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
Atlantic herring not considered to be an Arctic species. The small-sized herring in the inner parts of the Baltic Sea, which is also less fatty than the true Atlantic herring, is considered a distinct subspecies ("Clupea harengus membras") ("Baltic herring"), despite the lack of a distinctive genome. The Baltic herring has a specific name in many local languages (Swedish "strömming", Finnish "silakka", Estonian "räim", "silk", Livonian "siļk", Russian "салака", Polish "śledź bałtycki, sałaka", Latvian "reņģes", Lithuanian "strimelė") and is popularly and in cuisine considered distinct from herring. For example, the Swedish dish surströmming is made from Baltic herring. Herrings reach sexual maturity