262 



Acarology 



List of superfamilies and families: 



Hydrovolziae 



Hydrovolziidae Thor, 1905 



Hydrachnae 



Hydrachnidae Leach, 1815 



Limnocharae 



Limnocharidae Kramer, 1877 

 Eylaidae Leach, 1815 

 Protziidae Viets, 1926 



Hydryphantae 



Hydryphantidae Thor, 1900 

 Clathrosperchonidae Lundblad, 



1936 

 Ctenothyasidae Lundblad, 1936 

 Eupatrellidae Viets, 1935 

 Hydrodromidae Viets, 1936 

 Rhynchohydracaridae Lundblad, 



1931 

 Thermacaridae Sokolow, 1927 



Lebertiae 



Lebertiidae Thor, 1900 

 Anisitsiellidae Viets, 1929 

 Atractideidae Thor, 1 902 

 Mamersopsidae Lundblad, 1930 

 Pseudohydryphantidae Viets, 

 1926 



Rutripalpidae Sokolow, 1934 

 Sperchonidae Thor, 1900 

 Teutoniidae Lundblad, 1927 



Arrhenurae Oudemans, 1902 

 Arrenuridae Thor, 1900 



Mideopsae 



Mideopsidae Thor, 1928 

 Acalyptonotidae Thor, 1929 

 A-Thienemanniidae Lundblad, 



1930 

 Krendowskiidae Lundblad, 1930 

 Mideidae Viets, 1929 



Pionae Viets, 1930 

 Pionidae Thor, 1900 

 Astacocrotonidae Thor, 1927 

 Feltriidae Thor, 1929 

 Hygrobatidae Koch, 1 842 

 Limnesiidae Thor, 1900 

 Nautarachnidae Viets, 1935 

 Neotorrenticolidae Lundblad, 



1936 

 Pontarachnidae Thor, 1929 

 Unionicolidae Oudemans, 1909 



Axonopsae 



Axonopsidae Viets, 1929 



S 



2. 



Key to the Hydrachnellae i 



Body strongly armored with several plates; genital suckers not 

 present; anal opening lying in plate of intermediate or large size 2 



Body may or may not be strongly armored but not as above; with 

 genital suckers (exception: Pontarachnidae); anal opening almost 

 without exception not lying in large plate; legs (except in Oxinae) 

 more or less radial 3 



Body strongly armored with several plates; three pairs of genital 

 suckers present; genital and anal openings in same ventral plate; 

 legs I and ii point anteriorly; legs iii and iv point posteriorly; no 

 swimming hairs; found in ocean Halacaridae 



Legs III and iv attached laterally so that epimera project beyond 

 edge of body and can be seen from above; epimera separated by 

 From Viets 1936. 



