Monographs Details: Microcoleus amplus N.L.Gardner
Authority: Gardner, Nathaniel L. 1927. New Myxophyceae from Porto Rico. Mem. New York Bot. Gard. 7: 1-144. pl. 1-23.
Family:Phormidiaceae
Description:Species Description - Filaments tortuous, mostly open at the apices with extruding trichomes, smaller, younger ones closed; 30-60 trichomes densely entwined in the center of the filaments, 4.6-5 µ diam., very bright blue-green in color, 2-3 cells attenuated at the apices, not constricted at the dissepiments; cells quadrate to twice as long as broad, densely congested with fine irregular granules; crosswalls very distinct; apical cell conical; sheath white, smooth, homogeneous, ample, 9-12 µ thick.

Distribution and Ecology - Growing on mud by a stream near Rio Piedras, no. 72, type; n earth at the Experiment Station, Rio Piedras, no. 179; on arth, Utuado, nos. 1505 and 1573.

Discussion:

PLATE 11, FIGURE 3

Microcoleus amplus has close affinities with M. vaginatus Gomont, M. paludosus Gomont, and M. lacustris Farlow. From the first it differs in not having capitate trichomes and in having longer cells; from the second in having smaller trichomes and shorter cells; and from the last in not having constricted or dolioform cells, and in having more acute apices. It differs from all three in having a more ample sheath.