Biology of Finfish and Shellfish (2+1)

4.6.2. Substratum Spawners

These lay their eggs on substratum. They do not build nests. These substratum spawners are divided into 4 categories depending on the substratum.

a) Lithophils (Rock spawners): These fishes spawn on flat rocks, males clean the substratum. Courtship and fertilization takes place on the clean substratum. e.g: Gobies and Puffer fish

b) Phytophils (Plant spawners): these fishes deposit their eggs on plants or release their eggs among the plants. Sometimes the eggs are sticky. e.g.: cat fishes.

c) Aerophils (Terrestrial spawners)

These fishes deposit their eggs on the underside of the overlying rock or plant (above the water level). They deposit their eggs by pressing their belly against the rock or plant. Eggs are protected from predators and eggs are ensured with plenty of oxygen. In tropical areas, oxygen depletion will always be there and dehydration is overcome by spraying or splashing the water by males over the eggs which always keep the eggs moist. e.g.: Characin spp.

d) Pelagophils

These eggs are released in open water and these eggs are sticky. These adhesive eggs are always found in clusters (in clumps on clusters) and they are belayed. These eggs are protected by the fishes and the parental care is exhibited by both male and female fish. e.g: climbing perch