Denise’s pygmy seahorse (Hippocampus denise).
Pygmy seahorses are among the most well camouflaged species in the oceans, being very difficult to spot amongst the gorgonian coral they live in. Hippocampus denise is tiny, growing only to a total length of 1.5 cm (5/8 inch). It is orange and resembles the pygmy seahorse, Hippocampus bargibanti, though its tubercles are less distinct (From Widipedia).
Shot with a Canon 5D Mark III, 100mm lens in Nauticam housing. Lembeh strait, North Sulawesi, Indonesia. Feb/2013.
Diving with NAD lembeh resot. nad-lembeh.com