Bulletin de la Société entomologique de France, 105 (2), 2000: 209-212.

A new subspecies of the genus Euthalia Hiibner, 1819, from Vietnam (Lepidoptera, Nymphalidae)

Exclusively asiatic, the genus Euthalia comprises four subgenera according to YOKOCHI (1999) : Euthalia, Bassarona, Dophla and Limbusa.

Euthalia iva belongs to the Limbusa subgenus and includes hitherto two subspecies : E. i. iva Moore, 1857, and E. i. cooperi Tytler, 1940. We describe here a third subspecies.

Euthalia (Limbusa) iva buensis n. ssp

(fig. 1)

Holotype : S , Central Vietnam, Nghe An province, Bu (=Pu) Huong Nature Reserve (19°15'-19°30'N, 104°45' -105°00'E), 900 m, 02.V.1995, collected by Frontier -Vietnam organization. Preserved in Muséum national d'Histoire naturelle à Paris (MNHN) (France). Paratypes : 1 â, Central Vietnam, Ha tinh province, Vu Quang Nature Reserve (18°09' -18°20°N, 105°16' -105°33'E), 1300 m, 06.VIII.1997, leg. A. Monastyrskii \ \S, North Vietnam, Lao Cai province, Hoang Lien Nature Reserve (22°09' -24'N; 103°47'-59'E), 1 450 m, 24.VIII.1998, leg. Vu Van Lien. Both males are preserved in MNHN.

Female unknown.

Upper side of forewing: the ground colour is dark greenish brown; two discocellular patches surrounded by black are very prominent; the white postdiscal band is well developed; there is an arrowhead-like white spot in space lb; the inner end of the spot in space 2 is remoted from the base of the space ; the white subapical spot in space 6 has a round shape, while the spot in space 7 is triangular.

Upperside of hind-wing : the ground colour is the same as forewing ; a discocellular patch is prominent ; the series of white postdiscal spots stretches from space 2 to 7 ; the spots in space 2 to 5 are rather clear and nearly equal ; the black submarginal fascia is rather prominent.

Underside of both wings : the ground colour is pale greenish blue with a more bluish tornal area of the hindwing; the posdiscal rows of white spots nearly same as on the upperside except for the appearance of a small dot-like spot in space lb on the hindwing; the subbasal irregular circular patches are very prominent on the hindwing.

Length of forewing : holotype 47 mm ; both paratypes 45 mm.

Genitalia S (fig. 3): the height of the tegumen is greater than that of the vinculum; the valves are strongly constricted between the saccular fold and the ventral lobe ; there are spicular teeth on the apex of the valves ; the gnathos is slender, with a weakly developed cochlear.

Discussion. -The type specimen used for comparison is: B. M. Type No Rh 1091 Adolias iva Moore, 6 , from Darjeeling (fig. 2). The drawing of genitalia 6 of the nominate