Janszoonia, Smit, 2007

Smit, Harry, 2007, New Records of Hyporheic Water Mites from Australia, with a Description of Two New Genera and Ten New Species (Acari: Hydrachnidia), Records of the Australian Museum 59 (2), pp. 97-116 : 112

Janszoonia n.gen.

Diagnosis. Characters of the family Athienemanniidae and the subfamily Notomundamellinae . Dorsal and ventral shields present, dorsal furrow complete. Dorsal shield large, with three pairs of glandularia and a pair of postocularia. Dorsal shield without apophyses. Eyes absent. Eight pairs of acetabula on small platelets within the gonopore, four pairs on the posterior platelets, one pair on the middle platelets and three pairs on the anterior platelets. Laterally of gonopore, four small acetabula irregularly placed on a ridge-like structure. Palp rotated.

Type species: Janszoonia difficilis n.sp.

Etymology. Named after the Dutch sailor Willem Janszoon, possibly the first European to reach Australia in 1606. The gender is feminine.

Remarks. From Australia three genera are known: Notomundamella Cook , Mellamunda Harvey and Davecookia Harvey , all belonging to the endemic subfamily Notomundamellinae . The latter genus is described from the same locality as the new genus described here. None of the known members of the Notomundamellinae has a similar configuration of the acetabula. Notomundamella has a dorsal shield with apophyses (absent in the new genus), while the gonopore has three lobes with numerous acetabula. Mellamunda has eight acetabula within the gonopore, but not on platelets, and 5–7 pairs in the ventral shield. Davecookia has five pairs of acetabula within the gonopore (three large pairs and two small ones), no acetabula in the ventral shield and the female has a very broad gonopore. The new genus is most closely related to Mellamunda , as both females have acetabula within the gonopore and acetabula incorporated into the ventral shield. However, the genital field of Mellamunda differ completely from those of the new genus. The acetabula of Mellamunda are partly covered by the idiosoma and not on platelets. The acetabula of the new genus within the integument are lying on platelets, while those outside the integument are located on a ridge-like structure. These differences warrant a separate status of the new genus.