390 Acarology 



4. Hysterosoma cylindrical; genital opening small, far to rear and in 

 front of anal opening Eulohmanniidae 



Hysterosoma pouchlike or baglike; genital opening far to front; 

 space between anal and genital openings equal to length of anal 

 opening Nanhermanniidae 



Genital and anal openings each lying in separate ventral plate 



Epilohmanniidae 



5. Genital and anal opening large, touching each other and covering 

 entire length of opisthosoma 6 



Genital and anal opening moderately small, more or less trapezoid 

 shape or oval, separated from each other by distinct section of 

 ventral plate 13 



6. Genital and anal opening in common, narrow frame 7 



Genital and anal opening not in narrow frame, but in broad, com- 

 mon, ventral plate that reaches to lateral margins of hysterosoma 10 



7. Hysterosoma with flat venter and dorsum either flat or weakly 

 arched 8 



Hysterosoma cylindrical Lohmanniidae 



8. Dorsum of hysterosoma lightly arched 9 



Dorsum of hysterosoma flat, usually with raised margin or sunken 

 dorsal surface Camisiidae 



9. With pseudostigmata and pseudostigmatic organs; with or without 

 transverse sutures on hysterosoma Hypochthoniidae 



Without pseudostigmata or pseudostigmatic organs and in their 

 place only simple setae; no transverse sutures Malaconothridae 



10. Adults bearing cast skins of immature stages on dorsum 11 



Adults not bearing cast skins on dorsum of hysterosoma which is 

 strongly arched Hermanniidae 



11. Without tubelike or other projections on lateral margins of 

 hysterosoma 12 



With tubelike or other projections on lateral margin of hystero- 

 soma Hermanniellidae 



12. Dorsum of hysterosoma flat or weakly arched; genital plates 

 divided by transverse suture Neoliodidae 



Dorsum of hysterosoma flat; body and legs covered by thick layer 

 of secretion; genital plates not divided by transverse suture 



Plateremaeidae 



