Eugauria Snellen, 1901

Wu, Zhi-Gang, Chen, Fu-Qiang & Wu, Chun-Sheng, 2015, Review of the genus Eugauria Snellen (Lepidoptera: Crambidae: Musotiminae) in China, with descriptions of two new species, Zoological Systematics 40 (4), pp. 470-475 : 470-472

Eugauria Snellen, 1901

Eugauria Snellen, 1901 . Tijdschr. Ent., 43: 290; Speidel & Mey, 1999. Tijdschr. Ent., 142: 138. Type species: Eugauria compactalis Snellen, 1901 , by monotypy.

Descriptions. Small size. Head and thorax dark; labial palpi upturned, second segment slender and third segment pointed; maxillary palpi upturned; proboscis relatively short.

Venation ( Fig. 1 ). Forewing with vein Sc arising from base to middle of costa; R 1-5 arising from the upper angle of cell, R 1 close to but not stalked with R 2+3+4, R 2, R 3 and R 4 anastomosed, R 2+3+4 stalked with R 5; M 1 arising from 1/3 of discocellulares; M 2 arising above lower angle of cell; M 3 stalked with Cu 1, arising from lower angle of cell; Cu 2 arising from before lower angle of cell. Hindwing with Sc+R 1 and Rs stalked, arising from before upper angle of cell; M 1 arising from upper angle of cell; M 2, M 3 and Cu 1 arising nearby of lower angle of cell; Cu 2 arising before lower angle of cell.

Wing patterns. Forewing dark fuscous; a dark spot at upper angle of cell, sometimes blurry; a larger white patch at postmedial area, extending from costa to Cu 1; a smaller crescent white patch present or absent, at the outside of the apical yellow band; a yellow band between the white patches. Hindwing dark fuscous; a dark spot at middle of cell, sometimes blurry; anal angle with an incision; submarginal band with 5 connected black eye spots, eye spots with silvery spots centrally.

Male genitalia. Uncus and gnathos slender; gnathos with dorsal teeth at apex; tegumen with inverse V-shaped ridge dorsally; valva broadened form base to distal; transtilla present; sacculus broad and sclerotized, usually with a spine-like apical harpe; vinculum long; saccus rounded; juxta plate-like; aedeagus slender and sclerotized.

Female genitalia. Anal papillae narrow, with long setae; apophysis posterioris and anterioris relatively short; ostium bursae sclerotized; ductus seminalis arising from below ostium bursae; corpus bursae membranous, usually with signa.

Biology. The species of Eugauria feed on ferns, just as Nephrolepis Schott.

Distribution. Oriental Region ( China, Malaysia).

Remarks. The species of this genus are difficult to separate by external characters. The main difference is on the white patches of forewing. E. albidentata and E. arcuosa Chen & Wu , sp. nov. own a small crescent white patch at the outside of the apical yellow band of the forewing, while E. crenata Chen & Wu , sp. nov. is absent of such a patch (black arrow in Figs. 2a, 3a ). Moreover, the shape of the inner edge of the larger white patch is different in these species, which is strongly incurved in E. crenata Chen & Wu , sp. nov., smooth in E. arcuosa Chen & Wu , sp. nov. and intermediate in E. albidentata (white arrow in Figs 2a–4a ).

Differences in genital structures are quite obvious in these species. In male genitalia, E. albidentata can be differentiated by the basal half of the valval costa strongly sclerotized and the small and papilla-like transtilla. E. arcuosa Chen & Wu , sp. nov. can be separated by having a bifid transtilla, the sacculus without an apical harpe and the aedeagus with a branch at base. E. crenata Chen & Wu , sp. nov. can be distinguished by the broader valva, the valval costa not strongly sclerotized, and the slender and finger-like transtilla. In female genitalia, E. arcuosa Chen & Wu , sp. nov. and E. crenata Chen & Wu , sp. nov. can be distinguished by the presence of the signa.

© Zoological Systematics, 40(4): 470–475

Key to the species of Eugauria .

1. Forewing with a small white crescent patch at outside of apical yellow band (black arrow in Figs 2a, 3a ); inner edge of the inner and larger white patch smooth or slightly incurved (white arrow in Figs 2a–4a ). Male genitalia with sacculus broad........................2 Forewing without small crescent patch; inner edge of white patch strongly incurved. Male genitalia with sacculus narrow................ ......................................................................................................................................................... E. crenata Chen & Wu , sp. nov.

2. Forewing with inner edge of the inner and larger white patch slightly incurved. In male genitalia, apex of uncus pointed, basal half of valval costa strongly sclerotized, transtilla papilla-like and aedeagus without branch................................................ E. albidentata Forewing with inner edge of the inner and larger white patch smooth. In male genitalia, apex of uncus rounded, valval costa weakly sclerotized, transtilla bifid and aedeagus with a sclerotized apical branch........................................ E. arcuosa Chen & Wu , sp. nov.

Figures

Fig. 1. Venation of E. arcuosa Chen & Wu, sp. nov.

Figs 2–4. Adults of Eugauria spp. (a. enlargement of forewing). 2. E. albidentata. 3. E. arcuosa Chen & Wu, sp. nov., holotype, ♂. 4. E. crenata Chen & Wu, sp. nov., holotype, ♂.