There may be!
Foongus
The Mushroom Pokémon
Type: Grass/Poison
Official Registration #: 590
Entry: A small, mushroom-like pokémon known for the fact that its cap strongly resembles a pokéball, especially when the rest of its body is concealed by tall grass. According to the official pokédex, the reason for this pattern is unknown. However, given that foongus are capable of learning Spore and Giga Drain, that their natural ability involves releasing toxic spores upon contact, and that their caps are the approximate size, shape, and coloring of an object human trainers would be most likely to pick up, this writer can say without a doubt that the reasoning behind this coloring is an absolute mystery that the scientific community may just never solve.
Amoonguss
The Mushroom Pokémon
Type: Grass/Poison
Official Registration #: 591
Entry: The evolved form of foongus, by battle experience. Upon evolution, amoonguss grow to be about two feet tall in height, and its cap expands proportionally. This makes its poké ball-like coloring less effective, even in the cover of tall grass, and as an added defiance of subtlety, it increases its own visibility by shaking its arms—both terminating in buds the size, shape, and color of its original head as a foongus—wildly in front of it. In theory, this is to attract attention to its arms and lure in prey with hypnotic motions. Also in theory, human beings have evolved a level of awareness and wisdom that would prevent such a tactic from working on us. In practice, however, this exact strategy is to blame for over 60% of all human hospitalizations in the vicinity of Unova’s Victory Road on an annual basis.
The Pokédex According to Bill 