COUCH: DISEASES AND PARASITES OF PENAEID SHRIMPS 



Figure 21.— Telotroch stage (arrow) 

 of Zoothamnium produced from divi- 

 sion of trophont (phase contrast); this 

 is the dispersal stage for the species; 

 the telotroch is motile and possesses a 

 ventral girdle of cilia. Note the 

 trophont at upper right with extended 

 adoral ciliature (arrow). x500. 



by Lightner (1975) in Texas. From a photomicro- 

 graph Icindly loaned to me by Johnson, I have 

 tentatively identified this loricate peritrich as 

 Lagenophrys lunatus. This species is commonly 

 found on the cuticle of paleomonid shrimps along 

 the east coast and gulf coast of the United States, 

 but Johnson's report, if accurate, is the first for a 

 penaeid. It is possible that the species of shrimp 

 examined by Johnson was a grass shrimp, 

 Paleomonetes sp. Species of Lagenophrys are usu- 

 ally host specific, and though I have examined 

 many penaeid shrimps, I have not observed 

 Lagenophrys sp. on any. Couch (1971) gave a de- 

 tailed discussion of the possible effects of 

 Lagenophrys spp. on the cuticles and gills of de- 

 capod Crustacea with particular reference to L. 

 callinectes on the gills of the blue crab, Callinectes 

 sapidus. Erosion of cuticle surface and interfer- 

 ence with gas exchange at the gill surface in heavy 

 infestations are possible effects of Lagenophrys. 



Order Apostomatida Chatton and Lwoff 1928 

 Family Foettingeriidae Chatton 1911 

 Genus Uncertain 



The encysted form (phoront) of an undescribed 

 apostome ciliate has been observed on the gills of 

 Penaeus duorarum (Figures 22, 23) in northwest 

 Florida. The cysts are decumbent, ellipsoidal 

 bodies that are 41 jxra wide by 60 /u,m long (range: 

 20.7-41.4 /Ltm by 27.6-60.0 /xm). The cyst wall is 

 from 1 to 3 /xm thick and is semitransparent. 



Heavy infestations of this ciliate occur on gills of 

 pink shrimp during periods of warm to moderately 

 cool weather when shrimp are held under crowded 

 conditions (Figure 22). The cysts are most often 

 attached to the gills at the point of branching of 

 the distal processes variously termed lamellae, 

 filaments, or tertiary structures (Figure 22). The 

 lifecycle of this ciliate has not been elucidated, and 

 it cannot be assigned to a genus until silver- 



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