Hydrachna williamsoni Soar, 1908,

Davids, Kees, Sabatino, Antonio Di, Gerecke, Reinhard, Gledhill, Terence & Smit, Harry, 2005, On the taxonomy of water mites (Acari: Hydrachnidia) described from the Palaearctic, part 1: Hydrachnidae, Limnocharidae and Eylaidae, Zootaxa 1061, pp. 36-64: 51

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http://doi.org/ 10.5281/zenodo.170186

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Hydrachna williamsoni Soar, 1908


Hydrachna williamsoni Soar, 1908 

Species incerta

Material examined: Female, NHML, C.F.G. "Dr. C. F. George coll. 1925 VI 24 144 ". "Lincolnshire Dr.C.F.George Coll. 1925 VI 24. 144. Balsam, 1904 ". Location of holotype unclear.

Discussion: The only specimen known in European collections is obviously a juvenile. From many points of view it is similar to H. processifera  (frontal area with poorly developed, roundish sclerite dots near postocularia, general shape of genital field, with L/ W 400 / 700, Cx­ 4 with a hook­like extension directed laterally). The transverse position of the gnathosoma and its appendages does not allow for measurements. As proposed by Gledhill & K.O. Viets (1976), this species should be considered a species incerta and not listed in faunistic inventories.


Natural History Museum, Tripoli