Genus Orgyia

Vaporer, Vaporer Moth, Vapourer Moth

Orgyia Ochsenheimer, 1810

From Greek orgyia (οργυια, from ορεγειν stretch out) meaning "the length of the outstretched arms", a fathom (1) (2), referring to the insect's habit of extending the forelegs. (3)

Another name used for the adult moths is "vaporers" or "vaporer moths" for the "vaporing" flight pattern (2).

930160 Orgyia antiqua (Linnaeus, 1758)

930161 Orgyia vetusta Boisduval, 1852

930162 Orgyia magna Ferguson, 1977

930163 Orgyia cana H. Edwards, 1881

930164 Orgyia pseudotsugata (McDunnough, 1921)

930165 Orgyia detrita Guérin, 1831

930166 Orgyia definita Packard, 1864

930167 Orgyia leuschneri Riotte, 1972

930168 Orgyia leucostigma (J.E. Smith, 1797)

930169 Orgyia falcata Schaus, 1896

Here are some examples of the females in this genus: --

Marc Bélisle found interesting references concerning the mode of reproduction of certain species of the genus Orgyia. This information seems to corroborate the hypothesis of such a cocoon. Here are those references:

"Adults emerge from mid-April to early May. The flightless females remain on their cocoons and release a sex pheromone to attract males. The sex pheromones of Orgyia detrita and Orgyia leucostigma have been characterized (Grant et al. 2003, Gries et al. 2003).

After mating, the females lay a mass of eggs directly on the cocoon and cover them with a protective covering. Detrita and definita females cover their eggs with a secretion and then rub setae from their bodies onto the secretion to form a protective layer over the eggs. Leucostigma females cover their eggs with a frothy secretion but do not cover the secretion with setae (Ferguson 1978). The egg stage is the overwintering stage for all three species.

Voir Fig. 20-23 : http://entnemdept.ufl.edu/creatures/urban/medical/tussock_moths.htm

… Alain Hogue, 21 February, 2021