Chimarra wliensis, 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 wliensis sp. nov.

Fig. 27A-E

Type material.

Holotype. Ghana - Volta Reg. ● ♂ (in alcohol); Wli, Agumatsa waterfall, station # 2A; 7°07'29"N, 0°35'31"E; 8-11 Mar. 1993; JS Amakye & J Kjærandsen leg.; Malaise trap; UMSP 000550021. Paratypes. Ghana- Volta Reg. ● 1♂; same data as for holotype except station # 1A; 5-14 Mar. 1993; ZMBN ● 1♂; same data as for holotype except station # 3; 11-20 Nov. 1993; J Kjærandsen leg.; ZMBN. - Western Reg. ● 1♂; Ankasa Game Production Reserve; 5°15'N, 2°37'W; 12 Dec. 1993, T Andersen & J Kjærandsen leg.; sweep net; ZMBN.

Additional material.

Ghana - Volta Reg. ● 5♀♀; Wli, Agumatsa waterfall, station # 2A; 7°07'29"N, 0°35'31"E; 5-14 Mar. 1993; JS Amakye & J Kjærandsen leg.; Malaise trap; ZMBN ● 1♀; same collection data as for preceding except 8-11 Mar. 1993; UMSP ● 1♀; same collection data as for preceding except station # 2B; ZMBN ● 1♀; same collection data as for preceding except station # 3; 17 Nov. 1993; J Kjærandsen leg.; light trap; ZMBN .

Diagnosis.

Chimarra wliensis is a very distinctive species, easily recognized by the curved, spine-like, and scabrous lateral lobes of tergum X and the shape of its inferior appendages, in addition to it venational attributes.

Superficial similarities would suggest a relationship to species in the Chimarrha georgensis Group, because of the scabrous dorsolateral processes on segment IX, as in the Chimarrha evoluta subgroup, and the sclerotized and divided lateral lobes of tergum X, as in the Chimarrha georgensis subgroup, as well as its rather simple and short phallobase, with a produced ventral apex. However, venational characters place this species within the Chimarrha marginata Group, since the anal veins have a distinct crossvein (2A apparently forked apically), the Rs vein of the forewing is distinctly curved, with the s crossvein pigmented (not hyaline), and the m crossvein is distinctly proximal to the s and r-m crossveins. In overall morphology the species is thus distinctive. It is conceivably related to C. berghei (Marlier), whose overall description makes it difficult to place; similarities to C. wliensis include, particularly, the arching dorsolateral lobes of tergum X; however, C. berghei differs significantly in the shape of its inferior appendages and it is possible that it is not very closely related.

Description.

Adult. Overall color (in alcohol) medium brown, head and thorax not paler than body. Head elongate (postocular parietal sclerite nearly as long as diameter of eye). Palps elongate; maxillary palp with 1st segment very short (approximately as long as wide), 2nd segment elongate (subequal to 3rd), apex with numerous elongate, stiff setae, 3rd segment elongate, 4th segment short (~ 1/3 length of 3rd), 5th segment elongate and narrow (subequal to 3rd). Forewing length: male, 5.7-6.5 mm; female, 6.5-7.5mm. Fore- and hind wings with forks I, II, III, and V present. Forewing with R1 somewhat curved, stem of Rs curved, bowed outward, without sclerotized node in cell below, basal fork of discoidal cell slightly enlarged, nearly evenly forked, length of cell ~ 2 × width, forks I and II sessile, r crossvein diagonal, intersecting discoidal cell before fork, s crossvein pigmented, r-m and m hyaline, s and r-m crossveins continuous, m crossvein distinctly proximal; 2A with crossvein (apparently forked apically to 1A and 3A). Hind wing with R1 obsolete (or fused to subcosta), forks I and II subsessile. Forelegs with apical tibial spur very short; male with apical segments of foreleg small and thread-like, not enlarged, tarsal claws symmetrical.

Male genitalia. Segment VIII short, tergum longer than sternum. Segment IX short, anterior margin expanded and rounded in ventral half, segment very short dorsally, anterodorsal margin with distinct rounded apodemes, posterodorsal margin with elongate, scabrous, posteriorly-curved, spine-like lateral processes, ventral process very short, subtriangular, more or less ventrally oriented, inferior appendages inserted distinctly above ventral margin of segment; as viewed dorsally, with tergum very narrow, but continuous, sternum short, broad, weakly concave mesally, scabrous dorsolateral processes of segment mesally curved, meeting mesally. Tergum X with mesal lobe membranous and with textured region at at base, lateral lobes (or periphalic processes?) strongly sclerotized and ventrally curved, divided apically into acute lobes, sensilla of lobes absent (or not evident). Preanal appendages short, knob-like, inserted membranously (not fused to segments IX or X). Inferior appendage with moderate basal inflection; as viewed laterally, more or less narrow, moderately elongate, apex acute; as viewed ventrally, with prominent, acute apicomesal projection (thus, ventral and apical projections subequal and separated by crescentic margin); mesal margin with short cusp, continuous with apical projection. Phallic apparatus with phallobase short and strongly sclerotized, with usual basodorsal expansion, apicoventral margin of phallobase projecting, sclerotized, acute, distinctly ventrally curved; endotheca apparently short, membranous, with single short spine; phallotremal sclerite complex composed of short rod and ring structure.

Etymology.

Chimarra wliensis , used as an adjective, meaning "from Wli", for the site where the holotype of this species was collected.

Figures

Figure 27. Chimarra wliensis sp. nov., ♂ genitalia A lateral B dorsal, segments IX and X C inferior appendage, ventral D inferior appendage, dorsal E phallus, lateral.