Crocidosema aporema (Walsingham) (Tortricidae: Olethreutinae: Eucosmini)
Common names: bean shoot moth
Synonyms: opposita (Epinotia)
Note: The name Crocidosema aporema is currently used for at least three different species. "True" C. aporema is from Costa Rica and is likely not a significant pest. The major pest species is likely undescribed. Future taxonomic work is badly needed to clarify this problem. Much of the information below regarding the pest species likely applies to an undescribed species, but we retain the use of the name "C. aporema" here because of its wide use in literature.
FWL: 6.5–8.0 mm
Adults are sexually dimorphic. The male forewing is mostly brown to reddish brown with a pale dorsum and large costal patch. The female forewing is mostly pale with a dark patch on the dorsum. Males have several secondary sexual structures including a forewing costal fold and black scaling on the hindwing.
Male genitalia are characterized by a short triangular uncus, large triangular socii, and a parallel-sided cucullus. Female genitalia are characterized by a pair of rounded pockets on sternum VII and a large rounded corpus bursae with two signa.
The following account is summarized from MacKay (1959)MacKay (1959):
MacKay, M. R. 1959. Larvae of the North American Olethreutidae (Lepidoptera). Canadian Entomologist, Supplement 10: 1-338. and Morey (1972)Morey (1972):
Morey, C. S. 1972. Biologiacute;a y morfologiacute;a larval de Epinotia aporema (Wals.) (Lepidoptera, Olethreutidae). Univ. Rep. Fae. Agron. Montevideo Bol. 123: 1-14..
Mature larva approximately 10–12 mm in length; width of head 0.9–1.0 mm; head yellow or yellowish brown with darker lateral pigmentation; prothoracic shield, legs yellowish; body yellowish green; anal fork present, moderately developed; SV group on A1, 2, 7, 8, 9 typically 3:3:2:2:2.
Detailed figures of larval chaetotaxy are available in MacKay (1959)MacKay (1959):
MacKay, M. R. 1959. Larvae of the North American Olethreutidae (Lepidoptera). Canadian Entomologist, Supplement 10: 1-338.. See the species page on LepIntercept for more details.
Other species of Crocidosema, including the cosmopolitan species C. plebejana and C. lantana, may appear similar. Most individuals of C. plebejana have a distinctive white ocellus and white patch on the dorsum of the forewing. The male cucullus is enlarged and subtriangular, and the pockets on the female sternum VII are developed into two lobes or "flaps" in C. plebejana. C. lantana is also very similar and may require a genital dissection for identification.
Larval damage on beans is similar to that caused by Ecdytolopha fabivora; however, larvae of C. aporema feed primarily on young leaflets while those of E. fabivora feed in the stems and pods. An anal comb is present in C. aporema but is absent in E. fabivora.
Other bean-feeding tortricids in South and Central America include Amorbia spp., Cydia torostoma, Lusterala phaseolana, and Platynota spp.
Crocidosema aporema is distributed from Central and South America south to Argentina and Chile. It was reported from South Texas in the 1940s but has not been reported causing economic damage in the United States.
The following account is summarized from Bentancourt and Scatoni (2006)Bentancourt and Scatoni (2006):
Bentancourt, C. M., Scatoni, I. B. 2006. Lepidoacute;pteros de importancia econoacute;mica. Reconocimiento, biologiacute;a y dantilde;os de las plagas agriacute;colas y forestales. Montevideo, Agropecuaria Hemiferio Sur SRL. 437 pp..
Crocidosema aporema completes 4–6 generations per year, with at least two generations occurring on soybean. Adults can be present year-round and are most common between April and November in South America.
Females lay eggs on glabrous nodes of the soybean plant (Glycine max) or other leguminous host. Early instar larvae feed primarily on terminal buds, folding or rolling the young leaflets. Later instars may tunnel into stems, floral buds, and pods. Pupation occurs in the soil or in rolled leaves.
Larval feeding leads to reduced plant height, drying of terminal shoots, a decrease in lower pod insertion, and damage to flowers, all of which can result in reduced yields in soybean and other crops.
Crocidosema aporema is a major pest of soybean and cultivated beans (Phaseolus spp.) in Central and South America. While larvae feed primarily on Fabaceae, they have also been recorded on cotton (Gossypium sp.) and corn (Zea mays).
View full screen host table here
Authors: KA Austin, TM Gilligan, ME Epstein
Content last updated May 2025
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