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Anastrepha bicolor (Stone)

Recognition
Anastrepha bicolor belongs to the daciformis species group, which differs from other species of Anastrepha in having the basal third of the scutellum brown, the male phallus extremely short (less than 0.30 mm long) and with the glans absent (as in the dentata group), and the female eversible membrane dorsobasally with a single, medially interrupted row of very stout scales.  Anastrepha bicolor is one of several species with a vespidlike wing pattern comprising only a broad, uninterrupted, costal band covering all of cell r₂₊₃, and a cubital streak.  It differs from A. macrura and A. zucchii in having the presutural lateral stripe complete. It differs from A. aquila, A. avispa and A. zucchii in having the posterior half of the part of cell br bordering bm hyaline and bare of microtrichia. Its banded abdominal pattern clearly distinguishes A. bicolor from A. macrura and A. zucchii, in which the abdomen is brown with a pale stripe or T-shaped mark, and less so from A. aquila and A. avispa, which are intermediate in abdominal pattern.

Description
Body predominantly dark orange-brown to dark brown.

Head: Mostly yellow. Frons with brown transverse dorsal band, usually more or less rectangular, narrow to moderately broad, orbital seta at margin or anterior to band. Gena with large brown spot below eye. Occiput entirely yellow. Posterior orbital seta usually absent (of 38 specimens examined by Norrbom 1998 with intact head setae, absent except in 1 male from Morelos, and on one side only on 1 female from Sinaloa).

Thorax: Medial pale stripe bilobed posteriorly, lobes moderately slender, often with distinct anterolateral corner, usually extended to dorsocentral seta. Presutural dorsocentral pale stripe connected anteriorly to pale area on postpronotal lobe and connected or narrowly separated from pale sublateral stripe. Presutural lateral pale stripe well differentiated, complete, including posterior part of notopleuron. Pleuron brown except following yellow areas: all of propleuron; anteroventral corner and posterodorsal half of anepisternum; dorsal band or 2 spots on katepisternum; katepimeron; anterior 1/4 of meron; anterior 2/3 of katatergite; and most of anatergite. Subscutellum and mediotergite entirely brown, or mediotergite occasionally dark orange medially. Scutum without microtrichia except on anterior part of sublateral stripe, lateral to sublateral stripe and posterior to dorsocentral seta; notopleuron usually partly microtrichose; scutellum microtrichose except basal area on side.

Wing: C- and S-bands completely fused along costa to form broad, uninterrupted, orange to dark orange-brown marginal band; in cell br at most covering anterior half of section bordering cell bm, not extended to vein M; covering all of cells r₁ and r₂₊₃ and anterior margin of cell r₄₊₅; well separated from apex of vein M. S-band incomplete, middle part between veins R₄₊₅ and Cu₁ absent; basal part paler than C-band; extended over base of cell cu₁ and faintly and diffusely along vein Cu₁ up to halfway to dm-cu, sometimes extended into cell dm towards r-m. V-band pale and diffuse; extended anteriorly only slightly into cell r₄₊₅; distal arm absent. Vein M strongly curved apically; M ratio 1.57-2.33. Cell br about half microtrichose (some Texas specimens) to mostly bare, section bordering cell bm with at least posterior half bare. Cell bcu with anterior margin and medial crease microtrichose, always with large bare areas anterior and posterior to crease, posteroapical lobe bare to entirely microtrichose.

Wing.

Abdomen: Tergites banded; base of syntergite 1+2 yellow; it and tergites 3-5 with posteromedial yellow areas broad, and, except often on tergite 5, with brown areas undivided medially; tergites usually without lateral yellow margins, but present in some Mexican and all Central American specimens.

Female terminalia: Oviscape length 3.58-6.45 mm, 1.17-1.86 times as long as mesonotum. Eversible membrane, on expanded basal part, with most dorsal scales weakly sclerotized, but with one, medially interrupted row of large, strongly sclerotized, hooklike scales. Aculeus slender, no more than 0.05 mm wide, except at base, length 3.22-5.57 mm; tip needlelike, nearly circular in cross-section, nonserrate, length 0.15-0.21 mm, width 0.04-0.05 mm.

Male terminalia: Lateral surstylus very short, barely extended beyond prensisetae. Phallus extremely short, less than 0.30 mm long; glans absent.