Sphecomyia

M. Moran, Kevin & H. Skevington, Jeffrey, 2019, Revision of world Sphecomyia Latreille (Diptera, Syrphidae), ZooKeys 836, pp. 15-79 : 21-22

Sphecomyia stat. rev. Figs 1, 2 A–F, 2J, 3B, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27

Sphecomye Latreille 1825: 495.

Sphecomyia Latreille in Bory 1829: 545 (also Latreille 1829: 495) - Williston 1886: 256; Osburn 1908: 14; Shannon 1925: 43; Curran 1932: 8; Stone 1965: 612; Weisman 1965: 265, 1966a: 50, 1966b: 189; Vockeroth and Thompson 1987: 736. Type species: Chrysotoxum vittatum Wiedemann 1830 by subsequent designation of Macquart 1842.

Epopter Wiedemann 1830: 91. Synonymy in Evenhuis and Pont 2013: 28. Type species: Psarus ornatus Wiedemann, 1830 [= Sphecomyia vittata (Wiedemann, 1830)], by monotypy.

Tyzenhausia Gorski 1852: 172. Synonymy in Wahlberg, 1854: 155. Type species: Tyzenhausia vespiformis Gorski 1852, by original designation.

Eurhinomallota Bigot 1882: 78. Type species: Eurhinomallota metallica Bigot 1882 by original designation. Syn. n.

Eurhynomallota Bigot 1883: 225. Unjustified emendation of Eurhinomallota .

Eurinomallota Kertész 1910: 62. Unjustified emendation of Eurhinomallota .

Brachymyia Williston 1882a: 77 - Williston 1882b: 330; Shatalkin 1975: 131. Type species: Brachymyia lupina Williston 1882, by original designation. Syn. n.

Diagnosis.

Male dichoptic. Both sexes with bare, medial vitta extending ventrally from oral margin, usually to base of antenna, except interrupted by pruinosity at facial tubercle in S. interrupta and only extending to facial tubercle in S. metallica . Gena bare. Katepimeron bare. Scutellum with at least anterior margin densely pruinose. Narrow intersection of vein R1 with vein C. Anterior ventral half of vein C before crossvein h without setae. Distance between apices of veins R1 and R2+3 longer than distance between apices of veins R2+3 and vein R4+5+M1. Abdominal pile erect. Phallapodeme banana-shaped.

Redescription.

Male. Body length: 9.2-17.1 mm. Wing length: 7.7-12.1 mm. Head. Face black, bare, concave beneath antenna, produced downwards and pruinose except with bare, medial vitta extending from oral margin, usually to base of antenna, except interrupted by pruinosity at facial tubercle in male S. interrupta Moran sp. n., and only extending to facial tubercle in male S. metallica (Bigot, 1882) or just beyond in the female; gena broad, as broad or broader than long, bare, shiny; anterior tentorial pit short, extending along ventral one-third of eye, pilose; frontal prominence distinct; frons broad, of variable size, at least partially pruinose; vertex variable in shape and pruinosity; ocellar triangle pilose, small; eye bare; male dichoptic; antenna length variable; kidney-shaped basoflagellomere, except sub-triangular in S. brevicornis , S. vespiformis and S. vittata , with bare arista dorsally placed.

Thorax. About as long as broad, short pilose except in Sphecomyia metallica ; postpronotum pilose; proepimeron pilose; anterior anepisternum bare, posterior anepisternum pilose; scutum with or without pruinose vittae; scutellum with at least anterior margin densely pruinose, without apical sulcus and with ventral pile fringe; katepisternum bare anteriorly, discontinuously pilose posteriorly with broadly separated patches; anepimeron with anterior portion pilose, and dorsomedial and posterior bare; katepimeron bare; metathoracic pleuron bare; without hypopleural pile at the base of the posterior thoracic spiracle; meron bare, except variable pilose in S. vespiformis ; metathoracic spiracle about same size as flagellum; metasternum pilose; postmetacoxal bridge incomplete; plumula simple, elongate, short, not reaching calypteral margin; calypter yellow.

Legs. Coxae pilose anteriorly, bare posteriorly; hind coxa pruinose anteriorly; metafemur narrow, at most slightly swollen, without basoventral setose patch; metatibia transverse apically, rounded basoventrally.

Wing. Hyaline; stigmatic crossvein present; crossvein r-m at outer fourth of cell dm; anterior ventral half of vein C before crossvein h without setae (Fig. 3B); narrow intersection of vein R1 with vein C (Fig. 3B); distance between apices of veins R1 and R2+3 longer than distance between apices of veins R2+3 and R4+5+M1 (Fig. 3B); cell r2+3 open; vein R4+5 straight; vein R4+5+M1 no longer than crossvein h; vein M2 absent; vein CuP+CuA short, curved.

Abdomen. Oval, slightly longer than broad, often with pruinose bands; abdominal pile erect.

Male genitalia. Surstyli symmetric; aedeagus segmented, with phallapodeme separated from basiphallus and distiphallus; phallapodeme banana-shaped (Fig. 2 A–O); well-developed ctenidion.

Female.

As in male, except for usual sexual dimorphism.

Distribution.

13 Nearctic (12 Western, 1 Eastern) and 3 Palaearctic species.

Remarks.

Latreille (1825) first referenced the genus in French vernacular as Sphecomye based on specimens collected in Carolina by D. Bose. No description was included, nor was a specific epithet assigned to the specimens, thus the name is considered unavailable. Stark (1828) provided a translation from French vernacular as Sphecomyia , but as it referenced Latreille (1825) it still is not considered available. Sphecomyia is first made available in Latreille (1829) in which description of the genus is provided. Macquart (1842) designated Chrysotoxum vittatum Wiedemann as the type species by monotypy.

In this paper, Sphecomyia is redefined as the monophyletic unit of species within Criorhinina that possess the following characters: a bare, medial vitta extending ventrally from the oral margin in both sexes, a bare gena, a bare katepimeron, a scutellum with at least anterior margin densely pruinose, an anterior ventral half of vein C before crossvein h without setae and a narrow intersection of vein R1 with vein C. While the combination of characters used to define Sphecomyia is unique, the subtribe Criorhinina is rife with homoplasy and the presence of one or more of these character states without all the others should not be taken as an indication a species belongs in Sphecomyia .

Brachymyia Williston, 1882 and Eurhinomallota Bigot, 1882 are newly synonymized with Sphecomyia as the type species of both genera fall within this definition and are combined with it as a result of this change. This decision is further supported by molecular evidence showing a close relationship with Sphecomyia , i.e., the present COI gene tree and a multi-gene molecular phylogeny of the Criorhinina which will be presented in an upcoming paper. It is the authors opinion that combination with Sphecomyia , as opposed to resurrecting the concept as a monotypic genus, serves to emphasize its relationship with the group.

There are three major, monophyletic lineages of Sphecomyia . The vittata group, composed of the species with pruinose vittae on the scutum, i.e., S. brevicornis , S. interrupta sp. n., S. sexfasciata Moran sp. n., S. vespiforme , and S. vittata . Secondly, the pattonii group comprised of species with broadened fore tarsi and without pruinose vittae on the scutum, i.e., S. aino (Stackelberg, 1955), S. cryptica Moran sp. n., S. dyari , S. hoguei Moran sp. n., S. oraria Moran sp. n., S. pattonii , S. pseudosphecomima Moran sp. n., S. tsherepanovi (Violovitsh, 1973), and S. weismani Moran sp. n. The third group comprises only one species, Sphecomyia metallica , which has a completely pruinose scutum. S. metallica shares several characters with the vittata group. It has elongated surstyli, with a rounded baso-ventral lobe, reminiscent of the vittata group and it lacks the broadened fore tarsi of the pattonii group. Morphological characters of Sphecomyia are discussed in greater detail in the morphology section (see below).

Also of note, Shatalkin (1975) redefined Brachymyia as representing the species of Criorhina which lack a ventral scutellar fringe and possess hypopleural pile. The type of Brachymyia , Sphecomyia metallica , does not fit this generic definition as it has a ventral scutellar fringe and lacks hypopleural pile. Neither Criorhina berberina (Fabricius, 1805) nor the other species Shatalkin combined with Brachymyia are closely related to the type. Definitions of other criorhinine genera might change after this work.