Nanomela, Leschen & Reid & Nadein, 2020

Leschen, Richard A. B., Reid, Chris A. M. & Nadein, Konstantin S., 2020, Generic Review of New Zealand Chrysomelinae (Coleoptera: Chrysomelidae), Zootaxa 4740 (1), pp. 1-66 : 52

Nanomela mainland group

( Figs 10A,B,E , 12A , 14 A-C, 15B,C, 16A,C,E)

Diagnosis. Head relatively long and narrow. Eye consisting of a one to two ommatidia. Antennae with antennomere 8 smaller than 7th, distance between antennal socket and margin of eye is equal to diameter of socket. Posterior margin of the pronotum evenly rounded. Elytra with 7 distinct, but weakly impressed striae. Aedeagus with median lobe subrounded to weakly arrow-shaped.

Description. Length 1.30–1.55 mm. Body widely-elliptic to somewhat narrowed, slightly dorsoventrally flattened (greatest depth 0.60–0.80 mm); entirely reddish-brown. Vertex very wide, feebly convex, inner margin of eye without a small seta. Head relatively long and narrow. Eyes very small, round, consisting of 1 large ommatidium. Frons large and elongate-trapezoidal, nearly as long as wide, anterior margin straight. Antennae with antennomere 8 smaller than 7 th (ratio of antennomere lengths variable but generally: 0.6/0.3/0.3/0.3/0.3/0.2/0.3/0.3/0.4/0.5/0.8), distance between insertion and margin of eye is equal to diameter of insertion. Pronotum transverse (1.50–1.80 x wider than long), posterior margin of pronotum evenly rounded. Elytra elongate (2.87–3.33 x longer than pronotal length) and narrow (1.36–1.64 x the greatest elytral width); punctation striate, punctures arranged in 7 striae, epipleura narrow to moderately wide, flat, weakly inclined, feebly visible in lateral view. Spermatheca with rather short and thick collum and nodulus, strongly curved, collum with obtuse apex, duct comparatively long. Median lobe of aedeagus in ventral view straight, basal opening narrower than apical opening, the lobe gradually narrowed from apex to base, apical fourth widened, apex subrounded, median lobe inside with long, straight, and thin flagellum that curved in basal third.

Comments. These species differ from Nanomela tiniheke by the head which is longer and narrower, with an elongated frons, the eyes smaller with fewer facets, the pronotal posterior margin evenly rounded, the elytral apices wider and not elongate, and the spermatheca with an obtuse collum and long duct.

Distribution. South Island and Stewart Island.

Figures

FIGURES 10A–F. Habitus of Nanomela spp.; A, Nanomela sp., dorsal, length 1.5 mm; B, Nanomela sp., ventral, length 1.5 mm; C, Nanomela tiniheke, dorsal, length 2.2 mm; D, Nanomela tiniheke, ventral, length 2.2 mm; E, Nanomela sp., lateral, length 1.5 mm; F, Nanomela tiniheke, ventral, length 2.2 mm.

FIGURES 12A–N. Habitus and genitalia; A, Nanomela sp., dorsal, scale = 1 mm; B, Nanomela tiniheke, dorsal, scale = 1 mm; C, Maurodus maculatus, aedeagus, dorsal view; D, Maurodus maculatus, aedeagus, lateral view; E, Maurodus occiduus, aedeagus, dorsal view; F, Maurodus occiduus, aedeagus, lateral view; G, Maurodus nunni, aedeagus, dorsal view; H, Maurodus nunni, aedeagus, lateral view; I, Maurodus supernus, aedeagus, dorsal view; J, Maurodus supernus, aedeagus, lateral view; K, Zeaphilon marskeae, aedeagus, dorsal view; L, Zeaphilon marskeae, aedeagus, lateral view; M, Zeaphilon mirandum, aedeagus, dorsal view; N, Zeaphilon mirandum, aedeagus, lateral view.

FIGURES 14A–D. Ventral SEMs of Nanomela spp.; A, Nanomela sp., body; B, Nanomela sp., prothorax; C, Nanomela sp., meso-, meta-, and abdominal ventrites; D; Nanomela tiniheke, meso- and metaventrite.