How do agnathans reproduce

Lampreys reproduce in freshwater riverbeds, working in pairs to build a nest and burying their eggs about an inch beneath the sediment. The resulting hatchlings go through four years of larval development before becoming adults.

How do Agnatha reproduce sexually or asexually? They reproduce asexually and sexually. After the female releases her eggs the male lets out a sperm which fertilizes the eggs. Class Agnatha consists of an ancient group of animals similar to fish but with some very noticeable differences. The agnathans lack jaws and paired fins. Instead of jaws, they have a cyclostomic circular toothed mouth with which they bore into the side of a fish and suck the blood of their victim.

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The hagfish is almost completely blind, but it has a good sense of touch and smell. It has a ring of tentacles around its mouth that it uses to feel for food. It has a tongue-like projection that comes out of its jawless mouth. At the end of the projection are tooth-like rasps that close when the "tongue" is pulled back into the hagfish's mouth.

The hagfish eats marine worms and other invertebrates. It has a very low metabolism and can go for as long as seven months without eating. Newly hatched hagfish are miniature copies of the adult hagfish.

The hagfish is found in cold ocean waters in the Northern and Southern Hemispheres. It is found on muddy sea floors and may live in very large groups of up to 15, individuals. There are about 60 species of hagfish. Agnatha Photo Gallery.

Brook Lamprey - Lampetra planeri The brook lamprey is found in small brooks, streams, lakes, and rivers across Europe. Northern Brook Lamprey - Ichthyomyzon fossor Northern brook lamprey are found in many areas of the midwestern and northeastern United States.

Pacific Hagfish - Eptatretus stoutii The Pacific hagfish is also known as the slime eel. Pacific Hagfish - Eptatretus stoutii The hagfish can tie itself into a knot. Pacific Hagfish - Eptatretus stoutii Hagfish eat worms and invertebrates, but they also enter both dying and dead fish and eat them from the inside out.