Asian Green Mussel
The Asian green mussel (Perna veridis) is an invasive
species to Florida which first began to appear in 1999. This animal
can grow to 6" in length and is characterized by its striking green
shell. Capable of attaching to any hard substrate by a series of
wiry structures known as byssal threads, these animals maybe found
on items such as rocks, pilings, seawalls, or even boat
propellers.
Image Credit: FWC