Oxysarcodexia angulosa, Souza & Pape & Thyssen, 2020

Souza, Carina Mara De, Pape, Thomas & Thyssen, Patricia Jacqueline, 2020, Oxysarcodexia Townsend, 1917 (Diptera: Sarcophagidae) - a centennial conspectus, Zootaxa 4841 (1), pp. 1-126 : 23-24

Oxysarcodexia angulosa sp. n.

( Figs 25–28 )

urn:lsid:zoobank.org:act:9A065A1D-8BA5-4746-8EB4-F33182636D9B

Diagnosis. Postocular plate with golden pollinosity. Ocellar bristles equal in size to uppermost frontal bristles. Thorax Grayish with pale golden pollinosity. Four post-sutural dorsocentral bristles posteriorly; apical scutellar bristles absent. Legs blackish brown. Abdomen silvery pollinosity more intense laterally. T3 with 2 pairs of lateral marginal bristles, T4 with 3 pairs of lateral marginal bristles. ST5 with deep median V-shaped cleft. Cercus slightly sinuous in lateral view, with a blackish preapical expansion, pointed apex and small subapical bulge. Pregonite broad and with narrower, rounded apex; unicolorous. Postgonite slender and slightly curved, especially at apex; unicolorous. Phallic tube short. Distiphallus with bifurcated juxta and small spines along inner margins except at apex. Vesica well sclerotized, well developed, with angular ventroapical projection, enlarged base and bifurcated apex with small spines and horseshoe-like branches in anterior view; vesica forming an inverted L in lateral view and without any particular ornamentation.

Description. Male. Length 9.5–10.0 mm.

Head. Fronto-orbital, parafacial and postocular plates with golden pollinosity; occiput blackish with silvery pollinosity, black bristles in dorsomedial and lateral areas and golden bristles in ventromedial area; frons 0.1x head width at level of ocellar triangle; frontal vitta dark, slightly brownish anteriorly, with row of 7–9 frontal bristles; inner vertical bristle well developed, outer vertical bristle not differentiated; ocellar bristles equal in size to uppermost frontals; 2 reclinate fronto-orbital bristles equal in size to frontals; proclinate bristles absent; gena and postgena black, respectively with golden and silvery pollinosity and both with black bristles; antenna dark brown, first flagellomere with brownish pollinosity and 2.3x as long as pedicel; arista dark brown with middle portion lighter and long plumose on proximal 3/4; palpus dark brown.

Thorax. Grayish with pale golden pollinosity. Chaetotaxy: acrostichals 0+1, dorsocentrals 2+4, intra-alars 2+2, supra-alars 3+3, postalars 2, postpronotals 3, notopleurals 4 (2 large primaries and 2 smaller subprimaries), katepisternals 3 with middle one weaker and inserted slightly below others, meropleurals 10, postalar wall setose, scutellum with 1 discal, 1 lateral, 1 subapical and 0 apical bristles; prosternum setose at margins. Wing. Hyaline, tegula black, vein R 1 bare, vein R 4+5 setulose over 1/3 of distance to crossvein r-m, costal spine not differentiated, third costal sector without ventral setulae. Legs. Blackish brown, fore femur with rows of bristles on dorsal, posterodorsal, and posteroventral surfaces; fore tibia with 2 anterodorsal, 1 posterior and 1 posteroventral bristles; mid femur with 5 median anterior and 3 pre-apical posterior bristles, a ctenidium of flattened spines on distal posteroventral surface and posteroventral and anteroventral rows of long bristles; mid tibia with 1 anterior, 2 posteroventral and 1 posterodorsal bristles; hind femur with 1 strong anteroventral, 1 pre-apical posterior bristle and posteroventral and anterodorsal rows of long bristles; hind tibia with an anterior row of long bristles, 2 anteroventral, 1 dorsal, 3 posterodorsal and 2 posterior bristles; tarsi with ventral golden pollinosity (weaker on mid tarsus).

Abdomen. Blackish gray with silvery pollinosity, more intense laterally. T3 with 2 pairs of lateral marginal bristles, T4 with 3 pairs of lateral marginal bristles, T5 with 18 strong marginal bristles. ST2–4 square with a pair of strong bristles on posterior margin, ST5 with deep median V-shaped cleft ( Fig. 28 ). Terminalia . Syntergosternite 7+8 large, brownish with golden pollinosity laterally, scattered short black setulae and 12 marginal bristles; epandrium yellowish with short black setulae and golden pollinosity; surstylus oblong with narrow base and apex, enlarged in proximal two thirds, with sparse marginal and discal setulae and a long and slender light-yellow bristle at apex. Cercus slightly sinuous in lateral view, with a blackish preapical expansion, pointed apex and small subapical bulge. Pregonite with broad base and narrower, rounded apex; unicolorous. Postgonite slender and slightly curved, especially at apex; unicolorous. Phallic tube short. Distiphallus with bifurcated juxta and small spines along inner margins except at apex; lateral and median styli tubular and partially hidden by juxta. Vesica well sclerotized, well developed, with angular ventroapical projection 1.2x as long as apex of distiphallus, enlarged base and bifurcated apex with small spines and horseshoe-like branches in anterior view; vesica forming an inverted L in lateral view and without any particular ornamentation.

Female. See Remarks.

Etymology. From the Latin angulosus = full of corners. The specific epithet is an adjective pointing to the angled ventroapical projection of the vesica.

Remarks. The cercus of O. angulosa sp. n. is similar to that of O. perneta ( Walker, 1861) . However, other structures of the terminalia of O. angulosa sp. n., such as the short phallic tube and the vesica, are very peculiar and not seen in any other species of the genus. A female labelled “ COSTA RICA, San José; Cerro Muerte, 16km S; Empalme, 2600m; III–VI 1990 Hanson / COSTA RICA INBIO; CRI001; 107347” [INBio] most likely belongs to this species because of the blackish occiput with silvery pollinosity, head with black bristles in dorsomedial and lateral areas and sparse golden bristles in ventromedial area (even more sparse than in the male), and the light pale grayish thorax with golden pollinosity, blackish gray abdomen with silvery pollinosity, and yellowish terminalia with golden pollinosity, all of which are very similar to corresponding male features. Nevertheless, without a more exhaustive study of females analyzing their comparative morphology, we prefer to exclude this specimen from the type series.

Distribution. NEOTROPICAL. Costa Rica.

Biology. Unknown.

Type material. Holotype ♂: COSTA RICA: Punt. Monteverde 1840m; Cerro Amigos ; 14.VI.2000, T. Pape / INB0003086811 [INBio] // paratype ♂: Est. Cuerici. Send. El Carbon, 4.6km al E. de Villa Mills, Prov. San Jose, COSTA RICA 2600m. 26–31 OCT / 1995. B. Gamboa, L_S_389550_ / 500050 #6326 / COSTA RICA INBIO; CRI002; 363463 [INBio] // paratype ♂: Estac. Pitier, Prov. Punta., COSTA RICA. 1679m. 5–18 ENE 1995. G. Fonseca, L_N_330900_577400 #5950 [ NHMD].

Figures

FIGURES 25–32. Oxysarcodexia spp., males. 25–28. Oxysarcodexia angulosa sp. n., holotype (Costa Rica, Puntarenas, Monteverde, INBio). 25. Habitus, lateral view. 26. Terminalia, lateral view. 27. Terminalia, posterior view. 28. Terminalia, ventroapical view. 29–32. Oxysarcodexia ariozanoi sp. n., holotype (Brazil, Rio de Janeiro, Rio de Janeiro, MNRJ). 29. Habitus, lateral view. 30. Terminalia, lateral view. 31. Terminalia, posterior view. 32. Terminalia, ventroapical view.