Notes on Biology and Behavior of Rhinoceros Beetle Enema pan (Coleoptera: Scarabaeidae: Dynastinae)

Abstract

Abstract Dynastinae beetles (Coleoptera: Scarabaeidae) are important due to their role in recycling plant material and promoting nutrient turnover. However, some species are phytophagous and can attack crop plants, thus becoming pests. Here, we provide information on the biology and behavior of the rhinoceros beetle Enema pan (F.) (Oryctini), an abundant species in the area of Cerrado-Pantanal ecotone, Aquidauana, Mato Grosso do Sul, Brazil. Adults were collected with a light trap deployed daily from January 2006 to December 2007 in the experimental farm of the Universidade Estadual de Mato Grosso do Sul (Aquidauana campus). Adults were maintained in plastic containers and observations were made daily. Temporal distribution of adults of E. pan occurred in September and October (2006) and from October to December (2007). Flight started at 1930 hours and ended at 2330 hours. Twenty-four eggs (3.28 mm in length by 2.32 mm in width) with a whitish color were ovipositioned directly in to the soil. Adult longevity averaged 22.0 d in the laboratory conditions. Cephalic horn length, body length, and width of E. pan males are greater than those of females. The weight of adults of both sexes was similar. Cephalic horn length of the males of E. pan was positively correlated with his body size. Mating occurred between 0800 and 1030 hours and lasted on average 18.1 min in the laboratory. Several fights among males and other behaviors involving males and females were observed and are reported.