Monolepta ranuensis sp. nov.

urn:lsid:zoobank.org:act:

Figs 26, 57–58

Type material. Holotype: “ Sulawesi Tengah, Nr. Morowali, Ranu River Area, 27.I.–20.IV.1980, S. L. Sutton & C. J. Rees; M. J. D. Brendell, B. M. 1980-281 ” (BMNH; Fig. 57) . – Paratypes. 108 ex., same data as holotype (BMNH). Type locality: 6º14′ S / 106º49′ E .

Etymology. The name refers to the type locality, Ranu River in Sulawesi.

Description

Total length. 3.25–3.70 mm (mean 3.44 mm; n = 10).

Head. Finely punctuated, yellowish, with deep suture between antennal sockets, labrum and mandible yellowish-brown. Antenna very slender, extending to the middle of the elytra, yellow, last antennomere darker (Figs 57b, 58A). Second antennomere on average shorter than third; ratio length of second to third antennomere 0.67–1.00 (mean 0.85); ratio length of third to fourth antennomere 0.43–0.50 (mean 0.42; Fig. 58B).

Thorax. Pronotum yellow, broad, shining and with shallow depression in the middle, comparatively coarsely punctuated. Pronotal width 0.95–1.00 mm (mean 0.97 mm), ratio length to width 0.63–0.65 (mean 0.64). Scutellum, meso- and metathorax yellow, as elytron that is coarsely punctuated and shining. Elytral length 2.35– 2.60 mm (mean 2.43 mm), maximal width of both elytra together 1.70–1.90 mm (mean 1.74 mm), ratio of maximal width of both elytra together to length of elytron 0.69–0.73 (mean 0.71; Fig. 58A). Legs yellow.

Abdomen. Yellowish.

Male genitalia. Median lobe lanceolate, becoming slightly towards apex. Median spiculae as few stronger spines, often slightly curved in dorsal view, on base with two horn-shaped structures (Fig. 58 Cb), lateral spiculae slender with two small spines apically, ventral spiculae weakly sclerotized and hardly visible or absent (Fig. 58C).

Female genitalia. Spermatheca with small spherical nodulus and long and slender middle part and cornu (Fig. 58D). Bursa sclerites broad, nearly of same size with spiny margins (Fig. 58E).

Diagnosis. Monolepta ranuensis sp. nov. is with a total length of 3.25–3.70 mm the smallest “true” species of Monolepta from Sundaland area. Somewhat similar is the also unicolorous, but reddish-brown M. sulawensis sp. nov. that is of similar size and occurs syntopic at the same place on Sulawesi. In doubtful cases, the genital characters of both sexes allow a clear identification (Figs 58C–E, 60C–E). Also, the shallow transverse pronotal depression, and the elytral punctuation is characteristic for M. sulawensis sp. nov. There a several further small completely yellow species described in Monolepta (and probably even not yet described) in the region, and in many cases the genitalic dissection only allows an allocation to genus and species.

Distribution. Only recorded from the type locality in Central-Eastern Sulawesi (Fig. 26).