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Anastrepha and Toxotrypana:
descriptions, illustrations, and interactive keys

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Allen L. Norrbom, Cheslavo A. Korytkowski, Roberto A. Zucchi, Keiko Uramoto, George L. Venable, Jerrett McCormick and Michael J. Dallwitz

Anastrepha steyskali Korytkowski

Morphology

Body. Setae dark brown to black.

Head. Frons without brown markings except ocellar tubercle. Occiput without brown marks. Frontal setae 3–5 (4, Korytkowski 1974). Orbital setae 2. Ocellar seta weak, small or absent. Gena without brown spot. Facial carina in profile concave or flat on dorsal 2/3. Face without brown markings. Antenna not extended to ventral margin of face.

Thorax. Mesonotum length 3–3.75 mm (3.2–3.5, Korytkowski 1974). Postpronotal, presutural supra-alar, dorsocentral, intra-alar and scutellar setae well developed, subequal to or longer than scutellum length. Acrostichal seta well developed. Basal scutellar seta strong, longer than scutellum. Mesonotum yellow, or orange. Scutum with 3 (both medial and sublateral) pale postsutural vittae; pale sublateral postsutural vitta extended posteriorly to intra-alar seta. Scutum posteriorly without brown or orange brown markings. Scutum without brown vittae. Scutellum entirely yellow or with dark markings only on extreme base of disk. Mesopleuron mostly yellow to orange, without brown markings. Subscutellum entirely yellow to orange. Mediotergite entirely yellow to orange.

Wings. Wing length 7.6–9 mm (8.3, Korytkowski 1974). Wing pattern typical Anastrepha pattern (S-band complete or at most interrupted at crossvein r-m, C-band and at least proximal arm of V-band present). C-band broadly extending to vein M in cell br along cell bm; covering base of cell r2+3; yellow or orange area posterior to pterostigma filling all of band in cells r1 and r2+3, or broad, extending distally into cells r1 and r2+3 at least to level of midlength of pterostigma. C-band and S-band separated (by hyaline band from cell bm to costal margin in cell r1). S-band extended anteriorly to vein R4+5 and covering all of crossvein r-m. Cell bm entirely hyaline or infuscated only along subapical fold. S-band base without extension in middle of cell cu1 to posterior wing margin; without extension in cell a1 to or almost to posterior margin. S-band middle section predominantly or entirely orange, often with brown margins. Subapical hyaline area in radial cells distal to r-m extending anteriorly into cell r1. S-band distal section without marginal hyaline band or spots in cell r2+3 or near apices of R2+3 or R4+5. S-band distally extended to apex of vein M. V-band proximal arm as dark as apical half of S-band; not connected anteriorly to S-band; not connected to S-band in cell dm. V-band distal arm absent. Vein R2+3 not sinuous; without accessory vein. Vein R4+5 distal to crossvein r-m more or less evenly curved or not strongly bowed medially. Crossvein dm-cu orientation with anterior end more distal than posterior end.

Abdomen. Abdominal tergite without brown markings. Lateral surstylus in posterior view short, somewhat boot-shaped, truncate and with apex slightly laterally projected. Surstylus in posterior view with lateral margin concave. Surstylus in posterior view with mesal margin convex, or straight. Glans present. Oviscape length 2.85–3.65 mm (3.25, Korytkowski 1974); spiracle ratio (distance from base to spiracle/oviscape length) 0.43, Korytkowski 1974. Eversible membrane with dorsobasal denticles all sclerotized, in continuous triangular to semicircular or suboval pattern. Eversible membrane with "as in rheediae, with very strong teeth, arranged in 5–6 rows and each with the base very enlarged", Korytkowski 1974. Aculeus length 2.2–2.8 mm (2.5, Korytkowski 1974). Aculeus length/oviscape length 0.77, Korytkowski 1974. Aculeus in lateral view dorsally curved (with sharp dorsal bend near midlength). Aculeus tip length 0.09–0.14 mm (0.11, Korytkowski 1974); tapered, then triangular, or parallel-sided, then triangular; not flared outward at or proximal to base; without ridges or lobes; without elongate dorsolateral depressions apically; with minute serration, visible only with compound microscope, or with fine serrations; serrated part 0.75–0.9 times length of tip (0.82, Korytkowski 1974). Aculeus tip with serrations separated by less than width of serration.

Miscellaneous

Data source: Korytkowski 1974. Sex of recorded specimens: male and female. Species group: leptozona group.

Biology and economic significance

This species is a potential pest of Chrysophyllum cainito L. (Sapotaceae), its only recorded host. Refer to the Fruit Fly Databases for host plant information.

Illustrations

• Wing (Korytkowski 1974, fig. 1). • Terminalia, male & female.

Links

Fruit Fly Databases for host plant, distribution, and nomenclatural information. Google search.