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) Author Smith, Ian M. Author Cook, David R. Author Gerecke, Reinhard text Zootaxa 2015 3919 1 111 156 journal article 10.11646/zootaxa.3919.1.6 4c40552e-e778-4d8e-a6b7-9662436cadc2 1175-5326 244587 F711CA99-1B2C-4E18-9F4B-7521D38D2303 Family Aturidae Thor, 1900 Aturidae (in part): Cook, 1974a , pp. 289–305. Aturidae + Axonopsidae : Smith, 1976 , pp. 9–11. Aturidae : Smith, 1977, pp. 953, 962, 966. Aturidae : Smith, 1984, pp. 308–310, 323–328. Aturidae (in part): K.O. Viets, 1987 , p. 164. Aturidae (in part): Smith & Cook, 1991 , pp. 553, 577, 578, figs. 16.133, 16.136, 16.139–16.143, 16.148–16.151, 16.268–16.271. Aturidae (in part): Smith & Cook, 1999 , pp. 118–119. Aturidae : Smith et al ., 2001 , pp. 580, 581, 613, 614, figs. 150–170, 348–379. Aturidae : Walter et al. , 2009 , pp. 267–268, 284–285, 290, figs. 13.37J, 13.37K, 13.53H–13.53J, 13.54A–13.54G. Aturidae : Smith et al ., 2010 , pp. 523, 524, 554, 555, figs. 15.150–15.170, 15.349–15.380. Aturidae : Gerecke, 2014, pp. 1–46, figs. 1–27. Diagnosis. Larva (modified from Smith 1984): Character states of pioniform hygrobatoid mites sensu Smith (1976) . Idiosoma elongate oval to nearly round in shape, moderately flattened dorsoventrally, and bearing twenty pairs of setae. Dorsum nearly covered by entire dorsal plate bearing four pairs of setae, namely vi , ve , si , and se anteriorly, or five pairs of setae including vi , ve , si , se anteriorly and c1 laterally. Dorsal plate surrounded by soft integument bearing two pairs of eyes anterolaterally and eight pairs of setae laterally including c1 , c2 , c3 , d1 , d2 , e1 , e2 , and f1 , or seven pairs of setae laterally when c1 is located on dorsal plate. Venter nearly covered by three pairs of expanded coxal plates. On each side, first coxal plate separate from second coxal plate, or fused with second plate with suture line distinct laterally and obliterated medially; second and third coxal plates fused with one another with suture line distinct laterally and obliterated medially where it merges almost imperceptibly with lateral coxal apodeme that is nearly parallel to anterior edge of second coxal plate. First coxal plate bearing setae 1a posteriorly and 1b at anterolateral angle; second coxal plate bearing setae 2b at posterolateral angle; third coxal plate bearing setae 3a anteriorly and, in some cases, pa near posteromedial angle. Third coxal plate with medial coxal apodeme present or absent and with transverse muscle attachment scar present or absent. Posterior edge of third coxal plate convex or nearly straight, and lacking or bearing prominent projections that may be elaborate when present. Excretory pore plate little larger than excretory pore and roughly round or quadrangular in shape, or much larger than excretory pore and nearly circular, triangular, quadrangular, broadly obcordate or roughly elliptical in shape, bearing setae ps1 medially and ps2 laterally, and, in some cases, h2 posterolaterally with ps2 displaced anteriorly or medially; excretory pore sessile. Numbers of setae and solenidia on leg segments as follows: ITi 7 to 9 (+ ϕ1 and ϕ2); ITa 11 to 13 (+ ω); IITi 7 to 9 (+ ϕ1 and ϕ2); IITa 11 to 13 (+ ω); IIITr 1; IIITi 7 or 9 (+ ϕ); IIITa 10 or 11. Trochanter of first leg with seta ITr1 long and anteroventral in position. Adults (modified from Cook 1974a ): Character states of the superfamily Hygrobatoidea (see Smith 1976 ). Idiosoma flattened dorsoventrally, with extensive dorsal and ventral shields. Dorsal shield entire or composed of numerous closely fitting platelets. Ventral shield incorporating coxal plates. Gnathosomal base separated from first coxal plates. Fourth coxal plate bearing or lacking glandularia. Genital field bearing three to many acetabula on plates flanking gonopore; surrounded by soft integument or variously fused with ventral shield. Pedipalp tibia with or without thick seta borne on ventral projection, unmodified distally, and lacking a spine-like or peg-like seta distomedially. Legs of males with segments unmodified or with distal segments variously modified. Subfamilies included. Albiinae Viets, 1925, Aturinae Thor, 1900, Axonopsinae Viets, 1929, Notoaturinae Besch, 1964. Distribution. Worldwide. Discussion. Cook (1974a) considered the family Aturidae to consist of five subfamilies, namely Frontipodopsinae Viets, 1931 including the genera Frontipodopsis Walter, 1929 and Karlvietsia Viets, 1962 , Axonopsinae Viets, 1929 including four large apparently monophyletic groups of related genera and a few distinctive genera with uncertain relationships, Albiinae Viets, 1925 including only the large worldwide genus Albia Thon, 1899 and the highly unusual monobasic genus Parasitalbia Viets, 1935 , Aturinae, Thor, 1900 including a moderately large group of related genera primarily in the Northern Hemisphere, and Notoaturinae Besch, 1964 including a diverse group of related genera in the Southern Hemisphere. Subsequently Cook (1986) assigned the Australian genera Tasmanaxona Cook, 1986 and Wheenyella Cook, 1986 to the Frontipodopsinae and Harvey (1989) placed the Australian genus Wheenyoides Harvey, 1989 in the same subfamily. Cook (1974a) and Smith (1984) pointed out that Frontipodopsis was not closely related to other aturids, and Cook et al . (2000) subsequently removed Frontipodopsis from the Aturidae and placed it in the monobasic family Frontipodopsidae . At the same time they transferred Tasmanaxona , Wheenyella , and Wheenyoides from the Frontipodopsinae to the family Wettinidae , and Karlvietsia from the Frontipodopsinae to the family Hygrobatidae , as part of a phylogenetic reassessment of basal hygrobatoid lineages. These authors also proposed a number of changes to the subfamily Axonopsinae (discussed below), leaving the Aturidae with four remaining subfamilies. Smith et al . (2001 , 2010) followed this subfamily classification as do we in the following treatment of the Aturidae .