Cissidium bilineatum, 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 : 105-106

Cissidium bilineatum sp. nov.

urn:lsid:zoobank.org:act:E3934680-B3BE-4C64-87A4-FE0BEEF8896F

Figs 3H , 6A , 66

Etymology

Named after the linear depressions on the pronotum

Material examined

Holotype

MALAYSIA • ♂; E Johore Sedili, Jason’s Bay , coastal swamp forest; 13 Oct. 1963, very wet litter; D.H. Murphy leg.; No 82; FM(HD) # 50.34; FMNH.

Paratypes

MALAYSIA • 1 ♂, 2 ♀♀; same collection data as for holotype; 1 ♀ mounted verso; MMUE, BMNH.

Additional material

MALAYSIA • 1 ♂; Sabah, Sandakan Distr., Sapagaya Forest Res.; 27 Jul. 1980; logged dipterocarp forest; R.F. Inger and D.D. Davis leg.; lacking antennae and with one elytron re-attached; MMUE. This specimen, not listed as a paratype, may be this species. It is much darker than the type series but in all

other respects similar, particularly in having a very setose head and patches on the mesoventral collar without reticulation.

Description

SIZE. Habitus ( Fig. 66A ), length 0.68 mm.

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

HEAD. Densely setose and foveolate ( Fig. 3H ); width across eyes 0.21 mm; antennomeres III–XI length 0.33 mm, III–IX length 0.21 mm, X–XI length 0.12 mm globular; mentum as Fig. 4A.

PRONOTUM. Length 0.21 mm, width 0.31 mm, pubescence more outstanding than on elytra, with two linear depressions reaching almost to the midpoint of the sclerite; side margins ± sharply angled then sinuate to obtuse hind angles, bordered, the border extending along the entire posterior margin including the emargination opposite the scutellum ( Fig. 66B ).

ELYTRA. Length 0.44 mm, width 0.40 mm, more densely pubescent than pronotum, pubescence slightly shorter.

MESOVENTRITE. Medial extension of collar narrow either side of semi-circular impressions in collar then widening posteriorly; mid-keel posterior corners not reaching anterior margin of mesocoxal borders; keel with a series of ± nine setae, almost parallel to a rounded tip between the mesocoxae; mesoventral lateral margins serrate in posterior half; humeri strongly toothed ( Fig. 66C ).

METAVENTRITE. Length 0.16 mm, width across spines 0.10 mm, with scattered setae, disc plain; posterior margins of mesocoxal cavities serrate.

WINGS. Macropterous.

GENITALIA. Male aedeagus as Fig. 6 Fa–b. Female spermatheca ( Fig. 6A ).

Remarks

Distinguished from C. visendum sp. nov., the only other Cissidium recorded from Malaya in this group, by the presence of the linear depressions on the pronotum.

Figures

Fig. 3. Figures to show differences in morphological features of head between eyes. A. Cissidium upiense sp. nov., × 565. B. Cissidium sueae sp. nov., × 480. C. Cissidium delicatum sp. nov., × 1060. D. Cissidium foveolatum Johnson, 1982, × 730. E. Cissidium basale Motschulsky, 1855, × 385. F. Cissidium ibicarense sp. nov., × 505. G. Cissidium eciton sp. nov., × 650.

Fig. 6. Figures to show genitalia types. – Spermathecae. A. Cissidium bilineatum sp. nov. B. Cissidium amboroense Darby, 2015. C. Cissidium sawadai Darby, 2015. D. Cissidium arcuatum sp. nov. E. Cissidium murphyi sp. nov. – Aedeagi. F. Cissidium petri Darby, 2015. G. Cissidium clareae sp. nov. H. Cissidium fraternum sp. nov. I. Cissidium tigrum Darby, 2015. J. Cissidium apterum sp. nov. K. Cissidium brachypterum sp. nov. L. Cissidium greensladei sp. nov. M. Cissidium kolombangaricum sp. nov. N. Cissidium mindanao sp. nov.

Fig. 66. Cissidium bilineatum sp. nov. A. Habitus. B. Pronotum, × 395. C. Mesoventrite showing median process of collar, mid-keel and keel, × 1140.

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.