Volcano Lotus would seem to be related to a similar underwater plant from Super Mario Bros. 3 called Lava Lotus. The Volcano Lotus went on to appear in Super Princess Peach for the DS.
Volcano Lotus is only usable with the plains sprite set. (GFX09) Its leaves are created from one 16x16 tile, which is mirrored and use palette D. Its stem has three frames, each made of two 8x8 tiles. They are laid atop the middle of the leaf body and use palette C.
Volcano Lotuses can use a lot of processing power, so slowdown can occur if they're used in crowded areas.
Related ROM Addresses
Volcano Lotus' Tilemap
0x16212 [CE] Volcano Lotus's Leaf Tile (16x16 tile that is mirrored horizontally)
0x16208 [8E 9E E2] Volcano Lotus' Stem Tiles (Value is left 8x8 tile. Right tile is the next one over)
0x1625A  Palette/GFX page of Frames 1 and 2 of Volcano Lotus's top
0x16256  Palette/GFX page of Frame 3 of Volcano Lotus's stem
Volcano Lotus' Fireball
0x16291 [0C] Extended Sprite used by Volcano Lotus
0x11D94 [A6] 1st tile of Volcano Lotus' fireball
0x11D98 [B6] 2nd tile of Volcano Lotus' fireball
0x11D85  Palette/GFX page of Volcano Lotus' fireball