Rediscovery of the ‘extinct’ bee Hesperocolletes douglasi Michener, 1965 (Colletidae: Colletinae: Paracolletini) in Western Australia and first description of the female

Abstract

The second known specimen of the bee Hesperocolletes douglasi Michener, 1965 is here reported as a serendipitous find among a collection of insect pollinators from an isolated woodland remnant in the Southwest Floristic Region of Western Australia. The unique male holotype of this monotypic genus of bees was collected 80 years ago and officially gazetted as presumed extinct in 1994. With our collection of a female specimen in 2015, however, it now appears that H. douglasi may persist as an extant localised population. Follow-up efforts to find more specimens at the collection locality so far proved unsuccessful, indicating that the species is likely either very rare or inhabits an ecological niche that is yet to be discovered. Analysis of the pollen load carried by the female indicates that the species may be polylectic. We discuss the context of the rediscovery of the bee, provide a detailed description and illustrations of the female, and make observations about the unusual morphological characteristics of the species. The rediscovery of H. douglasi emphasizes the importance of conservation efforts for remnant woodlands in the region, both as potential habitat for the bee and as remaining habitat essential for other rare and threatened species in this global biodiversity hotspot.

Keywords

• banksia woodlands
• douglas’s broad-headed bee
• global biodiversity hotspot
• hesperocolletes, pollinator
• rediscovery
• southwest australian floristic region
• threatened species