Two new species of green snow algae from Upstate New York, Chloromonas chenangoensis sp nov and Chloromonas tughillensis sp nov (Volvocales, Chlorophyceae) and the effects of light on their life cycle development

摘要

Two new species of Volvocalean green snow algae are described from Upstate New York, Chloromonas chenangoensis and Chloromonas tughillensis. According to rbcL sequence analysis, these species belong to a subclade of five snow species of Chloromonas that includes Cr. brevispina. Cr. nivalis and Cr. pichinchae. These species have zoosporangia/garnetangia (cell packs) that are propelled by flagella. The life cycles of Cr. chenangoensis and Cr. tughillensis include a change ill cell shape front oblong to spherical before the loss of the cell wall. Using 8-h laboratory experiments. a peak in the change of cell shape occurred at 4 h for Cr. chenangoensis and between 2 and 4 h for Cr. tughillensis after the onset of light, and this was followed by a decline in change of cell shape for both species. Spherical cells peaked between 6 and 8 h for Cr. chenangoensis and at 8 h for Cr. tughillensis. Maximum total matings occurred at 4 h for Cr. chenangoensis and 6 h for Cr. tughillensis. which was followed by a peak in quadriflagellate zygotes at 8 h for both species, Mature zygotes (zygospores) were observed only in Cr. tughillensis.