Dwarf Seahorse

Like other seahorses, the dwarf seahorse has a head angled at right angles to its body and swims upright using its dorsal fin to propel it and its pectoral fins to steer. It grows to an average length of 2 and 2.5 cm (0.8 and 1.0 in), with a maximum length of 5.0 cm (2.0 in). The dwarf seahorse can live up to 2 years, but most commonly live around 1. It can be found in colors of beige, yellow, green, and black and may have white speckles, dark spots or protrusions and is well-camouflaged, the coloring usually matching the gorgonian on which it is typically found. It can change color. It has been observed that this seahorse changes color for various reasons such as camouflage, reaction to an attack, due to an illness, or during mating.

H. zosterae can be distinguished from other western Atlantic species such as H. reidi and H. erectus thanks to its number of fin rays. This species possesses from 10 to 13 dorsal and pectoral fin rays, and 9 to 10 trunk rings. Fully grown H. zosterae adults are usually smaller than these two other species.

H. zosterae are found on the western end of the Atlantic Ocean, precisely in the coastal Gulf of Mexico, Bahamas, Bermuda, the Florida Keys, Florida's east coast, Old Tampa Bay, Lemon Bay, Pensacola, and Texas. They are restricted almost totally to seagrass microhabitats in shallow water, particularly in association with seagrasses of the genus Zostera. They are most common in bays during periods of high salinity, in coral reefs, floating vegetations, and between roots in mangrove swamps. They often live as a pair, sometimes alone. Males are rather sedentary and live in a small home range of about 1 square metre (11 sq ft), whereas females roam on other males' territory, around a hundred times larger than theirs.

The dwarf seahorse is a lie-in-wait predator, feeding on living prey, including small crustaceans such as amphipods, small shrimps, other small invertebrates, and fish fry. Once their target is fixed, the hunter stretches towards it and sucks it through its snout. Food progresses through the digestive system rapidly, causing the nutrients to be ill-absorbed. This is the reason seahorses require large amounts of food to survive. These creatures can consume up to 3,000 brine-shrimps per day.