Monographs Details: Endospora rubra 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 - Colonies variable in size, more or less cuboidal, with rounded corners, containing 8-32 cells, rarely 64 cells; cells pale aeruginous, more or less obscured by the pinkish or coral-red cell walls, at maturity angular; resting spores 8.5-9.5 µ diam.

Distribution and Ecology - Growing on lava rock among other Myxophyceae at Coamo Springs, no. 1916 a, type, and nos. 1912 a and 1923 a; on rocks near Laguna Joyuda, Mayagiiez, no. 1209 b and 1301 a; on old wood by Hot Springs, Coamo Springs, no. 405; north of Mayagüez, no. 1000 e.