Phreatobrachypoda Cook, 1963

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 : 134

Genus Phreatobrachypoda Cook, 1963

Phreatobrachypoda (in part): Cook, 1974a, pp. 365–366.

Japonaxonopsis Imamura, 1984 , pp. 55–57, fig. 1.

Phreatobrachypoda (Phreatobrachypoda) : Smith, 1991, pp. 466–478, figs. 1–18. Phreatobrachypoda (in part): Smith & Cook, 1991, p. 613, figs. 371–373. Phreatobrachypoda (in part): Smith et al., 2001, p. 577.

Phreatobrachypoda (in part): Smith et al., 2010, p. 554, figs. 15.372–15.374. Phreatobrachypoda (Phreatobrachypoda) : Smith & Cook, 2010, pp. 292–298, figs. 1–14.

Diagnosis. Larva: Unknown.

Adults (modified from Smith 1991): Idiosoma elongate elliptical or broadly elliptical in shape. Idiosomal sclerites with surfaces smooth or finely reticulate. Dorsal and ventral shields separate from one another. Dorsal shield bearing three pairs of glandularia and one pair of well-defined longitudinal ridges that may be reticulate, with posterior region of shield truncated and slightly to greatly indented in males, and slightly constricted, depressed and bearing excretory pore, one pair of setae and one pair of lyrifissures in females. Dorsal furrow bearing two pairs of glandularia, two pairs of setae and three pairs of lyrifissures arranged on four to eight pairs of platelets in males, and two pairs of glandularia, one pair of setae, and two pairs of lyrifissures arranged on two or three pairs of platelets in females. Fourth coxal plate bearing coxoglandularium II, and lacking projection associated with opening for insertion of fourth leg. Ventral shield bearing one pair of glandularia posteriorly. Genital field bearing ten to fifteen pairs of acetabula; genital field and excretory pore incorporated into posterodorsal urogenital plate that also bears a pair of setae, in males; excretory pore separated from genital field and located on dorsal shield in females; acetabular plates separate from ventral shield in females. Fourth leg of males strongly bowed, with segments stocky and with distal segments variously modified and bearing rows of thick setae. Pedipalp tibia with a prominent ventral projection bearing two slender setae, and bearing a short seta distomedially that may be peg-like or spine-like.

Type species. Phreatobrachypoda multipora Cook.

Species included. Phreatobrachypoda multipora Cook (western North America), P. appalachiana Smith & Cook (eastern North America), P. gledhilli Smith (western North America), P. nozakiensis (Imamura) ( Japan), P. oregonensis Smith (western North America), P. virginiensis Smith & Cook (eastern North America).

Distribution. Holarctic (North America, Japan).

Discussion. Cook (1974a) and Smith (1991) considered Phreatobrachypoda to be a distinct genus. Smith & Cook (1991) and Smith et al. (2001, 2010) followed that treatment, as we do here but with a more restricted concept that excludes members of Ameribrachypoda , now considered to be a distinct genus.