Cheumatopsyche rantsoa Oláh & Johanson, 2008

Oláh, J. & Johanson, K. A., 2008, Generic review of Hydropsychinae, with description of Schmidopsyche, new genus, 3 new genus clusters, 8 new species groups, 4 new species clades, 12 new species clusters and 62 new species from the Oriental and Afrotropical regions (Trichoptera: Hydropsychidae), Zootaxa 1802, pp. 1-248 : 223-225

Cheumatopsyche rantsoa Oláh & Johanson , new species

Fig. 375–379

This species is similar to C. masiposa , new species from which it is distinguished by the more drawn bowshaped anterior margins of segment IX; segment IX being more strongly shifted posterad, especially on dorsum; the more deeply excised anterodorsally in lateral view; the perfectly rounded apex of segment X; the basal half of the coxopodites being thicker; and the harpagones with narrower basis. The most pronounced distinguishing character is the darker forewing pattern, compared to the uniformly coloured forewings of C. masiposa .

Male. Body brown, forewing membrane pale brown with dark pubescence. Maxilary palp formula I-(III, IV)-II-V, segment V as long as sum of segments I–IV. Head dorsum brown with brown setal warts. Swollen setal wart absent on proepisternum. Pretarsal claws asymmetrical, laterally flanked by setal bundle. Protibiae with 2 apical spurs, posteroapical spur small.

Wings. Forewing ( Fig. 375) crossveins m-cu and cu tangential. Cu2 and A1 running close before meeting at wing margin. Fork 1 present. Wing membrane pale brown with pronounced pattern; apical area dark, dark patches on crossveins s, s-m, m, and along tangential area of crossveins m-cu and cu. Forewing length 9.0 mm.

Male genitalia (376–379). Abdominal segment IX fused annularly, tergum shorter than sternum ( Fig. 376). Anterior margins of segment IX almost regular bow-shaped with long straight middle section ( Fig. 376); dorsal section strongly drawn in lateral aspect. Apical lobe on posterolateral margins short, nearly triangular ( Fig. 376); located above articulation cavity of gonocoxites. Antecosta well developed, widening before margin, with well visible external groove of antecostal suture; vestigial acrotergite visible. Spine row on posterior margins of segment IX complete ( Fig. 376); spines heterogenous; irregularly bending on laterocaudal lobes of dorsum; spines on border between segments IX and X about half as long as spines on posterior margins; spines on apical lobes about one-third as long as spines on posterior margins; stiff, straight. Intersegmental step between segments IX and X filled and occupied by pair of setose protuberances; forming setose, laterocaudal lobes. Body of segment X, long, nearly triangular, with dorsad curving, blunt, apex in lateral aspect ( Fig. 376); simple, rounded, long lobe-shaped in dorsal aspect ( Fig. 377); ventrum not bellied. Apicoventral setal lobes slightly curving dorsad ( Fig. 376), mesally fused with segment X, dominating distal part of segment X; delineated by setae; rounded; dorsum flat in dorsal view ( Fig. 377). Smooth, mesal lobes reduced; dorsal interlobular gap small, narrow, shallowly half-circular ( Fig. 377). Apicoventral lobes separated by dorsal, interlobular gap; lobes forming flaps with straight-cut dorsum in dorsal view ( Fig. 377); shape highly dependent on observation angle. Unique setose structures present at basis of dorsolateral areas of segment X forming pair of well-developed protuberances representing laterocaudal lobes derived from dorsal apex of spine row on posterior margin of segment IX. Transverse sutures not visible. Longitudinal sutures running along ventral margin of segment ( Fig. 376); forming continuation of apicoventral setose lobes. Setose areas (superior or preanal appendages) forming pair of elevated, circular, flap-like warts located centrally on segment X. Coxopodites exceeding apex of segment X, basally slender; distally broadening and slightly bending downwards from mid-length. Harpagones with short, broad triangular basis ( Fig. 376); continuing into long, dorsad curving, thin, digitate process; cickle-shaped in ventral view ( Fig. 378). Phallothecal phallobase enlarged ( Fig. 379), straight, horizontal shaft parallel-sided, slightly constricting at mid-length. Endophallus long, not filling entire phallotheca. Chitinezed endothecal process circular, almost as wide as shaft. Phallotremmal sclerites broad, rounded and sinuate in lateral aspect.

Holotype male: MADAGASCAR: Fianarantsoa Province, 7 km W Ranomafana , 900 m, black light, mountain rainforest near river and stream, 18.x.1990 [W.E. Steiner, C. Kremen & P. Daniels] - 2 males ( NMNH, pinned).

Paratypes: same data as holotype — 1 male ( NMNH) , 1male ( OPC) ; same data as holotype, except 8– 13.iii.1990 [W.E. Steiner] - 1 male ( NMNH) ; ditto, except 20–24.iii.1990 - 1 male ( NMNH) ; ditto, except - 1 male ( NMNH) ; ditto, except - 1 male ( NMNH) .

Distribution. Madagascar.

Etymology. rantsoa , name derived from the type locality, Fianarantsoa Province.