Fustis biextuta Fibiger

FIBIGER, MICHAEL, 2010, Revision of the Micronoctuidae (Lepidoptera: Noctuoidea) Part 3, Taxonomy of the Tactusinae, Zootaxa 2583 (1), pp. 1-119 : 47-48

Fustis biextuta Fibiger , new species

( Plate 6 , figure 2; male genit. plate 15, figure 4)

Material examined. Holotype: male, Thailand, Tham Sakoe Nat. Park headquarters, 19’23’ N, 100’38’ E, 29–30.xi.2003, leg. L. Peregovits et al., coll. HNHM.

Paratypes. 3 males with same data as holotype, but genit. prep. 6071 M. Fibiger. Colls HNHM and MF .

Diagnosis. Imago (external). Wingspan: 12–13 mm.

Head, patagia, anterior part of tegulae, prothorax, basal part of costa, triangular patch of medial area, major part of subterminal, and terminal area, including fringes: black.

Forewing ground colour: beige suffused with light-brown scales, subterminal area with beige-brown patches.

Abdomen: dark grey, with dorsal tuft on basal segment.

Reniform stigma: small, yellow, black outlined.

Hindwing: beige; with narrow brown terminal line and indistinct discal spot; fringes white basally, otherwise beige.

Underside: forewing grey brown, hindwing grey.

Male genitalia. Tegumen: long, medially narrow; basally and dorso-laterally broad, platelike (apo.).

Vinculum: two branched; centre one barlike; posterior one branchlike, not curved.

Saccus: short, broadly V shaped.

Valvae: asymmetrical; relatively long.

Ampulla: slightly asymmetrical, dorsal lobe twice as broad as ventral fingerlike lobe (apo.).

Digitus: small, triangular, apically setose.

Anellus plate: prominently asymmetrical; with short, free, curved, heavily sclerotised brushlike structure; head on one side clothed with stout setae (apo.).

Juxta: trapezoid, with medial cleft on dorsal side.

Phallus: coecum short and broadly triangular; broadest by ductus ejaculatorius; subapically smoothly and upwards curved 90 o to pointed tip (apo.).

Vesica: armed with small plate.

Differential diagnosis. F. biextuta differs from other Fustis species in:

- beige ground-colour, with contrasting wing pattern;

male genitalia, in

- tegumen basally and dorsally with platelike features;

- shape of ampulla, dorsal part broad, and ventral part fingerlike;

- smoothly curved, brushlike anellus; and

- phallus subapically curved upwards.

Distribution. F. biextuta known only from Thailand.

Figures

PLATE 6. Figures 1–8. Fustis, Bruma, Costasensora, and Longiantrum species, adults. 1, F. sensora, male, Thailand N, Chiang Mai; 2, F. biextuta, male holotype, Thailand, Tham Sakoe Nat P.; 3, F. extuta, male holotype, Thailand, Mae Hong Son; 4, F. gregerseni, male holotype, Thailand W, Uthai Thani; 5, F. s-forma, male holotype, Thailand NE, Ban Nam Lee Pattana; 6, F. papei, female holotype, Thailand, Nakhon Nayok; 7, Bruma parvus, male holotype, Indonesia, North Sumatra; 8, Costasensora honeyi, male holotype, Malaysia, Sarawak.