Monographs Details: Stigonema hormoides var. constrictum N.L.Gardner
Authority: Gardner, Nathaniel L. 1927. New Myxophyceae from Porto Rico. Mem. New York Bot. Gard. 7: 1-144. pl. 1-23.
Description:Species Description - Filaments short, crooked, slightly branched, 11-13 µ diam., constricted at the dissepiments; cells quadrate to one-half as long as the diameter, slightly constricted when young, becoming much more so with age, pale grayish green; hormogoniferous branches very short; sheath very thin, hyaline or slightly colored when old.

Distribution and Ecology - Growing on damp fern roots and on soil about twenty kilometers north of Ponce, no. 1810, type.

Discussion:This form of Stigonema may readily be distinguished from the other forms of S. hormoides by the thin wall, which is deeply constricted at the dissepiments of the trichome.