Chirosiomima obscurinervis ( Emden, 1941 )

Michelsen, Verner, 2014, Taxonomic assessment of Chirosiomima Hennig (Diptera: Anthomyiidae), with proposal of a new genus for Hylemyia curtigena Ringdahl, Zootaxa 3790 (1), pp. 86-102 : 91-94

Chirosiomima obscurinervis ( Emden, 1941) , sp. rev.

( Figs. 3 , 10, 11 , 14 )

Pegomyia obscurinervis Emden, 1941: 262 .

“ Chirosiomima gestroi (Séguy) ”; Hennig 1966: 30 (in part: Iran), text figs. 27–31, table figs. 11, 39, 70; Hennig 1976a: 928 (in part: Iran); Hennig 1976b: lix, text figs. A129, A130; Pont & Ackland 1980: 716. Misidentifications.

Identity of Pegomyia obscurinervis Emden. Because of wartime Emden (1941) described Pegomyia obscurinervis in a few words only in a key based on an unspecified number of [male] specimens from Ghana (“ Gold Coast ”) and Yemen (“ Aden Protectorate ”). He did not even mention that the head of the male is broadfronted, fully feminized, but stated that the assignment of this tiny anthomyiid in Pegomyia was quite preliminary, as it differed substantially from known members of that genus, e.g. by having an apical pv seta on hind tibia. Pont & Ackland (1980) saw the type material in the London Museum and transferred Emden’s species to the genus Chirosiomima Hennig. They further treated Emden’s species as a new junior synonym of C. gestroi ( Séguy, 1930) , because they found that the male terminalia, notably the presence of some huge and curiously modified setae on sternite V, agreed with Hennig’s (1966) redescription of C. gestroi . However, it is now evident that the “new” material from Iran on which Hennig based his redescription of C. gestroi belongs to a different, but closely related species. Present examination of the Iranian material in the Stuttgart Museum consisting of 1♂ and 11♀ revealed that this belongs to C. obscurinervis ( Emden, 1941) . Accordingly, that species is presently resurrected from synonymy.

Material examined. GHANA (“ Gold Coast ”): Accra [5°32'N, 0°12'W], lectotype ♂ of Pegomyia obscurinervis Emden, 1941 by present designation, “in house” iv.1921 (J.W. Scott Macfie) [ BMNH]. YEMEN (“ Aden Protectorate ”): Al Waht, ca. 6mls S of Lahij (“Lahej”) [12°58′N 44°53′E], 70m, “taken at light in government guest-house”, paralectotype ♂ (mid and hind legs and abdomen missing) 11.i.1940 (P.W.R. Petrie) [ BMNH]. IRAN: Sistan & Baluchestan Province: Iranshahr [27°12′N 60°41′E], 800m, 1♀ 1–10.iv.1954, 2♀ 11–21.iv.1954 (W. Richter & F. Schäuffele) [ SMNS]; dunes NW of Espakeh (“Rig Ispakeh”) [26°50′N 60°10′E], c. 760m, 1♂ 7♀ 2.iv.1954 (W. Richter & F. Schäuffele) [ SMNS, ZMUC]. Kerman Province: Anbarabad SW of Jiroft (“Anbar-Abad, Djiroft”) [28°28′N 57°50′E], c. 600m, 1♀ 21–30.iv.1956 (W. Richter) [ SMNS].

Description. Very similar to C. gestroi (Séguy) , but different as follows: Parafrontalia on upper part, at level of antennal bases, with a conspicuous circular, blackish mark ( Fig. 3 ). Ground colour of thorax more variable, ranging from wholly ochre yellow (as seen in the type specimens from Ghana and Yemen) to wholly dark, often with only postpronotal lobes and tip of scutellum ochre yellow. Ground colour of abdomen also more variable, ranging from wholly dark including the terminalia to wholly ochre yellow. Femora and tibiae ochre yellow or more or less darkened, especially the femora; tarsi or at least distal tarsomeres brownish infuscate, darker than tibiae. Wing with cross-veins r–m and dm–cu darkened and narrowly clouded (often very faded in old specimens!). Male: Sternite V ( Fig. 10 ) with 4–5 enlarged and flattened, inwardly directed setae on posterior lobes. Surstyli ( Fig. 11 ) shorter, narrower distally and with apical incision poorly developed. Female: Sternite VI ( Fig. 14 ) on posterior part convex and forming a small submarginal hump.

Distribution. Known by single male individuals from Ghana and Yemen ( Emden 1941). Presently also recorded from Iran.

Biology. Found in a dune area in Iran. Also taken “in house” in Ghana and “at light in government guesthouse” in Yemen.

Figures

FIGURES 1 – 3. Chirosiomima spp. 1. C. gestroi, male from Tunisia, habitus. 2. Same, labella. 3. C. obscurinervis, female from Iran, habitus. Scale bars: 1 mm (1, 3); 0.1 mm (2).

FIGURES 10 – 12. Chirosiomima spp. 10. C. obscurinervis, male from Iran, sternites IV and V. 11. C. obscurinervis, lectotype male from Ghana, hypopygium, posterolateral view. 12. C. gestroi, female from Tunisia, oviscapt, flat mount (s = sternite; sp = spiracle; t = tergite). Scale bars: 0.25 mm.

FIGURES 13, 14. Chirosiomima spp., oviscapt, lateral view. 13. C. gestroi, female from Tunisia (s = sternite; sp = spiracle; t = tergite). 14. C. obscurinervis, female from Iran (arrow: hump on sternite VI). Scale bar: 0.25.