Popis: |
Oospore wall ornamentation patterns as revealed by scanning electron microscopy (SEM) provide important taxonomic characters in the Charales. The present study illustrates inter- and intra-specific variations in the oospore wall ornamentation of five species of Chara, including eight intra-specific taxa. The type variety and form of C. globularis shows pusticular elevations with pores at the base of the elevation. The variety and form aspera of C. globularis shows a porous oospore wall, and the oospore is provided with a ribbon which bears nearly granular ornamentation. The type form of C. setosa has a granular oospore wall. The three forms of C. braunii show a similar type of ornamentation and support their placement under a single species. Chara corallina has a roughened oospore wall. Oospore dimensions studied at the population level are another feature included in the present study. The oospore dimension data (length, width fossa-breadth, number of striae) at the population level were analyzed statistically, and the results show species-specificity of these parameters. The significance of oospore wall ornamentation and dimensions are discussed simultaneously with morphological features. |