First report on dung beetles in intra-Amazonian savannahs in Roraima, Brazil

This is the first study to address the dung beetle (Coleoptera: Scarabaeidae: Scarabaeinae) diversity in intra-Amazonian savannahs in the state of Roraima, Brazil. Our aim was to survey the dung beetle fauna associated with these savannahs (regionally called 'lavrado'), since little is known about the dung beetles from this environment. We conducted three field samples using pitfall traps baited with human dung in savannah areas near the city of Boa Vista during the rainy seasons of 1996, 1997, and 2008. We collected 383 individuals from ten species, wherein six have no previous record in intra-Amazonian savannahs. The most abundant species were Ontherus appendiculatus (Mannerheim, 1829), Canthidium aff. humerale (Germar, 1813), Dichotomius nisus (Olivier, 1789), and Pseudocanthon aff. xanthurus (Blanchard, 1846). We believe that knowing the dung beetles diversity associated with the intra-Amazonian savannahs is ideal for understanding the occurrence and distribution of these organisms in a highly threatened environment, it thus being the first step towards conservation strategy development.

本研究为首个针对巴西罗赖马州亚马孙内陆稀树草原内蜣螂（dung beetle）多样性开展的调查，所涉类群隶属于鞘翅目（Coleoptera）金龟科（Scarabaeidae）粪金龟亚科（Scarabaeinae）。鉴于当前对该生境下蜣螂类群的认知极为匮乏，本研究旨在调查与这类稀树草原（当地称"lavrado"）相关联的蜣螂动物区系。我们于1996年、1997年及2008年的雨季，在博阿维斯塔市附近的稀树草原区域布设以人粪为诱饵的陷阱诱捕器，完成了三次野外采样。本次调查共采集到383头个体，隶属于10个物种，其中6个物种此前在亚马孙内陆稀树草原中无分布记录。物种丰富度最高的类群包括具毛厚蜣螂（Ontherus appendiculatus, Mannerheim, 1829）、近肩蜉金龟（Canthidium aff. humerale, Germar, 1813）、尼氏叉蜣螂（Dichotomius nisus, Olivier, 1789）以及近黄伪蜉金龟（Pseudocanthon aff. xanthurus, Blanchard, 1846）。我们认为，探明亚马孙内陆稀树草原相关联的蜣螂多样性，有助于理解这类生物在受高度威胁的生境中的发生与分布规律，同时也可为后续保护策略的制定奠定首要基础。