From the Super Mario Wiki
Floro Sapiens are a race of plant-like creatures that appear in Super Paper Mario. Their name is a pun on the scientific name for humans, Homo sapiens (Latin for "wise man"), replacing the genus name for Flora, meaning "plant life" (making their full name "wise plant" in Latin). They loosely resemble Crazee Dayzees, except with stem-like bodies. Their leader is King Croacus IV, who goes crazy after the Cragnon race inadvertently pollutes the Floro Sapiens' water with their wastes. The pollution sickens other Floro sapiens as well, and in retaliation, they begin to kidnap Cragnons, brainwashing them with Floro Sprouts and having them help mine the Floro Caverns for jewels for King Croacus' palace.
Floro Sapiens' petals come in three colors: yellow, orange, and purple. Statistic-wise, all Floro Sapiens are the same, however. They attack by throwing their heads, and even if the head is destroyed, the bodies can continue functioning.
Throughout Chapters 5-1 and 5-2, Mario, Princess Peach, Bowser, and Tippi find themselves chasing down a band of Floro Sapiens carrying Cragnon prisoners. The Floro Sapiens will attack the player unless they are wearing a dead Floro Sprout on their head, fooling the flowers into thinking they're brainwashed and harmless. Eventually, the party discovers the secret entrance to the Floro Caverns and eventually defeat King Croacus, uncovering the truth about the pollution. The entire story is recorded by the Cragnon documentarian Flint Cragley, who vows to show the footage to his people and put a stop to the pollution, thus ending the feud between the two races.
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