Synonyms and other taxonomic changes
Utetheisa ornatrix (Linnaeus, 1758)
syn. Utetheisa bella (Linnaeus, 1758)
* phylogenetic sequence # 930348
Utetheisa ornatrix and Utetheisa bella were formerly considered separate species, now lumped together under U. ornatrix (See Moths of North America, below.)
Numbers
One species in the genus occurs in America north of Mexico.
(1)
Two subspecies in North America are no longer recognized.(1) Identification
adult forms:
Larva: orangish-brown with broad irregular black bands on each segment, and distinct white spots on anterior and posterior margins of black bands
Range
mostly Eastern North America: Nova Scotia to Florida, west to Arizona, north to Minnesota and Ontario
also occurs south through Central America to northern South America
Habitat
Fields, edges of forests; adults fly during the day
Season
adults fly from July to September in north; all year in south
Food
Larvae feed predominantly on legumes in the genus
Crotalaria, commonly called Rattlebox; occasional hosts included bush-clover (
Lespedeza spp.), elm, cherry, fireweed, lupine,
Sweetgale (
Myrica gale)
Crotalaria spectabilis(2) Life Cycle
Larvae feed on plants of the genus Crotalaria (family Fabaceae) which contain poisonous pyrrolizidine alkaloids, and are able to store the chemicals systemically, retaining them through metamorphosis into the adult stage. At mating, the male transfers a substantial fraction of his alkaloidal load to the female with the sperm package (spermatophore). The gift is transmitted by the female in part to the eggs, together with a supplement of her own alkaloidal supply. All developmental stages of Utetheisa are protected by the alkaloid, the larvae and adults against spiders, and the eggs are avoided by ants and coccinellid beetles. The spermatophore is of substantial size, amounting on average to over 10% of male body mass. It also contains nutrient, which the female invests in egg production. Females mate on average with four to five males over their lifespan of 3 to 4 weeks.
[adapted from text by Vikram Iyengar]
Life cycle images:
eggs; first instar larvae; older larva; older larva; pre-pupal larva; pupa; adult
Remarks
The mostly pink or yellow "bella" form is common and widespread, whereas the paler "ornatrix" form is restricted to southern Florida and southern Texas.
The courtship pheromones are enhanced because of pyrrolizidine alkaloids ingested by the larvae when eating
Crotalaria spectabilis. The alkaloids are retained into the adult stage and protect the next generation of eggs.
(2)Print References
Covell, p. 63, plate 15 #12
(3)
Lafontaine J. D., and B. C. Schmidt 2010. Annotated check list of the Noctuoidea (Insecta, Lepidoptera) of North America North of Mexico. p. 19.
(1)Internet References
Moth Photographers Group - range map, photos of living and pinned adults.
BOLD - Barcode of Life Data Systems - species account with collection map and photos of pinned adults.
PNAS scientific paper on mating and chemical protection
female mate selection issues (Vikram Iyengar, Villanova U., Pennsylvania)
