Working on Lasiocampidae at the moment

Grim news for fans of Trabala vishnou

I've checked in the two key books:
► Zolotuhin & Pinratana, 2005, Moths of Thailand 4: Lasiocampidae
► Liu & Wu, 2006, Fauna Sinica Insecta 47: Lasiocampidae
and find we have Trabala pallida for sure, and probably no T. vishnou.

male pallida is relatively small, and has the costal end of the medial fascia turning inwards, whereas in vishnou, the end of the fascia meets the costa pointing out to the apex.

females not so easy, but most pallida elsewhere appear to have an extra half fascia - the sub-basal is present on the dorsal half of the forewing, creating a "sub-basal eye spot" that is lacking in female vishnou.

The grim part is there are nearly 250 HK observations of Trabala on iNat, many of which are larvae. I have no idea how larvae of pallida and vishnou can be told apart, though the Taiwan subspecies of vishnou has far more yellow on the setae, and some continental vishnou (assuming correct id) have more yellow on the thorax and first abdominal segments. All the male HK Trabala are pallida, with the costally in-turned medial fascia. The three larvae I have reared to adult were all male pallida. They look the same as all the other HK Trabala larvae posted to iNat. It seems likely only pallida occurs here.

EDIT.... I've now been through Z&P 2005's live habitus photos, and there are illustrations of vishnou and pallida larvae. Larvae of vishnou have much more blue than the HK larvae; the illustration of pallida is very close to the HK larvae.