Chimarra undulata, 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 : 12-14

Chimarra undulata sp. n.

( Figure 5 )

Diagnosis. We are unsure of the closest affinity of this species. Among species in the tsudai Group, it is distinctive because of the shape of the inferior appendages, which are very broad basally, as viewed laterally, tapering linearly to an acute apex. The relatively elongate, broad, undulate shape of the lateral lobes of tergum X constitutes a useful additional diagnostic character.

Description. Forewing length (male) 5.0 mm, (female) 5.5 mm. Color (in alcohol) pale yellowishbrown, appendages and setal warts yellowish-white. Head moderately elongate (postocular parietal sclerite somewhat extended behind eye). Mesoscutellar setal wart pear-shaped, without apparent anterior suture. Maxillary palps with 1 st segment very short, 2 nd segment moderate in length (shorter than 3 rd, longer than 4 th), 3 rd segment elongate, subequal to segment 5, 4 th segment short. Tarsi of males distinctly modified, tarsal claws enlarged and sinuous, asymmetric in length and curvature. Forewing with Rs distinctly deflected (curved toward anal margin) and weakly, sinuously inflected before base of discal cell; veins at base of discal cell slightly 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 relatively short, partially subtending ventral margin of segment IX, ventrally with distinct, short, subacute, posteroventrally projecting process at midlength; tergum widened dorsally, dorsal margin protruding, length about 1.5 times that of sternum, without distinct modifications. Segment IX unsclerotized dorsally, with distinct, small dorsolateral apodemes on anterior margin; in lateral view, with anterior margin extending nearly linearly from apodemes, curved in ventral half to form projecting ventral margin, anteroventral margin (as viewed dorsally or ventrally) with lateral margins tapering, subtruncate mesally; segment very short dorsally at level of preanal appendages (anterior and posterior margins very narrowly separated), posterior margin greatly lengthened below preanal appendages to dorsal margin of inferior appendages (about midheight of segment), then abruptly, angularly bent, extending linearly to ventral margin of segment; ventral process very short and ventrally projecting, broad basally, rounded apically. Tergum X, as viewed laterally, with lateral lobes relatively elongate and broad (greater in total length than inferior appendages), each with weakly rounded projection on basodorsal and ventral margins, apex rounded, sensilla mostly restricted to dorsal, ventral, and apical margins; mesal lobes of tergum X digitate, rather strongly reclinate, posteriorly directed, each with about 4 small sensilla near apex. Preanal appendages moderately large, rounded, laterally flattened, fused basally to posterior margin of segment IX. Inferior appendages moderately elongate; as viewed laterally, trianguloid, base very broad, dorsal and ventral margins linear, tapering to sclerotized apex, apex with apparent mesal curvature even in lateral view; appendages, as viewed ventrally, with lateral margins curved (more strongly near base and at apex), mesal margins nearly linear, apices of appendages incurved and appearing acute; apices, as viewed caudally, narrowly subtruncate (very weakly emarginate). Phallotheca relatively short, tubular, slightly widened from base to apex, basal expansion moderate. Endotheca (apparently) short and membranous, without spines. Phallotremal sclerite complex very enlarged and elongate, about two-thirds length of phallotheca; ring structure not apparent as such, but with elongate, paired, dorsolateral sclerites projecting from general region of “ring”, each forked preapically, apices of both branches acute; ventral “rod” elongate, sclerotized, evident.

Material examined. Holotype male: VIETNAM: Quang Nam Province, Ngoc Linh , 950 m, 15 o 10’N, 108 o 5’E, 16 April 1999, Malaise trap, K. Long, C. Johnson ( AMNH).

Etymology. This species is named for the undulate dorsum of the lateral lobes of tergum X (unda is Latin for wave).

Figures

Figure 5. Chimarra undulata sp. n., male genitalia. A) Lateral; B) Dorsal; C) Ventral; D) Phallic apparatus, lateral; E) Phallic apparatus, dorsal.