108 ALGAE IN PHYTOPLANKTON OF THE UNITED STATES 



Division Cryptophyta 

 Class Cryptophyceae 

 Order Cryptomonidales 

 Family Cryptomonodaceae 

 GENUS CRYPTOMONAS Ehrenberg, 1831 (fig. 48) 



MORPHOLOGY 



Solitary, free-swimming cells are compressed, somewhat elliptical, 

 and broadly rounded to truncate at the anterior end. Two unequal 

 flagella are inserted into an evident gullet, which may be lined with 

 granular trichoblasts. A contractile vacuole is next to the gullet. The 1 

 to 2 large chromatophores are yellow to olive green but are sometimes 

 red. 



REPRODUCTION 



A mucilage surrounds an immobile stage prior to longitudinal divi- 

 sion into 2 daughter cells. 



OCCURRENCE 



Cryptomonas is found in the euplankton and tychoplankton. 



ENVIRONMENTAL CONDITIONS 



Standard 

 Range Mean deviation 



Temperature degrees Celsius 0.0 - 34.0 



pH 4.1 - 9.7 



Dissolved oxygen milligrams per liter .2 - 22.0 



Specific conductance micromho 20 -41,000 



Total alkalinity milligrams per liter - 477 



Total hardness do 3 - 2,000 



Total nitrogen do .01- 19.0 



Total phosphorus do .0 - 3.9 



SPECIES INFORMATION 



Refer to Pascher (1913) and Prescott (1962). 



