Asian Green Mussel Perna veridis
The Asian green mussel 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