Risoba thalasscura Holloway sp. n.
Diagnosis
♂ 16mm, ♀♀ 16-17mm.
This and R. harmani are very similar in facies, with blackish brown clouding on a rather pale emerald green ground. The clouding is stronger in thalasscura such that the unclouded roughly triangular area medially at the costa is more conspicuous. The hindwing has a more distinct discal lunule on the upperside than the next. Both differ from preceding members of the jucunda group in having more robust genitalia with shorter valves and a more distinctive costal flange. This is somewhat trapezoid in thalasscura and set opposite a concavity in the costal margin that is bounded distally by a slight protrusion. The aedeagus lacks conspicuous spines, and the vesica has a narrow diverticulum tipped with fine spicules as in jucunda.
Holotype ♂
BRUNEI: 30-60m, Labi, lowland forest, 20.8.1979 (Lt. Col. M.G. Allen), BM noctuid slide 16687.
Paratypes
- 1♀ BRUNEI: 300m, Ulu Temburong, rainforest, 25.9.78 (Lt. Col. M.G. Allen)
- 1♀ Retak, LP 238, 1465 metres, BRUNEI, 23.iv.1981 (T.W. Harman)
- 1♀ S.E. BORNEO: Samarinda, x.1938 (M.E. Walsh)
- 1♀ SABAH: Telupid, 9-22 Sept 1987, Coll FRC, Sepilok.
Geographical range
Borneo.
Habitat preference
Four of the specimens are from the lowlands but one is from 1465m in montane forest.
Genitalia:
