Heteromeringia nervosa, Lonsdale & Marshall, 2007

Lonsdale, Owen & Marshall, Stephen A., 2007, Revision of the New World Heteromeringia (Diptera: Clusiidae: Clusiodinae), Beiträge Zur Entomologie = Contributions to Entomology 57 (1), pp. 37-80 : 47-48

Heteromeringia nervosa sp. n.

( Fig. 56 , Map 3 )

Description

Male ( Fig. 56 )

Body length 4.1 mm. Bristles black. Two dorsocentral bristles. Ocellar bristle relatively long and well-developed. Genal bristles small and hair-like. Three fronto-orbital bristles. Arista pubescent. Male with small white circular structure anterior and ventral to anepisternal bristle. Thorax dark brown with postpronotum reddish-brown. Coxae yellow with dorsal margin of mid coxa brown. Fore femur dark brown on distal 1/5; mid femur with dark brown inner-apical spot; hind femur with dark brown apex; fore tibia with dark brown mottling (excluding base); mid tibia with well defined dark brown outer-apical spot; fore tarsi dark brown; remainder of legs light yellow. Head yellow with frons dark brown (excluding thin border along posterior, lateral and anterior margin), first flagellomere dark brown on inner face (excluding base), and back of head and posterior half of occiput dark brown. Upper 2/3 of gena and anterodorsal margin of occiput silvery tomentose; anterior margin of frons with small triangular pilose patch. Abdomen dark brown. Wing darkly clouded on distal half around R 2 2+3; remainder of wing with infuscation surrounding veins. M 1+2

ratio 6.8.

Male terminalia

Not dissected, but external terminalia nearly twice as large as those of any other Heteromeringia (that is, terminalia wider than tergite 6). Epandrium approximately as wide as long and half as high as wide. Cerci small and triangular. Surstylus half length of epandrium with basal 2/5 parallel, distal 3/5 triangular, dorsal margin straight with apex slightly rounded, posterodistal margin slightly concave and inset, and inner face covered with short pointed bristles.

Female

Unknown.

Etymology

The specific name refers to the characteristic wing veins, which are surrounded by a thin infuscation.

Holotype: COSTA RICA. Puntarenas: Monteverde , 1600 m, 22-27.ii.1991, B.J. Sinclair, at lights (1 , CNCI).

Comments

Heteromeringia nervosa and H. volcana are both restricted to Costa Rica, and may form a natural group with H. fumipennis on the basis of reduced pilosity on the male frons and a predominantly yellow fore femur. Heteromeringia nervosa can be separated from other Heteromeringia by its characteristic wing pattern and its very large external male terminalia. Th e colouration of the wing and legs are similar to that of the nearctic H. nitida , but the wing pattern is slightly different medially and the terminalia (particularly the surstylus) are undoubtedly different.

Heteromeringia volcana , in comparison, has male terminalia similar to those of H. nigripes , which is also known from Costa Rica, but the genitalia differ as mentioned in the description. Furthermore, the palpus is yellow, the legs are predominantly yellow, the gena is yellow ventrally, the bristles are brown and the ocellar bristles are not as well developed.

Figures

Map 3: Distributions of Heteromeringia apholisapholis sp. n., H. zophinazophina sp. n., H. decora sp. n., H. nervosanervosa sp. n., H. volcanavolcana sp. n., H. nanellananella sp. n., H. nigrifrons KERTESZ, and H. fucata HENDEL.

Figs 54-63: wings; 54: Heteromeringia fucata HENDEL, 1936, female; 55: H. nitida JOHNSON, 1913, female; 56: H. nervosanervosa sp. n., male; 57: H. fumipennis MELANDERMELANDER & ARGO, 1924, female; 58: H. decoradecora sp. n., female; 59: H. czernyi KERTESZ, 1903, female; 60: H. lateralislateralis sp. n., female; 61: H. flavifrons HENNIG, 1938, female; 62: H. quadriseta sp. n., male; 63: H. medianamediana sp. n., male.