Chimarra aculeata, Blahnik & Arefina-Armitage & J, 2012

Blahnik, Roger J., Arefina-Armitage, I. & J, Brian, 2012, The Genus Chimarra Stephens (Trichoptera: Philopotamidae) in Vietnam, Insecta Mundi 2012 (229), pp. 1-25 : 4-6

Chimarra aculeata sp. n.

( Figure 1 )

Diagnosis. This species is possibly most similar to C. uncula Mey. Both species have paired spinelike projections from dorsolateral margins of segment IX and also a modified tergum VIII, with a mesal invagination and accompanying spines. The differences, however, are considerable. The armature of tergum VIII is especially distinctive in C. aculeata in that the dorsal margin has a distinctive pair of brushes composed of many spines bordering the mesal invagination; also, the apices of the resulting lobes each have a small tassel of spines. The shape of the inferior appendages is also quite different in the 2 species.

Description. Forewing length (male) 6.1 mm. Color (in alcohol) yellowish-brown. Head elongate (postocular parietal sclerite extended behind eye). Mesoscutellar setal wart pear-shaped, with usual anterior suture. Maxillary palps with 1 st segment very short, 2 nd segment relatively elongate (nearly as long as segment 3), 3 rd segment elongate, subequal to segment 5, 4 th segment short. Tarsi of males highly modified, tarsal claws enlarged and sinuous, asymmetric in length and curvature. Forewing with Rs deflected (curved toward anal margin) and weakly, sinuously inflected before base of discal cell; veins at base of discal cell not or hardly swollen, length of discal cell about 3 times width; r-m and m cross-veins hyaline (unpigmented), s not hyaline, s and r-m linearly aligned, m distinctly proximal; anal veins without apical fork (2A and 3A both apparently looped to 1A). Hind wing with Sc and R

1

narrowly separated, not fused.

Male genitalia: Segment VIII with sternum very short, tergum highly modified; tergum, as viewed laterally, with ventral margin about 2 times length of sternum, dorsum of tergum about 2 times length at base, narrowing and acute posteriorly, apex with projecting tract of spinose setae, setae somewhat mesally directed, as viewed dorsally; tergum, as viewed dorsally, with deep, more or less Vshaped mesal emargination, emargination extending almost to anterior margin, lateral margins of emargination with dense, leaf-shaped tract of spinose setae, tract narrow at base, tapering, acuminate apically. Segment IX unsclerotized dorsally, with distinct, very short dorsolateral apodemes on anterior margin; as viewed laterally, with anterior margin extending nearly linearly from apodemes, anteroventral margin not produced (truncate as viewed dorsally or ventrally); dorsolateral margins of tergum, on either side, with posteriorly projecting, spine-like process, extending about as far as lobe of tergum VIII, processes slightly mesally curved as viewed dorsally; width of segment below processes relatively short (anterior and posterior margins narrowly separated), posterior margin lengthened below preanal appendages, angulate at about level of inferior appendages; ventral process very short, subtriangular, broadest basally, projecting ventrally. Tergum X with lateral lobes moderately elongate, simple in structure; in lateral view, linear with rounded apex, in dorsal view with slight bulge on lateral margin at about middle, apices rounded; lobes with numerous sensilla, almost uniformly distributed. Mesal lobes of tergum X short, digitate, weakly sclerotized, posteriorly directed, forming about 45 degree angle with lateral lobe, each lobe (apparently) with 3 minute sensilla, 2 apically and 1 at midlength on lateral margin. Preanal appendages very small and rounded, somewhat flattened laterally, fused basally to posterior margin of segment IX. Inferior appendages, as viewed laterally, moderately elongate, linear, uniform in width, subtruncate apically; as viewed ventrally, with lateral margins rounded, mesal margins subparallel in basal half, narrowing apically, apices rather broadly rounded; appendages, as viewed caudally, with pair of minute sclerotized spine-like projections or cusps on mesal margin. Phallotheca relatively short, tubular, with usual basal expansion. Endotheca apparently short, with paired tracts of short spines. Phallotremal sclerite complex prominent, extending over half length of phallotheca, composed of ring structure with very short, paired, spinose ventral “rods”; ring open dorsally, on each side with projecting, elongate, curved, spine-like dorsolateral sclerites.

Material examined. Holotype male: VIETNAM: Ha Giang Province, 1170 m, 22 o 46.07’N, 104 o 49.51’E, 11-16 September 2000, Malaise trap, C. Johnson, K. Long ( AMNH).

Etymology. This species is named for the spinose setae on tergum VIII ( aculeata is Latin for having or bearing spines).

Figures

Figure 1. Chimarra aculeata sp. n., male genitalia. A) Lateral; B) Dorsal; C) Ventral; D) Distal portion of left inferior appendage, dorsal; E) Phallic apparatus, lateral; F) Phallic apparatus, dorsal.