On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg Author Martin, Peter text Zootaxa 2006 1138 1 44 journal article 10.5281/zenodo.172007 bd92c31d-534c-4bb2-a395-fb69e7ab01a9 1175­5326 172007 Sperchon denticulatus Koenike, 1895 Records ( Table 2 ): Benthos samples at two sites in Gutland, 16 individuals ( Gerecke et al. 2005 ). No larvae found in traps. Description of larvae: Walter (1922a) , as S. denticulatus (?) by Ullrich (1976) . Diagnostic characters of larvae: If the attribution of Ullrich's larvae to S. denticulatus is correct, they differ from the other Sperchon larvae presented here with regard to strikingly long setae on the dorsal idiosoma (up to 145µm). Remarks: The separation of adults of Sperchon denticulatus and S. hibernicus Halbert, 1944 , the two species of the S. denticulatus group, is only possible in males ( Viets & Viets 1959 ). As a result, all past reports on faunistics and larval morphology (e.g. Walter 1922a ) must be regarded with caution. The species is rhitrobiontic rather than crenobiontic and rare in Luxembourgian springs, obviously being present in anthropogenicically affected rheocrenes only ( Gerecke et al. 2005 ).