Alosa vistonica well-developed teeth on the palatine and vomer, especially in juveniles. Alosa vistonica Alosa vistonica is a species of shad, a freshwater fish in the Clupeidae family. It is endemic to a single shallow lake, Lake Vistonida in Greece. It is classified as critically endangered (CR) and is threatened by sewage, industrial effluents, destruction of spawning sites by agricultural development and increased salinity following the opening of a canal into the sea. It has been suspected to be extinct already. "A. vistonica" reaches a maximum length of 17 cm (SL). It is distinguished from other members of its genus entering freshwater
Fish fossil fish but also living gars and bichirs), cycloid, and ctenoid (these last two are found on most bony fish). There are even fish that live mostly on land or lay their eggs on land near water. Mudskippers feed and interact with one another on mudflats and go underwater to hide in their burrows. A single, undescribed species of "Phreatobius", has been called a true "land fish" as this worm-like catfish strictly lives among waterlogged leaf litter. Many species live in underground lakes, underground rivers or aquifers and are popularly known as cavefish. Fish range in size from the huge