Drosophila sturtevanti, Duda, 1927

Roman, Bruna Emilia & Madi-Ravazzi, Lilian, 2021, Male terminalia morphology of sixteen species of the Drosophila saltans group Sturtevant (Diptera, Drosophilidae), Zootaxa 5061 (3), pp. 523-544 : 532

sturtevanti subgroup

( Figs. 8–11 )

General description of male terminalia. The characteristics of epandrium, cercus, surstylus, hypandrium and phallapodeme among the species in this subgroup are extremely similar. In the periphallic structures, the epandrium exhibits a pair of processes that extend from the lower ventral border, and are positioned parallel to the aedeagus, named epandrial ventral process. The dorso-ventral region of the epandrium is angular and it is covered with short and long epandrial bristles. The cercus is U-shaped and it is covered with cercal bristles. The surstyli are large and concave. Each surstylus has 13 to 18 surstylar teeth arranged only on the margins of the internal portion and presents a tuft of surstylar long bristles. The hypandrium is small and wide; it displays a pair of small hypandrial bristles on the median gonocoxites. The phallapodeme is short. The aedeagal sheath is absent. The aedeagi of species of this subgroup are the smallest of the saltans group, about 1/20 of the male’s body length. The phallic structures have a pair of pregonites, short, not fused, with a pair of small bristles in each pregonite, only a postgonite (ventral postgonite) and an aedeagal apex with punctate projection. The ventral postgonite does not appear to be flexible in these species. Each species has a particularity in aedeagus that differs from the other species.

Figures

FIGURE 8. Scanning electron micrographs of D. sturtevanti. male terminalia (A) Ventral and dorsal view of terminalia (630 x magnification). (B) Lateral view of aedeagus (1.490 x magnification). Arrow heads = “caudal” projection. Image from Madi- Ravazzi et al. (2021). (C) Dorsal view of aedeagus and middle ventral region of epandrium (1.470 x magnification). The imagens are from STV-1 (A, C) and STV-3 (B) strains. Abbreviations in Table 1.

FIGURE 9. Scanning electron micrographs of D. lehrmanae male terminalia. (A) Ventral and dorsal view of terminalia (526 x magnification). (B) Lateral view of aedeagus and phallapodeme (1.020 x magnification). Arrow heads = “caudal” projection. Image from Madi-Ravazzi et al. (2021). (C) Dorsal view of aedeagus (2.260 x magnification). The imagens are from STV-like strain. Abbreviations in Table 1.

FIGURE 10. Scanning electron micrographs of D. dacunhai male terminalia. (A) Dorsal view of terminalia (680 x magnification). (B) Dorsal view of aedeagus and middle ventral region of epandrium (1.570 x magnification). (C) Lateral view of aedeagus. Arrow heads = a groove in upper portion of ventral postgonite (1.680 x magnification). Image from Madi-Ravazzi et al. (2021). The imagens are from DAC strain. Abbreviations in Table 1.

FIGURE 11. Scanning electron micrographs of D. milleri male terminalia. (A) Ventral and dorsal view of terminalia (673 X magnification). (B) Lateral view of aedeagus (1.230 X magnification). Image from Madi-Ravazzi et al. (2021). (C) Dorsal view of aedeagus and middle ventral region of epandrium. Arrow heads = a groove in upper portion of ventral postgonite (1.210 X magnification). The imagens are from MI-2 strain. Abbreviations in Table 1.