Red plants

Raiz is the internal name for a species of plant on SR388. They appear as purple and dark pink flower-like plants and are commonly found in narrow tunnels. The plants give off a purple glow and are harmful to Samus when she comes in contact with them. These plants often block alternative passages and access to power-ups. No Suit Samus acquires can negate their damage; the only effective protection against them is the Lightning Armor Aeion ability, which gradually depletes her Aeion Gauge instead of her Energy Meter. The Raiz serve a similar role to the vegetation encountered in Metroid II: Return of Samus.

It should be noted that the word "raiz" is Spanish for "root".