Monolepta bruneiensis, Hazmi & Wagner, 2022

Hazmi, Izfa Riza & Wagner, Thomas, 2022, Revision of Monolepta Chevrolat, 1836 from the Sundaland area (Coleoptera: Chrysomelidae: Galerucinae), Bonn zoological Bulletin 71 (2), pp. 139-176 : 164-165

Monolepta bruneiensis sp. nov.

urn:lsid:zoobank.org:act:AE00CBE3-4EC8-4F4D-A7A0-08C866CC2279

Figs 43–45

Type material. Holotype: ♂ “ Brunei, E 115 7′N 4 34′, Kuala Belalong FSC, Dipterocarp forest , Dryobalanops beccarii / BM (NH) 1991-173 / Aerial Malaise 1A 260 m, alt. 2.vi.91 / N. Mawdsley. NM 175” ( BMNH; Fig. 43 ). Type locality: 4º34′ N / 115º07′ E . – Paratypes: 4 ex., same data as holotype ( BMNH) .

Etymology. The name of the new species refers to the state where it exclusively occurs.

Description

Total length. 3.75–4.70 mm (mean 4.26 mm; n = 6).

Head. Very finely punctuated, entirely brownish-red and shining. Labrum and mandible as head, apically a bit darker. Eyes very large. Antenna slender, extending almost to the middle of elytra, blackish and only three basal antennomeres yellow-brownish ( Fig. 44A ) or the terminal antennomeres more brownish ( Fig. 43b ). Second antennomere significantly longer than third; ratio length of second to third antennomere 1.00–1.50 (mean 1.25); ratio length of third to fourth antennomere 0.25– 0.29 (mean 0.27; Fig. 44B ).

Thorax. Pronotum finely punctuated, entirely brown- ish-red, broad. Pronotal width 1.15–1.30 mm (mean 1.24 mm), ratio length to width 0.56–0.58 (mean 0.57). Scutellum, meso- and metathorax brownish-red. Elytra entirely yellow to yellowish-brown. Elytral length 2.90– 3.55 mm (mean 3.19 mm), maximal width of both elytra together 2.20–2.70 mm (mean 2.46 mm), ratio of maximal width of both elytra together to length of elytron 0.75–0.79 (mean 0.77; Fig. 44A ). Legs yellowish-brown.

Abdomen. Yellowish-brown.

Male genitalia. Median lobe nearly parallel-sided and slender. Tectum long and broad. Median spiculae broad, flat with comb-like apex, overlapping in dorsal view ( Fig. 44 Ca), lateral spiculae as simply slender spikes, ventral spiculae slender curved hook ( Fig. 44C ).

Female genitalia. Spermatheca with spherical nodulus, short middle part and long and slender cornu ( Fig. 44D ). Bursa sclerites weakly sclerotized and hardly visible.

Diagnosis. Monolepta bruneiensis sp. nov. is most similar in body colouration to M. mentaweiensis ( Figs 29A , 44A ). Both species possess a brownish-red pronotum and yellowish elytra, but M. mentaweiensis , additionally has a brownish-red transverse basal band on the elytra (in some old specimens, this band is a bit fainted) lacking in M. bruneiensis sp. nov.. External differences are the very short third antennomere in M. bruneiensis sp. nov. (mean of ratio length second to third antennomere 1.25) while it is longer in M. mentaweiensis (mean of same ratio 0.80; Figs 29B , 44B ), both species can be also differentiated by size (total length M. bruneiensis sp. nov. 3.75–4.70 mm; M. mentaweiensis 4.90–6.25 mm), and in all doubtful cases, the genitalic characters allow an easy identification.

Distribution. Only recorded from Brunei in North- West Borneo ( Fig. 45 ).

Figures

Fig. 43. Type material of Monolepta bruneiensis sp. nov., holotype (BMNH).

Fig. 44. Monolepta bruneiensis sp. nov. A. Colour pattern. B. Basal antennomeres. C. Median lobe, a. dorsal, b. lateral, c. ventral, without endophallic structures. D. Spermathecae. E Bursa-sclerites, a. dorsal, b. ventral.

Fig. 45. Distribution of Monolepta bruneiensis sp. nov., and M. emphatbulat sp. nov.

Fig. 29. Monolepta mentaweiensis (Jacoby, 1896). A. Colour pattern. B. Basal antennomeres. C. Median lobe, a. dorsal, b. lateral, c. ventral, without endophallic structures. D. Spermathecae. E. Bursa-sclerites, a. dorsal, b. ventral.