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''Hesperocolletes douglasi'', the Rottnest bee, is an extinct species described from a single specimen collected in 1938. Body was black, shiny and 12 mm long and wings were brown and up to 8 mm long. Rottnest Island contains unique flora and fauna, such as ''Melaleuca lanceolata'' and ''Callistris preissii'', and was remote from human activities. The reduction of tall or closed forested communities, initiated by frequent fire, probably led to the extinction of this 'native bee'. Bee expert Charles Michener described and named the species in 1965 on the basis of this specimen, designating it as the ‘holotype’, and created the genus ''Hesperocolletes'' for H. douglasi alone. Unfortunately, no record of the circumstances of capture (e.g. flowers visited) is available.〔 To date, no other species of Hesperocolletes have been discovered and, despite searches made on Rottnest Island, Garden Island and coastal mainland areas north and south of Perth, ''H. douglasi'' has not been rediscovered. It is officially listed as ‘presumed extinct’ under the Western Australian Wildlife Conservation Act. Nevertheless, there is a possibility that the species might survive somewhere in Western Australia. Only the diagnostic features of the male can be given and the reader should be aware that, generally speaking, females differ from males in certain anatomical characters and sometimes the differences can be dramatic. ''Hesperocolletes douglasi'' is superficially like a number of other native bees and careful examination under a microscope would be required to distinguish a specimen. The bee is about the same size as a honeybee (body length approximately 12 mm), generally black and brown and moderately hairy.〔 The species belongs to the large family Colletidae and, in particular, the subfamily Paracolletinae. Colletids are characterized by having a short, broad, blunt tongue (or ‘glossa’) (a flexible, hairy appendage at the end of the proboscis; not always visible as it can be retracted). Paracolletines (at least in most species, including H. douglasi) have three submarginal cells in the fore wing and females usually have densely hairy hind legs (for carrying pollen). The diagnostic characters of ''Hesperocolletes'' can occur individually in various paracolletine bees and it is the combination of those features that one must look for: lower part of face yellow-brown; labrum (a hinged flap attached to the lower margin of the face) more than twice as wide as long and not strongly convex; a distinct carina (sharp edge) around and especially behind each compound eye; tarsal claws with inner prongs expanded and flattened.〔 == See also == * Australian native bee 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hesperocolletes douglasi」の詳細全文を読む スポンサード リンク
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