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.


  • Viets, K. (1936). VII : Wassermilben oder Hydracarina. Tierwelt Deutschlands.


More pictures.

Fig 20 - Arrenurus femalee - Ventral view

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