Gyrtona eusema Prout comb. n.stat. n.
Nigramma quadratifera eusema Prout, 1926, Sarawak Mus. J. 3: 225.
Nigramma quadratifera eusema Prout; Holloway, 1976: 20, fig. 125.
Diagnosis
The species is similar in facies to pseudoquadratifera but very much larger and with a diffuse dark bar from the costa to the reniform.
The main distinguishing feature in the male genitalia is the very long and slender harpe.
Taxonomic Notes
This and the previous two species all resemble quadratifera but none are clearly conspecific.
Therefore eusema is here raised to specific status.
Geographical range
Borneo.
Habitat preference
The holotype is from G. Murud in Sarawak and a further specimen was taken in upper montane forest on G. Mulu.
Several were taken at 1930m and 2110m on G. Kinabalu.
The species thus appears restricted to upper montane forest.
Genitalia: