Tactusa assamia Fibiger

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

Tactusa assamia Fibiger , new species

( Plate 4 , figure 3; male genit. plate 14, figure 1)

Material examined. Holotype: male, NE India, Assam, Khasis Hills , -. x.1895, leg. W. Doherty, genit. prep. 3761 M. Fibiger, coll. BMNH.

Paratypes: 1 male with same data as holotype, but Upper Assam, 1895, without abdomen, leg. W. Doherty, BM 1915-113 , coll. BMNH (see also above under T. trigonifera ) .

Diagnosis. Imago (external). Wingspan: 11.5 mm.

Forewing: with very large, triangular, dark-brown and brown patch that extends from antemedial point on costa to apex, including fringes and tornal edge; a large patch in middle slightly lighter brown (apo.).

Crosslines: only terminal lines visible as blackish-brown interneural spots; fringes basally whitish, together forming a line.

Reniform stigma: invisible.

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.

Saccus: short; strongly built, V shaped.

Fultura superior: membranous.

Valvae: asymmetrical, right side broader; sacculus subbasally with a thumblike process, setose at tip (apo.). A similar process present in T. nilssoni .

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

Digitus: present, as a raised, heavily sclerotised hump (apo.).

Juxta and anellus plate: slightly asymmetrical, fused, almost quadrangular, ventro-laterally with heavily sclerotised bar, dorsally with ringlike circle (apo.).

Phallus: coecum very short; broad at ductus ejaculatorius; tapered smoothly from there; curved both before and after middle area (apo.).

Vesica: unarmed.

Female genitalia. Unknown.

Differential diagnosis. T. assamia differs from other members of species-group in large light brown patch in middle of large patch; in male genitalia, in saccular process, shape of ampulla, heavy sclerotisations of juxta-anellus plate, and shape of phallus.

Distribution. Known only from NE India, Assam.

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.