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Toxotrypana curvicauda Gerstaecker

Recognition
This species, like other Toxotrypana species, is wasplike in appearance. The body is elongate, yellow with dark brown markings, the abdomen is petiolate, and the wing pattern includes only a broad costal band extending the length of the wing and a faint streak on the cubital cells. Toxotrypana species differ from other Tephritidae in having a medial, longitudinal depression on the scutum, vein R₂₊₃ with 3 sharp bends, often with spur veins arising from them, and most head and thoracic setae reduced in size. T. curvicauda is the only species of Toxotrypana known from the United States and the West Indies (it also occurs in Mexico, Central and northern South America). It is one of the species of this genus in which the female oviscape is extremely long (at least as long as the thorax and abdomen combined) and strongly arched.

Toxotrypana curvicauda differs from the other species of the genus with such long terminalia in the pattern of its dark brown thoracic markings. In particular, on the scutum the posterior brown mark is broader than long and separate from the submedial and sublateral stripes, and the latter are strongly laterally curved posteriorly. The anatergite at most has a dorsal and a ventrolateral spot (as opposed to a complete stripe or being mostly brown), and the scutellum at most has the base and lateral third of the apical margin brown.

The larvae are difficult to distinguish from those of other fruit flies. They are opaque whitish or yellowish, cylindrical, tapering anteriorly, with 13-15 oral ridges, 22-28 tubules on the anterior spiracle, relatively short posterior spiracular hairs, and with inconspicuous tubercles on the caudal segment (Heppner 1986).

Description
Adults wasplike in appearance, mostly yellow brown to orange with dark brown markings. Body 8-14 mm long, up to 25 mm. in female including ovipositor.

Lateral female habitus and dorsal male habitus (from Knab & Yothers 1914).
Click here for a female dorsal habitus image from Weems (1969) on the University of Florida site.

Head: Frons with frontal, orbital, and ocellar setae weak, sometimes absent. Vertex with dark brown band. Face often with dark band on ventral margin, less commonly with medial stripe on carina (often in Bahamas and Florida specimens lower part of carina broadly but diffusely dark); antennal groove entirely orange.

Thorax in dorsal, lateral, and posterior views. Click here for details.

Thorax: Predominantly yellow or orange. Scutum with dark brown submedial stripe ending approximately midway between transverse and scuto-scutellar sutures, not connected to posterior dark brown mark which is broader than long. Sublateral postsutural dark brown stripe distinctly laterally curved posteriorly, not connected to posterior dark mark. Lateral postsutural dark brown stripe absent (except in some Antillean specimens where present posterior to supra-alar seta and fused posteriorly with sublateral stripe). Dark brown presutural lateral spot usually large, at least its lateral margin uninterrupted, connected posteriorly to, but usually separated anteriorly from, dark brown notopleural mark which is usually uninterrupted medially. Scutellum orange, only base brown (rarely with margin dark on basolateral third). Anepisternum with 1 dark brown band, oblique or almost vertical from anterodorsal corner. Anepimeron with 1 dark brown vertical band. Anatergite at most with dark brown spot in ventrolateral corner and rarely (some Bahamas and  Florida specimens) also with dorsal spot. Subscutellum mostly dark brown, often with small medial yellow area. Mediotergite dark brown along lateral margins, sometimes with narrow medial stripe, rarely entirely dark brown. Postpronotal, presutural supra-alar, and anepisternal setae weak or absent, katepisternal seta absent. Dorsocentral seta usually weakly present. Acrostichal seta usually absent (weakly present in some specimens from Florida, Greater Antilles, and Trinidad). Basal scutellar seta absent.

Wing: As for genus. Wing pattern comprising only a broad, uninterrupted, brown costal band extending to apex (covering all of cells bc, c, sc, r1 and r₂₊₃ and anterior parts of cells br and r₄₊₅) and a faint streak over cell bcu. Vein R₂₊₃ with 3 sharp bends, often with spur veins arising from them. Cell bcu with posteroapical lobe relatively long. In male, costal setulae usually stout.

Abdomen: Petiolate, syntergite 1+2 narrowed. With following color pattern usually at least faintly visible, often dark brown and strongly contrasting: syntergite 1+2, tergites 3 and 4, and female tergite 5 with broad medial brown bands; male tergite 5 with large medial brown spot.

Male terminalia. Epandrium, surstyli and proctiger, lateral view, epandrium and surstyli, posterior view (setae omitted), and glans (from Norrbom 1985, fig. 15A-C).

Male abdomen: Terminalia with lateral surstylus short, rounded apically in posterior view. Phallus extremely long, longer than length of body; glans weakly sclerotized medially and with T-shaped subapical lobe.

Scanning electron micrographs of dorsobasal scales of eversible membrane and of aculeus tip, ventral view (from Norrbom 1985, fig. 14A, D).

Female abdomen: Oviscape extremely long, at least as long as the thorax and abdomen combined, and strongly arched. Everisble membrane dorsobasally with numerous large, hooklike spines. Aculeus tip with minute serrations. 

Variation: The abdominal color pattern varies considerably, but seems to be consistent in some local areas. For example, in central Mexico the pattern is weakly differentiated and the abdomen often appears entirely orange (Baker et al. 1944). Most specimens from Texas, northern Mexico, Central America, and Panama that have been examined have a distinct abdominal pattern, although some (e.g., from La Ceiba, Honduras and Santa Tecla, El Salvador) are mostly orange. The abdomens of specimens from Florida and the West Indies, including Trinidad, are variable and are often intermediate in color.

Certain dark markings are generally more extensive in the specimens from Florida, and especially St. John (the lectotype of curvicauda), Puerto Rico, the Dominican Republic, and the Bahamas. This is true to a lesser extent for specimens from Cuba, but not those from Trinidad. Often the anepisternal and anepimeral bands are broader, the dark area on the katepisternum is larger, the presutural lateral dark spot is connected to the notopleural mark both anteriorly and posteriorly, or the mediotergite is entirely dark. Acrostichal setae also are more commonly present in specimens from the eastern part of the range.

The costal setae in males from Cuba, Puerto Rico, and the Dominican Republic are less stout than in most other males seen, but the size of these setae varies considerably in males from Mexico (Baker et al. 1944) and Florida.

Immature Stages: Larvae up to 15 mm long, opaque whitish or yellowish, cylindrical, tapering anteriorly. Head with 13-15 oral ridges. Anterior spiracle fan-shaped, with 22-28 tubules. Posterior spiracle with openings elongate, 4-5 times as long as wide; hairs short, not much longer than width of spiracular openings. Caudal segment with tubercles and papillae inconspicuous (Heppner 1986, White & Elson-Harris 1992).