Drosophila (Drosophila) asymmetrica, Vaz & Vilela & Carvalho, 2018

Drosophila (Drosophila) asymmetrica sp. nov. ( Figs. 5–33)

Drosophila sp. I 4, Vaz et al., 2014:608 ( Table 1 View Table 1 , feeding site), 609 ( Fig. 6, puparium [upper one]), 611 (Tables 3 and 4, breeding site), suppl. key S1 (feeding site, key), suppl. key S2 (breeding site, key).

Diagnosis. Medium-sized dull grayish yellow fly, body length (excluding wing) about 2.7 mm (male) and 3.0 mm (female); h index 1.1–1.8; mid katepisternal about 13–40% of the anterior one; abdomen dull, grayish yellow; tergites 2–5 with medially interrupted posterior darker bands; tergites 1 and 6 devoid of bands; wings uniformly slightly darkened; C index 2.0–3.0; larvae and pupae with very long conspicuous posterior and anterior horns, respectively; aedeagus distally asymmetric; conspicuous narrow oviscapt valve.

Material examined (10 males, 7 females; deposited in MZSP). Holotype male [wild-caught, coded M18, double-mounted, photomicrographed ( Figs. 5–7), right wing removed ( Fig. 11), dissected ( Figs. 12–26)] labeled: “ Brasil – SP – São Paulo, Reserva Florestal do Instituto de Biociências , 28.XII.2006, Vilela coll. / Drosophila asymmetrica [male symbol], Vaz, Vilela & Carvalho/fotomicrografado [photomicrographed]/terminália ilustrada [illustrated terminalia]/HOLOTYPE/[microvial with terminalia and right wing in glycerin]” . Seven paratypes (5 ♂♂, 2 ♀♀), same data as holotype , plus 9 paratypes (4 ♂♂ [one photomicrographed ( Figs. 5–7)], 5 ♀♀ [one photomicrographed ( Figs. 8–10), one dissected ( Figs. 27–33)]), same data as holotype except collection date (18, 22, 26.XII.2006) .

Type locality. Forest Reserve of the Instituto de Biociências da Universidade de São Paulo (IB-USP) (23 ◦ 33.96 Ɩ S; 46 ◦ 43.72 Ɩ W), Cidade Universitária “ Armando de Salles Oliveira ”, São Paulo city, state of São Paulo, Brazil.

Description. Male (n = 10). Head and frons dull grayish yellow, frontal length 0.37 mm (0.34–0.39) mm; frontal index = 1.12 (1.00–1.23), top to bottom width ratio = 1.56 (1.46–1.69). Frontal triangle light gray pollinose, about 100% of frontal length; ocellar triangle shiny light brown, 31–43% of frontal length. Or3 to or1 = 67–83% of that to inner vertical; or1/or3 ratio = 0.95 (0.78–1.22); or2/or1 ratio = 0.50 (0.36–0.71); poc 50–60%, oc 56–73% of frontal length; vibrissal index = 0.14–0.40, vt index = 1.12 (1.00–1.33), facial carina light brown, nose-like, slightly sulcate. Gena light brown, cheek index about 5.50–8.00. Eye dark red. Eye index = 1.10–1.40. Pedicel brown, laterally lighter, first flagellomere light brown, length to width ratio 1.20–2.00. Arista with 3 dorsal, 1–2 ventral and 3–4 tiny inner branches, plus terminal fork. Proboscis brown.

Thorax dull grayish yellow; length 1.11 (1.00–1.22) mm. Scutum pollinose, brownish-gray, 8 rows of acrostichal setae. h index = 1.32 (1.11–1.80). Transverse distance of dorsocentral setae 251% of longitudinal distance; dc index = 0.66 (0.58–0.72).Scutellum pollinose, laterally light brown, medially darker; distance between apical scutellar setae about 71% of that of apical to basal one, basal setae convergent; apical setae cruciate, scut index = 0.81 (0.68–0.89).Halter gray. Pleura brownish gray, sterno index = 0.78 (0.59–0.88), mid katepisternal seta about 13–40% of the anterior one. Legs brownish gray.

Wing ( Fig. 11) uniformly slightly darkened; length 2.06 (1.78–2.67) mm, length to width ratio = 2.06 (1.93–2.21). Indices: C = 2.60 (1.95–2.84), ac = 2.46 (2.11–2.71), hb = 0.49 (0.40–0.63), 4C = 0.90 (0.79–1.16), 4v = 1.69 (1.50–1.91), 5x = 1.75 (1.67–1.86), M = 0.54 (0.46–0.58), prox. x = 0.59 (0.52–0.68).

Abdomen ( Figs. 5–7) dull grayish yellow; tergites 2–5 with medially interrupted posterior darker bands; tergites 1 and 6 devoid of bands. Male Terminalia ( Figs. 12–26). Epandrium microtrichose on posterior median and dorsal areas; ca. 2 upper and 12 lower setae; ventral lobe weakly sclerotized, slightly covering surstylus, devoid of microtrichiae, posterior margin noticeably concave. Cerci mediodorsally microtrichose, widely fused to epandrium. Surstylus bearing a small patch of microtrichiae on mediodorsal area, with ca. 7 cone-shaped prensisetae, ca. 4 long, strong outer setae and ca. 11 long, thin, mostly inner setae. Decasternum as in Figs. 13, 14, 23; anteriorly turned dorsalwards, anteromedial tip area slightly sclerotized (not seen in Figs. 13, 23), sharply carinate on posterior mediodorsal half ( Fig. 14). Hypandrium ( Figs. 15–17) shorter than epandrium, anterior margin convex; dorsal arch and posterior hypandrial process absent; gonopod bare, linked to paraphysis by membranous tissue ( Fig. 17). Aedeagus ( Figs. 18–22) medially and distally asymmetric, anteriorly bearing a pair of tiny, acute spines pointed basalwards, subdistally bearing pair of dorsal, small, triangle-shaped spines ( Fig. 18); right side medially and distally pleated leftwards over most dorsal cleft, partially covering left side, hiding left subdistal spine. Aedeagus in dorsal ( Fig. 18) and ventral ( Fig. 22) views depicting only the right subdistal spine on the left side; apically blunt in lateral view ( Fig. 20). Aedeagal apodeme, rod-shaped, curved, laterally flattened, slightly shorter than aedeagus. Ventral rod completely fused to aedeagal apodeme, distally expanded laterally, relatively long ( Fig. 20). Paraphysis right-angled triangle-shaped in lateral view ( Fig. 16), bearing a small setula at very distal tip. Ejaculatory apodeme as long as aedeagal apodeme, dorsodistally expanded laterally and crescent-shaped ( Figs. 24, 25), laterally L-shaped and proximally expanded dorsoventrally ( Fig. 26).

Female (n = 7). Head and frons dull gray, frontal length 0.40 mm (0.37–0.41) mm; frontal index = 1.12 (1.00–1.21), top to bottom width ratio = 1.65 (1.47–1.79). Frontal triangle light gray pollinose, about 100% of frontal length; ocellar triangle shiny light brown, 35–40% of frontal length. Or3 to or1 = 67–100% of that to inner vertical; or1/or3 ratio = 0.88 (0.82–0.91); or2/or1 ratio = 0.53 (0.44–0.60); poc 53–67%, oc 71–81% of frontal length; vibrissal index = 0.21–0.42; vt index = 1.07 (1.00–1.18); facial carina light brown, nose-like, slightly sulcate. Gena light brown, cheek index about 5.75–8.33. Eye dark red. Eye index = 1.14–1.42. Pedicel brown, laterally lighter, first flagellomere light brown, length to width ratio 1.40–2.00. Arista with 3 dorsal, 2 ventral and 2–5 tiny inner branches, plus terminal fork. Proboscis brown.

Thorax dull grayish yellow; length 1.27 (1.20–1.39) mm.Scutum pollinose, brownish-gray, 8 rows of acrostichal setae. h index = 1.27 (1.11–1.50). Transverse distance of dorsocentral setae 242% of longitudinal distance; dc index = 0.66 (0.58–0.74). Scutellum pollinose, laterally light brown, medially darker; distance between apical scutellar setae about 78% of that of apical to basal one, basal setae convergent; apical setae cruciate, scut index = 0.85 (0.81–0.90). Halter grayish yellow. Pleura grayish yellow, sterno index = 0.80 (0.74–0.83), mid katepisternal seta about 21–33% of the anterior one. Legs dull grayish yellow.

Wing uniformly slightly darkened; length 2.34 (2.20–2.54) mm, length to width ratio = 2.08 (2.02–2.14). Indices: C = 2.70 (2.42–2.95), ac = 2.42 (2.20–2.67), hb = 0.53 (0.40–0.64), 4C = 0.89 (0.79–1.00), 4v = 1.66 (1.52–1.96), 5x = 1.51 (1.33–1.75), M = 0.52 (0.44–0.61), prox. x = 0.58 (0.52–0.63).

Female terminalia ( Figs. 27–33). Tergite 8 narrow, devoid of setae ( Fig. 27), anterodorsally microtrichose, mediodistally weakly sclerotized ( Fig. 28); ventral half curved frontwards, distally bearing a row of ca. 8 thin, long setulae adjacent to posterior margin ( Figs. 27–30); epiproct mostly microtrichose, setose, anterolaterally embraced by basal area of larger hypoproct ( Fig.29); hypoproct mostly microtrichose, setose, conspicuously bearing two pairs of stronger and longer setae ( Fig. 27). Valve of oviscapt relatively narrow, distally rounded, subdistally slightly expanded dorsoventrally and ventrally slightly sinuate in lateral view ( Figs. 31, 33), bearing ca. 5 discal and about 20 marginal, peg-like, mostly roundish-tipped, outer ovisensilla ( Fig. 33); trichoid-like inner ovisensilla: 3 thin distally positioned, and 1 long, slightly curved, subterminal ( Fig. 33). Spermathecal inner capsule cylinder-shaped, sclerotized, enlarged at base, distally flattened; basal introvert deeply invaginated ( Fig. 32).

Puparium.One puparium of Drosophila asymmetrica , sp.nov. collected from an inflorescence of G. cylindrica , in Rio de Janeiro city was photomicrographed ( Fig. 6 [upper one] of Vaz et al., 2014 [cited the figure caption as Drosophila sp. I 4]; host plant unintentionally omitted) together with one puparium of Drosophila calatheae [lower one], obtained from the from the same host plant. Puparia of both species conspicuously bear long horns and a wide air-filled space on their anterior end, probably related to floatation inside bracts phytotelmata.

Ecology. Breeds on inflorescences of Goeppertia monophylla ( Table 1 View Table 1 ).

Etymology. Named to indicate its conspicuously asymmetric aedeagus.

Note. A remarkably similar oviscapt valve and similar spermathecae were depicted and photomicrographed by Vilela & Bächli (1990:215, Fig.58 E Fig. 58; 323, Fig.166B) for the noticeably smaller female paralectotype of Drosophila boliviana Duda, 1927 , collected from “Yungas von Coroico”, Bolivia. The cited authors considered the two female paralectotypes of the type series of D. boliviana as belonging to distinct species. As we suspect the smaller female paralectotype of Drosophila boliviana and Drosophila asymmetrica could be conspecific, the eventual capture and identification of a similar male from “Yungas von Coroico” would be desirable to confirm our suspicion.