Hippocampus erectus

 Lined Seahorse

Hippocampus erectus Perry, 1810 or Lined seahorse (EN), Cavalo-marinho-raiado (PT), Caballito estriado (SP), Hippocampe Rayéltalian (FR) or Amerikansk Jättesjöhäst (SE) can be found in a diversity of colours such as ash grey, orange, yellow, brown, and dark red. Its body is adorned with elaborated skin fronds, its head and trunk with white contours and its tail with tiny white dots. 

The Lined seahorse is distributed along the western Atlantic Ocean, from Canada to Brazil, through the United States of America and Mexico. It is found in shallow inshore waters, up tp depths over 70m, among seagrass, sponges, corals and floating Sargassum. In 2009, a specimen of H. erectus was found in the Azores, but further search is required to confirm the existence of a possible established population.

The lined seahorse hunts small live crustaceans and shrimp, like all other seahorses. Their hunting strategy varies with habitat complexity. In locations without aquatic vegetation, this seahorse will actively swim around searching for prey. However, in vegetated habitats, it tend to be more stationary, visually searching for prey while attached to holdfasts. 

Within the breeding season (between May and October), males pair with one female. The seahorse's pair performs a long courtship ritual, where the male rubs its head on the female’s belly, swim together, and tangle their tails around each other. The ritual ends when the two swim towards the surface and the female deposits her eggs in the male’s brood pouch. The male is the one incubating the embryos and providing parental care. After parturition, the male no longer provides any care to the offspring and searches the female for another pregnancy. The female can recognise its pair by olfactory cues.  However, if the pair is separated, the female may search for another male.