Salomão R P, Maia A C D, Bezerra B M, Iannuzzi L
Instituto de Ecología, A. C., Red de Ecoetología, 91070, Xalapa, VER, Mexico.
Programa de Pós-Graduação em Biologia Animal, Univ Federal de Pernambuco, Recife, PE, Brazil.
Neotrop Entomol. 2018 Feb;47(1):69-78. doi: 10.1007/s13744-017-0515-1. Epub 2017 Apr 11.
Excrement scarcity is one of the main historical factors leading dung beetles to adapt to other food resources. In the Caatinga, a seasonally tropical dry forest, harsh environmental conditions seem to restrict the availability of food resources. In this scenario, the aim of our study was to experimentally investigate the attractiveness of different potential food resources to these insects in the Caatinga. Field samplings were performed, and we tested five resources in pitfall baited traps: excrement, carrion, fruits of two species of columnar cacti, and seeds of one species of Euphorbiaceae (Jatropha mollissima (Pohl)). In a controlled setting, we tested dietary preferences of Deltochilum verruciferum Felsche by offering one or two resources simultaneously. In the field experiments, 297 dung beetles (9 species) were recovered from the traps, and D. verruciferum was the most abundant species. Carrion and excrement were the most attractive resources. Controlled dietary preference tests with D. verruciferum evidenced that these beetles used all tested food resources, excrement and carrion most pronouncedly. Our findings support copro-necrophagy as the main feeding habit of D. verruciferum, but also suggest that alternative resources might be utilized if preferred resources are scarce.
粪便稀缺是导致蜣螂适应其他食物资源的主要历史因素之一。在卡廷加（Caatinga），一个季节性热带干旱森林中，恶劣的环境条件似乎限制了食物资源的可用性。在这种情况下，我们研究的目的是通过实验调查卡廷加地区不同潜在食物资源对这些昆虫的吸引力。我们进行了实地采样，并在陷阱诱捕器中测试了五种资源：粪便、腐肉、两种柱状仙人掌的果实以及一种大戟科植物（麻疯树（Jatropha mollissima (Pohl)））的种子。在可控环境中，我们通过同时提供一种或两种资源来测试疣纹粪金龟（Deltochilum verruciferum Felsche）的饮食偏好。在野外实验中，从陷阱中捕获了297只蜣螂（9个物种），疣纹粪金龟是最丰富的物种。腐肉和粪便是最具吸引力的资源。对疣纹粪金龟进行的可控饮食偏好测试表明，这些甲虫会利用所有测试的食物资源，对粪便和腐肉的利用最为明显。我们的研究结果支持粪腐食性是疣纹粪金龟的主要摄食习性，但也表明，如果首选资源稀缺，它们可能会利用其他替代资源。
