Cissidium basale Motschulsky, 1855

Darby, Michael, 2020, A revision of Cissidium Motschulsky (Coleoptera: Ptiliidae) with seventy seven new species, European Journal of Taxonomy 622, pp. 1-188 : 140-141

Cissidium basale Motschulsky, 1855

Figs 3E , 88

Material examined

PANAMA • ♂; Barro Colorado Is ; Berlese leaves and drift among rocks of stream bed; 25 Jan. 1950; H.S. Dybas 8-147 leg.; the specimen also bears a label stating “ Cissidium basale Mots. det C. Johnson 1971 cf with 2 syntypes ”; MMUE .

Supplementary description

SIZE. Habitus ( Fig. 88A ), length 0.76 mm.

COLOUR. Dark brown shining, pubescence, legs and antennae yellow.

HEAD. With a sharp linear depression interrupted medially by a fovea behind the eyes ( Fig. 3E ), width across eyes 0.23 mm; antennomeres III–XI length 0.49 mm, III–IX length 0.25 mm, X–XI length 0.24 mm; mentum difficult to make out, submentum with two very long setae.

PRONOTUM. Length 0.24 mm, width 0.30 mm, with scattered pubescence on disc and along lateral margins; lateral margins strongly bordered, sharply angled medially, anterior corners obtusely angled, posterior corners rectangular, border on posterior margin obscured laterally and along emargination in front of the scutellum ( Fig. 88B ).

ELYTRA. Length 0.48 mm, width 0.39 mm, sparsely pubescent, length of setae as pronotum.

MESOVENTRITE. Medial extension of collar pointed; anterior margin of mid-keel wide, tapering with sinuous lateral margins directly to keel, without a clear posterior margin; keel long, parallel-sided with five setae, terminating past the midpoint of the mesocoxae; mesoventral lateral margins effaced; humeri toothed, posterior margins sinuous, long ( Fig. 88C ).

METAVENTRITE. Length 0.12 mm, width across spines 0.08 mm, with scattered setae, disc simple; posterior margins of mesocoxal borders without serrations.

WINGS. Macropterous.

Remarks

One of the three Panamanian species in this group. Distinguished by the very broad anterior margin of the mesoventral mid-keel together with the short and sharply pointed median extension of the collar.

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. 88. Cissidium basale Motschulsky, 1855. A. Habitus. B. Pronotum, × 385. C. Mesoventrite showing median process of collar, mid-keel and keel, × 710.