Chimarra dybowskina Navas , 1931

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 dybowskina Navas, 1931

Fig. 8A-E

Chimarrha dybowskina Navás, 1931: 123-124, fig. 61.

Chimarra dybowskina Navás: Fischer 1961: 59; Malicky 2015b: 41 (text), 44 (figure) (distribution: Madagascar); Gibon 2018: 121-122, figs 3A, 5, (distribution: Burkina Faso, Guinea, Ivory Coast, Madagascar, Mali, Togo).

Chimarra divergena Gibbs, 1973: 367-369, figs 5-7. Syn. nov.

Chimarra caboverdensis Nybom, 1960: 1-3, figs A-G. Syn. nov.

Material examined.

Cape Verde ● 1♂; Brava, Fajâ d’ Agua; 100 m a.s.l.; 17 Feb. 2007; E Aistleitner leg.; UMSP . Ghana - Central Reg. ● 1♂; Kakum Forest Reserve; 5°21'N, 1°22'W; 8 Nov. 1994; T Andersen leg.; light trap; ZMBN. - Eastern Reg. ● 1♂ 1♀; Kibi, Subri stream; 6°10'N, 0°33'W; 5 Nov. 1993; J Kjærandsen leg.; light trap; ZMBN. - Volta Reg. ● 1♂; Hohoe, Matvin Hotel; 7°09'43"N, 0°28'31"E; 11 Nov. 1993; J Kjærandsen leg.; at light; ZMBN ● 3♀♀; Wli, Agumatsa waterfall, station # 3; 7°07'29"N, 0°35'31"E; 11-20 Nov. 1993; J Kjærandsen leg.; Malaise trap; ZMBN ● 1♀; same collection data as for preceding except station # 6; ZMBN ● 2♀♀; same collection data as for preceding except station # 7; ZMBN ● 1♀; same collection data as for preceding except station # 8; ZMBN ● 5♂♂ 15♀♀; same collection data as for preceding except station # 3; 17 Nov. 1993; light trap; ZMBN ● 1♀; same collection data as for preceding except station # 6; 11 Mar. 1993; JS Amakye & J Kjærandsen leg.; ZMBN ● 1♀; same collection data as for preceding except 20 Nov. 1993; J Kjærandsen leg.; ZMBN ● 1♂; same collection data as for preceding; UMSP ● 1♂ 3♀♀; same collection data as for preceding except station # 10; 19 Nov. 1993; ZMBN ● 3♂♂ 4♀♀; same collection data as for preceding except station # 12; 16 Nov. 1993; ZMBN ● 1♀; same collection data as for preceding; UMSP .

Diagnosis.

Phallobase with ventral margin greatly produced and strongly bent, apex enlarged and subtruncate, dorsal margin slightly upturned; phallic spines both moderately elongate and narrow; inferior appendage with dorsal projection abruptly narrowed, nearly uniform in width and distinctly bent, apex acute, ventromesal cusps of inferior appendage often both evident in lateral view (character possibly variable or inconsistent).

Chimarra dybowskina is most similar to C. calundoensis , C. falcifera , and C. jacquemarti sp. nov. The species are best distinguished by differences in the shape and inflection of the dorsal lobe of the inferior appendages, and by the shape of the apex and inflection of the apicoventral projection of phallobase, as well as in the relative length of the phallic spines. Like both C. calundoensis and C. Chimarrha jacquemarti , the ventral apex of the phallobase is very strongly bent; the apex of the structure is more truncate than in C. calundoensis , but bent slightly upward, rather than downward, as in C. jacquemarti . The dorsal process of the inferior appendages is generally more uniform in width and more strongly bent in C. dybowskina than in the other species, and the cusps of the mesal surface are more likely to be evident in lateral view. The phallic spines are comparable in length to those of C. jacquemarti , but slightly longer than in either C. calundoensis or C. falcifera .

Our illustration closely matches that presented by Gibon (2018), which was based on the holotype of C. dybowskina Navás from the Democratic Republic of the Congo. We are less convinced that the illustration of C. dybowskina presented by Malicky (2015b) from Nosy Bé, Madagascar is the same species, although admittedly close. The inferior appendage in his illustration has the general shape and form of C. dybowskina , but the ventral projection of the phallobase is not as strongly deflexed and the apex is rounded, rather than truncate.

Chimarra divergena Gibbs, described from Ghana, has enough of the significant features of C. dybowskina to be considered a synonym, especially the strongly deflexed ventral projection of the phallobase, with its apex subtruncate and slightly upturned. There was no available illustration of C. dybowskina when it was published. The primary difference is that the mesal cusps of the inferior appendage are not apparent in lateral view in the illustration of C. divergena . The difference seems too minor to warrant species status. Chimarra caboverdensis is undoubtedly also a synonym, based on the structure of the ventral apex of the phallobase, which, in the illustration of the type, is clearly truncate apically, with the apex slightly upturned. Examination of a specimen collected from Cabo Verde revealed no distinctive differences from C. dybowskina . Pending further evidence of its species status, we prefer to consider C. caboverdensis Nybom to also be a synonym of C. dybowskina Navás.

Redescription.

Adult. Overall color (in alcohol) yellowish brown, head and prothorax not lighter, spurs slightly darker. Head relatively short (postocular parietal sclerite ~ 1/2 diameter of eye). Palps relatively elongate; maxillary palp with 1st segment very short (approximately as long as wide), 2nd segment moderately elongate (~ 4 × 1st), apex with small cluster of stiff setae, 3rd segment slightly longer than 2nd, 4th segment short (~ 1/2 length of 3rd), 5th segment elongate, slightly shorter than 3rd and 4th combined. Forewing length: male, 5.0-6.0 mm; female 5.5-6.5 mm. Fore- and hind wings with forks I, II, III, and V present. Forewing with R1 very slightly sinuous, stem of Rs weakly inflected at past midlength (without distinct node at inflection), basal fork of discoidal cell slightly asymmetric, length of cell ~ 2 × width, fork I slightly subsessile, fork II sessile, r crossvein diagonal, intersecting discoidal cell at past midlength, just before fork I, s and r-m, crossveins linear, m crossvein more proximal, s pigmented (like wing), r-m and m crossveins hyaline, 2A with crossvein (apparently forked apically to 1A and 3A). Hind wing with R1 narrowly parallel to subcosta, fork I and fork II subsessile, fork III relatively distal, anal loop small. Forelegs with tibial spur distinct; male with foretarsi unmodified, claws small and symmetrical.

Male genitalia. Segment VIII with sternum short, ventrally with distinct ventral projection, tergum somewhat wider, expanded dorsally. Segment IX, in lateral view, with anteroventral margin moderately produced, anterior margin with angular inflection at approximately ventral ¼, concavely narrowing dorsally; tergum narrow dorsolaterally, with short anterior apodemes, obsolete mesally between apodemes; posterior margin nearly linear; ventral margin sloping, more or less linear, with elongate, narrow ventral process, apex of process acute as viewed laterally, rounded as viewed ventrally, apicoventral surface of ventral process roughened and file-like; anterior margin of sternum subtruncate as viewed dorsally or ventrally, slightly concave mesally. Lateral lobes of tergum X formed into dorsally curved, sclerotized, spine-like processes, bearing two preapical sensilla; dorsum of tergum X moderately elongate, membranous; tergum ventrally with strongly projecting, paired, sclerotized, periphallic processes, subtending phallic apparatus. Preanal appendages short and knob-like, constricted basally, fused laterally to periphallic processes. Inferior appendage with pronounced basal inflection, apex dorsally inflected and strongly narrowed, distinctly posteriorly curved, apex acute; as viewed ventrally, with distinct sclerotized projections near base and before midlength, generally evident in lateral view; mesal surface without projections or ridges. Phallic apparatus with phallobase tubular, with usual basodorsal expansion, apicoventral margin sclerotized, strongly deflexed and projecting, apex enlarged, subtruncate, with dorsal margin slightly upturned; endotheca with two relatively elongate, asymmetrically positioned spines, membrane textured with small spines, phallotremal sclerite complex composed of short rod and ring structure.

Distribution.

Burkina Faso, Cape Verde, Democratic Republic of the Congo, Ghana, Guinea, Ivory Coast, Madagascar, Mali, Togo.

Figures

Figure 8. Chimarra dybowskina Navas, ♂ genitalia A lateral B dorsal, segments IX and X C inferior appendage, caudal D tergum X and periphallic process, right caudal E phallus, lateral.