Abstract

The distribution of the rare Karst Snowfly, Allocapnia cunninghami Ross & Ricker, 1971, was assessed during winters of 2019 and 2020. This species has been assigned a NatureServe ranking of G1 (= Critically Imperiled) and was recently included in a Center for Biological Diversity petition to the U.S. Fish and Wildlife Service as potentially threatened or endangered. Sampling for adult A. cunninghami occurred in 45 unique localities in central Kentucky and middle Tennessee, USA, mainly within the known historical range of this species. This species was found in winters of 2019 and 2020 in very low numbers compared to regional Allocapnia and the winter-emergent fauna in general. Allocapnia cunninghami was collected at only five unique localities and comprised only 1.1% and 1.0% of all Allocapnia and the total winter-emergent fauna individuals collected, respectively. By comparison, the widespread species A. rickeri Frison, 1942 was collected from 41 of 45 unique localities and comprised 70% of all individual adults collected. Despite the difficulties of interpreting historical locality data from 1964 to 1966, A. cunninghami appears to now be present in fewer stream sites and distributed more patchily compared to ca. 55 years ago. A confounding biological factor for A. cunninghami is that Allocapnia adults in general have poor dispersal capacity, making natural colonization and potential recolonization events substantially more problematic for what appears to be a rare species in slow decline within an already small native geographic range.

Implications for insect conservation

By including positive collection data from 1999–2012, increasing the number of known contemporaneous sites to nine, predictive distributional models can now be generated to allow for more focused searching for previously undetected populations and potentially expand the known geographic range of this rare species.

中文翻译：

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1971年，东部罕见的近北喀斯特喀斯特雪蝇阿洛卡普尼亚杉木（Cunninghami Ross and Ricker）出现范围缩小和增加的种群分布斑块的证据

摘要

在2019年和2020年冬季评估了罕见的喀斯特雪蝇（Allocapnia cunninghami Ross＆Ricker）1971年的分布。该物种已被NatureServe评为G1级（=严重濒危），最近被纳入生物多样性中心。向美国鱼类和野生动物服务局（US Fish and Wildlife Service）提出的请愿书，因为它具有潜在的威胁或危险。在美国肯塔基州中部和田纳西州中部的45个独特地区进行了成虫A. cunninghami的采样，主要在该物种的已知历史范围内。与区域异地碳酸和一般冬季出现的动物相比，该物种在2019年和2020年的冬季发现的数量非常少。樟子松仅在五个独特的地方收集了该菌，分别仅占所有同素异能症和冬季收集的动物总数的1.1％和1.0％。相比之下，1942年的A. rickeri Frison物种是从45个独特的地区中收集到的，占所收集的所有成年个体的70％。尽管很难解释1964年至1966年的历史地点数据，但与ca.相比，坎宁哈米（A. cunninghami）现在似乎出现在较少的溪流地点，并且分布更为零散。55年前。对于混杂生物因素A. cunninghami是Allocapnia 一般而言，成虫的扩散能力差，使得自然定居和潜在的再定殖事件对于原本就很小的本地地理范围内缓慢下降的稀有物种而言，问题就更加严重了。

对昆虫保护的意义

通过包括1999-2012年的正收集数据，将已知同期地点的数量增加到9个，现在可以生成预测性分布模型，以便更集中地搜索以前未发现的种群，并有可能扩大该稀有物种的已知地理范围。