Sea horse . Seahorses or hippocampi (genus Hippocampus) constitute a group of marine fish belonging to the Syngnathidae family, which also includes pipe fish. Its name is due to the peculiar similarity that its head presents with that of horses. In fact, the characteristic of having the head at a right angle to the rest of the body does not occur in any other genus of fish.
Summary
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- 1 Features
- 2 species
- 3 Habitat
- 4 Food
- 5 Reproduction
- 6 Sources
characteristics
The body of the seahorse is covered by an armor of plates or rings of bone constitution. Their way of swimming is very different from that of other fish. They adopt an upright position, pushing with its dorsal fin. They have no anal fin. Instead they have a prehensile tail that spirals and allows them to cling to underwater stems and plants. In this animal species it is the male who is responsible for the development of the eggs. The female uses her ovipositor to insert the mature eggs into the male’s incubator bag, where they are fertilized
Species
There are currently approximately 50 known species of seahorses. The size of the adults varies according to the species, from the smallest Hippocampus minotaur that was discovered in Australia and is 15 mm long, to Hippocampus ingens that exceeds 9 cm in length
Habitat
They are distributed globally in the strip located between both tropics and live in temperate waters, being in the Atlantic areas where they are most abundant and their biodiversity is greatest. They live among algae, mangroves and corals. At least two species can be found on the coasts of Spain: Hippocampus hippocampus and also Hippocampus ramulosus.
Feeding
Seahorses are predators of small invertebrates. They have a visual system with eyes that are independently mobile, help them recognize their prey, small crustaceans that are part of the zooplankton. When the prey comes within reach it is sucked through its bony snout by a quick movement of its head. They swallow their prey whole without teeth, and are forced to consume large amounts of food.
Reproduction
The female uses her ovipositor to insert the mature eggs into the male’s incubator bag. The fertilization of the eggs takes place inside the bag. However, a recent study has shown that sperm are actually released outdoors and that fertilization occurs at the same time that the eggs enter the male’s sac. Both the entry of the eggs in the bag and their incubation occur in an extremely fast process (just 6 seconds). This strategy is one more way to ensure that the eggs come exclusively from a single female, thereby ensuring genetic monogamy for that batch of eggs. Oxygen diffuses through the capillaries of the tissue that lines the eggs. Hormones help create a placental fluid that bathes a small part of the egg that protrudes from the tissues of the bag.
The medium created by the fluid in the pouch is altered during the procreation process, going from being similar to body fluids to resembling the surrounding sea water, presumably to reduce the stress of the offspring at the time of birth. The gestation period lasts between 10 days and 6 weeks, depending on the species and the temperature of the sea water. After this period, the male lets the young come out of the interior of his bag for several hours, contracting his body to apply pressure and release them. The young are miniature replicas of their parents, about seven to eleven millimeters long. They are completely independent and do not return to the bag after birth. Females appear to mature at the same time as males, their ovipositor being visible when transferring the ovules to the male. It can be influenced by the light, temperature and turbulence of the sea water in the area.
