Trom b idiform es 159 



TARSONEMINI CANESTRINI AND FANZAGO, 



1877 



The females possess a tracheal system behind the pedipalps; the 

 males perhaps may have a rudimentary stigma. The females usually 

 have a pair of latero-ventral, keglike pseudostigmatic organs between 

 coxae I and ii. The mouth parts are reduced. The two sexes are usually 

 differentiated. 



Key to the Tarsonemini 



1. Both males and females with four pairs of legs 2 



Females with one to three pairs of legs; males with three, seldom 

 four, pairs of legs Podapolipodidae 



2. Anterior dorsal body plate not forming a broad, rooflike covering 

 over mite; leg iv not ending in many whiplike setae 3 



Anterior dorsal body plate forming broad rooflike covering over 

 mite; leg iv ending in many whiplike setae, one "seta" may bear 

 pair of claws, being merely extremely modified portion of tarsus 



Scutacaridae 



3. Leg IV of female with ambulacra (claws and cup) 



Pyemotidae {— Pediculoididae) 



Leg IV of female without ambulacra, ending in terminal and sub- 

 terminal whiplike setae Tarsonemidae 



Podapolipodidae Oudemans, 1931 



Figure 107 



Diagnosis: Parasites of insects. The females lack spherical pseudo- 

 stigmatic organs and are without the complete number or with de- 

 formed legs; the female may be legless in the adult stage. The che- 

 licerae are needle-like, the palpi are rudimentary, and the legs have 

 claws and caruncle. 



This family shows the greatest degeneration or specialization of all 

 the mites, remaining more or less in the larval stage. The first stage is 

 a sexually undifferentiated larva which has three pairs of legs, the 

 posterior pair separate from the other two and almost on the end of 

 the body; on the posterior of the body is a small tubercle bearing two 

 adhering, long, whiplike setae which are lost in the adults. 



