Chimarra serrella, Blahnik & Andersen, 2022

Blahnik, Roger & Andersen, Trond, 2022, New species of the genus Chimarra Stephens from Africa (Trichoptera, Philopotamidae) and characterization of the African groups and subgroups of the genus, ZooKeys 1111, pp. 43-198 : 43

Chimarra serrella sp. nov.

Fig. 46A-F

Type material.

Holotype. Ghana - Western Reg. ● ♂ (in alcohol); Ankasa Game Production Reserve; 5°15'N, 2°37'W; 31 Mar. 1993; JS Amakye & J Kjærandsen leg.; light trap; UMSP 000550043. Paratypes. Ghana - Western Reg. ● 8♂♂; same data as for holotype except 6-12 Dec. 1993; T Andersen & J Kjærandsen leg.; Malaise trap; ZMBN.

Additional material.

Ghana - Western Reg. ● 9♀♀; Ankasa Game Production Reserve; 5°15'N, 2°37'W; 6-12 Dec. 1993; T Andersen & J Kjærandsen leg.; Malaise trap; ZMBN ● 1♀; same collection data as for preceding; UMSP .

Diagnosis.

Chimarra serrella is very similar to C. uncinata sp. nov. and the two undoubtedly constitute a pair of closely related sister species. The species resemble each other in the distinctive shape of the apex of the phallobase, and in the general shape of their inferior appendages, which are short, linear, and acute apically, as viewed laterally, but have the apex obliquely subtruncate, as viewed ventrally, with the ventromesal margin distinctly serrate. Neither species has cusps or projections on the mesal surface of the inferior appendages. The most distinctive difference is in the shape of tergum X, which has its apex upturned and hooked in C. uncinata , and very narrow and strongly downturned in C. serrella . The apex of the inferior appendage, in lateral view, is also more acute in C. serrella than in C. uncinata .

Description.

Adult. Overall color (in alcohol) light brown, underside and appendages yellowish brown, setal warts of head not distinctly contrasting. Head short (postocular parietal sclerite short). Palps elongate; maxillary palp with 1st segment very short (approximately as long as wide), 2nd segment moderate (~ 3 × 1st), apex with cluster of ~ 6-8 stiff setae, 3rd segment elongate, 4th segment short (shorter than 2nd), 5th segment elongate and narrow (subequal to 3rd and 4th combined). Forewing length: male, 3.5-4.0 mm; female, 3.7-4.4 mm. Fore- and hind wings with forks I, II, III, and V present. Forewing with R1 straight, stem of Rs straight, or nearly so, basal fork of discoidal cell slightly enlarged, evenly forked, length of cell ~ 2 × width, fork I subsessile, fork II sessile, r crossvein diagonal, intersecting discoidal cell before apical fork, s, r-m, and m crossveins linear and hyaline, both 2A and 3A looped to 1A (2A without apical fork). Hind wing with R1 obsolete (or fused to subcosta), forks I and II subsessile, fork III distal and relatively narrow, anal loop small. Forelegs with apical tibial spur very short; male with modified tarsal claws, apical three segments of tarsi short and flattened, claws asymmetrical, outer one elongate and twisted.

Male genitalia. Segment VIII short, tergum longer than sternum, sternum without posteroventral process. Segment IX, in lateral view, very short, anteroventral margin only slightly projecting, dorsal margin without apodemes, but with pair of short, rounded, multi-sensillate projections from posterior margin, ventral process very short, subtriangular, not or scarcely projecting, inferior appendages inserted slightly above ventral margin of segment; as viewed dorsally, with tergum very narrow, but continuous, sternum short, subtruncate. Tergum X with mesal lobe very short and membranous, lateral lobes short and distinctly sclerotized, produced apically into tapering, ventrally recurved, spine-like projections; sensilla of lobes very small, reduced in number, possibly only two, on basal part of tergum. Preanal appendages short, oblong, somewhat ventrally projecting, inserted membranously (not fused to segments IX or X). Inferior appendage with very weak basal inflection; as viewed laterally, more or less ovate, acutely angulate apically, with short lateral setae, setae slightly longer and spaced on dorsal margin; as viewed ventrally, with apex obliquely truncate, with longitudinal ridge near mesal margin, mesal margin distinctly serrate. Phallic apparatus with phallobase very short and strongly sclerotized, with usual basodorsal expansion, securely anchored within segment by semi-sclerotized periphallic membrane (attached to lateral margin of segment IX), apicoventral margin of phallobase very distinctly sclerotized and produced, down-turned, apex produced into short apical spine-like processes, ventral one weakly divided, dorsolateral margin of apex with additional short spine-like projection on each side; endotheca short, membranous, with small, lightly sclerotized apical spine, apex bluntly rounded, as viewed ventrally; phallotremal sclerite complex composed of short rod and ring structure, with indistinct apicolateral sclerite.

Etymology.

Chimarra serrella , used as a noun in apposition, from the Latin diminutive for serra, a saw, in reference to the very serrate ventromesal margin of the inferior appendages in this species.

Figures

Figure 46. Chimarra serrella sp. nov., ♂ genitalia A lateral B dorsal, segments IX and X C inferior appendage, ventral D inferior appendage, dorsal E phallus, lateral, with dorsal detail of phallotremal sclerite complex F phallus, ventral.