Mythimna (Hyphilare) hamifera Walker

Leucania exsanguis Guenee, 1852, Hist. nat. Insectes. Spec. gen. Lepid. 5:82.

Leucania hamifera Walker, 1862, J. Linn. Soc. Lond. (Zool.) 6: 179, syn. n.

Leucania subnitens Swinhoe, 1890, Trans. ent. Soc. Lond. , 1890: 218 syn. n.

Cirphis subdecora Wileman, 1912, Entomologist 45: 147.

Diagnosis

The species has the wings silvered below as in decississima Walker and, to a lesser extent, calorai sp. n.; all three species have a black tuft of hair-like scales at the base of the abdomen below. It is most similar to calorai, having greyish rather uniform forewings; decississima has the forewings straw colour, marked with brown, the brown particularly intense around a longitudinal pale streak in the cell. In the male genitalia the harpe from the sacculus is shorter than in the next two species and not curved; the neck of the cucullus is longer than in Mythimna decisissima Walker, and the cucullus itself distinctly asymmetrical. The aedeagus vesica lacks lateral lobes and has a terminal group of long cornuti, one much thicker than the rest.

Taxonomic notes

• The taxa exsanguis and hamifera were regarded as distinct by Calora (1966), but it was not possible to confirm the differences he observed. The taxa are therefore brought into synonymy.
• Hacker et al. (2002) listed M. hamifera Walker as distinct from M. exsanguis Guenée, following Yoshimatsu (1995b), rather than as a synonym as in Part 12. The type locality of the former is Borneo, so this must be one taxon of the pair that occurs there. Yoshimatsu (1994) still listed hamifera as a synonym of exsanguis and did not mention the taxon in his paper on Bornean Mythimna (Yoshimatsu 1995a). Yoshimatsu (1995b) supported the assertion made in Part 12 that the male genitalia of hamifera and exsanguis were almost identical except the vesica in hamifera is slightly longer. However, he recorded a greater distinction in the female genitalia where the ductus seminalis arises more left‐laterally from a distinct diverticulum on the appendix bursae in hamifera rather than more dorsally from a slight bulge as in exsanguis. Externally, hamifera can usually be distinguished by a prominent white streak running longitudinally through the discal zone of the forewing that is absent from exsanguis. Calora (1966) stated that exsanguis had a much more uniform forewing generally, but this applies only in the Philippines where this distinction forms the basis for the separation of exsanguis ssp. hiraii Yoshimatsu (1995b). It is still unclear whether exsanguis occurs in Borneo, but it is likely. However, the species is not listed here in the absence of a definite record; the male illustrated in Part 12 is too worn for firm assessment of the forewing facies character (Yoshimatsu, 1995b). Yoshimatsu placed the taxa inframicans Hampson and pryeri Leech as synonyms of hamifera, and listed subnitens Swinhoe and subdecora Wileman as synonym of exsanguis.

Geographical range

Indian Subregion to Taiwan, Sundaland, Philippines and Sulawesi.

Habitat preference

No material has been taken in recent surveys. Bornean material seen is mainly from lowland localities.

Biology

Piepers & Snellen (1906) described the Javan larva. It is smooth, mottled yellowish-grey with a median line and several others in a paler colour. The intersegmental region is reddish. The host-plant recorded was Saccharum

Genitalia: