Protzia distincta Walter, 1922

Sabatino, Antonio Di, Gerecke, Reinhard, Gledhill, Terence & Smit, Harry, 2009, On the taxonomy of water mites (Acari: Hydrachnidia) described from the Palaearctic, part 2: Hydryphantoidea and Lebertioidea, Zootaxa 2266, pp. 1-34 : 15

Protzia distincta Walter, 1922

Protzia macrognatha Walter, 1944 , nov. syn.

Material examined: Austria, National Park Gesäuse (locality abbreviations from the NP database): ETZ, Etzbachquelle (Kölbl Johnsbachquelle), 266.341 N 546.205 E; 861 m, 21.07.2007, main spring (8/13/1), riffles (3/8/0), pools (0/1/0), lateral spring with high conductivity (360 µS/cm) (33/40/4); SCHAF, Schröckengrabenquelle 1, 266.601 N 549.656 E; 1217 m, 17.07.2007 (0/3/3); SHRÖK E, large springs upstr. Ebneralm-Furt, 266.626 N 549.240 E; 1102 m, 19.07.2007 (5/5/2); SHRÖK H, spring line left affluent Klammbach 1, 266.689 N 549.285 E; 1115 m, 19.07.2007 (3/3/2); URO, captured spring West Unteres Rohr, 274.053 N 547.837 E; 698 m, 20.07.2007 (11/26/0).

Discussion: Only one of the two female type specimens collected in an affluent of the Austrian River Ybbs, from which Protzia macrognatha was described, is left at NHMB. Gerecke (1996) observed that from populations of other species in the P. eximia group, the lectotype of this species differs only in its rather large dimensions and ranked both P. d i s t i n c t a and P. macrognatha as subspecies of P. e x i m i a. After further variability studies on Alpine populations ( Gerecke 1999), P. d i s t i n c t a was characterized as a separate species, but the state of P. macrognatha remained questionable. The rich material now available from investigations on the spring fauna in the Gesäuse National Park allows an analysis of the considerable size variability within populations of P. d i s t i n c t a: Several exceptionally large specimens were found having anterior coxal plates exceeding 200 µm in L and a total chelicera L distinctly> 300 µm. Obviously, intraspecific size variability is high and not suitable for species discrimination in the P. eximia species group. Protzia macrognatha is consequently considered a synonym of P. d i s t i n c t a.