Number: 185
Family: Hesperiidae
Sub-Family : Hesperiinae
Species: Koruthaialos rubecula hector Watson, 1893
Common name(s): The Narrow-banded Velvet Bob
Photography location: Cat Ba National Park (Hai Phong City)
The genus
Koruthaialos comprises of 4 species, all of which being limited to the Oriental region. In Vietnam 3 are recorded -
rubecula,
sindu and
butleri.
Butleri is unique for the genus in having no oblique orange band on forewing.
Tonkin and S. Annam, respectively, are the type-localities of gopaka Frühst, and avidha Frühst., both synonyms of hector. The subspecific division of rubecula is rather complicated by its individual and seasonal variability and, in particular, by the existence of bandless specimens found occasionally throughout the species range (Evans, 1949)
This species is very closely related to K.sindu. But in sindu the orange band is wider, almost of equal width throughout, and extends as far as the leading edge of the forewings
Moreover the third segment of palpi is short and stout in sindu, long and slender in rubecula