Megacerus species (Coleoptera: Bruchidae) and their host plants in Yucatán

Abstract

Seed-attacking by Megacerus (Coleoptera: Bruchidae) is reported for 7 Convolvulaceae species from 6 sites at the North of Yucatan. Seeds of Ipomoea crinicalyx, I. hederifolia, I. nil, I. triloba, Jacquemontia penthanta, Merremia aegyptia and M. cissoides were collected and placed in clean envelopes under laboratory conditions to collect all bruchids emerged from seeds. A total of 1111 coleopterans were hatched from seeds, and 5 taxa were identify: Megacerus (Megacerus) cubiculus, M. (M.) porosus, Megacerus (M.) sp., M. (M.) tricolor, and M. (Serratibruchus) cubiciformis. Seeds of I. crinicalyx, M. aegyptia and M. cissoides were attacked mainly by M. (M.) porosus; I. hederifolia and I. triloba ones by M. (M.) cubiculus, and I. nil ones by M. (M.) tricolor. Individuals of Megacerus (M.) sp., hatched exclusively from J. penthanta seeds. At level of host plant gender, Ipomoea was overall attacked by M. (M.) cubiculus and Merremia was by M. (M.) porosus. Our results increase the number of host plants reported for Megacerus and suggest a close interaction between one lineage of Bruchidae and species of the Convolvulaceae family.