.; FMNH.

Paratypes

BRAZIL • 4 ♀♀; same collection data as for holotype; one mounted verso, one mounted as a slide; MMUE, BMNH.

Description

SIZE. Habitus ( Fig. 63A ), length 0.95 mm.

COLOUR. Yellow brown, head slightly darker, pubescence, legs and antennae slightly paler.

HEAD. With a clearly marked linear depression behind the eyes, width across eyes 0.23 mm; antennomeres III–XI length 0.42 mm, III–IX length 0.25 mm, X–XI length 0.17 mm; mentum as Fig 4E though sides slightly more sinuous.

PRONOTUM. Length 0.24 mm, width 0.32 mm, pubescent, without foveae; side margins rounded and then concave to acute hind angles, bordered, the border extending along the posterior margin to the medial emargination opposite the scutellum ( Fig. 63B ).

ELYTRA. Length 0.55 mm, width 0.47 mm, pubescent, length of setae as pronotum.

MESOVENTRITE. Medial extension of collar widening posteriorly; anterior margin of mid-keel wider than posterior, posterior margin not reaching anterior margin of mesocoxal cavities; keel with a series of ± eight setae tapering to point above the interruption of the mesocoxal borders; mesoventral lateral margins without serrations; humeri toothed ( Fig. 63C ).

METAVENTRITE. Length 0.17 mm, width across spines 0.13 mm, with scattered setae, disc simple; posterior margins of mesocoxal cavities not serrate.

WINGS. Macropterous.

GENITALIA. Female spermatheca globular. Male not known.

Remarks

One of the three Brazilian species in this group, and distinguished by the parallel-sided median extension of the mesoventral keel together with the wide anterior angles of the mid-keel and the long tapering keel.

Figures

Fig. 63. Cissidium angusi sp. nov. A. Habitus. B. Pronotum, × 520. C. Mesoventrite showing median process of collar, mid-keel and keel, × 1040.

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.