2) Colocasiomyia grandis Toda, sp. nov.

(Figs 5B, 9E, 15B, 17)

Colocasiomyia sp. aff. stamenicola: Sultana et al., 2006: 694; Takano et al., 2011: 22; Fartyal et al., 2013: 768.

Diagnosis. Patch covered with only minute pubescence present on anterodorsal portion of fore tarsomere I (ch.13-0; Fig. 17A). Male abdominal sternite VI with single, large process bearing neither prominent seta nor sclerotized claw on apex but small setae on submedial to distal portion (Figs 9E, 17B).

Description (♂ and ♀; not repeating characters common to C. ecornuta sp. nov.). Head. Supracervical setae 5–6 per side, distally more or less curved, longer than inner occipital setae. Anterior reclinate orbital seta small, situated slightly behind proclinate orbital seta. Eye with stout, dense interfacetal setulae. Distance between antennal sockets wider than half of socket width. Cibarial, medial sensilla (3–4 per side) in parallel rows as wide as sensilla campaniformia; posterior sensillum 1 per side. Supralateral seta outside prementum 1 per side.

Thorax. Anterior dorsocentral setae far behind transverse suture (Fig. 5B). Prescutellar acrostichal setae present (Fig. 5B). Katepisternal setae large; posterior one longer than longest, postpronotal seta. Apical scutellar setae nearer to each other than to basal scutellar seta (Fig. 5B).

Wing. Costal setae in middle row all apically blunt, heavy, peg-like.

Abdomen. Male: sternites III and IV wider than long, medially notched on posterior margin; V medially concaved on posterior margin (Fig. 17B). Female: sternites IV and V medially concaved on posterior margin; VI longer than wide, deeply bilobed into lateral, narrow plates (Fig. 17C).

Male terminalia. Epandrium pubescent except for ventral portion, posteroventrally extended as ventral lobe pointed apically, with 16–19 setae as thick as cercal setae on ventral portion of each side but none on lateral to dorsal portion (Fig. 17D). Surstylus long, narrow plate with 4 somewhat trichoid, recurved setae apically, 1 nearly straight seta apicoventrally and 1 minute seta subapically (Fig. 17D). Median piece of subepandrial sclerite broad, somewhat quadrate plate; lateral pieces long, narrow. Cercal dorsal half pubescent and densely setigerous; ventral portion not pubescent, extended below, with small setae sparsely on surface and tiny setae densely on apical margin (Fig. 17D). Phallal sheath not pubescent, as thick as wide, apically somewhat hooked in lateral view, not projected at dorsobasal corner in lateral view; phallapodeme sclerotized plate directed nearly along phallal axis (Fig. 17E). Gonocoxites long, narrow slips (Fig. 17E).

Female terminalia. Epiproct and hypoproct pubescent (Fig. 17F). Oviscapt subapically widest, apically round, with 14–16 ovisensilla only on distal portion occupying less than 1/2 length of oviscapt (Fig. 17F).

Indices (range of 10♂ and 10♀): FW/HW = 0.50–0.72, ch/o = 0.41–0.56, prorb = 0.77–1.09, rcorb = 0.24–0.50, vb = 0.33–0.56, dcl = 0.50–0.67, sctl = 0.46–0.88, sterno = 0.42–0.78, orbito = 0.43–0.75, dcp = 0.64–0.87, sctlp = 0.98–1.26, C = 1.81–2.52, 4c = 0.85–1.20, 4v = 1.44–1.83, 5x = 0.77–1.36, ac = 2.43–2.96, M = 0.32–0.51, C3F [length of heavy setation in 3rd costal section / (length of heavy setation in 3rd costal section + length of light setation in 3rd costal section)] = 0.30–0.43.

Puparium (3rd instar larva). Segments with stout spicules on ventral surface; anterior spiracle with stalk ending in a whorl of 11–12 branches; stalk as long as longest branch; caudal segments not elongate, with many small spicules, ending in a pair of short posterior spiracles (Fig. 17G–I). Mouth hook strongly, triangularly expanded medioventrally in lateral view; distal blade strongly curved downward (Fig. 17J).

Holotype. ♂ (KIZ), “ Menglun, Xishuangbanna, Yunnan, China, 940 m a.s.l., 10.iii.2003, ex Alocasia odora (Roxburgh) K. Koch, M.J. Toda ”.

Paratypes. China: 10♂, 10♀, same data as the holotype; 5♂, 5♀, ditto except 22.v.2019, S. Ling leg.; 5♂, 5♀, ditto except 17.iv.2017, ex Colocasia esculenta (L.) Schott ; 2♂, 4♀, ditto except 7.v.2018, ex Leucocasia gigantea (Blume) Schott; 1♂ (#10149), 2♀ (#10495, #10496), Tongbiguan, Yingjiang, Yunnan, 1300 m a.s.l., 5.vi.2019, ex Alocasia yunqianum Ma, Li & Yin, Z. Ma leg. (KIZ, SEHU) .

Other specimens examined. Vietnam: 2♀, Pu Mat, Con Cuông District, Nghe An, 30.ix.2007, ex Alocasia aff. odora, M. Yafuso leg. (SEHU) .

Distribution. China (Yunnan), Vietnam.

Remarks. This species is unique, having the single process on the male abdominal sternite VI, among species of the cristata subgroup; all the species other than C. ecornuta sp. nov. have the paired processes (ch.24-1; Fig. 9F–R). On the other hand, the morphological similarity in the process on the male sternite VI (a trace of fusion or separation of the process, and the lack of apical claw; Fig. 9D,E) and the fore tarsus (the patch covered with only minute pubescence on tarsomere I, and the 4 pegs on II; Fig. 17A) suggests the relationship between C. grandis sp. nov. and the most basal species, C. stamenicola, of the C. colocasiae subgroup.

Etymology. Referring to the relatively large body size.