Preliminary observations on a skin-piercing blood-sucking moth (Calyptra eustrigata (Hmps.) (Lep., Noctuidae)) in Malaya

Abstract

In the course of entomological investigations in Malaya between 1965 and 1967, it was found that Calyptra eustrigata (Hmps.) (Noctuidae) frequently pierces the skin of mammals to feed on blood, and in this respect differs from those Noctuids that marely imbibe blood from an open wound. Other species of Calyptra are known as fruit-piercing moths, and C. minuticornis (Gn.) which was taken in Cambodia on one occasion at the eye of a buffalo, is also one of the eye-frequenting moths, which imbibe lachrymal secretions of Ungulata, Proboscidea and occasionally of man. C. eustrigata has been observed imbibing blood after piercing the skin of buffalo, Sambar deer, Malayan tapir and nilgai antelope. Caged adults in the laboratory were observed piercing the skin of human fingers offered to them; and imbibition of blood continued for up to and hour. The proboscis, which ends in a sclerotised and strongly barbed point, can penetrate about six millimetres below the surface. The two halves of the proboscis work like two paralled saws moving alternately. While feeding is in progress, droplets of saliva exude at the base of the probiscis and run down the outside. Often some blood is regurgitated, then reabsorbed. The puncture causes itching, which can last for up to an hour, and local hardening of the tissue, which can persist for five weeks. By reason of its mode of feeding, C. eustrigata would appear to be a potential vector of disease, as the saliva and regurgitated fluids might transmit pathogenic agents.