Temporal distributions of Conotrachelus and Anthonomus weevils (coleoptera: curculionidae) and Malpighia glabra fruit yields in El Trapiche, Mexico

The temporal and spatial distributions of Conotrachelus spp., primarily C. eburneus Champion, In an acerola, Malpighia glabra (L.), grove in Fl Trapic he, Mexico, were determined from 1995 to 1998, and compared with population s of Anthonomus sisyphus Clark, A. caracasius (Faust), and A. alboscutellat us Champion from 1997 to 1998. The temporal distributions of M. glabra frui ts were also determined from 1995 to 1998, and spatial distributions among blocks within the grove were determined from May to October 1998. Conotrach elus were found in highest numbers from June to November in all 4 years, co inciding with the rainy season. Anthonomus spp. were also most abundant fro m June to November in 1998. A. sisyphus and A. caracasius populations were distinctly bimodal, with peaks in July and November, after the second and t hird major fruit harvests. Few weevils of any species were present during t he first major fruit harvest. Correlations of temporal abundance from 1 Oct ober 1997 to ii December 1998 (176 dates) between Conotrachelus and A. sisy phus and A. caracasius were >0.500. Conotrachelus and Anthonomus were most abundant 3-3 weeks after peak fruiting times, and there were no correlation s between temporal distributions of any weevil species and fruit yields. Sp atial distributions among blocks within the M, glabra grove for Conotrachel us were always random in 1995 and 1996. Distributions for Anthonamus specie s were random most of the year, but A. caracasius and A. sisyphus distribut ions were slightly aggregated in May. In contrast, fruit distributions amon g blocks from May to October 1998 (after the peak fruiting period) were mor e aggregated. Because the temporal distributions of Conotrachelus and Antho nomus weevils were correlated (except with A. alboscutellatus), control mea sures against these weevils need to be conducted simultaneously or fairly c lose in time. Weevil distributions within the homogenous M. glabra grove we re generally random, suggesting a relatively small portion of such groves n eed to be sampled to generate representative population estimates, regardle ss of fruit aggregation. Factors that influence even slight aggregation ten dencies of Anthonomus weevils may be helpful in devising control methods.