Stability of antheridial morphology in freshwater North American Vaucheria compacta var. dulcis J. Simons (Tribophyceae, Chrysophyta) grown under different salinities

C.W. SCHNEIDER, M.K. RILEY and B.M. STOCKTON (1996)

Aquatic Botany 52: 301-311.

Abstract

Freshwater North American isolates of Vaucheria compacta (Collins) Collins ex W.R. Taylor are compared to a European freshwater variety, V. compacta var. dulcis J. Simons, which was shown to differ in antheridial characteristics including axis curvature, number of lateral pores and the occurrence of antheridial clustering. Multiple isolates from Connecticut and Delaware, U.S.A. produced antheridia during the course of the study that were morphologically similar to European representatives of V. compacta var. dulcis. The number of lateral pores, curved antheridial axes, and relative lack of sympodial clustering remain consistent with V. compacta var. dulcis characteristics when cultured in a range of salinity from 0.0-16.0 ppt. Based upon these findings, we conclude that our tidal freshwater isolates represent the first records of V. compacta var. dulcis from North America.

Key words: Connecticut, Vaucheria compacta var. dulcis, Vaucheriaceae, Tribophyceae