Chimarra carinata, 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 : 21-23

Chimarra carinata sp. n.

( Figure 9 )

Diagnosis. This is a distinctive species, best diagnosed by the very short lateral lobes of tergum X, each of which has a digitate ventral projection, and also by the structure of the inferior appendages, which are ovate and each have two mesal cusps, best seen in caudal view. The species is interesting in having some plesiomorphic features that characterize the georgensis “Group”, including a forewing with unmodified Rs vein, hyaline and linearly aligned cross-veins, and anal veins without an apical fork. It also possesses the apomorphic fusion of the Sc and R 1 in the hind wing that characterizes species in the georgensis “Group”, but lacks the highly modified and shortened phallotheca found in the type species for the group. As discussed above, fusion of the Sc and R 1 in the hind wing seems to have occurred in a number of lineages (as for instance, in the minuta Group discussed above and in the subgenus Otarrha ). The character occurs especially among smaller species.

Description. Forewing length (male) 4.0 mm. Color (in alcohol) light yellowish-brown. Head relatively short (postocular parietal sclerite not elongate). Mesoscutellar setal wart pear-shaped, with very weak anterior suture. Maxillary palps with 1 st segment very short (about as long as wide), 2 nd segment short (length about 2 times width), 4 th segment subequal to 2 nd, 3 rd segment very long (more than 3 times length of segment 2), 5 th segment subequal to segment 3. Tarsi of male very narrow, tarsal claws very small, symmetrically curved (unmodified). Forewing with Rs straight, not noticeably modified; 1 st fork slightly proximal to s cross-vein; s, r-m, and m cross-veins hyaline (unpigmented) and linearly aligned; anal veins without apical fork (2A and 3A both apparently looped to 1A). Hind wing with Sc and R

1

fused.

Male genitalia: Segment VIII with sternum short, subtending ventral margin of segment IX; tergum somewhat widening dorsally, without distinct modifications. Segment IX with dorsal margin sclerotized, anteromesal margin concave as viewed dorsally; segment relatively short dorsally (anterior and posterior margins narrowly separated), longer ventrally (more than 3 times dorsal length); as viewed laterally, without distinct dorsolateral apodemes on anterior margin, anterolateral margin distinctly, sinuously produced ventrally, from about level of preanal appendages (ventromesal margin emarginate as viewed dorsally or ventrally); posterior margin somewhat angularly widened below preanal appendages to ventral margin of inferior appendages, narrowing ventrally to ventral process; ventral process from about middle of segment, very small, subtriangular, ventrally projecting. Tergum X with mesal lobe short and slightly elevated, lightly sclerotized, lobe with mesal invagination, extending about half length of lobe; mesal lobes very short, scarcely longer than dorsal lobe, relatively simple in overall structure, each lobe with narrow, digitate projection from posteroventral margin, projections converging mesally below phallic apparatus; each lobe with prominent sensillum at base of digitate projection and also with 2 small lateral sensilla. Preanal appendages prominent, rounded as viewed laterally, somewhat laterally flattened, emerging intersegmentally between posterior margin of segment IX and base of tergum X. Inferior appendages simple in structure, ovate as viewed laterally or ventrally, with fine setae, those near apical margin very elongate; each appendage with sclerotized tooth-like projection on dorsal margin, acute as viewed laterally, broadly cusped as viewed caudally, and also 2 nd small, acute tooth on mesal surface, near ventral margin. Phallotheca moderately elongate, tubular, with usual basal expansion; ventrally with longitudinal keel, extended in basal part to form rounded projection, as viewed laterally. Endotheca membranous (untextured), unexpanded in specimen examined, but with apparent cluster of short curved spines. Phallotremal sclerite complex not evident, possibly small or weakly sclerotized.

Material examined. Holotype male: VIETNAM: Quang Nam Province, Ngoc Linh , 950 m, 15 o 11.2’N, 108 o 2.3’E, 23 March 1999, Malaise trap, D. Grimaldi, L. Herman, C. Johnson, K. Long, E. Sterling ( AMNH).

Etymology. This species is named for the longitudinal ventral keel of the phallotheca ( carinata is Latin for keeled).

Figures

Figure 9. Chimarra carinata sp. n., male genitalia. A) Lateral; B) Dorsal; C) Ventral; D) Left inferior appendage, dorsal; E) Phallic apparatus, lateral; F) Phallic apparatus, dorsal; G) Phallic apparatus, ventral.