Stegana (Steganina) idiasta Cui & Chen

WANG, YA-LIAN, LI, BING-XUE, CUI, MENG-DI, ZHANG, YUAN, WANG, LE, ZHANG, CAI-HONG, TSAUR, SHUN-CHERN, CHEN, HONG-WEI & HUANG, JIA, 2023, Revision of the subgenus Stegana (Steganina) from China, with assessment of species delimitation using DNA barcodes (Diptera, Drosophilidae), Zootaxa 5250 (1), pp. 1-109 : 77

Stegana (Steganina) idiasta Cui & Chen , sp. nov.

( Figs. 9I, 9J, 42D–F)

Diagnosis. This species is similar to S. (S.) curvitabulata sp. nov. in the shape of epiproct, cercus ( Figs. 35A, 42D), and hypoproct ( Figs. 35C, 42F), but can be distinguished from the latter by having the palpus large, mostly yellow, distally slightly grey ( Fig. 9J); the epiproct lacking sensilla, with some setae on distal 2/3 ( Fig. 42D); the 8th sternite not curlied laterally, glabrous on basal 2/3, with several short setae and some pubescence on distal 1/3 ( Fig. 42E).

Description. Female: First flagellomere brownish. Clypeus yellow. Mesonotum brownish yellow medially, yellow laterally ( Fig. 9I). Katepisternum yellowish ( Fig. 9J). Scutellum brownish yellow medially, brown laterally ( Fig. 9I). Halter mostly grey ( Fig. 9J). Fore femur with a row of 3 long setae on distal part of posteroventral surface. Abdominal tergites dark brown ( Fig. 9I, J); sternites brown, about 2 times as wide as long. Female terminalia ( Fig. 42D–F): Cercus and hypoproct with numerous setae and much pubescence ( Fig. 42D, F).

Measurements and indices. BL = 3.15 mm in holotype (2.87–3.68 in 2♀ paratypes), ThL = 1.57 mm (1.49– 1.56), WL = 2.63 mm (2.88–3.08), WW = 1.21 mm (1.17–1.26), arb = 7/4 (7/4–5), avd = 0.78 (0.80–0.86), adf = 1.51 (1.17–1.24), flw = 2.92 (2.54–2.67), FW/HW = 0.35 (0.36–0.38), ch/o = 0.18 (0.21–0.22), prorb = 1.04 (0.78–0.89), rcorb = 0.88 (0.66–0.68), vb = 0.88 (0.77–0.93), dcl = 0.41 (0.50–0.54), presctl = 0.53 (0.46–0.59), sctl = damaged (1.80–1.89), sterno = 0.90 (0.78–0.82), orbito = 2.00 (1.66–1.82), dcp = 0.34 (0.34–0.40), sctlp = 1.87 (1.61–2.00), C = 1.71 (1.70–1.73), 4c = 1.36 (1.26–1.30), 4v = 1.95 (1.86–1.89), 5x = 1.21 (1.56–1.91), ac = 13.25 (19.33–23.60), M = 0.65 (0.62–0.66), C3F = 0.66 (0.61–0.62).

Type materials. Holotype ♀ ( SCAU, No. 125784, DNA #2189), Yixiang, Pu'er , Yunnan, 22°44'19''N, 101°07'01''E, alt. 1400m, 13.v.2012, ex tree trunk, H.W. Chen . Paratypes: 2♀ ( SCAU, Nos. 125785, 86, DNA #2761, 2762), other data same as holotype .

Distribution. China (Yunnan).

Etymology. From the Greek word " idiastçs " (= hermit), referring to the Steganina flies being reclusive in the forest.