|
SUBFAMILY
PANTHEINAE |
|
Arcte coerula Guenée (Plate 1, Figs 14, 15) Cocytodes coerula Guenée, 1852, Hist. nat. Insectes, Spec. gén. Lépid. 7: 42. Diagnosis. See the generic account and the previous species. The most distinctive feature is the double, bright blue but broken banding of the hindwing. Geographical range. Korea, Japan, China. Mainland Oriental tropics, Borneo, Philippines, New Guinea, Queensland, Norfolk I., Vanuatu, New Caledonia, Fiji, Samoa. Habitat preference. Only a single Bornean specimen has been seen, from 1465m on Bukit Retak, Brunei, where it was taken at light. The species may well be genuinely rare in Sundaland as it was not recorded from Sumatra by Kobes (1985) or from Peninsular Malaysia by Barlow (unpublished checklist for Genting Tea Estate). However, it is never abundant at light (e.g. Robinson, 1975; Holloway, 1979), and may respond only weakly in this way as it has apparently been overlooked on Norfolk I. through a light‑trapping survey over 12 years that yielded a sample of about a quarter of a million specimens (Holloway, 1996). Biology. The larva of coerula has been described by Gardner (1948a) and Robinson (1975), and was illustrated by Hampson (1893) and Sugi (1987). All prolegs are well developed. The head and body from the spiracles upwards are black, divided from the black ventral part by a strong but irregular longitudinal pale yellow band. The anal segments and broad areas around each spiracle are orange-red. The area across the back at A8 is broadly black, but segments anterior to this each have three transverse white bars that are centred by a black line. The area on each side between these bars and the spiracles is black apart from a line of bluish white dots just above the spiracles. The primary setae are long and conspicuously white. Robinson (1975) noted that the larvae often occurred in numbers in bushes of their host plants and, on being alarmed, would rear up on the posterior two pairs of abdominal prolegs and the anal ones and thrash from side to side, shaking the plant in a ‘most eerie fashion’. These larvae were observed in Vanuatu and appear to be more extensively black with only the red areas described above present; the ventral part was pale orange. Gardner (1948a) indicated that larval patterning was variable, particularly in the extent of the white markings, though the illustrations in Hampson (1893) and Sugi (1987) are similar in having these well developed. The host plants recorded (Robinson et al., 2001) are mostly in the Urticaceae: Boehmeria (recorded also on Norfolk I. in 2009; M. Jowett, pers. comm.), Cypholophus, Debregeasia, Girardinia and Pipturus. The larva also feeds on Trema in the related Ulmaceae. The record of Vitis (Vitaceae) in Zhang (1994) may be of adult fruit feeding. |
Copyright © Southdene Sdn. Bhd. All rights reserved.