Monolepta bivittata, Lei & Xu & Yang & Nie, 2021

Lei, Qi-long, Xu, Si-yuan, Yang, Xing-ke & Nie, Rui-E, 2021, Five new species of the leaf-beetle genus Monolepta Chevrolat (Coleoptera, Chrysomelidae, Galerucinae) from China, ZooKeys 1056, pp. 35-57 : 35

Monolepta bivittata sp. nov.

Figs 21-27

Type material.

Holotype: China • ♂; Zhejiang, Taishun, Wuyanling Nature Reserve station by light; 800 m; 1-VIII-2005; Liu Ye leg. (IZAS). Paratypes: China • 3♂♂; Zhejiang, Taishun, Wuyanling Nature Reserve station, at light; 800 m; 1-VIII-2005; Liu Ye leg. (IZAS).

Description.

Length: 3.0-3.6 mm, width: 1.5-1.7 mm. Holotype: length 3.6 mm, width 1.7 mm.

Head, dorsal and ventral side of prothorax, and legs yellowish brown; mouthparts, scutellum, ventral side of mesothorax and metathorax black; antennae black, except segments 1-3 yellowish brown; elytra and abdomen pale yellow, basal and postmedian area of elytra with transverse black stripe.

Vertex convex, with sparsely distributed punctures; frontal tubercle developed, trapezoid, glabrous and without punctures; antennae reach half of body, 1st segment arc-shaped, length ratio of segment 2nd and 3rd 15: 16, length ratio of 4thand combination of 2nd and 3rd 34: 31.

Pronotum about 1.5 times as broad as long; disc slightly convex, shallowly depressed on each side, punctures unapparent and sparsely distributed.

Scutellum triangular, smooth and impunctate. Elytron about 1.5 times as long as broad; basal part wider than pronotum, humeral angle obvious; punctures evenly distributed, space between punctures is about 2 times as diameter of puncture, each puncture with seta; epipleuron strongly narrowed after basal 1/3, disappearring at beginning of apex. Ventral side of mesothorax, metathorax and abdomen covered with long hairs.

Male. Last ventrite of male with trilobite concavities. Width and length ratio of median apical lobe 1.4 (apex width to length), 1.5 (basal width to length) (Fig. 24 ). Aedeagus: ratio of length to width around 4:3; gradually and slightly tapering from base to near apex then abruptly constricted in distal 1/5 in lateral view; apex rounded and slightly pointed (Figs 25 , 27 ). Tectum broad, long, reaching to apex of aedeagus (Fig. 25 ).

Etymology.

The specific epithet bivittatus, - a, - um (meaning ‘bivittate’, 'having two bands or stripes or vittae’) is a New Latin adjective formed from the Latin prefix bi - (a shortened form of bis, ‘twice’) and the Latin adjective vittatus, - a, - um ( ‘banded’); it refers to the two transverse black stripes on the elytra of this species, a character which distinguishes this species from all other species in the genus.

Distribution.

China: Zhejiang.

Diagnosis.

This species is similar to M. leechi Jacoby, 1890, M. maana Gressitt & Kimoto, 1963, and M. liui Gressitt & Kimoto, 1963. The main differences are the following: the abdomen of M. leechi is black and the apex of the aedeagus is sharp, whereas the abdomen of M. bivittata sp. nov. is pale yellow and the apex of the aedeagus is blunt. The space between the punctures on the elytra of M. maana is equal to the diameter of the punctures, whereas in M. bivittata sp. nov., it is about twice the diameter of the punctures. The mid- and hind-legs of M. liui are dark brown, whereas the legs of M. bivittata sp. nov. are yellowish brown.

Figures

Figures 21 - 27. Monolepta bivittata sp. nov. (holotype) 21 dorsal view 22 lateral view 23 frontal view 24 ventral view of 5 th ventrite, male 25 aedeagus, dorsal view 26 ditto, lateral view 27 ditto, ventral view. Scale bars: 1 mm.