56 ALGAE IN PHYTOPLANKTON OF THE UNITED STATES 



Division Euglenophyta 

 Class Euglenophyceae 

 Order Euglenales 

 Family Euglenaceae 

 GENUS TRACHELOMONAS Ehrenberg, 1833 (fig. 22) 



MORPHOLOGY 



Cell is solitary and uniflagellate and loosely encased in a globose or 

 ellipsoidal lorica. The surface of the lorica may be smooth, punctate, 

 spiny, reticulate, or striate. There are 2 to 15 parietal, discoid 

 chromatophores. 



REPRODUCTION 



Prior to division into 2 daughter cells, the parent cell becomes im- 

 mobile. One daughter cell is released to form a new lorica. The remain- 

 ing daughter cell retains the parent-cell lorica. 



OCCURRENCE 



The genus is very indicative of warm waters having a high content of 

 organic matter. It can occur in such abundance as to color the water 

 brown. It is found primarily in the tychoplankton. 



ENVIRONMENTAL CONDITIONS 



Standard 

 Range Mean deviation 



Temperature degrees Celsius 0.0 ■ 



pH 4.0 - 



Dissolved oxygen milligrams per liter .2 - 



Specific conductance micromho 10 



Total alkalinity milligrams per liter 



Total hardness do 3 



Total nitrogen do .02- 



Total phosphorus do .0 - 



SPECIES INFORMATION 



Refer to Deflandre (1926), Skvortzow (1925), and Prescott (1962). 



