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

R.W. Hoham, J.D. Berman, H.S. Rogers, J.H. Felio, J.B. Ryba andP.R. Miller. 2006. Two new species of green snow algae from Upstate New York, Chloromonas chenangoensissp. nov. and Chloromonas tughillensissp. nov. (Volvocales, Chlorophyceae) and the effects of light on their life cycle development. Phycologia45: 319–330. DOI: 10.2216/04-103.1Two new species of Volvocalean green snow algae are described from Upstate New York, Chloromonas chenangoensisand Chloromonas tughillensis. According to rbcL sequence analysis, these species belong to a subclade of five snow species of Chloromonasthat includes Cr. brevispina, Cr. nivalisand Cr. pichinchae. These species have zoosporangia/gametangia (cell packs) that are propelled by flagella. The life cycles of Cr. chenangoensisand Cr. tughillensisinclude a change in cell shape from 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. chenangoensisand between 2 and 4 h for Cr. tughillensisafter 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. chenangoensisand at 8 h for Cr. tughillensis. Maximum total matings occurred at 4 h for Cr. chenangoensisand 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.