Belongs within: Hydrachnidia.
Contains: Eylais.
The Protohydrachnidia are a clade of water mites in which the lateral eyes lack muscles, the last pair of idiosomal dorsoventral muscles are arranged in a median position, and the ejaculatory complex has the distal-sclerite arms and apical setae reduced. They include the Hydrovolzioidea which have small, inconspicuous genital acetabula positioned on the coxal plates IV (Walter et al. 2009).
<==Protohydrachnidia |--HydrovolzioideaTBG00 | |--Hydrovolziidae [Hydrovolziinae]WWO01 | | |--Stygovolzia Imamura 1957TBG00 | | | `--S. uenoi (Imamura 1957)TBG00 | | |--Hydrovolziella Viets 1935TBG00 | | | `--*H. lata (Walter 1935) [=Hydrovolzia lata]TBG00 | | `--Hydrovolzia Thor 1905TBG00 | | |--H. baderiG96 | | |--H. cancellata Walter 1906TBG00 | | |--H. gerhardiTBG00 | | |--H. japonica Imamura 1961TBG00 | | |--H. marshallaeWL09 | | |--H. persica Bader & Sepasgozarian 1980TBG00 | | `--H. placophora (Monti 1905)TBG00 | `--Acherontacaridae [Acherontacarinae]TBG00 | |--Bharatavolzia Cook 1967TBG00 | | |--B. (Bharatavolzia) muscicola Cook 1967S86a | | `--B. (Bharatavolziella Cook 1967)TBG00 | | |--B. (B.) cooki Schwoerbel & Sepasgozarian 1980S86a | | `--B. (B.) pallida Cook 1967S86a | `--Acherontacarus Viets 1932 (see below for synonymy)TBG00 | |--*A. halacaroides Viets 1932TBG00 | |--A. bicornis Cook 1974TBG00 | |--A. cedro Lundblad 1962TBG00 | |--A. cicolaniiGS96 | |--A. dividuusTBG00 | |--A. fonticolus Viets 1934TBG00 | |--A. rutilans Angelier 1951TBG00 | |--A. tuberculatusTBG00 | `--A. vietsi Angelier 1951TBG00 `--EylaoideaWL09 | i. s.: Apheviderulix [Apheviderulicidae]WL09 | |--A. santanaWL09 | `--A. welwitchioidesWL09 |--PiersigiidaeWWO01 | |--StygolimnocharinaeWL09 | | |--Parawandesia Angelier 1951WL09, S86b | | | `--P. chappuisi Angelier 1951S86b | | `--Stygolimnochares Cook 1967H98 | | |--S. australica Cook 1986H98 | | `--S. elongata Cook 1967S86b | `--PiersigiinaeWL09 | |--Austrapiersigia montanaWL09 | `--PiersigiaWL09 | |--P. crustaWL09 | |--P. intermediaWi91 | `--P. limnophilaWL09 `--+--EylaisWo91 `--LimnocharidaeWWO01 |--LimnocharinaeWL09 | |--Limnochares Latreille 1796H98 | | |--L. (Cyclothrix) americanaWP99 | | |--L. aquatica (Linnaeus 1758)Wo91 [=Acarus aquaticusL02] | | |--L. australica Lundblad 1941H98 | | |--L. crinitaWL09 | | `--L. holoserica [=Hydrachna holoserica]G20 | `--Neolimnochares Lundblad 1937WL09, RFF05 | |--N. breviscuta Lundblad 1941RFF05 | |--N. kakadu Harvey 1990H98 | |--N. petrophila Lundblad 1937RFF05 | |--N. placophora Lundblad 1937RFF05 | `--N. pugiunculata Viets 1954RFF05 `--RhyncholimnocharinaeWL09 |--Austrolimnochares womersleyiWL09 `--Rhyncholimnochares Lundblad 1936RFF05 | i. s.: R. kittitannianaWL09 | R. womersleyi (Lundblad 1952) [=Paralimnochares womersleyi]H98 |--R. (Rhyncholimnochares)RFF05 | |--R. (R.) andina Lundblad 1953RFF05 | |--R. (R.) expansiseta Cook 1980RFF05 | |--R. (R.) gracilirostris Lundblad 1953RFF05 | |--R. (R.) lamellipalpis Lundblad 1936RFF05 | |--R. (R.) longipalpis Lundblad 1953RFF05 | `--R. (R.) longiscuta Lundblad 1941RFF05 `--R. (Paralimnochares Lundblad 1937)RFF05 |--R. (P.) dipersiai (Rosso de Ferradás 1975)RFF05 `--R. (P.) sursumhians (Lundblad 1937)RFF05
Acherontacarus Viets 1932 [incl. Acherontacarellus Lundblad 1962, Acherontacaropsis Cook 1967, Neoacherontacarus Bader 1989]TBG00
*Type species of generic name indicated
References
[GS96] Gerecke, R., & A. Di Sabatino. 1996. Historical zoogeography and evolution of habitat preference in water mites (Hydracarina) of the central Mediterranean region. In: Mitchell, R., D. J. Horn, G. R. Needham & W. C. Welbourn (eds) Acarology IX vol. 1. Proceedings pp. 523–527. Ohio Biological Survey: Columbus (Ohio).
[G96] Gil, M. J. 1996. Water-mite (Hydracarina) larvae of some selected genera from Spain: a phylogenetic inference. In: Mitchell, R., D. J. Horn, G. R. Needham & W. C. Welbourn (eds) Acarology IX vol. 1. Proceedings pp. 543–546. Ohio Biological Survey: Columbus (Ohio).
[G20] Goldfuss, G. A. 1820. Handbuch der Naturgeschichte vol. 3. Handbuch der Zoologie pt 1. Johann Leonhard Schrag: Nürnberg.
[H98] Halliday, R. B. 1998. Mites of Australia: A checklist and bibliography. CSIRO Publishing: Collingwood.
[L02] Latreille, P. A. 1802. Histoire Naturelle, générale et particulière des crustacés et des insectes vol. 3. Familles naturelles des genres. F. Dufart: Paris.
[RFF05] Rosso de Ferradás, B., & H. R. Fernández. 2005. Elenco y biogeografía de los ácaros acuáticos (Acari, Parasitengona, Hydrachnidia) de Sudamérica. Graellsia 61 (2): 181–224.
[S86a] Schwoerbel, J. 1986a. Acari: Limnohalacaridae and Hydrovolziidae. In: Botosaneanu, L. (ed.) Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) pp. 643–647. E. J. Brill/Dr W. Backhuys: Leiden.
[S86b] Schwoerbel, J. 1986b. Acari: “Hydrachnellae”. In: Botosaneanu, L. (ed.) Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) pp. 652–696. E. J. Brill/Dr W. Backhuys: Leiden.
[TBG00] Tuzovskij, P., D. Benfatti & R. Gerecke. 2000. The water mite family Acherontacaridae Cook, 1967 nov. stat. and diagnosis of the superfamily Hydrovolzioidea Thor, 1905 (Acariformes, Hydrachnidia). Acarologia 41: 451–473.
[WL09] Walter, D. E., E. E. Lindquist, I. M. Smith, D. R. Cook & G. W. Krantz. 2009. Order Trombidiformes. In: Krantz, G. W., & D. E. Walter (eds) A Manual of Acarology 3rd ed. pp. 233–420. Texas Tech University Press.
[WP99] Walter, D. E., & H. C. Proctor. 1999. Mites: Ecology, Evolution and Behaviour. CABI Publishing: Wallingford (UK).
[Wi91] Witte, H. 1991. The phylogenetic relationships within the Parasitengonae. In: Dusbábek, F., & V. Bukva (eds) Modern Acarology: Proceedings of the VIII International Congress of Acarology, held in České Budĕjovice, Czechoslovakia, 6–11 August 1990 vol. 2 pp. 171–182. SPB Academic Publishing: The Hague.
[Wo91] Wohltmann, A. 1991. Nutrition and respiratory rate of water mites (Actinedida: Hydrachnidia) from a phylogenetic point of view. In: Dusbábek, F., & V. Bukva (eds) Modern Acarology: Proceedings of the VIII International Congress of Acarology, held in České Budĕjovice, Czechoslovakia, 6–11 August 1990 vol. 2 pp. 543–548. SPB Academic Publishing: The Hague.
[WWO01] Wohltmann, A., H. Witte & R. Olomski. 2001. Organismal patterns causing high potential for adaptive radiation in Parasitengonae (Acari: Prostigmata). In: Halliday, R. B., D. E. Walter, H. C. Proctor, R. A. Norton & M. J. Colloff (eds) Acarology: Proceedings of the 10th International Congress pp. 83–99. CSIRO Publishing: Melbourne.