Integrative species delimitation in the morphologically conservative Stegana subgen. Orthostegana (Diptera, Drosophilidae) Author Wang, Ya-Lian https://orcid.org/0000-0002-4361-0437 Department of Entomology, South China Agricultural University, 483 Wushan-lu, Guangzhou 510642, Guangdong, P. R. China Author Peng, Zi-Qi https://orcid.org/0009-0002-7444-2082 Department of Entomology, South China Agricultural University, 483 Wushan-lu, Guangzhou 510642, Guangdong, P. R. China Author Jin, Feng-Liang https://orcid.org/0000-0002-3780-3988 Department of Entomology, South China Agricultural University, 483 Wushan-lu, Guangzhou 510642, Guangdong, P. R. China Author Chen, Hong-Wei https://orcid.org/0000-0003-3175-8060 Department of Entomology, South China Agricultural University, 483 Wushan-lu, Guangzhou 510642, Guangdong, P. R. China Author Huang, Jia https://orcid.org/0000-0002-7018-0890 Department of Entomology, South China Agricultural University, 483 Wushan-lu, Guangzhou 510642, Guangdong, P. R. China hj@scau.edu.cn text Arthropod Systematics & amp; Phylogeny 2023 2023-06-15 81 581 610 http://dx.doi.org/10.3897/asp.81.e102683 journal article http://dx.doi.org/10.3897/asp.81.e102683 1864-8312-81-581 CA56E9F0B4264014B20BD7C455FD65A7 E6F5D6150A225AFBB372E719EBBEDB68 3.2.1.8. Stegana (Orthostegana) obscurala Peng & Chen sp. nov. Figs 8C-F , 10D , 19 Diagnosis. This species closely resembles S. (O.) aini sp. nov. in the shape of both male and female terminalia (Figs 12 , 19 ), but can be distinguished from the latter by having the pleura with a distinct brown to dark brown longitudinal stripe above (Fig. 8D, F ); the mesotarsus ventrally with 2 rows of black, apically blunt, stout spines; metatarsus with 12/6+1 spines; 2nd to 4th segments with 6/1, 3/1, and 2/1 spines, respectively (Fig. 10D ); pregonite with ca. 3 sensilla distally (Fig. 19C, D ). Figure 19. Stegana (Orthostegana) obscurala Peng & Chen sp. nov. , male ( A - D ) and female terminalia ( E ). A Epandrium, surstylus, and cercus in lateral view; B Surstylus in ventral view; C , D Hypandrium, phallapodeme, pregonite, aedeagus, and aedeagal sheath in ventral and lateral views; E Eighth sternite in ventral view. Scale bars = 0.1 mm. Description. Male and female. Head : Ocellar triangle dark brown, with 2 small setae posterior to ocellar setae. Postocellar seta absent. Frons brown, with numerous minute interfrontal setulae. Pedicel and first flagellomere yellow, with black pubescence. Face brown, with narrowed, black band on lower margin. Gena brownish. Clypeus mostly brownish. Palpus brownish. Thorax : Mesonotum mostly yellow to brown (Fig. 8C, E ). Scutellum yellow in males (Fig. 8C ), dark brown in females (Fig. 8E ). Halter mostly brownish, with a yellow patch at knob (Fig. 8D-F ). Legs yellowish (Fig. 10D ). Abdominal tergites : brown to black. Male terminalia : Epandrium mostly pubescent except for anterior and ventral margins, with ca. 20 setae on dorsal to posterior portions per side (Fig. 19A ). Surstylus separated from epandrium, with ca. 2 long and 10 short peg-shaped prensisetae and a few setae near posteroventral margin (Fig. 19B ). Pregonites separated and small, slightly expanded distally (Fig. 19C, D ). Aedeagus pubescent distally, with some hairs apically (Fig. 19C, D ). Female terminalia : Eighth sternite with 4 rows of asymmetrical peg-shaped prensisetae subposteromedially and posterolaterally, and with 3 sensilla distally per side (Fig. 19E ). Measurements and indices. BL = 3.13 mm in holotype (range in 2♂ and 2♀ paratypes: 2.60-3.00 in ♂, 2.87-4.21 in ♀), ThL = 1.37 mm (1.00-1.13 in ♂, 1.07-1.60 in ♀), WL = 2.33 mm (1.90-2.17 in ♂, 2.20-2.77 in ♀), WW = 1.03 mm (0.93-0.97 in ♂, 1.00-1.27 in ♀), arb = 6/5 (6-7/4-6), avd = 0.92 (0.88-0.92), adf = 1.71 (1.71-2.13), flw = 1.86 (2.00-2.17), FW/HW = 0.38 (0.32-0.40), ch/o = 0.15 (0.13-0.16), prorb = 0.90 (0.82-0.90), rcorb = 0.50 (0.50-0.65), vb = 0.41 (0.40-0.75), dcl = 0.54 (0.38-0.50), presctl = 0.39 (0.40-0.50), sctl = 1.33 (1.33-1.50), sterno = 0.84 (0.77-0.84), orbito = 1.80 (1.67-2.00), dcp = 0.24 (0.22-0.29), sctlp = 0.90 (0.89-1.17), C = 2.75 (2.20-2.50), 4c = 0.84 (0.84-1.00), 4v = 1.79 (1.63-1.84), 5x = 1.29 (1.25-1.50), ac = 16.00 (13.33-16.00), M = 0.47 (0.42-0.53), C3F = 0.75 (0.69-0.76). Distribution. China (Yunnan). Type material examined. Holotype : ♂ (SCAU, No. 112125), China: Wangtianshu, Mengla, Yunnan, 21°37′10″N , 101°35′17″E , altitude 570 m, 9.v.2012, swept from tussock, H.W. Chen. Paratypes : 2♂, 2♀ (SCAU, Nos. 112126-29), H.W. Chen, J.J. Gao, other data same as the holotype. Etymology. From the Latin word " obscurus " (= obscure), referring to the mostly dark-colored abdominal tergites.