Oromasiphya Townsend, 1927

Toma, Ronaldo & Pinheiro, Rodrigo A., 2025, New species of Oromasiphya Townsend (Diptera: Tachinidae) with a key to the species, Zootaxa 5729 (1), pp. 163-174 : 164-168

Oromasiphya Townsend, 1927

( Figs. 1–31 )

Oromasiphya Townsend, 1927: 249 . Type species, Oromasiphya ornata Townsend, 1927: 249 , original designation. Townsend (1936) (key to Masiphyini genera); Townsend (1941) (diagnosis); Thompson, (1963) (comparison with Pseudomasiphya ); Guimarães (1966a) (new species); Guimarães (1966b) (biological observation); Guimarães (1971) (catalog); Guimarães (1977) (host-parasite catalog); O’Hara et al. (2020) (checklist).

Diagnosis. Oromasiphya species share with other members of Masiphyini the following combination of features: parafacial bare; lower facial margin visible in profile below the vibrissal angle; postpronotum with five setae, with middle basal seta positioned anteriorly, forming a triangle with inner and outer basal setae; three strong postsutural supra-alar setae, first postsutural supra-alar seta at least as long as first postsutural dorsocentral seta; aedeagus without epiphallus; distiphallus morphologically complex, membranous with minute structures similar to spines or feathers; pre- and postgonites fused, but slightly separated at the apex; segment 7 + 8 elongated in male. The Oromasiphya species is separated from the other species of Masiphyini by the combination of features: eye bare; palpus, costal seta, and ocellar seta developed; syntergite 1+2 and tergite 3 with a pair of median marginal setae; discal setae present on at least one of the intermediate segments; females have short claws; three katepisternal setae.

Redescription. Male. Head: eye bare; inner vertical setae well developed and subparallel; outer vertical setae slightly divergent and slim; ocellar setae well-developed and proclinate; five or six convergent frontal setae; upper portion of fronto-orbital plate usually with three or four reclinate orbital setae almost in line with row of frontal setae; the lowest frontal seta near level of lower margin of pedicel; fronto-orbital plate with a few sparse black hairs; parafacial bare; fronto-orbital plate wider than parafacial, the latter narrowing slightly toward gena; facial ridge with setulae on lower one-fourth.

Thorax. acrostichal setae 3 + 3, posteriormost presutural acrostichal seta near transverse suture; dorsocentral setae 3 + 3; intra-alar setae usually 2+3, anteriormost presutural intra-alar seta near postpronotal lobe, posteriormost presutural intra-alar seta close to transverse suture, and two or three extra setae flanking postpronotal lobe; supra-alar 1 + 3; three postalar setae, posteriormost shorter and setula-like; three katepisternal setae, the ventral one shorter and slightly forward; scutellum with a pair of basal, subapical, apical, and discal setae; subapical scutellar setae longer and slightly divergent, and apical scutellar setae crossed and about half of subapical setae length.

Wing. Costal seta developed; vein r4+5 setose between half and two-thirds of the way to the crossvein r-m; cell 4+5 open.

Legs. Tarsal claws longer than tarsomere 5; fore tibia with two posterior setae; mid tibia with two or three strong anterodorsal setae interspersed by smaller setae, two or three posterior setae interspersed by smaller setae, the proximal posterior seta shorter or absent, and one or two ventral setae; hind tibia with irregular row of short and long anterodorsal setae, two larger posterodorsal setae in the middle of a row of smaller setae, and three or four ventral setae on apical half.

Abdomen. Syntergite 1 + 2 with middorsal depression extending back to its hind margin, with one pair of median marginal, one pair of lateral marginal, and one pair of lateral discal setae; tergite 3 with one pair of median marginal, one pair of lateral marginal, usually one pair of discal, and one pair of lateral discal setae; tergite 4 with a row of marginal setae and a pair of discal setae; tergite 5 with one or two rows of discal setae (the proximal one more irregular) and a row of marginal setae; ventral side of tergite 5 with yellow patch of micro-hairs; ventral side of the tergites with long hairs, thickening from the base to the posterior margin of the tergites; with the exception of O. urbanae , ventral side of abdomen usually with marginal setulae on syntergite 1+2 and tergite 3 and discal setulae on tergite 3.

Terminalia ( Figs. 17–31 ) usually with tergite 6 short with a few setulae posteriorly, connected with segment 7 + 8 and tergite 5 by narrow intersegmental membranes; segment 7 + 8 elongated and longer than epandrium, with a group of setulae posteriorly, and with one spiracle on each side; anterior epandrial extension not developed and closely connected with segment 7 + 8; sternite 5 with convex anterior margin and V-shaped posterior margin with setulae; sternite 6 sub-symmetrical with long narrow arms, with a strongly sclerotized connection with the inner portion of sternite 5; connection of the sternite 6 with the segment 7+ 8 hinged on both sides, the connection of the right arm wider in ventral view; cercus in profile tapering from base to apex; cerci in posterior view fused medially; surstyli in profile tapering to apex, basal third less sclerotized; aedeagus relatively long; epiphallus absent; distiphallus with a complex membranous apical structure with micro-spines; pre- and postgonites fused, forming a relatively long flat plate with a hook-shaped apex.

Female. Differs from male in having wider vertex; stronger outer vertical setae; usually two reclinate orbital setae; two proclinate orbital setae; legs with similar chaetotaxy, but stronger than male; more ovate abdomen; tergites 4 and 5 without yellow patch of micro-hairs.

Comments. Thompson (1963) stated that his new species Pseudomasiphya petiolata is morphologically close to the Oromasiphya species, differing from the latter by the cell r 4+5 closed and short petiolate. He described the adult of this species based on two female specimens, whose terminalia pattern is also similar to that of Oromasiphya . It is quite possible that they are congeneric and that Pseudomasiphya will be synonymized with Oromasiphya when the male of P. petiolata is known.

The distiphallus apex in this genus is complex, as it is in species of Masiphyini whose male terminalia are known. However, some characteristics are consistently observed in most Oromasiphya species ( O. diamantina Toma & Pinheiro sp. nov., O. guimai Toma & Pinheiro sp. nov., O. mineira Toma & Pinheiro sp. nov., and O. ornata Townsend ). These include a dorsal tube with a flap-like structure at its dorsal base, and a pair of ventral tubes featuring sclerotized flaps at their bases. These features are notably absent in O. urbanae Guimarães , which suggests a potentially closer relationship among the first four species. On the other hand, understanding the homology of the distiphallus apex remains unclear when comparing this structure among the Masiphyini species illustrated by Thompson (1963) and Guimarães (1966a), due to significant differences in this structure among the various species.

Biology. The only known host information was reported by Guimarães (1966 a, b, 1977) for Oromasiphya urbanae in the nymph of Miobantia Giglio-Tos, 1917 (as Antimiopteryx Giglio-Tos, 1927 ) ( Thespidae ). He reported two host molts before and one after larval hatching.

Figures

FIGURES 1–8. Oromasiphya spp., male habitus, lateral and dorsal views (scale bar 1mm): 1 and 2, Oromasiphya diamantina sp. nov.; 3 and 4, Oromasiphya guimai sp. nov.; 5 and 6, Oromasiphya mineira sp. nov.; 7 and 8, Oromasiphya ornata Townsend.

FIGURES 9–16. Oromasiphya spp. 9 and 10, Oromasiphya urbanae Guimarães, male habitus, lateral and dorsal views (scale bar 1mm); 11 and 12, Oromasiphya urbanae and Oromasiphya mineira sp. nov., respectively: abdomen ventral view (scale bar 1 mm); 13 and14, Oromasiphya urbanae, female habitus, lateral and ventral views (scale bar 1 mm); 15 and 16, Oromasiphya diamantina sp. nov., female terminalia, lateral and ventral views (scale bar 0,25 mm). Abbreviations: cerc—cercus; hyprct— hypoproct; ps—piercing structure; st6—sternite 6; st7—sternite 7; tg6—tergite 6; tg7 tergite 7.

FIGURES 17–31. Oromasiphya spp., male terminalia, lateral, posterior, and ventro-lateral views (scale bar 0,25 mm): 17– 19, Oromasiphya diamantina sp. nov.; 20–22, Oromasiphya guimai sp. nov.; 23–25, Oromasiphya mineira sp. nov.; 26–28, Oromasiphya ornata Townsend; 29–31, Oromasiphya urbanae Guimarães. Abbreviations: cerc—cercus; distph—distiphallus; dlfp—flap-like structure at the dorsal base of the dorsal tube; dlt—dorsal tube; epand—epandrium; hypd—hypandrium; pret+pgt—fused pre- and postgonites; segm7+8—segment 7+8; st5—sternite 5; st6—sternite 6; sur—surstylus; vlfp—flap-like structure at the ventral base of the ventral tube; vlt—ventral tube.