Spiny Bog-plankton are a species of bog swarm native to Mantras.
Spiny Bog-plankton are small and round, with long, urchin-like spines covering their shell. They have two compound eyes set above a serrated mouth. The plankton can vary in color from brown to extremely light green.
As with most bog swarms, Spiny Bog-plankton form large groups, and are rarely seen alone. These bog swarms are carnivorous, using their serrated mouths to tear apart prey. While a few "Spinyees" are not dangerous, large groups have been known to attack creatures as large as Muck Medusae. Most creatures with armored skin are safe from such attacks, as Bog-plankton can not get any purchase on hard surfaces.