H. Angustus grows to about 8". They are only found on the West coast of Australia in temperate waters. They have brown lines ACROSS the snout that distinguishes them from the other Australian Seahorses, and from H. Histrix. Coloring is found in white, yellow, and orange. They sometimes have a network of finer lines on the body. The lines run halfway around the snout, on the top side sloping diagonally towards the body, and to a lesser degree over the head and parts of the body. They are not at all prickly like H. Histrix. They are bigger than H. Histrix and a bit blotchy in their markings.