Exoasota Ko & Bae, 2020

Ko, Jae-Ho, Bayarsaikhan, Ulziijargal, Park, Bo-Sun, Lee, Tak-Gi, Cha, Yeong-Bin, Jang, Chang-Moon, Lee, Jong Koo & Bae, Yang-Seop, 2020, Exoasota pursatensis Ko & Bae, new genus and species of the Spilomelinae (Lepidoptera: Pyraloidea: Crambidae) from Indochina, Zootaxa 4838 (1), pp. 119-127 : 120-121

Genus Exoasota Ko & Bae , gen. nov.

TS: Exoasota pursatensis Ko & Bae , sp. nov. Gender: feminine.

Diagnosis. The new genus is morphologically similar to Epiparbattia Caradja, 1925 ( Crambidae , Pyraustinae ), but it can be distinguished from the latter by the following characters: patagium with two black orbicular spots; tegula with two black orbicular spots at middle; costal margin of forewing brown or light brown; basal area of forewing yellow, with two black orbicular spots; dorsum of forewing brown; discal cell of hindwing with a brown orbicular patch; fringe of hindwing brown; abdomen with symmetrical black, dorsal orbicular spots in each segments; in male genitalia, uncus long and pointed; valva ovoid; fibula spine-shaped, curved downwardly; juxta oblong; succus Vshaped; in female genitalia, antrum oblong, strongly sclerotized; corpus bursae cylindrical, without signum. Also, this genus is very similar to Asota Hübner, [1819] ( Erebidae , Aganainae ) superficially, but it can be distinguished from Asota by the following characters: vertex with a black patch; patagium and tegula with two black orbicular spots; basal area of forewing with two black orbicular spots.

Description. Head covered with yellow scales; antennae filiform; ocellus well-developed; chaetosemata absent; labial palpus upturned; maxillary palpus minute; proboscis well-developed ( Fig. 1 ). Thorax vivid yellow. Forewing rather rhomboid and with discal spots; costal margin nearly straight; apex pointed; termen somewhat arched; dorsum straight; frenulum hook absent; female with two frenular bristles. Hindwing fan-shaped, with discal spot, postmedian fascia and adterminal line or series of patches; costal margin rather straight; termen and dorsum rounded ( Figs. 4−7 ). Venation ( Fig. 3 ): forewing with 13 veins: Sc free; R 1 and R 2 free; R 3 and R 4 stalked for most of length; R 2 and R 3 +R 4 approximated; R 5 free; M 1 free; M 2 and M 3 approximated at base, before lower angle of discal cell; M 3 and CuA 1 from lower angle of discal cell; 1A free; 2A forming complete loop; discal cell about 1/2 length of forewing. Hindwing with 10 veins: Sc+R 1 and Rs stalked for 2/3 length of Rs; M 1 from upper angle of discal cell; M 1 and M 2 from lower angle of discal cell; CuA 1 and CuA 2 stalked for 2/5 length of CuA 2; 1A, 2A and 3A free; discal cell about 1/3 length of hindwing. Abdomen covered with yellow scales and symmetrical black orbicular spots ( Figs. 4−7 ). Tympanal organs well˗developed, broadly rounded, deeply concave; fornix tympani projecting in ventral direction; tympanum and conjunctivum angled; praecinctorium strongly bilobed ( Figs. 2 , 12 ). In male genitalia, uncus slender, sharpened, and setose at apex; valva oval-shaped, sclerotized at costal margin; fibula strongly sclerotized, spine-shaped; sacculus sclerotized; juxta oblong; saccus V-shaped; aedeagus cylindrical, cornuti present ( Fig. 11 ). In female genitalia, apophyses anterior and posterior short; ostium tube-shaped, sclerotized; ductus bursae narrow, membranous; corpus bursae ovoid and signum absent ( Fig. 13 ).

Distribution. Cambodia, Myanmar, Thailand, Vietnam.

Etymology. The generic name is a combination of the prefix Exo, derived from the Greek for “outside”, and the suffix Asota in reference to the genus Asota (Erebidae) , from where species are very similar in the wing pattern. Gender is feminine.

Figures

FIGURE 3. Wing venation of Exoasota pursatensis sp. nov.

FIGURES 1−2. 1. Lateral view of head of Exoasota pursatensis sp. nov. 2. Tympanal organs of Exoasota pursatensis sp. nov.

FIGURES 4−10. Adults of new and compared species from Indochina. 4. Exoasota pursatensis sp. nov., male (holotype, INU−6575 Cambodia). 5. ditto, female (paratype, INU−6576 Cambodia). 6. ditto, male (paratype, INU−6556 Vietnam). 7. ditto, female (paratype, INU−6554 Myanmar). 8. Asota tortousa, male, Myanmar. 9. ditto, female, Myanmar. 10. Epiparbattia gloriosalis, male, Myanmar.

FIGURES 11−13. Genitalia and tympanal organ of Exoasota pursatensis sp. nov. 11. Male genitalia (holotype, INU−6575 Cambodia). 12. Tympanal organ (paratype, INU−6513 Cambodia). 13. Female genitalia (paratype, INU−6576 Cambodia).