Rossimyiops Mesnil
Creators: name: Cerretti, Pierfilippo
name: Biase, Alessio De
name: Freidberg, Amnon
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Tachinidae
Rossimyiops

description: Rossimyiops Mesnil
Rossimyiops Mesnil, 1953: 145. Type species: Rossimyiops whiteheadi Mesnil, 1953 (by monotypy). References: Verbeke 1962: 117 [notes on systematic position]; Crosskey 1980: 830 [Afrotropical catalogue]; Crosskey 1984: 238 [key to Afrotropical tachinid tribes and genera].
Mesnilomyia Kugler, 1972: 103. Type species: Mesnilomyia magnifica Kugler, 1972 (by original designation). Syn. nov. References: Kugler 1978: 86 [systematic position of Plesina Meigen and Mesnilomyia]; Tschorsnig and Richter 1998: 760, 772 [key to Palaearctic genera of Tachinidae]; Zeegers 2007: 409 [keys for the identification of specimens of Afrotropical Mesnilomyia: modified from Crosskey 1984: 237 (Imitomyiini and Dufouriini)].
Persedea Richter, 2001: 25. Type species: Persedea exquisita Richter, 2001 (by original designation). Syn. nov.
Diagnosis. Small flies 2–6 mm in length. Male vertex extremely narrow, and frontal vitta, near vertex, concealed by medial margin of fronto-orbital plate (Fig. 4); female vertex larger with 2 or more proclinate orbital setae. Occiput with black setulae only. Anterior and posterior lappets of metathoracic spiracle about equal in size (Fig. 24). Postmetacoxal area membranous. Mid-dorsal depression on abdominal syntergite 1+2 not extended posteriorly to distal margin of that segment. Marginal setae on tergites 3–5 “shifted” anteriorly into sub-discal position. Dorsolateral lobes of distiphallus well developed and “shifted” anteriorly. Surstylus distally bent posteriorly. Parasitoids of Embioptera.
Redescription. Body length: 2–6 mm. Head (Figs. 2–5, 8, 11–15, 17, 20, 23, 28, 29, 36–38, 42): Compound eye bare. Vertex at its narrowest point about 0.1 (male), 0.50–1.15 (female) times as wide as compound eye in dorsal view. Lateral vertical seta usually not differentiated from postocular row (well developed only in R. whiteheadi female). Ocellar seta from well developed to very short and hair-like. Frontal setae reaching anteroventrally at most to middle of pedicel. Male frontal vitta, near vertex, concealed by medial margin of fronto-orbital plate (Fig. 4). Dorsal orbital setae usually not differentiated in male, 1 or 2 in female. Male without, female with 2–4 proclinate orbital setae. Parafacial bare. Parafacial at its narrowest point 0.50–1.25 times as wide as postpedicel. Facial ridge slightly concave or straight. Facial ridge with slender and decumbent setae on ventral 0.2–0.4. Face more or less visible in lateral view. Ventral facial margin from not visible to well visible in lateral view anterior to vibrissal angle. Postpedicel 1.5–3.5 times as long as pedicel. Arista bare, thickened on basal 0.2–0.4. First and second aristomeres short. Gena in profile not more than 0.4 times as high as compound eye (height measured in the same vertical plane as height of head). Genal dilation well developed. Occiput with black setulae only. Prementum 2–10 times as long as diameter at mid length. Labella not elongated, posterior extensions developed only in female of R. longicornis and R. whiteheadi. Palpus subcylindrical or slightly clavate. Thorax (Figs. 8, 18, 21, 22, 24, 38, 39): black to yellow in ground colour. Scutum with or without reflecting microtrichia, if present, presutural area with three longitudinal dark vittae. Prosternum and proepisternum bare. Postpronotum with 2 or 3 setae arranged in a more or less straight line. Scutum with 2–3 presutural dorsocentral setae, 3–4 postsutural dorsocentral setae, 2–3 postsutural intra-alar setae. Katepisternum with 1–2 setae. Katepimeron bare. One short anepimeral seta. Scutellum varied from black to yellow, with 2–3 pairs of marginal setae; when three, the lateral seta displaced very close and ventrally to basal seta (Figs. 18, 21, 22, 39). Apical scutellar setae crossed and horizontal. Anatergite bare or with small patch of short, black, erect setulae. Anterior and posterior lappets of metathoracic spiracle about equal in size (Fig. 24). Postmetacoxal area membranous. Wing (Figs. 6, 7, 16, 19, 25, 26, 30, 40): membrane varied from hyaline to strongly pigmented. Ventral calypter usually divergent from the scutellum (Figs. 18, 21). Costal spine not differentiated, usually shorter than costal setulae. Second costal portion (CS2) ventrally bare. R1 bare. Base of R4+5 dorsally bare or with few setulae basally. CuA1 bare. Bend of M with or without a stub or continuation. Cell r4+5 varied from just closed at wing margin to long petiolate. Legs: Medial anterior surface of fore coxa bare or predominantly so. Preapical anterodorsal seta on fore tibia at most as long as preapical dorsal seta. Mid tibia with 1–3 anterodorsal setae. Hind tibia with 2 or 3 dorsal preapical setae. Preapical posteroventral seta on hind tibia nearly as long as preapical anteroventral seta. Anterodorsal setae on hind tibia irregular in length. Posterior margin of hind coxa bare. Abdomen (Figs. 31, 41, 43): varied from black to yellow in ground colour, with or without microtrichia. Mid-dorsal depression on abdominal syntergite 1+2 confined to anterior 0.50–0.75 of segment. Marginal setae on tergites 3–5 “shifted” anteriorly into sub-discal position. Tergites 3 and 4 without median discal setae. Male terminalia (Figs. 9, 10, 27, 32–35, 44–47): Tergite 6 narrow, fused with segment 7+8. Epandrium short and convex. Hypandrial arms not joined, sub-parallel. Pregonite pointed distally and strongly bent anteriorly, posterior margin with setae. Postgonite varied from straight to sinuous, with or without setae. Basiphallus without basal keel. Epiphallus in para-basal position, well developed, usually weakly sclerotized. Basiphallus joined to distiphallus by dorsal sclerite. Dorsolateral lobes of distiphallus well developed and “shifted” anteriorly. Acrophallus not tubular. Cerci not fused distally. Surstylus distally bent posteriorly.
Hosts. Embioptera (so far known only for R. exquisitus and R. whiteheadi).
Distribution (Fig. 1). Palaearctic: East Mediterranean Europe (Tschorsnig et al. 2004), Iran (Herting 1983; Richter 2001), Iraq, Israel, Egypt (Sinai) (Kugler 1972; present work), Transcaucasia (Richter 1995), Turkmenistan (Ziegler 1991), Tunisia (Tschorsnig & Richter 1998; present work); Afrotropical: Namibia (present work), South Africa (Mesnil 1953; Crosskey 1980; Crosskey 1984).
Remarks on Mesnilomyia. The genus Mesnilomyia was described by Kugler (1972: 103) to include three new species: M. magnifica Kugler, 1972 from Israel and Iraq, M. achilleae Kugler, 1972 and M. longicornis Kugler, 1972 from Israel (Fig. 1). Of these, M. longicornis has since been recorded from Greece (including Crete and the North Aegean Islands), Bulgaria (cf. Herting 1984; Tschorsnig et al. 2004) and Transcaucasia (Richter 1995) (Fig. 1). Later Herting (1983: 5) described a fourth species, M. subaperta, based on a single male specimen collected in southeastern Iran (Anbar-Abad), which considerably differs morphologically from males of the previously described species (see below). Mesnilomyia subaperta was later recorded also from Turkmenistan by Ziegler (1991), this being the only other known record for the species. Recently Zeegers (2007) described M. calyptrata Zeegers, 2007 and M. rufipes Zeegers, 2007 from Yemen. The systematic position of Mesnilomyia was originally discussed by Kugler (1972) who concluded, after a brief morphological analysis: “According to Mesnil (personal communication), Mesnilomyia is close to the Ptilopsinina, but flies belonging to this subtribe have discal bristles at least on the fifth abdominal segment.” Mesnil (1972), following his communication to Kugler, included Mesnilomyia in the Ptilopsinina, together with the only other genus Ptilopsina Villeneuve, 1920: 117 [currently = Anthomyiopsis Townsend, 1916: 20]. Herting (1984) did not accept Mesnil’s conclusions and included Mesnilomyia in the Minthoini. Herting (1984: 191, note 100) emphasised that the presence of posterior extensions of the labella is “characteristic” for Minthoini, although Mesnilomyia spp. usually do not share this character state [except for the females of R. longicornis and R. whiteheadi]. The posterior extensions of the labella are also lacking in many other Minthoini (e.g. Actinochaeta Brauer and Bergenstamm, Actinominthella Townsend, Dolichopodomintho Townsend, Hyperaea Robineau-Desvoidy, Paradidyma Brauer and Bergenstamm).
A detailed examination of the external morphology of all species and of the male terminalia of most species did not reveal any apomorphies supporting Mesnilomyia as a monophyletic group. On the other hand, the morphology of the surstylus and phallus of Rossimyiops whiteheadi Mesnil indicates that the species so far ascribed to Mesnilomyia [except M. calyptrata, see below] form a paraphyletic group with respect to R. whiteheadi.
Remarks on Persedea. The genus Persedea was known only from the type species. Richter (2001: 26), in her diagnosis of the genus, underscored that Persedea can be clearly distinguished from Mesnilomyia by: i) sclerotized postmetacoxal area, as in Plesina Meigen, ii) small ventral calypter, not deflected as in Mesnilomyia, and iii) sternite 2 not hidden by the margins of the corresponding tergite. Re-examination of the holotype of Persedea exquisita did not reveal any sclerotization of the postmetacoxal area, whereas the shape and orientation of the ventral calypter varied greatly in all other species now assigned to Rossimyiops; thus, the use of the latter character is not advisable in a generic diagnosis. Similarly, the exposition of the sternites varied greatly according to specimen of Rossimyiops examined, probably because of the degree of sclerotization of the cuticle and the way in which the specimen had dried out. Characters or combinations of characters unequivocally identifying Persedea could not be found and this genus is therefore synonymised under Rossimyiops.
description: Published as part of Cerretti, Pierfilippo, Biase, Alessio De & Freidberg, Amnon, 2009, Systematic study of the genus Rossimyiops Mesnil (Diptera: Tachinidae), pp. 31-56 in Zootaxa 1984 on pages 32-34, DOI: 10.5281/zenodo.185371