Bombyx incomposita van Eecke

Theophila incomposita van Eecke, 1929, Zool. Meded. Leiden, 12: 65.

Theophila religiosae Helfer, sensu Holloway, 1976: 85.

Diagnosis

The grey falcate forewings with a black apical zone and fine, evenly curved fasciae are distinctive.

Taxonomic Notes

Further dissection of Bombyx species has indicated that Sundanian material should be treated as distinct from Himalayan huttoni. The species is externally similar to huttoni, though specimens of the latter from the N.W. Himalaya have a double forewing postmedial, but the genitalia are relatively larger and more elongate.

In Java there flies B. horsfieldi Moore, with much more irregular fasciation.

It has recently been recorded from Taiwan (Kishida, 1984, Japan Heterocerist’s J., 127:23). In Sulawesi there is an undescribed species with both wings relatively much narrower, the hindwing tornus produced, acute.

Geographical range

Sumatra, Peninsular Malaysia, Borneo.

Habitat preference

The species is rare, taken in lowland rainforest in Brunei and at 1200m on G. Kinabalu.

Biology

Specimens of the larvae of the related T. huttoni are preserved blown in the BMNH. The thoracic segments are swollen almost into a sphere, and the abdomen is more or less cylindrical.

The skin is pale yellow with a variegated mottling of dark purplish brown.

This is weak over the thorax and in a broad dorsolateral band on each side of the abdomen so that there appear to be dark dorsal and lateral bands.

In the former each abdominal segment from 1 to 7 bears a pair of small, slender dark horns.

There is a single central larger one on A8 and a much smaller pair on A9. The eggs are laid on the twigs of the host-plant in large groups but not touching each other.

Genitalia: