Ninespine stickleback stickleback species, such as the Brook Stickleback. Ninespine stickleback The ninespine stickleback ("Pungitius pungitius"), also called the ten-spined stickleback, is a freshwater species of fish in the family Gasterosteidae that inhabits temperate waters. It is widely but locally distributed throughout Eurasia and North America. Despite its name, the number of spines can vary from 8 to 12. The body of the ninespine stickleback tapers to a very narrow caudal peduncle and the caudal fin is fan-shaped. The body is less deep and more elongated than that of the three-spined stickleback with a thinner and longer caudal peduncle, but the best
Avicularium shape as the autozooids. Interzooidal avicularia are wedged between autozooids but do not replace an autozooid. Adventitious avicularia are placed somewhere on the external (frontal) wall of an autozooid and are usually much smaller. The 'birds-head' avicularium (e.g. "Bugula") is elevated above the colony by a stalk (peduncle). A zooid where the operculum is modified into a very long, hair-like structure is called a vibraculum. The cylcostome family Eleidae, which convergently evolved an opercular structure during the Early Cretaceous to Paleocene, also possess avicularia-like zooids. Avicularium The avicularium (pl. avicularia) in cheilostome bryozoans is a modified, non-feeding zooid. The operculum,