MALLOMONAS-CONNENSIS SP-NOV, A NEW SPECIES OF SYNUROPHYCEAE FROM A SMALL NEW-ENGLAND LAKE, USA

A new species of Mallomonas, M. connensis sp. nov., is described from a eutrophic locality in Connecticut, U.S.A. with a relatively high pH and specific conductance. Cells are covered with bristles and have scales that are orientated with their longitudinal axes perpendicular to the longitudinal axis of the cell. Each scale of the apical ring is highly asymmetrical with a forward projecting triangular shaped extension; collectively the extensions form an opening through which the flagellum emerges. Body scales possess a prominent Ushaped ridge that transverses the scale near the center and extends forward. A series of more or less concentric ribs cover the U-shaped ridge and dome, and circumscribe a more light and electron transparent region. The combination of characters of the bristles is unique among taxa of Mallomonas.