Found throughout the northern United States and is present in the FL-PRISM. Invasive Rank
Starry stonewort is a rooted macroalgae often found in lakes and rivers and can grow to two meters in length. This plant is green with star shaped rhizoids that form from late fall though winter.
Alewife is a species of ocean herring with a bluish-grey to olive back with silvery sides. The body is wide, narrows at the belly, and averages 6” in length. They have large eyes, a prominent black spot near the gill cover, and a forked fin.
The round goby is a small, soft-bodied fish with a distinctive black spot on the first dorsal fin. They have large, protruding eyes and range in length from 4″ to 10″. While juveniles are grey, adult round gobies have grey, black, brown, and olive green markings.
Yellow floating heart is an herbaceous perennial that has stout, branching stems. The heart-shaped, almost circular, leaves are usually oppositely arranged and frequently purplish underneath. Bright yellow flowers have five petals and distinctively fringed edges. It spreads both vegetatively and by seeds.
Variable-leaf watermilfoil is a submerged perennial that looks like many native plants, including native milfoil species. It has 4-6 feathery leaves whorled around the stem, but some leaves can be alternating. Leaves are divided into 7-14 pairs of leaflets. Dense leaf arrangement gives this plant a bottle brush appearance. Stems are thick and reddish-brown. In mid to late summer, blade-like, serrated leaves with small, reddish pink flowers form an erect spike that emerges from the water.
Quagga mussels are filter-feeding freshwater bivalve mollusks. The quagga mussel is pale toward the end of the hinge and about 3/4″ wide.
Asian clam is a freshwater bivalve mollusk. The outside shells are yellow-green to brown with elevated concentric rings. If the color chips away, white spots can be seen underneath. The inside of the shells may be light purple. Adults are small, usually less than 1 1/2″ in length.
Fishhook waterfleas are tiny crustaceans less than 1/2″ long with long, sharp, barbed tails. The fishhook waterflea has a slender spine and prominent S-shaped loop on the tail. Fishhook waterfleas collect in gelatinous globs on fishing equipment and lines.