16-17mm. The antennae are not noded and the labial palps are more forward-directed as in Paracolax, but the facies is closest to that of Hadennia. The subcostal flap is more obviously associated with a fold or groove in the forewing. The ground colour of the wings is medium grey, but there is a band of black contiguous from hind- to forewing, oblique on the latter and truncated over the costal half of the former, that is defined distally by a pale submarginal as in maculifascia and grades away basad into the grey ground. The exterior border of this band on the forewing is diagnostically lobed just anterior to its centre. The discal mark is a pale dash that is largely obscured by a suffusion of black that just reaches the major black band. The forewing has a much narrower, obscure, straight antemedial, just basal to a black orbicular dot. The underside is a uniform brownish grey except for punctate white submarginals, that of the hindwing stronger than that of the forewing. The male genitalia are atypical of both Paracolax and Hadennia, lacking the structure between the valve bases, the valves themselves having no saccular process, but with a large, curved central process and a subapical rugose lobe on the costal margin. The aedeagus has a slightly spined projection apically, and the vesica has more slender diverticula than in other Hadennia, the more distal one with two unequally long, slender cornuti.
Holotype. SARAWAK: Gunong Mulu Nat. Park, R.G.S. Exped. 1977-8 (J.D. Holloway et al.), Site 13, February, Camp 2, Mulu, 500m, 401464, mixed dipt. for., BM noctuid slide 19393.
Paratypes: 1 as holotype; 1 general data as holotype but Site 10, February, Camp 1, Mulu, 160m. 386470, mixed dipt. for.; 1 BRUNEI: 60m, Ulu Belait, lowland forest, 20.2.80 (Lt. Col. M.G. Allen); 1 BRUNEI: 30-60m, Labi, lowland forest and secondary veg., 12.4.81 (Lt. Col. M.G. Allen); 1 MALAYSIA: Sabah, Danum Valley, 170m, 4°58'N 117°48'E (S.J. Willott) 1° understorey, W5, West Trail, DVFC, 5.viii.94; 1 as previous but 1° understorey, W9, West Trail, DVFC, 01.iii.94.
Geographical range. Borneo.
Habitat preference. All material is from lowland forest, the highest record being from 500m in hill dipterocarp forest. The material recorded at the Danum locality (six specimens; Willott, unpublished) was all taken in the understorey.
