Pionides Thor, 1901

Smith, Ian M., Cook, David R. & Gerecke, Reinhard, 2015, Revision of the status of some genus-level water mite taxa in the families Pionidae Thor, 1900, Aturidae Thor, 1900, and Nudomideopsidae Smith, 1990 (Acari: Hydrachnidiae), Zootaxa 3919 (1), pp. 111-156 : 126

Genus Pionides Thor, 1901

Tiphys (Pionides) : Cook, 1974a, p. 282, fig. 1199. Pionides: Smith, 1976 , pp. 46, 90, 92.

Tiphys (Pionides) : Wainstein, 1980, pp. 196, 198, figs. 668–675.

Diagnosis. Larva: (modified from Wainstein 1980). Character states of the subfamily Tiphyinae. Third coxal plate with transverse muscle attachment scar present. Excretory pore plate nearly circular with setae ps1 well anterior to setae ps2; excretory pore sessile.

Adults (modified from Smith 1976): Character states of subfamily Tiphyinae. Fourth coxal plates with large, anteriorly concave projections covering insertions of fourth legs. Pedipalp with segments relatively long and slender and with tibia bearing a long, blade-like seta distomedially on a moderately prominent projection. Genital field bearing three pairs of acetabula. Males with genital acetabula relatively close together and borne on triangular acetabular plates that are fused posterior to gonopore but separate anterior to gonopore, and do not extend laterally beyond posteromedial angles of fourth coxal plates; second leg with tibia lacking two spatulate setae distoventrally and fourth leg with genu bearing a long, curved, blade-like seta distodorsally but with other segments not expanded and with setae not highly modified. Females with genital acetabula relatively widely separated from one another and borne on triangular acetabular plates and with second and third acetabula on each side not forming a row near posterior edge of plate that is nearly at right angles to long axis of idiosoma.

Type species. Piona ensifer Koenike.

Species included. Pionides ensifer (Koenike) (Europe) (monobasic).

Distribution: Europe.

Discussion. Cook (1974a) treated Pionides as a subgenus of Tiphys . Smith (1976) elevated Pionides to full generic rank and we follow that treatment here.