Systematics Monotypic. Relationship to other Hepialidae undetermined. Larvae lack prothoracic senstory pits and in this respect my be unique among the Hepialidae (Grehan & Rawlins, 2003).
Habitat Shrubland, Fynbos (Duke & Taylor, 1964).
Biology Given the large size and distinctiveness of this species it is perhaps surprising that the biology is not extensively documented. Larvae bore into the basal stem of keurboom, Virgillia oroboides. Adults emerge in the evening from 6.45 pm or later and from late summer (February) and early autumn (March and possibly April) (Duke & Taylor, 1964). Recently (2016) observations have been made of Leto venus boring into farm cultivated Cyclopia subternata trees.
Prior to pupation the larvae constructs a tubular extenstion of the tunnel out of silk and frass that projectings beyond the trunk surface for severl centimeters. This tube appears to be a unique construction in the Hepialidae (Duke & Taylor, 1964; J.R. Grehan personal observation of specimens in the Peabody Museum, Yale)
References Duke, A.J. & J.S. Taylor. 1964. A note on Leto venus Stoll. (Lepidoptera: Hepialidae). The Entomologist's Record and Journal of Variation 76, 189-193. Grehan, J. R. and J. E. Rawlins. 2003.Larval description of the New World ghost moth Phassus and the evolutionary biogeography of wood boring Hepialidae (Lepidoptera: Exoporia: Hepialoidea). Journal of the Washington Entomological Society 105, 733-755. Janse, A.J.T. 1945. On the history and life-history of Leto venus Stoll. Journal of the Entomological Society of South Africa 8, 154-165.
Leto venus. Bergville, South Africa. February 2016. Photo by Colin Ralston, iSpot
Leto venus dorsal. Bergville, South Africa. February 2016. Photo by Colin Ralston, iSpot