Discovery of the larger grain borer in a tropical deciduous forest in Mexico

AbstractWe report on the first records of natural host plant utilization by Prostephanus truncatus. Spondias purpurea (‘ciruelo’) and Bursera fagaroides (‘cuajiote amarillo’) branches cut down by Oncideres albomarginata chamela were colonized by P. truncatus in the tropical deciduous forest of the Pacific Coast of México. An average of 328 P. truncatus individuals were captured in pheromone traps and 48 adults in direct samplings of S. purpurea twigs. Five host tree records collected previously are mentioned, all were recorded in the dry season. Strong preferences for cacahuazintle maize were detected by P. truncatus from S. purpurea twigs under laboratory conditions. All beetles had moved to the grain in 19 days. No P. truncatus were observed in either maize fields or rural storage houses of the region, only Sitophilus zeamais was detected, while the pheromone traps in the forest were capturing P. truncatus. Populations of P. truncatus are considered to be utilizing the natural vegetation as possible dissemination points for colonizing neighboring agricultural fields as food sources to which they were suited by chance.