Drosophila zamorana, Penafiel-Vinueza, Ana Danitza & Rafael, Violeta, 2018

Penafiel-Vinueza, Ana Danitza & Rafael, Violeta, 2018, Five new species of Drosophilaguarani group from the Andes of southern Ecuador (Diptera, Drosophilidae), ZooKeys 781, pp. 141-163 : 141

Drosophila zamorana sp. n. Figs 1 A–D, 2 A–F, 3 A–C

Type material.

Holotype. ♂ (dissected, terminalia in microvial), Ecuador, Zamora Chinchipe, San Francisco, 2190 m, 3°59'16.7"S; 79°5'35"W, IV.2015, Apr. 2015, A. Peñafiel col., A. Peñafiel & V. Rafael det. (QCAZ-I 3266). Allotype ♀ (dissected, terminalia in microvial), Ecuador, Zamora Chinchipe, San Francisco, 2190 m, 3°59'16.7"S; 79°5'35"W, Apr.2015, A. Peñafiel col., A. Peñafiel & V. Rafael det. (QCAZ-I 3267).

Paratypes.

9 ♂♂ and 9 ♀♀ (dissected, terminalia in microvial, descendants of isofemale line), Ecuador, Zamora Chinchipe, San Francisco, 2190 m, same data as holotype, A. Peñafiel col., A. Peñafiel & V. Rafael det. (QCAZ-I 3268-3285).

Diagnosis.

Aristae generally with five dorsal and three ventral branches, plus terminal fork. Two prominent equally long oral bristles. Thorax brown, with bristles arising from dark brown spots, scutellum brown with some irregular light spots. Wings beige, veins bM-Cu and dM-Cu strongly clouded tips of R2 + 3, R4 + 5 radial and M veins darkened. Abdomen dark brown, 1st tergite beige, 2 nd– 4th tergites of males with dorsal midline and white butterfly-shaped areas, followed by a white rounded area at the edge of each tergite; 5th and 6th tergites dark brown. Cerci not fused to epandrium. Hypandrium shield-shaped. Gonopod elongated, bearing one long bristle. Aedeagus voluminous with two ventral sheets covered in spines, dorsally with two membranous sheets covered with tiny spines studs. Paraphyses triangular, bearing two small bristles.

Description.

Male. Holotype external morphology: total length (body + wings) 3.08 mm, body length 2.50 mm. Body color dark brown (Figure 1A).

Head. Aristae with five dorsal and three ventral branches, plus terminal fork. Frons dark brown, frontal length 0.20 mm; frontal index = 0.73; top to bottom width ratio = 1.44. Medial vertical seta was closer to lateral vertical seta and slightly towards the outer edge of the orbital plate; distance of or3 to or1 = 0.08, distance of or3 to vtm = 0.09; or1-or3 ratio = 1.7, or2-or1 ratio = 0.23, distance of ocellar setae = 1 of frontal length, distance of postocellar setae = 0.64 of frontal length. vt index = 0.66. Ocellar triangle dark brown, 48% of frontal length, ocellus yellow; frontal triangle brown. Frontal vitta yellowish brown. Gena and postgena dark brown. Carina not sulcate. Cheek index = 7.5. Eyes wine red; eye index = 1.4. Two prominent equally long oral bristles; vibrissa index = 1.1.

Thorax. Brown, with bristles arising from dark brown spots, thorax length 0.80 mm, acrostichal hairs in six rows between the two anterior dorsocentral setae, h index = 0.81. Transverse distance of dorsocentral setae = 2.28, dc index = 0.87. Scutellum brown with some irregular white spots (Figure 1A), distance between apical scutellar seta = 1, scut index = 1.13; medial katepisternal seta one third of the previous, sterno index = 2.16. Legs light brown, coxae and femora dark brown, tibiae with two brown rings. Wings beige, alar length 2.10 mm, width 0.90 mm, veins bM-Cu and dM-Cu strongly clouded tips of R2+3, R4+5 radial and M veins darkened. First costal section apex black (Figure 1B). Indices: alar = 2.25; C = 3.61; ac = 2.29; hb = 0.53; 4c = 0.86; 4v = 2.08; 5x = 1.65; M = 0.73 and prox. x = 0.77.

Abdomen. Dark brown, 1st tergite beige, 2nd - 5th tergites of males with dorsal midline and white butterfly-shaped areas with posterior dark pigmentation which reaches the exterior margin, leaving a white rounded laterally area; 6th tergite dark brown (Figure 1C).

Male terminalia. Epandrium dorsally microtrichose with two lower and no upper bristles, four bristles on the ventral lobe. Cerci sclerotized and not fused to epandrium, with some microtrichose areas in the middle (Figure 2A). Surstylus triangular with a row of eight primary teeth, nine secondary pointed teeth on the right and eight on the left; nine marginal bristles on the right and ten on the left (Figure 2B). Hypandrium sclerotized in shield-shape. Gonopod elongated bearing one long bristle (Figure 2C).

Aedeagus. Sclerotized, voluminous with two ventral sheets covered in short spines, dorsally with two membranous sheets covered with tiny spines. Paraphyses triangular and slightly microtrichose, bearing two small bristles (Figure 2D-F).

Variation in paratypes (dry mounted specimens). Total length (body + wings) 2.95-3.12 mm, body length 2.35-2.6 mm. Head. Frontal length 0.24-0.34 mm, frontal index = 0.73-1.12, top to bottom width ratio = 1.5-2.04; distance of or3 to or1 = 0.07-0.1, distance of or3 to vtm = 0.9-0.11, or1-or3 ratio = 0.52-0.94, or2-or1 ratio = 0.18-0.42, distance of ocellar setae = 0.5-1.04 of frontal length, distance of postocellar setae = 0.46-0.7 of frontal length, vt index = 0.96-1.21; cheek index = 7.0-9.8; vibrissa index = 0.92-1.12; eye index = 1.15-1.68. Thorax. Length 0.64-0.77 mm, h index = 0.85-1.04. Transverse distance of dorsocentral setae = 1.68-2.46, dc index = 0.69-0.70. Distance between apical scutellar seta = 0.94-1.05. scut index = 0.87-1.13; sterno index = 0.94-2.87.

Female. Allotype and paratypes (isofemale descendants). Allotype: total length (body + wings) 3.24 mm, body length 2.43 mm. Body color dark brown (Figure 3A).

External morphology. Same as the male except abdomen. Abdomen 1st tergite beige, 2nd - 6th tergites with dorsal midline and white butterfly-shaped areas with posterior dark pigmentation which reaches the exterior margin, leaving a white rounded lateral area (Figure 1D). Wings beige, alar length 2.54 mm, width 1.07 mm, veins bM-Cu and dM-Cu strongly clouded tips of R2+3, R4+5 radial and M veins darkened. First costal section apex black. Indices: alar = 2.37; C = 4.04; ac = 2; hb = 0.42; 4c = 0.73; 4v = 1.98; 5x = 1.88; M = 0.56 and prox. x = 0.82.

Terminalia. Spermatheca lightly pigmented, bulb-shaped, covered with tiny spines, duct partially invaginated (Figure 3B). Ovipositor elongated, sclerotized, with 13 marginal and six discal teeth, one long bristle, and two fine hairs (Figure 3C).

Variation in paratypes (dry mounted specimen). Head. Frontal length 0.23-0.27 mm, frontal index = 0.6-0.71, top to bottom width ratio = 1.31-1.36; distance of or3 to or1 = 0.07-0.09, distance of or3 to vtm = 0.09-0.12, or1-or3 ratio = 0.8-1.0, or2-or1 ratio = 0.22-0.57, distance of ocellar setae = 1.0-1.3 of frontal length, distance of postocellar setae = 0.60-0.68 of frontal length, vt index = 0.77-1.0; cheek index = 5.62-7.83; vibrissa index = 0.85-0.94; eye index = 1.20-1.27. Thorax length 0.81-0.89 mm, h index = 0.86-1.0. Transverse distance of dorsocentral setae = 2.17-3.0, dc index = 0.70-0.83. Distance between apical scutellar seta = 1. scut index = 1.08-1.25; sterno index = 0.92-0.95.

Etymology.

Named in recognition of the collection site, Zamora Chinchipe province of Ecuador.

Distribution.

Known only from the type locality.

Ecology.

Unknown. The type specimen was found in the banana-bait traps placed at the locality, which suggests that this species feeds on fermented fruits as do many other Drosophila species. This species has been reared with gelatin banana media devised by Rafael et al. (2000). The habitat is a relatively well-preserved montane forest.

Relationship to other species.

This species belongs to the guarani species-group. The most similar species are Drosophila urubamba Vilela & Pereira, 1993 and Drosophila tucumana Vilela & Pereira, 1985. Drosophila zamorana sp. n. is similar to D. urubamba but the most important difference is in the aedeagus. First, the distal end of the aedeagus in D. zamorana is narrower than in D. urubamba . Second, the form of the aedeagus in D. urubamba is bulkier than in D. zamorana . There is a little difference in the paraphyses; D. zamorana has some microtrichose areas surrounding the two small bristles that D. urubamba does not have. These differences distinguish these two species, mainly because of the cryptic external morphology.