Chimarra usambara, 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 usambara sp. nov.

Fig. 26A-E

Type material.

Holotype. Tanzania - Tanga Reg. ● ♂ (in alcohol); East Usambara Mts, Sigi River, Amani; 21 Feb. 1959; 2.500 ft; MT Gillies leg.; INHS Trichoptera 50335. Paratypes. Tanzania - Tanga Reg. ● 1♀; same data as for holotype; INHS $ 1♂; Amani; 16 Nov. 1959; MT Gillies leg.; INHS.

Diagnosis.

Chimarra usambara is very similar to C. mazumbai sp. nov. and, like that species, has a short tergum X with a pair of upturned, spine-like processes. It is easily distinguished from C. mazumbai in that the spine-like processes of the tergum are more closely adpressed, and by the shape of its inferior appendage, which has a more distinctly defined and upturned, thumb-like dorsal process.

Description.

Adult. Overall color (in alcohol) dark brown. Head moderately elongate (postocular parietal sclerite ~ 1/2 diameter of eye). Palps elongate, maxillary palp with 1st segment short (length subequal to width), 2nd segment very elongate, with approximately a dozen elongate apical setae, 3rd segment moderately elongate (shorter than 2nd), 4th segment short, 5th segment elongate (subequal to 2nd). Forewing length: male, 4.7 mm; female, 5.0 mm. Fore- and hind wings with forks I, II, III, and V present. Forewing with R1 not, or only very weakly, sinuous, stem of Rs with relatively weak inflection in apical half, with node at inflection, extending into cell below, basal fork of discoidal cell enlarged, fork very asymmetric, discoidal cell with length ~ 2 × its width, forks I and II slightly subsessile, r crossvein diagonal, intersecting discoidal cell at past midlength, just before fork I, r-m crossvein continuous with s, m crossvein proximal to s and r-m crossveins, approximately midway between basal fork of M and r-m crossvein, s pigmented (like wing), r-m and m crossveins hyaline, very indistinct, 2A with crossvein (apparently forked apically to 1A and 3A). Hind wing with R1 narrowly parallel to subcosta, forks I and II subsessile. Foreleg with apical tibial spur apparently absent; male with foretarsi unmodified, claws small and symmetrical.

Male genitalia. Segment VIII short ventrally, tergum somewhat wider dorsally. Segment IX, in lateral view, relatively short, anterior margin relatively weakly, sinuously produced in ventral half, dorsolaterally with distinct rounded apodeme; tergum, in dorsal view, obsolete between apodemes; posterior margin short dorsally, weakly produced below preanal appendages, nearly linear to ventral margin, ventral margin with short, small, posteriorly projecting, ventral process. Segment IX, in dorsal or ventral views, with anteroventral margin subtruncate. Lateral lobes of tergum X very short and rounded, with pair of closely apposed and very narrow, digitate, dorsally projecting, recurved, apically acute processes from apicoventral margin, projections slightly scabrous, sensilla not apparent; mesal lobe of tergum X membranous, short, hardly projecting beyond base of lateral lobes. Preanal appendages short, rounded, knob-like, distinctly constricted basally. Inferior appendage, in lateral view, short, densely setose, strongly rounded basally, dorsally with thumb-like, dorsally flexed projection; in ventral view, with short, acute, mesally curved, apicoventral projection, only indistinctly visible in lateral view; in caudal view, with narrow spine-like projection visible on mesal surface. Phallic apparatus with phallobase very short and tubular, with usual basodorsal expansion, apicoventral margin forming distinct, ventrally curved, projection; endotheca membranous and simple in structure, without spines; phallotremal sclerite complex composed of relatively short, simple, rod and ring structure, with associated sclerites absent or not apparent.

Etymology.

Chimarra usambara , name used as an adjective, after the East Usambara Mountains of Tanzania, in which this species was collected.

Figures

Figure 26. Chimarra usambara sp. nov., ♂ genitalia A lateral B dorsal, segments IX and X C inferior appendage, ventral D inferior appendage, caudal E phallus, lateral.