Sarcoptijorm es 357 



Ewingidae Pearse, 1929 



Figure 287 



Diagnosis: The body of the ewingids is 



egg-shaped and has a few setae. Vertical 



setae are present. On the rear of the pro- 



podosoma is a transverse row of two long 



setae. No suture separates the propodo- 



soma and the hysterosoma. There is one 



pair of long setae on the anterior portion 



of the hysterosoma; few other minute 



body setae are present. The two-segmented 



palpi appear to form a tube enclosing the 



deformed chelicerae, which are not chelate ^'g»""^ ^^^ Ewingia cenobitae 



i_ ^ 1 1 *u ui u 1 • Pearse. Venter of female. 



but have only the movable chela remam- ^^^^^^ Pearse 1929) 



ing. Tarsi i and ii have claws but lack 



caruncles; legs in and iv are enormously thickened and transformed 

 into clasping organs without tarsal claws but with tarsi adapted as 

 claws. The genital opening lies between coxae in and iv and has (?) 

 two pairs of genital suckers. 



Genus: 



Ewingia Pearse, 1929 



Type. Ewingia cenobitae Pearse, 1929 



Discussion: Ewingia cenobitae Pearse is to be found in the gills of 

 the land hermit crab, Cenobita diogenes (Latreille), at Loggerhead, 

 Dry Tortugas, Florida. The mites cling near the outside of the gills 

 by means of the clasping adaptations of legs in and iv and the body 

 lies between the gill lamellae. Eggs containing fully developed larvae 

 apparently ready to hatch have been seen within several of the females. 

 The larvae possess six legs and are similar to the adults. Pearse also 

 examined the ghost crab, Ocypoda albicans (Bosc), but found no 

 mites. This may be due to the fact that these crabs often visit the 

 ocean to bathe their gills, whereas the hosts of the mite visit the ocean 

 only once each year to hatch their young. 



Reference: 



Pearse, A. S. 1929. Two new mites from the gills of land crabs. Carnegie 

 Inst. Wash. Publ. 391:225-230. 



