Hornet moth

Naming

*British Isles ''Sesia bembeciformis'' smaller with black head and shoulders.
⤷ Europe ''Eusphecia melanocephala'' Dalman 1816
⤷ Europe ''Eusphecia pimplaeformis'' Oberthür 1872

Status

Populations of ''S. apiformis'' in the United Kingdom have shown evidence of decline over the past couple decades. While the adult forms are elusive and therefore have always been difficult to observe in the wild, the partially protruding pupae that are left after adult emergence provide a proxy for the number of moths in an ecosystem. In several sites around southern England where old exit holes were found, no new exit holes were found in trees, suggesting local population extinction. This coupled with the under-reporting of the species has led it to be classified as nationally scarce in the United Kingdom.

Habitat

Adult hornet moths are often found in open habitat such as parks, golf courses, and marshy areas. Females prefer to lay eggs on old or isolated trees, especially trees surrounded by vegetation.

Reproduction

''S. apiformis'' larvae hatch from September to May and spend two or three years in the larval stage, overwintering as larvae. The larvae are mostly found around the roots of host trees. Prior to pupating, the larvae bore up to ten centimeters into the trunk of the host tree leaving a thin layer of bark over the entrance to disguise the tunnel. Once inside the larva builds a cocoon from silk and excavated tree material.

Food

Larvae feed on host trees of several poplar species including ''Populus tremula'' and ''Populus nigra'' as well as ''Salix caprea''. The moth also prefers to feed around trees surrounded by heavy vegetation. It was found that trees near this heavy vegetation suffered from a lot more infestation than those without the basal vegetation.