Taxonomic review of the Sphecapatodes ornata group (Diptera: Sarcophagidae: Miltogramminae), with description of one new species

The genus Sphecapatodes Villeneuve is recorded from China for the first time. The Sphecapatodes ornata group is defined and reviewed, with one new species, Sphecapatodes xuei sp. nov., described, photographed, and illustrated. The current concept of S. ornata Villeneuve, 1912 is shown to be based at least partly on a misidentification. A key to males of the S. ornata group is given. Wing interference patterns (WIPs) are presented for species-level discrimination of miltogrammine sarcophagids for the first time. The genus Sphecapatodes Villeneuve, 1912 is represented in China by two species, S. kaszabi Rohdendorf and Verves, 1980 and S. xuei sp. nov. WIPs can be used for species-level discrimination of miltogrammine sarcophagids.


Background
The flesh fly subfamily Miltogramminae makes up the sister group of all remaining sarcophagids (Pape 1996;Kutty et al. 2010). Miltogrammines are generally considered to be kleptoparasites of solitary bees and wasps, utilizing the stored food (insects, spiders, pollen) that these hymenopterans provide for their own progeny (Pape 1996(Pape , 1998Povolný and Verves 1997;Szpila and Pape 2008), but recent evidence indicates that several species exploit buried carrion, which makes them of importance as forensic indicators in arid areas (Szpila et al. 2010;unpublished). Pape and Kurahashi (1995) mentioned that very few records of Miltogramminae have been published from China probably due to insufficient collecting. The arid climate and geomorphological configuration of northwestern China would seem to provide many different environments suitable to host a large diversity of Miltogramminae. With the aim of discovering more species of this group, we have been engaged in faunal studies in northwestern China, mainly focused on the arid parts, since 2009. While sorting and identifying miltogrammine specimens from the Xinjiang Uygur Autonomous Region, the first author found specimens of the genus Sphecapatodes Villeneuve, which has previously not been recorded from China. Two species of Sphecapatodes were identified, one of which is considered to be new to science.
The genus Sphecapatodes was established by Villeneuve (1912), with S. ornata Villeneuve, 1912 as the type species fixed by monotypy. Séguy (1941) published the North African Sphecapatodes maroccanus as the second species in this genus; however, this species was revised and transferred to Miltogramma Meigen by Pape and Szpila (2012). Rohdendorf and Verves (1980) described Sphecapatodes kaszabi from Mongolia. Pape (1996Pape ( , 1998 treated the genus Turkmenisca Rohdendorf as a junior synonym of Sphecapatodes, thus including additional three species, i.e., S. inornata (Rohdendorf 1975), S. fursovi (Rohdendorf 1975), and S. richterae (Verves 1980). In the present study, we describe one new species, bringing the total of known species of Sphecapatodes to six, three of which belong to the S. ornata group as defined below. The genus Sphecapatodes has its center of diversity in Central Asia, and so far only the type species S. ornata is known from the western Palaearctic, this species being described from Tunisia in North Africa.
The primary aims of this paper are to (i) define and review the S. ornata group; (ii) describe, photograph, and illustrate the new species S. xuei sp. nov.; (iii) provide a key to the known species of the S. ornata group; and finally (iv) use wing interference patterns (WIPs) for the separation of species for the first time in the subfamily Miltogramminae.

Methods
Photographs were taken with a Canon 500D camera (Canon, Inc., Tokyo, Japan) mounted on an Olympus SZX16 stereomicroscope (Olympus Corp., Tokyo, Japan). The images processing software used were Helicon Focus 3.2 (Helicon Soft Ltd, Kharkov, Ukraine) and Adobe Photoshop CS3 (Adobe Systems, Inc., San Jose, CA, USA). Methods for viewing and documenting interference color patterns in thin membranous wings are explained in  and . WIP images were produced using a 70-mm-diameter light-emitting diode (LED) ring light fitted on a stereomicroscope with a working distance of 60 mm, giving an angle between lines of observation and incident light beams of about 40°. Terminology of adult morphology follows McAlpine (1981), and the male terminalia follows Sinclair (2000).

Genus Sphecapatodes Villeneuve Nomenclature
According to Article 30.1.4.4 of the International Code of Zoological Nomenclature (ICZN 1999), ' A compound genusgroup name ending in the suffixes -ites, -oides, -ides, -odes, or -istes is to be treated as masculine unless its author, when establishing the name, stated that it had another gender or treated it as such by combining it with an adjectival species-group name in another gender form.' Therefore, when Villeneuve (1912) described Sphecapatodes and combined this new monotypic genus with the speciesgroup epithet ornata, which is an adjectival word in the feminine form (of the Latin ornatus, -a, -um, meaning decorated), he also fixed the gender of Sphecapatodes as feminine. Rohdendorf (1975), Verves (1986), andPape (1996) are thus in error when treating the genus as masculine. Villeneuve, 1912: 508. Type species: S. ornata Villeneuve, 1912, by monotypy. Turkmenisca Rohdendorf, 1975: 220. Type species: T. inornata Rohdendorf, 1975, by original designation [synonymized by Pape (1996)].

Sphecapatodes ornata group
Diagnosis. The S. ornata group is proposed here on the basis of the following morphological characteristics that differentiate the group from other members of the genus Sphecapatodes: the posterior part of frontal vitta (at vertex) which is three times as broad as its anterior part (just before lunule); frontal bristles that are fine and not crossed; first flagellomere is short, about 1.20× as long as the pedicel ( Figures 1B, 2B, 3B, 4B, and 5B); and male fore tibia, slightly narrower in basal one third. The S. ornata group consists of all the known species of Sphecapatodes with the exclusion of the three originally described in Turkmenisca, but the latter may well be paraphyletic with regard to the former as they have not been shown to share any synapomorphies, hence, we maintain the synonymy established by Pape (1996).
Redescription. (Based on the newly collected specimens from Xinjiang, photos of type specimens as well as the original description in Russian). Male. Body length 6.10 to 7.00 mm.
Eyes, bare. Fronto-orbital, parafacial plates, and postocular strip black with silvery white pollinosity; parafacial plate with rows of fine setulae, denser at the lower part; fronto-orbital plate with one row of setulae. Frontal vitta black, with thick silvery white pollinosity, becoming narrow at the anterior (lower) part; frons at vertex 0.40 to 0.45 × head width; frontal vitta with several fine setulae; frontal row of 8 to 12 bristles; outer vertical bristle differentiated from postocular bristles and about 0.60× as long as inner vertical bristle, proclinate orbital bristles four (two strong), reclinate orbital bristle one. Ocellar bristles directed laterally. Gena ground color brown, with sparse and short black setulae and silvery gray pollinosity, 0.18 to 0.20× eye height in lateral view. Antenna dark brown, first flagellomere 1.20× as long as pedicel; arista black brown, bare, or micro-pubescent, basal one fifth swollen; facial ridge with one or two fine setulae at the lower part. Palpus orange, slightly expanded at the apex.
Wing hyaline, with one faint apical spot; subcostal sclerite and basicosta bare and yellow; tegula dark yellow, with black setulae; costal spine not differentiated; vein R 1 bare; several fine black setulae at node of R 4 + 5 -R 2 + 3 ; wing WIP ( Figure 8A) with a clearly demarcated green band between an inner magenta band and an outer blue/magenta band, with a narrow yellow band along posterior wing margin, and with a green spot on the apical part (shown with a star in Figure 8A).
Legs dark, claws and pulvilli small; fore femur posteriorly with numerous long bristles, one ventral row of bristles, fore tibia slightly narrower in basal one third, with one median posteroventral, one subapical anterodorsal and one dorsal bristle, fore first tarsomere with dense setulae on the ventral surface at base and with sparse setulae on the anteroventral and posteroventral surfaces ( Figure 7A,B); all tarsomeres of fore leg with one elongate, slender seta apico-distally; mid-femur with one row of anteroventral bristles, three anterodorsal, and two apical posterodorsal bristles, and mid-tibia with three anterodorsal, one submedian ventral, and one row of posterodorsal bristles; hind femur with dense setulae on anteroventral and ventral surface, one dorsal row of bristles, hind tibia with one anterodorsal row of bristles, and four ventral and four posterodorsal bristles.
Abdomen with dense gray pollinosity; tergites 1 + 2 with 3 distinct black spots, the median one large, tergite 3 with a black median stripe, and with one pair of median marginal bristles; tergite 4 with inconspicuous median spot, the lateral spot small, and with a complete row of marginal bristles; sternites 1 and 2 with long and dense setulae. Terminalia: Cercus small and gently curved distally, surstylus with an oval rounded tip in lateral view, phallus parallel-sided distal to the dorsal plate and rounded apically ( Figure 6).
Female. Body length 6.00 to 7.00 mm. Differs from male in the following characters: Head. Frons at vertex 0.46 to 0.49× as broad as head width. Thorax, scutum, and scutellum with gray pollinosity. Chaetotaxy: acrostichals 3(4) + 1. Wing without apical spot. Fore tibia not narrow in basal part, with one posterior and three weak anterodorsal bristles; mid-tibia with one ventral and one posterior bristle; hind tibia with two ventral and three posterodorsal bristles. Abdominal tergites, 3 to 5 with complete marginal rows, tergite 3 with an inconspicuous black median stripe; tergites 4 and 5 without median black spot; sternites 1 and 2 with sparse setulae (two large).
Specimens examined. Mongolia: holotype ♂ and paratype ♀ (from photographs), Bayan Khongor Aimak, Ekhin  Biology. The female specimen documented for the present paper ( Figure 3B,C) has numerous pollen grains sticking to the setulae of the proboscis and on the fore legs, strongly indicating that the adults of this species have a habit of visiting flowers.
Remarks. As mentioned under S. ornata (below), we consider Rohdendorf's (1975) concept of 'Sphecapatodes ornatus' to be a misidentification, as at least the specimens from ZMUM which Rohdendorf named 'S. ornatus' are conspecific with S. kaszabi. Comparing the original description of S. kaszabi as well as the photographs of the holotype with newly collected specimens, we were unable to find differences justifying more than a single species, which has led us to consider all the examined specimens to be conspecific.
Sphecapatodes ornata Villeneuve (Figures 4, 7C,   anterior part; frons at vertex 0.45× head width; frontal row of 8 to 12 bristles; outer vertical bristle differentiated from postocular bristles and about 0.75× as long as inner vertical bristle, and proclinate orbital bristles four (two strong) and reclinate orbital bristle one. Ocellar bristles directed laterally. Gena ground color dark red, with sparse and short black setulae and silvery gray pollinosity, 0.15× eye height in lateral view. Antenna grayish brown, first flagellomere 1.20× as long as pedicel; arista black brown and micro-pubescent, basal one fifth swollen; facial ridge with three fine setulae at the lower part. Palpus orange, slightly expanded at the apex.
Legs dark, claw and pulvillus small; fore femur posteriorly with numerous long setulae, one ventral row of bristles, fore tibia slightly narrower in basal one third, with one median posteroventral bristle, one subapical dorsal bristle, five anterodorsal bristles, fore first tarsomere with dense setulae on the anteroventral surface ( Figure 7C); mid-femur with one row of ventral bristles, one apical posterodorsal and one apical posterodorsal bristles, mid-tibia with two anterodorsal, one submedian anteroventral, and two posterior and two posterodorsal bristles; hind femur with one dorsal row of bristles, hind tibia with one anterodorsal row of bristles, and two anteroventral and two posterodorsal bristles.
Abdomen tergites 1 + 2, tergite 3 and 4 with complete rows of marginal bristles, tergites 1 + 2 with 3 distinct  black spots, the median one large, median spots of tergites 3 and 4 smaller than the lateral ones.
Distribution. Tunisia. Remarks. S. ornata was recorded from Armenia, Azerbajdzhan, Egypt, Tajikistan, Turkmenistan, and Uzbekistan by Rohdendorf (1975) and Pape (1996), but these records appear to be based on misidentifications. It is noteworthy that Rohdendorf (1975) did not have access to Villeneuve's original material of S. ornata, and his redescription of this species deviates strikingly from the syntypes examined for the present paper in mentioning three or four long, fine setulae along the posterior surface (der Außenseite) of the male fore tarsus. The morphological similarities between the species Rohdendorf (1975) redescribed as S. ornatus and the species S. kaszabi appear to be consistent by careful comparison of material identified by Rohdendorf, that is to say, the S. ornatus Rohdendorf (1975) redescribed is in fact S. kaszabi (see remarks under this species).
Sphecapatodes xuei sp. nov. (Figures 5, 9, 7D, and 8D) Description. Male. Body length 6.00 mm. Eyes, bare. Fronto-orbital, parafacial plates, and postocular strip black with silvery white pollinosity; parafacial plate with one row of fine setulae; fronto-orbital plate with one or two fine setulae. Frontal vitta black, with  thick silvery white pollinosity and several fine setulae, becoming narrow at the anterior (lower) part; frons at vertex 0.43× head width; frontal row of six or seven bristles; outer vertical bristle differentiated from postocular bristles and about 0.60× as long as inner vertical bristle, proclinate orbital bristles two, reclinate orbital bristle one. Ocellar bristles directed laterally. Gena ground color brown, with sparse and short black bristles and silvery gray pollinosity, about 0.15× eye height in lateral view. Antenna dark brown, first flagellomere 1.10× as long as pedicel; arista bare and black brown, swollen in basal one fifth; facial ridge with one or two fine setulae at the lower part. Palpus orange, slightly expanded at the apex.
Wing hyaline, with one faint apical spot; subcostal sclerite and basicosta bare and yellow; tegula dark yellow, with black setulae; costal spine not differentiated; vein R 1 bare; several fine black setulae on dorsal surface at node of R 4 + 5 to R 2 + 3 ; wing WIP ( Figure 8D) with a broad and somewhat ill-defined magenta band (tinged with yellow) near the posterior margin extending from wing tip to CuA1 and two larger and almost triangular magenta areas proximal to the middle of cell R 4 + 5 and distally in the cubital cell.
Legs dark, claws and pulvilli small; fore femur posteriorly with numerous long setulae, one ventral row of bristles, fore tibia slightly narrower in the basal one third, with one median posteroventral, one subapical dorsal, and three anterodorsal bristles, fore first tarsomere with the usual dense setulae on the ventral surface at the base ( Figure 7D) and with sparse setulae on the anteroventral and posteroventral surfaces; midfemur with one row of anteroventral bristles and two apical posterodorsal bristles, mid-tibia with one anterodorsal, one ventral, one posterior and one posterodorsal bristles; hind femur with one row of ventral bristles, hind tibia with one row of anterodorsal bristles (two bristles larger than the others) and one posterodorsal row of bristles (three bristles larger than the others) and three anteroventral bristles.

Female. Unknown.
Remarks. The new species is very similar to S. kaszabi but can be separated from this species by the characters given in the key.
Etymology  Rohdendorf (1975) and Verves (1980) -The width of the posterior part of frontal vitta about 3.0× as broad as its anterior part, frontal bristles fine and not crossed……..……………………2 2. Proclinate orbital bristles 2, gena ground color brown, presutural acrostichal bristles 1 or 2, dorsocentrals 2 + 3, fore first tarsomere with sparse setulae on the anteroventral surface ( Figure 7A,B) ……………………………. 3 -Proclinate orbital bristles four (two strong), gena ground color dark red, presutural acrostichal bristles absent, dorsocentrals 3 + 4, fore first tarsomere with dense setulae on the anteroventral surface ( Figure 7C) ………… S. ornata Villeneuve 3. Fore first tarsomere with one elongated ventral seta ( Figure 7D), parafacial plate with about ten setulae ( Figure 5C), the black spots on tergites 1 to 4 almost fused together ( Figure 5E), wing interference pattern ( Figure 8D) with only a single, rather ill-defined magenta band along the posterior margin, surstylus with tip curving posteriorly, phallus apically slightly broadened in lateral view (Figure 9)………………………………………………….…… S. xuei sp. nov. -Fore first tarsomere with four elongated ventral setulae ( Figure 7A), parafacial plate with more than 20 setulae ( Figure 4C), black spots on tergites 1 to 4 distinct ( Figure 4E), WIP ( Figure 8A) with a clearly demarcated green band between an inner magenta band and an outer blue/magenta band, surstylus with apex straight (not curving posteriorly), phallus apically narrower in lateral view ( Figure 6A,B)……………………………… S. kaszabi Rohdendorf and Verves Pape (1996) mentioned a number of character states, which together will both diagnose and define the genusgroup taxon Sphecapatodes. He also stated that 'The genera Sphecapatoclea and Sphecapatodes are probably sister groups, and […] they could as well be lumped into one genus.' Judging from the diagnoses provided, this was based on the sharing of a dense silvery microtomentose male frontal vitta, laterally directed ocellar bristles, and subequal fringes of the metathoracic spiracles. This leaves only two autapomorphies for the genus Sphecapatodes, both confined to the male: (1) elongated setae ventrally on the fore first tarsomere (Figure 7) and (2) wing with apical wing spot ( Figures 2D, 4D, and 5D). Pape (1996) noted that 'exceptions occur' with regard to the presence of the wing spot. However, the only species of Sphecapatodes without the male wing spot is S. inornata, and this seems to be partly due to a misrepresented or misprinted illustration (Rohdendorf 1975, figure 160a, b), as Rohdendorf's key explicitly states that the wing margin of the male is very slightly light brown in the area of the apical spot of S. fursovi [sehr schwach hell gebräunt an der Stelle des Apikalfleckes der vorigen Art (p. 220)]. With only the holotype of S. inornata known, more specimens are needed to fully evaluate the wing spot character for this species. As evident from the present paper, the male fore tarsal ornamentation in Sphecapatodes is rather diverse and most markedly developed on the first tarsomere, and the elongated setae may be either ventral or a combination of anteroventral + posteroventral, obscuring homology assessment. WIPs were recently discovered by  as a potential new character system in the transparent cuticle of extremely thin membranous insect wings, especially small Hymenoptera and Diptera, and the method has proven useful for the separation of species (Buffington and Sandler 2011;Hansson 2011;). There is a paucity of WIP data in the Cyclorrhapha, although WIPs represent an intriguing model of morphological diversity that might increase our understanding of evolutionary trends .  demonstrated the usefulness of WIPs to separate species in the genus Achrysocharoides Girault (Hymenoptera: Eulophidae), where several species also displayed sexual dimorphism in these patterns. Conversely, Hansson and Shevtsova (2012) demonstrated that species of the genus Omphale Haliday (Hymenoptera: Eulophidae) do not have sexually dimorphic WIPs. The current data are very preliminary due to limited material and in particular the lack of females, but as evident from Figure 8A,C, there is no difference in the male and female WIPs of S. kaszabi, and all three species are easily identified from their WIP. This indicates that WIPs have the potential both of being a useful tool for correctly associating male and female specimens, which is a well-known problem in many sarcophagid groups (Hall et al. 2009;Zhang et al. 2013), and as an additional species-specific character complex. Obtaining WIP data in the form of digital photographs is remarkably simple (Buffington and Sandler 2011; ) and WIPs might therefore be a new and rapid way to identify adult sarcophagids and associate males and females.

Conclusions
The S. ornata group is defined and reviewed, with one new species, S. xuei sp. nov., described, photographed, and illustrated. There is no difference in the male and female WIPs of S. kaszabi, and all three species are easily identified from their WIP. WIPs can be used for species-level identifications in this genus and should be investigated further as a potentially useful identification character for other sarcophagid groups.