Aphaniosoma aegyptium, Ebejer, 2023

Ebejer, Martin J., 2023, The genus Aphaniosoma Becker, 1903 (Diptera: Chyromyidae) in the Eastern Mediterranean and Middle East, with descriptions of new species, European Journal of Taxonomy 872, pp. 1-161 : 19-23

Aphaniosoma aegyptium sp. nov.

urn:lsid:zoobank.org:act:E71BF3B7-32DE-4FDD-8E6B-3DA7D74F38DD

Figs 4–5

Diagnosis

A yellow species with black longitudinal scutal vittae ( Fig. 4B ) and strong prealar and dorsocentral setae, but no presutural intra-alar. Male with a long narrow surstylus curved postero-medially at apex and easily visible without dissection ( Fig. 5B ); male also with a short narrow projection on hind trochanter ( Fig. 5A ). Similar species: A. hackmani Lyneborg, 1973 and A. harteni Ebejer, 1996 have a similar hind trochanter in the male, but neither of these has a strong presutural intra-alar seta and they have differently shaped structures in the hypopygium, although the surstylus looks very similar. A. verecundum Ebejer, 1998 is similar to the new species in that it shares the same chaetotaxy and the appearance of the male 5 th tergite, which is shorter dorsally compared to laterally, but there is no projection on the male hind trochanter. The hypopygial differences between the three species are subtle with regard to the surstylus (thickening at base and apical curvature), shape of tergite 6 and epandrium, but more clearly apparent in the shapes of sternites 5 and 6 (compare A. aegyptium Fig. 5B–C with A. hackmani Fig. 34B–C and Ebejer 2016: fig. 15a–b for A. harteni ).

Etymology

The species epithet is the Latin ‘ aegyptium’, for ‘Egyptian’, and refers to the type locality.

Material examined

Holotype

EGYPT • ♂; Kafr Elsheikh; 30.48° N, 31.14° E; 28 Mar. 1996; M. Barták leg.; garden vegetation; CUSLP.

Paratypes

EGYPT • 3 ♀♀; same collection data as for holotype; CUSLP.

Description

MEASUREMENTS. Body length: male 1.5 mm, female 1.6 mm. Wing length: male 1.7 mm, female 1.8 mm.

Male, holotype

HEAD. Yellow except for black ringed ocelli ( Fig. 4B ); almost spherical; frons narrowed anteriorly: at level of antennae about 0.7 × as wide as at level of anterior ocellus; gena: narrow in front, deeper behind; viewed in profile, below middle of eye, about equal to height of eye and with numerous yellow setulae; occiput in profile narrowly visible behind eye; long postocular setulae in one row; 3 long white vibrissal setulae; face short, poorly sclerotized and depressed; median carina poorly developed; antenna yellow, pedicel paler than basal flagellomere and with distinct short seta dorsally; basal flagellomere with fine but distinct pubescence along anterior margin, as long as diameter of first segment of arista; first segment of arista yellow, second brown on basal ¼, black on apical ¾, with fine pubescence; chaetotaxy: 2 strong fronto-orbitals, paraverticals short and crossed; 1 inner and 1 outer vertical, both strong; ocellars about as long as anterior fronto-orbital; about 16 short brown setulae across middle of frons all more or less of same size.

THORAX ( Fig. 4B ). Yellow; scutum with black longitudinal vittae and thin yellow microtomentum; vittae run between rows of setae; scutellum yellow with lateral dark brown spot along margin at base; mediotergite dark brown; pleura yellow with darker yellow on middle of katepisternum and meron; chaetotaxy: 1 postpronotal, 1 incurved intra-postpronotal, 1 long presutural, 2 notopleurals, 0+3 intra-alars, 1 postalar, 1+3 dorsocentrals, 1+6 acrostichals with prescutellar setae, 4 scutellars, 1 anepisternal with 2 shorter setae below it, 1 katepisternal at upper posterior corner.

WING. Veins all pale yellowish brown; distance on costa between R 2+3 and R 4+5 about 0.5 × that between R 4+5 and M 1; distance between crossveins about 1.3 × as long as posterior crossvein, which is oblique and is about 0.5 × as long as apical section of M 4. Haltere pale yellow.

LEGS. Fore femur with long setae on postero-dorsal aspect; numerous pale brown setulae scattered on all legs; apico-ventral seta on mid tibia present; claws black in apical half and pulvilli normal; 5 th tarsomere of all legs black and 4 th brown; hind trochanter modified with a posteromedial process that is narrow, short, blunt and bearing a few minute setulae at apex ( Fig. 5A ).

ABDOMEN. Tergites brown dorsally, becoming paler laterally and then darkening again along ventral margin; tergite 5 medially on dorsum narrower than on lateral margin; tergite 6 narrow; tergites with fine pale brown setulae; sternites sclerotized in middle third and pigmented brown; sternite 5 large, almost square, and with pigmented sclerotized lateral parts that fold ventrally and medially; sternite 6 small and of complicated structure ( Fig. 5C ).

HYPOPYGIUM ( Fig. 5B ). Epandrium small and pale, bearing long surstylus that is curved postero-medially at apex and bearing 3 fine setulae; hypandrium with narrow lateral arms at base (anterior), each broadening caudally and curving ventrally fusing with triangular sclerotized pregonite; postgonite long, narrow and pale and when viewed from posterior aspect it runs close and parallel to basiphallus ending just short of posterior border of epandrium, hence not visible in lateral view; epiphallus clearly separated from distal part of membranous and largely translucent basiphallus; distiphallus pale, mostly membranous and irregularly cylindrical; cercus large and yellow.

Female

As in male, but without secondary sexual characters and in two specimens the scutal vittae are pale brown.

Variation

Other than minor chromatic variation, no significant variation noted in this short series of specimens.

Figures

Fig. 4. Aphaniosoma aegyptium sp. nov., ♂, holotype (CUSLP). A. Habitus, lateral view. B. Head and thorax, dorsal oblique view.

Fig. 5. Aphaniosoma aegyptium sp. nov., ♂, holotype (CUSLP). A. Hind trochanters, posterior view. B. Hypopygium, lateral view. C. Pregenital sternites, ventral view. Abbreviations: See Material and methods. Scale bars: B–C = 0.15 mm.

Fig. 34. Aphaniosoma flavipyga sp. nov., ♂, paratype (SMNHTAU). A. Hypopygium, lateral view. B. Hypopygium, ventral view. C. Sternite 6, ventral view. Abbreviations: See Material and methods.