Tactusa discrepans Fibiger, 2010

FIBIGER, MICHAEL, 2010, Revision of the Micronoctuidae (Lepidoptera: Noctuoidea) Part 3, Taxonomy of the Tactusinae, Zootaxa 2583 (1), pp. 1-119 : 32-33

Tactusa discrepans Fibiger , new species

( Plate 4 , figure 4; male genit. plate 14, figure 2)

Material examined. Holotype. Male , Thailand, Chieng Mai , Doi Inthanor Nat. Park, Siriphum, 1200–1300 m, 21.–24.x.1984, leg. O. Karsholt et al., genit. prep. 2947 M. Fibiger, coll. ZMUC.

Paratypes. 3 males. 1 male, Thailand, Chiang Mai Prov., Doi Inthanor, Maeo Khan Klang , 1300 m, 16– 17.x.1983, leg. M. Owada, genit. prep. 3337 M. Fibiger ; 1 male, N Thailand, Doi Suthep Pui , 1200 m, 26– 28.vii.1989, leg. J.D. & D.J. Bradley & Angoon Lewvanich, Brit.Mus. 1981-150, genit. prep. 3189 M .

Fibiger; 1 male, Thailand, Chiang Mai, Chiang Dao WS, h’way 1322 to Wiang Haeng, 5 km from Khun Mae Ngaay c’point, 780 m, 17.iv.1994, leg. IJ. Kitching et al., genit. prep. 3188 M. Fibiger, BMNH (E) 1994-97. Colls ZMUC, BMNH, and NSMT.

Diagnosis. Imago (external). Wingspan: 12 mm.

Forewing: with a very large triangular, black patch, including fringes, that extends from antemedial point on costa to apex and to tornal edge; few light-brown patches present within large patch (apo.).

Crosslines: parts of postmedial and subterminal lines present, light brown; terminal lines indicated by blackish-brown interneural spots; parts of fringes basally light brown, together forming a line.

Reniform stigma: present; very narrow; yellowish, traceable only as slight widening of postmedial line, outlined broadly by black (apo.).

Hindwing: dark grey, with indistinct discal spot.

Underside: unicolorous grey.

Abdomen: grey, with black crest dorsally on first segment.

Male genitalia. Tegumen: relatively strongly built.

Vinculum: well built.

Saccus: short; strongly built, broadly V shaped.

Fultura superior: membranous.

Valvae: asymmetrical, one on left broader; sacculus subbasally with a broad-based triangular process, setose at tip (apo.).

Ampulla: forming a cross with axis of valva; slightly asymmetrical, broadest by valva; arms broad, dorsal arm longer, with small, stout spines at tip, and ventral arm equally broad throughout rounded apically (apo.).

Digitus: present; hill-like and heavily sclerotised (apo.).

Juxta and anellus plate: asymmetrical, fused, quadrangular ventrally and rounded dorsally, with hole for phallus at right side by rounded edge (apo.).

Phallus: coecum very short, broad at ductus ejaculatorius, tapered conelike from there and bent ventrally, then curved smoothly upwards to tip (apo.).

Vesica: unarmed.

Female genitalia. Unknown.

Differential diagnosis. T. discrepans differs from other members of second half of species-group in large blackish patch, with hardly visible, very narrow reniform stigma; in male genitalia, in triangular saccular process, rounded digitus, shape of ampulla, and ventrally quadrangular juxta-anellus plate.

Distribution. Known from four specimens from N Thailand, taken in April, July, and October.

Figures

PLATE 4. Figures 1–8. Tactusa, Conspica, and Tumula species, adults. 1, T. similis, female holotype, Thailand, Chiang Mai; 2, T. constrictor, male holotype, Laos, Vientiane; 3, T. assamia, male holotype, India NE, Assam; 4, T. discrepans, male holotype, Thailand, Chiang Mai; 5, T. spadix, male holotype, Laos, Vientiane; 6, T. pars, male holotype, Thailand W, Kanchannaburi; 7, Conspica inconspicua, male holotype, Thailand, near Ban Nam Lee Pattana; 8, C. parainconspicua, male holotype, Thailand, Chiang Mai.