Arrenurus female – Specie incerta

Fig 10 - Arrenurus female - dorsal

Water mite caught the 1st of May 2012 in a natural pond in Cerfontaine (Belgium). Length 1280 µm and width : 1050 µm.

Log of my attempt to identify this water mite.

Arrenurus female are much harder to identify than their male counterpart. In Viets (1936) I found a lot of plates to help to identify this one.

Here are some possibilities provided by Viets with the size given by Viets and some observations about the drawing given.

Arrenurus radiatus 1400:1100 P459. Acetabular plates too large.
Arrenurus curvisetus 1200:930 P461. Genital plate too narrow ?
Arrenurus membranator 900 P465. Drawing not very precise.
Arrenurus mülleri 960-1000:750 P466. Anchoral process of first pair of coxa.
Arrenurus nobilis 1600:1230 P466. Genital plates with and angle, first pair of coxae more narrow.
Arrenurus buccinator 1300 P467. Anchoral process of first pair of coxa. (to double check ?)
Arrenurus papillator 1900:1600 P467. Angle in genital plate, posterior of first coxa.
Arrenurus pugionifer 1000:800 P468. Third pair of coxa too narrow.
Arrenurus bifidicolus 1000 P469. First pair of coxa.
Arrenurus fasciolatus 1060:945 P469. Almost a perfect match (except tht mine is much larger). The genital plates are maybe a little bit too large ?

Note : I give up for the identification of this Arrenurus.

Fig 20 - Arrenurus femalee - Ventral view