Monographs Details: Placoma willei 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 75-100 µ (up to 350 µ) diam., spherical, subspherical or irregular in outline, tough and cartilaginous, more or less gelatinous on the surface; cells spherical, 2-2.4 µ diam., usually appearing in groups of 2 or 4 on the surface of the colony; colonial tegument more or less hyaline; individual cells and groups of 2-4 enclosed in special teguments more or less deeply colored violet or purplish.

Distribution and Ecology - Growing at "Campo" north of Maricao, no. 1290 c, type collected by Dr. N. L. Britton; on bark, Utuado, no. 1506 c; on rocks, near Laguna Joyuda, Mayagiiez, no. 1209.