A NEW GENUS AND NEW RECORDS OF ALGAE IN THE CHLOROCOCCALES

Abstract

IN PLANKTON SAMPLES, taken during 1948-1950 from both temporary and permanent waters in Kansas, three genera of algae have been found that are new records for the United States, and one genus that is new to science. SIDEROCELIS.-This genus was first introduced by Naumann (1921) as a name for a section in the genus Chlorella. It was raised to generic rank by Fott (1935) and placed in the family Oocystaceae. The genus is similar to Oocystis but differs in that the wall is verrucate and does not expand during reproduction but ruptures immediately to release the autospores. S. ornatus (Fott) Fott (1935) ( Oocystis ornatus Fott, 1933) was first collected by the writer in Sept. 1948, from a moat around a monkey island in the city park of Chanute, Kansas. This species (fig. 1, 2) has ellipsoidal cells whose walls are embellished with small hemispherical verrucae. The cells measure 7-13,U long and 4-8.5u wide. Each cell contains 1-4 parietal chloroplasts without pyrenoids. The usual number of autospores is four, though in the Kansas specimens some were observed to have produced two, and others eight autospores. The Kansas specimens varied from 8-124u long and 5-11.6kU wide. The verrucae were arranged in spiral rows from pole to pole. S. ornatus was also collected from a roadside pond near Welda, Kansas in Oct. 1948 and May 1949; and from Hayden'.s pond, Lawrence, Kansas in May 1950. SIDEROCELIS hexacosta sp. nov. (fig. 3-5). Cellulae ellipticae, 7-13,u longae et 6-9k latae sunt. Verruculae apicium parvae et hemisphaericae sunt. Verruculae mediae longulae et prominentes sunt. Progeneratio 4-8 autosporibus. Cells elliposoidal, 7-13k long and 6-9k wide. Apical verrucae are small and hemispherical. The equatorial verrucae are elongate and prominent. Reproduction is by 4-8 autospores. The median elongate verrucae distinguish this species from all other described forms. Collected Sept. 1949 near Chanute, Kansas. Type material, No. 49101, preserved in formalin. DICHOTOMOCoccus.-The genus Dichotomococcus was erected by Korschikov (1928) on the single species D. capitatus. Fott (1948) described two new species D. lunatus Fott and D. elongatus Fott. The last named species (fig. 6) was fairly abundant in the plankton of a small, shallow pond near Chanute, Kansas. Dichotomococcus is a colonial alga, characterized