New synonymies and new combinations of Muscidae from China (Diptera, Muscoidea)

Abstract New synonymies and new combinations are proposed, based mainly on the study of type materials. They are as follows: Helina sarmentosa Fang & Fan, 1993 = Helina dianica Qian & Feng, 2005, syn. n.; Helina dianxiia Xue and Li, 2002 = Helina aureolicolorata Feng & Xue, 2002, syn. n.; Myospila lenticeps (Thomson, 1869) = Helina magnimaculata Feng, 1995, syn. n.; Spilogona angulisurstyla (Xue & Xiang, 1998), comb. n.; Spilogona apicicauda (Xue, Wang & Tong, 2003), comb. n.; Hebecnema arcuatiabdomina (Feng & Fan, 2001), comb. n.

Helina includes so many species that it is an intimidating task to undertake research on, or even to identify the species correctly. Furthermore, many specialists consider that Helina is a ''catch-all'' repository for species that cannot be assigned elsewhere (Hennig 1965, Wang et al. 2008. The genus needs to be fully revised. In this paper, new synonymies and new combinations are proposed, based mainly on the study of type materials.

Helina sarmentosa
Redescription. MALE. Body length 8.5-9.5mm. Eye with dense and long hairs; frons about 1.3-2.0 times as wide as the width of anterior ocellus; frontal setae reaching ocellar triangle; fronto-orbital plate and parafacial with silveryish-grey pollinosity; parafacial bare, about 1.5-2.0 times as wide as postpedicel; antenna black, postpedicel about 2.6-3.0 times as long as broad, about 1.8 times as long as pedicel, arista plumose, the longest hair about equal or slightly longer than postpedicel width; gena and postgena with black hairs, gena with 5 rows of subvibrissal setae in anterior margin, genal height about 2/5 times of eye height; proboscis stout, prementum about 2.0 times as long as height; palpus black, slightly flat in distal half. Thorax ground-color black, scutum with four dark vittae in posterior view, acr 0+1, 9 rows of irregular fine setae between two dc rows, dc 2+4, ia 0+2, pra absent; anepisternum with hairs around anepisternal setae, meron with hairs around the lower margin of posterior spiracle, scutellum with black hairs in the lateral margin; basisternum, proepisternum, anepimeron, katepimeron bare; katepisternal setae 2+2, spiracles dark brown. Wing hyaline, brownish, with heavier color in the basal part and around veins; costal spine inconspicuous, radial node bare; veins R 4+5 and M conspicuously diverging distally, crossveins r-m and dm-cu lightly clouded, crossvein m-m sinuate; calypteres yellowish; halteres brownish-yellow. Legs black; fore tibia with 2-4 p; basal half of mid femur with row of 8-10 pv (stout towards distally), distal half with 2 or 3 slender setae, mid tibia with 1 or 2 ad and 6 or 7 developed p, the length of longest seta about 3/5 of width of tibia; hind coxa bare on rear surface, hind femur with 5-7 strong setae on distal half, hind tibia with 7-10 av, 3-5 developed ad and 6-9 p. Abdomen ground-color black, with dense greyish-blue pollinosity, tergites 2 to 4 with one large dark lateral patch on each side, tergites 4 and 5 with posterior marginal setae, tergite 5 with irregular discal setae, sternite 1 with hairs.
Remarks. Both Helina sarmentosa and H. dianica can be easily separated from the other Helina species by mid and hind tibiae with very long and stout setae. Having examined the holotypes of both nominal species, we were unable to find differences justifying their separation, which has led us to consider all the examined specimens to be conspecific.  Xue and Chao (1998) and can be easily distinguished from other Helina species by the slightly shortened arista, pra absent, katepisternal setae 1+1, veins R 4+5 and M not diverging distally, abdomen with trapezoid patches, sternite 1 bare, sternite 5 broad and short, cerci long and distal sharped, surstyli not expanded distally but sharp in lateral view. However, these diagnostic characters are practically identical with the generic characters of Spilogona. Our analysis of the paratypes of H. angulisurstyla revealed a similar external morphology; especially the male genital structures with species in the genus Spilogona. Consequently, we suggest the following new combination: Spilogona angulisurstyla.
Distribution. China (Xinjiang). ( Remarks. Diagnostic characteristics (arista short; pra absent; katepisternal setae 1+2; costa with distinct comb-like rows on the front margin, vein m-m straight; mid tibia with 2 ad and 2 p; tergites 3 and 4 with one pair dark patches, sternite1 bare; surstyli slender, the lateral margin of cerci curved in distal half, apical of cerci sharp, sternite 5 broad and short) of the holotype indicate that it belongs to Spilogona.

Spilogona apicicauda
Distribution. China (Qinghai). ( Coxae and trochanters brownish-yellow; femora and tibiae brownish-yellow, tarsi black, distal part of tarsi with yellow rings; fore tibia without p; basal third of mid femur with 4 pv (short and stout distally), mid tibia with 3 p, distally with 1 p; hind coxa bare on posterior surface, hind femur with complete rows of av and p, 1 av distally. Abdomen slightly dark yellow, with thin pollinosity, without distinct stripes and round patches, syntergite 1+2, tergites 3 and 4 with narrow posterior marginal stripes, tergites 3 to 5 with median marginal setae; tergite 6 and sternite 1 bare, sternites 2 and 3 square-shaped. FEMALE. Unknown. Remarks. The genus Hebecnema Schnabl, 1889 resembles the genus Helina but differs from it by the following characters: abdomen always without paired spots; fronto-orbital plate narrow, always narrower than antenna width; head in lateral view slightly flat on upper part; surstyli always slender.

Hebecnema arcuatiabdomina
According to the original descriptions and illustrations of H. arcuatiabdomina given by Feng and Fan (2001), we can confirm that this species belongs to Hebecnema.