Habitat: Often attached to rock or dead coral in a variety of habitats, or growing on mangrove prop roots. Distribution: Florida, Bahamas, Greater Antilles, Lesser Antilles, Southern Caribbean, Western Caribbean, Gulf of Mexico Characteristics: Spiny thallus varying in color from light yellow to red black. Axes are polysiphonous and fully corticated (Image 2). Branches are cylindrical and smooth while short abundant branchlets have multiple spines. Hair-like filaments (trichoblast) usually present at branch apices.