Callomyia saibhira Chandler, 1976

Tkoc, Michal & Rohacek, Jindrich, 2014, Diversity, distribution and biology of Romanian flat-footed flies (Diptera, Opetiidae and Platypezidae) with taxonomic notes on Callomyiasaibhira Chandler, ZooKeys 459, pp. 95-118 : 100-103

Taxon classification Animalia Diptera Platypezidae

* Callomyia saibhira Chandler, 1976 Figs 9-10

Material examined.

1 ♂, 1. vi. 2008, Banat, Sfânta Elena, 4 km NE, Kulhavá skála, Vranovec cave (Figure 17), 300 m a.s.l., 44°42'12"N, 21°43'52"E, sweeping vegetation along brook, JR leg.

Differential diagnosis. Male of Callomyia saibhira differs from Callomyia amoena and Callomyia elegans by having darker halteres that are not orange (brown with knob black). Callomyia speciosa have longer arista and shorter first flagellomere and upper part of pleura is not so silvery grey dusted as in Callomyia saibhira . From its most similar species, Callomyia dives Zetterstedt, 1838, it differs by a clear wing membrane, brown palpus and different genitalia, basal lobe of gonopod is shorter (Figure 10). Females have unique abdominal coloration: tergites 1-4 (T1-4) are orange yellow with narrow brown hind margins on T2-4, only T5 is black, T6 and terminal segments are silvery grey dusted.

Redescription.

Male. Body length 4.1 mm. Wing length 3.8 mm.

Head black with silvery grey dusting. Antenna dark brown, scapus with dorsal seta reaching to tip of pedicel, pedicel with one strong dorsal seta reaching to the middle of first flagellomere, both sides of pedicel with 3 short setae, 1 short seta on ventral position. First flagellomere conical, twice as long as pedicel. Second and third flagellomere long. Arista half of antennal length. Two pairs of small frontal setae. Ocellar tubercle dull brown, with one pair of ocellar setae and one pair of small postocellar setae. Postocular setae long, their apices visible in anterior view. Face and parafacial bare, silvery grey dusted. Gena, occiput and postgena with long black setae. Occiput black, silvery grey dusted. Palpi brown with short black setae, proboscis brown with pale pubescence.

Thorax velvet black with silvery grey dusted areas. Two very inconspicuous median dorsal grey stripes between dorsocentral and acrostichal setae ending in anterior two thirds of scutum. Posterior sides of scutum silvery shining. Pleural sides of thorax without setae, silvery grey coloured. All thoracic setae black. Uniserial row of acrostichal setae, two rows of about 10 dorsocentral setae. Humeral callus with top brownish, with 2 humeral setae; 4 small posthumeral setae. One postalar seta. Notopleural group composed of 6 setae: 1st long, 2 nd– 4th short, 5 th– 6th long. Notopleural area silvery grey dusted. Two long presutural and 4-5 small postsutural setae. Scutellum black, with 2 prominent scutellar setae on each side. Haltere brownish with knob black.

Wing hyaline with brown to dark brown veins. Subcostal cell (sc) yellow tinted and with microtrichia. Wing surface not uniformly covered with microtrichia, microtrichia present on anal lobe, posterior and distal part of wing. First longitudinal vein (R1) bearing 9-10 spines. Anterior (r-m) and posterior (dm-cu) crossveins present. Costal cell (c) equal to sc in length. Posterior crossvein (dm-cu) twice as long as distal part of the fifth longitudinal vein (CuA1). Anal cell (cup) elongated, its length about three times portion of anal vein (A1+CuA2) beyond it.

Legs slender, brown, slightly silvery shiny. All coxae silvery dusted with black setae, yellow distally. Fore femur with longer fine ventral setae distally. Fore femur with 1 oxhorn seta. Apices of femora and basal parts of tibiae (= “knees”) yellow. Fore tibia with 1 anteroventral spur. Fore tarsomeres I−II yellow. Mid tibia bearing short dorsal seta above middle (anterodorsal seta absent) and two long ventral apical spurs. Hind femur of the same width as hind tibia. Hind tarsomere I with ventral seta above middle.

Abdomen black with silver-grey coloured markings. Setae on abdomen fine and black. Tergites 1 and 2 (T1+2) more setulose than the others, T3+T4 sparsely setulose. T1 black, its anterior half shiny silvery grey in lateral view. T2 black with silvery grey marking on posteroventral area. In lateral view this marking occupies posterior third of T2. T3 black, with similar (but smaller) marking, mainly on ventral part. T4 black, with silvery grey marking on posteroventral area occupying posterior two thirds in lateral view. T5 black. T6 black with posterior border grey. T7 small, entirely grey. Sternite 8 also grey, without setae.

Genitalia (Figure 10) with epandrium grey, cercus brownish, surstylus and hypandrium shiny amber-brown. Paramere (postgonite) slightly curved dorsally with base narrower, its broader apical part slightly tapered towards the rounded apex. Aedeagus (phallus) broad in lateral view, its dorsal apex with sharp tooth anteriorly, bluntly rounded posteriorly. Hypandrium with small inner hypandrial lobe (ihl) sub-basal to gonopod. Gonopod (hypandrial lobe) trifid, with shorter basal gonopodal lobe (bgl) and longer terminal part deeply bifid forming two slender apical lobes. Surstylus with basal part narrower than its apical rounded part, the latter with a digitiform dorsal process. Terminal lobe of epandrium gradually tapered and slightly curved, covered by setulae and with 2 longer setae. Ventral part of epandrium with 5 prominent setae two smaller setae and two additional smaller setae positioned more ventrally. Cercus covered by microtrichia and with short curly setulae on apex.

Female. Not studied, for description see Chandler (1976, 2001).

Distribution.

Palaearctic species. Hitherto recorded only from Bulgaria ( Chandler 1976) and the Far East of Russia ( Shatalkin 1985). New record for Romania.

Biology.

Unknown. The larvae of other European Callomyia species develop on mycelia under bark of various trees (see above under Callomyia amoena ). The adult male examined was swept from vegetation close to a cave along a small brook (Figure 17). The known flight period in Europe is in VI.

Comments.

This is the second specimen and first male of the species from Europe. Other known material (♂♂ and ♀♀) was collected in the Far East of Russia, Amur region ( Shatalkin 1985). It is similar to Callomyia dives in the morphology of males, but the silver coloration on the thorax and abdomen is less developed. Also, the basal lobe of the gonopod (bgl) is shorter (Figure 10). This species seems to have an inland distribution, whereas Callomyia dives is found mostly on islands or close to coastal zones of Europe.

Chandler (2001) figured genitalia of an Amur specimen collected by Shatalkin. However, the genitalia of our specimen do not entirely fit into the description and figure of Chandler (2001). The main differences appear to be as follows (see Figure 10): presence of inner hypandrial lobe (ihl) positioned sub-basally to gonopod (this character is present in more Callomyia species, but usually omitted in the descriptions and figures in the literature); paramere (postgonite) is wider in lateral view, curved dorsally, with narrow basal part; morphology and position of basal gonopodal lobe (bgl) is very similar to that of Chandler (2001), but the bifurcation of terminal part of gonopod is more profound; the apical part of surstylus is less rounded and its basal part is only slightly narrower than apical part; cerci have shorter curly setulae.