Tactusa motuoensis, Han & Kononenko, 2021

Han, Hui Lin & Kononenko, Vladimir S., 2021, A new species of Tactusa Fibiger, 2010 from Autonomous Region Xizang, China (Lepidoptera, Erebidae, Hypenodinae). Taxonomic study of Micronoctuini. Contribution II, Zootaxa 4933 (2), pp. 295-300 : 296-299

Tactusa motuoensis sp.n.

( Figs 1–3, 5, 6, 8 , 23–26 )

Type materials. Holotype: male, China, Aut. Reg. Xizang (Tibet), Motuo City (= Medog ), 16–17.iv.2018 (legs. Han Hui-Lin & Da Wa), genitalia. prep. no. hhl-4012-1( NEFU) . Paratypes: 3 males, Aut. Reg. Xizang, Motuo, Beibeng , 13 & 16.viii. 2016 (legs. Qi M.J. & Yang X.F.), genitalia. prep. no. hhl-4031-1( NEFU) ; 3 male, 1 female, same data as holotype, genitalia prep. no. hhl-4011-1(male), hhl-4016-2 (female) ( NEFU) .

Diagnosis. The new species in the superficial characters and male genitalia is similar to T. schnacki ( Fig. 4, 7 ), but in close comparison of two these species it differs by following characters:

Adult of T. motuoensis ( Figs 1–3 ) differs from T. schnacki ( Fig. 4 ) by sharp apex of forewing (blunt in T. schnacki ); ground colour of forewing pale, but dark in T. schnacki ; antemedial line of T. motuoensis rather broad and indidtinct, with black spot at R vein, that rather thin and distinct, without black spots in T. schnacki ; postmedial line in T. motuoensis is indistinct, rather smoothly waved, but distinct, intensively waved in T. schnacki ; subterminal line dispersed, thin and black at medial part in T. motuoensis , but distinct and dark black in T. schnacki .

In the male genitalia T. motuoensis ( Figs 5, 6 ) differs from T. schnacki ( Fig. 7 ) by the shape of anellus plate, which is narrower, with long and sharp apical angle, bent right at the top, vs more massive with short and blunt apex slightly bent right in T. schnacki ; sacculus narrow and long on whole length of valva in T. motuoensis vs broad and long as 2/3 a length of valva in T. schnacki ; valva slightly narrower with smooth costa in its apical part, vs rather broad valva with costa angled apically in T. schnacki ; clavus in left valva in T. motuoensis is broader and more massive compared with that in T. schnacki ; cucullus somewhat broader, with larger ventral lobe than in T. schnacki . Aedeagus in T. motuoensis is more massive, smoothly curved, with cylindrical coecum, long prominent dorsal plate and broad carina armed with two thorn-shaped spines but in T. schnacki the aedeagus is slightly curved twice, with conical coecum, rather short and straight dorsal plate; carina armed with two teeth-shaped spines, among them posterior one is bigger than anterior; vesica in T. motuoensis is spirally coiled medially, bearing a short mastoid-shaped cornuti in ventral and basal parts, that of T. schnacki is slightly spiral medially, bearing single bar-shaped cornutus in basal part.

Description. Adult ( Figs 1–3 ). Wingspan 11–13 mm. Head smooth, yellowish brown; antenna filiform, light yellowish brown. Patagia black; tegulae yellowish grey; thorax yellowish brown. Abdomen dark brown, with dorsal tuft on basal segment. Forewing relatively long, triangular; ground colour of forewing beige-brown, spread with small and darker brown grains, with a blackish brown to dark brown patch on the basal part of costal margin. Antemedial line black, extended from costa to R vein, then incurved to inner margin, with black spot at R vein, inside slightly pale grey; median line absent; postmedial line thin, greyish brown, extended from costa to R vein, then curved to 2A, and slightly incurved to inner margin, in outer side slightly pale grey, forms dark black dot at costal margin; subterminal line broad, black and slightly excurved, light in costal area; terminal line thin, grey; reniform spot greyish white, as small dot; ground colour rather pale between basal and antermedial lines with thin brownish black rectangle-shaped band at costal area in base of median and postmedial lines; apex rather sharp. Hindwing pale greyish brown diffused; discal spot halo-like, distinct; vein visible; terminal part of wing diffused, darker than medial, terminal line light grey; outer margin incurved at 2M.

Male genitalia. ( Figs 5, 6 ). Tegumen thin, relatively long and narrow, somewhat longer than vinculum. Saccus prominent, sharp. Juxta tongue-shaped, strongly sclerotized, slightly incurved apically, with egg-shaped window at centre. Anellus plate triangular, sclerotized, with a sharp beaks-shaped apical angle bent right. Valves slightly asymmetrical, left valva narrower than right one; sacculus narrower in left valva, with large sclerotized horn-like clavus in basal part; costa swell nearby cucullus, left “neck of valva” slightly narrower then right one; cucullus slightly asymmetrical, ear-shaped, heavy haired, its ventral lobe much broader than dorsal one, on left valva cucullus some smaller then on right one. Aedeagus curved subapically, gradually constricted to apex; coecum broad, with prominent plate nearby ductus ejaculatorius, carina rather broad, bearing two small spines. Vesica tubular, spirally coiled medially, with short, hardly sclerotized mastoid-shaped cornutus on ventral of the basal part, with a tiny thin cornutus in terminal diverticulum.

Female genitalia. ( Fig. 8 ). Ovipositor cone-shaped. Apophyses posteriors thin, 4 times longer than anteriores ones; that are short, small and mastoid. Ostium displaced laterally left, slightly sclerotized. Antrum short, heavily sclerotized. Ductus bursae membranous, narrow, slightly coiled, about 1.5 times as long as corpus bursae. Corpus bursae heart-shaped, membranous; signum cross-shaped at the middle and rear parts, its longitudinal line darker and stronger than transverse line.

Distribution and bionomics. ( Figs 24–26 ). The species is known from vicinity of Motuo village, Xizang Autonomous Region of China. The new species has been collected in April and August in the tropical rain forest zone, at the altitude between 810 and 1120 m. Flight probably in two generations.

Etymology. This species name is derived from the locality of the type, Motuo.

Figures

FIGURES 1–8. Tactusa spp., adults (1–4) and male (5–7) and female genitalia (8). 1, 5. T. motuoensis sp.n. Holotype. China, Xizang. HHL-4012-1 (NEFU); 2, 3, 6, 7. Ditto, paratypes. China, Xizang. Genitalia slides: 6. HHL-4031-1 male (NEFU); 8. HHL-4016-2 female (NEFU); 4, 7. T. schnacki. Holotype. North India (after Fibiger 2010).

FIGURES 9–26. Tactusa spp., adults (9–16), male genitalia (17–23), distribution map and habitats of T. motuoensis (24–26). 9, 17. T. virga (after Fibiger et al., 2011); 10, 14. T. flexus (after Fibiger et al., 2011); 11, 19. T. pars Fibiger, 2010 (after Fibiger, 2010), male genitalia HHL-4032-1; 12, 20. T. motuoensis sp.n. Holotype. China, Xizang, male genitalia HHL-4012-1; 13, 21. T. topi (after Fibiger, 2010); 14, 15, 22. T. discrepans (after Fibiger, 2010); 16, 23 T. brevis (after Fibiger et al., 2011); 24. Distribution map of T. motuoensis; 25, 26. Collecting sites of T. motuoensis in vicinity of Motuo in the northernmost tropical rain forest: 25 - altitude 1121m; 26 - altitude 830m.