Geotriidae

noun

Distribution: southern South America, Australia and New Zealand. Lampreys are eel-like in shape. The skeleton is entirely cartilaginous. Jaws, scales and lateral fins absent. The larval (ammocoetes) stage lives for several years in fresh water before undergoing a radical metamorphosis and then as a rule returns to the sea. Non-parasitic species breed immediately after metamorphosis. Adults have well developed eyes and corneous teeth on the circular oral disk and the tongue. The larval stage is filter feeding, whereas the adult uses the sucker shaped mouth to attach to other fishes and feeds off the wound. Land-locked, lake populations or species are common in the northern hemisphere petromyzids, which also commonly appear as species pairs, with one species parasitic, and the other non-parasitic. The South American species, Geotria australis and Mordacia lapicida, are both anadromous.

The family Geotriidae belongs to the Class Cephalaspidomorphi (lampreys) and the Order Petromyzontiformes. It contains 2 genera and 4 species. It may be found in Marine, Brackish, and Freshwater environments and is primarily Peripheral/diadromous. This family may be found from 32° n to 55° s and 78° w to 178° e. Etymology of this family name: Greek, gea = the earth, dealing with earth