Drosophila chichu, Peñafiel-Vinueza & Rafael, 2019

Peñafiel-Vinueza, Ana Danitza & Rafael, Violeta, 2019, Five new species of the Drosophila tripunctata group (Diptera: Drosophilidae) from Podocarpus National Park, Ecuador, European Journal of Taxonomy 494, pp. 1-18 : 9-11

Drosophila chichu sp. nov.

urn:lsid:zoobank.org:act:3F0DBF0C-E97E-4291-AE59-E298DC96AF7A

Fig. 5

Diagnosis

Aristae with 5 dorsal and 2 ventral branches plus terminal fork. Two prominent oral bristles, 2 nd slightly smaller than 1 st. Thorax yellowish brown. Legs yellowish brown. Wings yellowish brown, dM-Cu slightly clouded. Abdomen yellow with dorsal midline, from 2 nd to 5 th tergites with triangular pigmentation which becomes thinner laterally, 6 th tergite with median spot. Cerci not fused to epandrium. Hypandrium shield-shaped. Gonopod bearing one long bristle. Aedeagus sclerotized and tubular, with a basal ventral bump, ventrally with an apical concavity. Paraphyses fused to gonopod bearing one bristle.

Etymology

In the Kichwa language, ‘ chichu ’ = ‘pregnant’. The aedeagus has a ventral bump which resembles a woman’s pregnant abdomen.

Material examined

Holotype

ECUADOR • ♂ (dissected, terminalia in microvial); Loja Prov., Cajanuma , 2800 m a.s.l.; 04°06′58.9″ S, 79°10′11.9″ W; 19 Nov. 2015; A. Peñafiel leg.; A. Peñafiel and V. Rafael det.; QCAZ-I 3356.

Paratype

ECUADOR • 1 ♂ (dissected, terminalia in microvial); same data as for holotype; QCAZ-I 3357 .

Description

Male Holotype external morphology: total length (body + wings) 4.67 mm, body length 3.56 mm. Body color yellowish brown.

HEAD. Aristae with 5 dorsal and 2 ventral branches plus terminal fork and small hairs. Orbital plate yellowish brown, frontal length 0.33 mm; frontal index = 0.68, top to bottom width ratio = 1.35. Medial vertical seta closer to lateral vertical seta, vt index = 0.87; or1–or3 and or2–or1 ratio could not be calculated (broken setae on holotype). Ocellar triangle yellowish brown, ocellus yellow. Cheek index = 6.5. Two oral bristles, 2 nd slightly smaller than 1 st bristle, vibrissa index = 1.07. Carina not sulcate. Red eyes. Eye index = 1.20.

THORAX. Yellowish brown, thorax length 0.89 mm, acrostichal hairs in 2 rows between two anterior dorsocentral setae. h index = 0.79; dc index could not be calculated (broken setae on holotype). Medial katepisternal seta slightly smaller than anterior seta. Legs yellowish brown.

WINGS. Yellowish brown, dM-Cu slightly clouded. Alar length 2.86 mm, alar width 1.33 mm. Alar indices: alar = 2.12; C = 3.24; ac = 2.10; hb = 0.19; 4c = 0.64; 4v = 1.22; 5x = 1.42; M = 0.42 and prox. x = 0.41.

ABDOMEN. Yellow with dorsal midline, 1 st tergite yellowish brown, 2 nd to 5 th tergites with triangular pigmentation which becomes thinner laterally, 6 th tergite with a median spot ( Fig. 5A ).

MALE TERMINALIA. Epandrium dorsally microtrichose, with 2 lower bristles, ventral lobe with 3 bristles on each side. Cerci microtrichose and not fused to epandrium. Surstylus with 10 primary teeth on right side and 9 on left, 10 marginal bristles on each side ( Fig. 5B ). Hypandrium shield-shaped, slightly sclerotized. Gonopod bearing one bristle ( Fig. 5C ).

AEDEAGUS. Sclerotized and tubular with a basal ventral bump, ventrally with an apical concavity, dorsally membranous, with bright studs. Ventral rod absent. Paraphyses fused to gonopod bearing one bristle. Aedeagal apodeme sclerotized and curved ( Fig. 5D–F ).

Distribution

Known only from the type locality.

Relationship to other species

This species belongs to the tripunctata group. The general shape of the male terminalia, particularly that of the aedeagus, suggests a relationship with D. cundinamarca Vilela & Bächli, 2000 and D. pilaresae Vela & Rafael, 2001 .

Figures

Fig. 5. Drosophila chichu sp. nov. Holotype, ♂ (QCAZ-I 3356). A. Abdomen. B. Epandrium, cerci, surstylus, decasternum. C. Hypandrium, gonopods and paraphyses in ventral view. D–F. Aedeagus in ventral, lateral and dorsal view, respectively.