Miguel Correia pointed at the seafloor. I stared and shook my head. He jabbed a gloved finger at the spot. I swam closer and stared harder. Sand. Algae. Rocks. A spiral of sea cucumber poop. I exhaled a swarm of bubbles in frustration.
And then, suddenly, there it was, tucked into the seaweed right where I’d been looking: a three-inch-tall, long-snouted seahorse, Hippocampus guttulatus, muddied yellow with a smattering of dark freckles and a mane of skin filaments. Later that dive I spotted (also with help) its short-snouted cousin, Hippocampus hippocampus, the other seahorse native to this coastal lagoon in Portugal called Ria Formosa.
Every continent but Antarctica has varieties of these fabled fish in its coastal waters. Worldwide, scientists recognize 46 species, the smallest no bigger than a lima bean, the largest the size of a baseball glove. And that number is likely to rise: Four new species were named in just the past decade.