Alosa "oligorakered." The multirakered are primarily plankton feeders, the oligorakered have large rakers and are predators, and the medium-rakered generally consume a mixed diet. Most current species of the genus "Alosa" in North America can be found in Florida, whereas the distribution of most of them is broader. Morphology is notoriously liable to adapt to changing food availability in these fish. Several taxa seem to have evolved quite recently, making molecular analyses difficult. In addition, hybridization may be a factor in shad phylogeny. Nonetheless, some trends are emerging. The North American species except the American shad "A. sapidissima" can probably be
Cisco (fish) Cisco (fish) The ciscoes (or "ciscos") are salmonid fish of the genus "Coregonus" that differ from other members of the genus in having upper and lower jaws of approximately equal length and high gill raker counts. These species have been the focus of much study recently, as researchers have sought to determine the relationships among species that appear to have evolved very recently. The term "cisco" is also specifically used of the North American species "Coregonus artedi", also known as lake herring. In previous taxonomic classifications, the ciscoes have been identified as a subgenus "Leucichthys" of the genus "Coregonus". Based