Rheocricotopus (Psilocricotopus) bannaensis Niitsuma & Tang, 2026, sp. nov.

Rheocricotopus (P.) bannaensis sp. nov. urn:lsid:zoobank.org:act: 220F413F-7084-4FC3-A3C5-100A7D2A781F Fig. 13, Table 11 Diagnosis Male Abdomen bicoloured, with tergites I, IV and VII yellow, remaining tergites dark brown. AR relatively low (less than 0.5). Humeral pit large, oval. Wing cuneiform with very long costal extension. Inferior volsella digitate with a longitudinal row of setae. Crista dorsalis large, triangular, located at middle of gonostylus. Female Tergites I, IV and VII yellow, remaining tergites dark brown. Etymology From the type locality, Xishuangbanna, abbreviated as ‘Banna’ in Chinese. Type material Holotype CHINA – Yunnan • ♂; Xishuangbanna, Yiwu, Guafengzhai; 22°00′ N, 101°35′ E; 1360 m a.s.l.; 26 Apr. 2017; J. Chen leg.; JNU, JNU 170429003. Paratypes CHINA – Yunnan • 1 ♂; Xishuangbanna, Mengla, Bubang, Xishuangbanna Tropical Rainforest National Park, Wangtianshu Scenic Area; 21°37′ N, 101°35′ E; 710 m a.s.l.; 25 Apr. 2017; J. Chen leg.; JNU, JNU 170511007 • 1 ♀; Honghe, Pingbian, Daweishan NNR; 22°55′ N, 103°41′ E; 1800 m a.s.l.; 14 Jun 2017; J. Chen leg.; JNU. Description Male (n = 2) Total length 2.0– 2.1 mm. COLOURATION. Head dark brown on vertex. Thorax mostly dark brown with yellow pleural membrane; scutal vittae indistinct. Abdomen (Fig. 13A) bicoloured; T I, IV and VII entirely yellow, remaining tergites dark brown. Legs brown. HEAD. Temporals 2. AR 0.36–0.37. Clypeus with 6–9 setae. Lengths (μm) of Pm 1–5: 27–32, 44–49, 101–113, 113–123, 231–239, respectively. Pm 4 /Pm 3 1.1, Pm 5 /Pm 4 1.9–2.0. Pm 3 with at least 8 SCl on 2 subapical oval depressions. THORAX (Fig. 13B). Lateral Aps 2. Ac 12 (1), longest 12 (1) μm long; Dc 5, including 1 H; Pa 3; Scts 4. HP oval, relatively large, its posterior margin partly visible. WING (Fig. 13C). Length 1.4–1.5 mm. AnL much reduced; wing cuneiform, widest at around end of Cu 1. C extension 74–91 μm long. VR 1.1. R with 3–6 setae; R 1 and R 4+5 bare. Sq with 0–1 seta. LEGS. P 1 with ti spur 27 μm long; P 2 with 2 ti spurs, both 15 μm long; P 3 with 2 ti spurs 34–39 and 15–17 μm long. P 2 without Such. P 3 with ti comb of 11–12 bristles. Lengths and proportions of legs as in Table 11. ABDOMEN. Hypopygium (Fig. 13D) with AnP robust, bearing 17 lateral setae. Gc 135–148 µm long, 3.8–3.9 × as long as broad at middle, subapically with triangular posteromedial projection; SVo thin, triangular, rounded at apex; IVo digitate, 52–59 µm long with apical and ventral fine setae, and longitudinal row of long ventral setae. Gs 74–76 µm long, medially with well-developed, triangular CD. HR 1.8–2.0. Female (n = 1) Total length 2.1 mm. COLOURATION. Similar to male. SCa pale. HEAD. Temporals 4. Lengths (μm) of Fm 1-5: 47, 32, 44, 27, 54, respectively. AR 0.36. Clypeus with 6 setae. Lengths (μm) of Pm 1–5: 32, 57, 108, 121, 278, respectively. Pm 4 /Pm 3 1.1, Pm 5 /Pm 4 2.3. Pm 3 with numerous SCl on 2 oval depressions. THORAX (Fig. 13E). Lateral Aps 4. Ac 17, Dc 6, including 2 H; Pa 3; Sct 3. HP oval, large. WING. Length 1.9 mm. C extension very long, 135 μm long. VR 1.1. R, R 1 and R 4+5 with 11, 7 and 18 setae, respectively. Sq bare. LEGS. P 1 with one ti spur 34 μm long; P 2 with 2 ti spurs 22 and 20 μm long; P 3 with 2 ti spurs 52 and 22 μm long, and with ti comb of 13 bristles. Lengths and proportions of legs as in Table 11. GENITALIA (FIG. 13F). Gp VIII divided into rounded VlL and narrow DmL; ApL distinct. S VIII with 6 setae. T IX (Fig. 13G) undivided, with 9 setae including 4 short setae. Gc IX with 11 setae on each side. No 140 μm long. Ce 57 μm long. SCa and ducts damaged. Pupa and larva Unknown. Distribution Rheocricotopus bannaensis sp. nov. is known only from Yunnan Province in Oriental China. Remarks The species belongs to the orientalis group based on a cuneiform wing with a well-extended costal vein and few squamal setae, the bicoloured abdomen, the very long inferior volsella, and the large crista dorsalis located in the mid-gonostylus (Wang & Saether 2001: 239–240). Within the species group, the male most resembles that of R. (P.) villiculus Wang & Saether, 2001 in the largely dark brown abdomen with entirely yellow tergites I, IV and VII, but differs in the entirely dark brown tergite II, the relatively low antennal ratio (AR less than 0.4), the mid tibia is normally with two spurs, in addition to an anal tergite without lateral setal tufts. According to Wang & Saether (2001: 238–239), the male of R. (P.) villiculus is characterized by a yellowish median patch on tergite II, the relatively high antennal ratio (AR 0.6), the mid tibia with only one spur, and the anal tergite with a pair of setal tufts on the base of anal point.