Streblid flies parasitizing cave bats in Carajás, Amazonia, with a new record for Brazil

ABSTRACT Streblid flies (Diptera: Streblidae) are hematophagous and highly specialized parasitic insects, found only on bats (Chiroptera). Caves are important roosts for bats but, despite harboring high bat richness, relatively few studies exist on the ecology and biology of streblid flies in cave environments, especially in Amazonia, the largest domain in northern Brazil, with >140 bat species and thousands of caves. To fill some of the gaps in the geographical distribution and interspecific relationships for streblid flies in the region, we sampled bats in six caves in Carajás National Forest, a protected area in Pará state (Brazil). Thirteen of the 14 streblid species found are new records for Carajás, with three new records for Pará state and two for the northern region of Brazil. Nycterophilia fairchildi was recorded for the first time in Brazil. Most streblids had host-specific behavior, however, N. fairchildi, Trichobius caecus, and T. johnsonae were less host-specific, parasitizing different Pteronotus bat species. The gregarious behavior of Pteronotus species and the spatial distribution of their colonies within the caves may be important factors in the flies’ exchange among congener hosts and deserve special attention in future studies. Furthermore, studies on ecological interaction networks between bats and their ectoparasitic flies in caves will be useful for a broader understanding of how this relationship is structured over time and space, as well as its impact on both bats and flies.摘要：蝠蝇科（Streblidae，双翅目Diptera）昆虫为吸血性高度特化的寄生昆虫，仅寄生于翼手目（Chiroptera）蝙蝠体表。洞穴是蝙蝠重要的栖息场所，尽管可承载丰富的蝙蝠类群，但针对洞穴环境中蝠蝇的生态学与生物学研究仍相对匮乏，尤其是在巴西北部面积最大的亚马逊生态区——该区域拥有超过140种蝙蝠与数千处洞穴。为填补该区域蝠蝇地理分布与种间关系研究的部分空白，我们在巴西帕拉州一处保护区——卡拉贾斯国家森林公园的6处洞穴中开展了蝙蝠采样工作。本次调查共发现14种蝠蝇，其中13种为卡拉贾斯地区新记录种，3种为帕拉州新记录种，2种为巴西北部地区新记录种；费氏夜蝇（Nycterophilia fairchildi）为巴西境内首次记录。多数蝠蝇具有宿主专一性，但费氏夜蝇、盲毛蝇（Trichobius caecus）与约翰逊毛蝇（T. johnsonae）的宿主特异性较弱，可寄生于不同的叶口蝠属（Pteronotus）蝙蝠物种。叶口蝠属物种的群居习性及其集群在洞穴内的空间分布，可能是蝠蝇在同属宿主间传播的重要影响因素，该方向值得在后续研究中重点关注。此外，针对洞穴内蝙蝠与其体外寄生蝇类的生态互作网络开展研究，将有助于更全面地理解该种互作关系在时间与空间维度上的构建模式，及其对蝙蝠与蝇类双方的影响。