Thylacosceles Meyrick, 1889

Guan, Wei & Li, Houhun, 2016, Thylacosceles Meyrick new to China, with descriptions of four new species (Lepidoptera: Stathmopodidae), Zootaxa 4158 (2), pp. 213-220 : 213-214

Thylacosceles Meyrick, 1889

Thylacosceles Meyrick, 1889: 171 . Type species: Thylacosceles acridomima Meyrick, 1889 , by monotypy.

Generic characters. Adults small sized. Head ( Fig. 1 ) smooth, vertex with a transverse fillet; occiput broad and flat, about 1.3 times length of eyes' diameter, with longitudinally lined scales. Antenna shorter than forewing; scape elongately clubbed; flagellum filiform, stouter in male than in female, with extremely short cilia. Labial palpus ( Fig. 2 ) ascending, third palpomere usually shorter than second, pointed apically. Maxillary palpus extremely short. Forewing lanceolate, more or less uniform in color, costal margin usually with a large distal spot. Venation ( Fig. 8 ): R1 arising from basal 3/4 of upper margin of cell, R4 and R5 stalked for basal 2/5, R5 reaching costa before apex, CuA1 arising from lower angle of cell, CuA2 from basal 2/3 of lower margin of cell, 1A+2A not furcate basally. Hindwing narrow lanceolate; cilia about six times width of wing, Rs and M1 approximated at base, M2, M3, CuA1 and CuA2 subparallel. Hindleg ( Fig. 3 ) upturned and arched, forming a right angle in lateral view when in rest; hind tibia with mid spurs located at basal 1/3, dorsally with a tuft of long bristles from basal 1/3 to near apex, forming a triangular shape in lateral view, with whorls of dark bristles at apex. Abdominal tergites II–VII in male and II–VI in female with spines arranged in a slightly arched line along posterior margin ( Fig. 9 ).

Male genitalia: Gnathos slightly shorter than uncus. Tegumen branched from posterior portion and gradually narrowed to pointed anterior end. Valva usually with ampulla. Aedeagus stout; cornutus present or absent.

Female genitalia: Antrum developed. Ductus bursae usually shorter than antrum. Corpus bursae with signum.

Diagnosis. This genus is similar to Thylacosceloides Sinev, 1988 superficially by sharing a broad and flat occiput, but can be distinguished by the occiput having no deep longitudinal groove in male; in Thylacosceloides , the occiput has a deep longitudinal groove in male medially.

Distribution. Australian and Oriental regions.

Figures

FIGURES 1 − 7. Adults of Thylacosceles species. 1 − 4, T. nephroides sp. nov., holotype, ♂: 1, head (dorsal view); 2, head (lateral view, paratype, ♂); 3, hindleg; 4, adult; 5, T. clavata sp. nov., holotype, ♂; 6, T. cuneiformis sp. nov., holotype, ♀; 7, T. ellipsoidala sp. nov., holotype, ♂. (Scale bars = 2.0 mm).

FIGURES 8 − 9. Venation and abdomen of T. cuneiformis sp. nov., paratype, ♂: 8, venation, slide No. GW 14004 W; 9, abdomen (genitalia removed), slide No. GW 14004. (Scale bars = 0.5 mm).