Very small species of seahorse and therefore extremely hard to find, unless you know where to look. It has 12 rings on its trunk and 26-28 on the tail and a small or absent anal fin. The trunk is midsize and ends straight, without becoming wider at the tip. On its head it shows a raised, angular coronet. On the trunk and tail it has spikes. It is predominantly white with sometimes yellow or pink patches, and fine red lines on its back, and sometimes tail and head. It shows a lot of similarities with Hippocampus severnsi, but that is predominantly brown.
It has been assessed by the IUCN, but deficient data has been analyzed to claim a status. They are considered to be rare, since they have only been recorded from Indonesia and Papua New Guinea.
Hippocampus pontohi has been observed on the coralline algae Halimeda, as well as on the hydroid Aglaephenia cupressina, but particularly in areas where Halimeda is growing on reef walls. It has been recorded at depths between 11-25 meters, particularly on vertical walls or in rock fissures on current-swept walls where it will tend to occur on the side of the fissure that faces away from the current, but in all cases where there is some upward current.
Seahorses are one of the few animal species where the males brood the eggs in a pouch, where they finally hatch.
Up to 1.7 cm.
It feeds on small crustaceans, which it sucks inside its mouth.
This species has been discovered fairly recently (in 2003) and officially named in 2008, and is most likely often overlooked since it is so small. They are also often mixed up with the similar species Hippocampus severnsi, that is the same size, but brown in color as opposed to the white of Hippocampus pontohi.