A three-spot seahorse that looks like a zebra!

trimac-iseahorse-may2016.jpg

This spectacular specimen of Hippocampus trimaculatus, commonly known as the three-spot seahorse, was spotted by iSeahorse user Anna Pfotenhauer (aka anna18) off the coast of Negros Island in the Philippines.  See the iSeahorse featured observation here.

Those of you familiar with seahorse species will likely quickly ask ‘But isn’t this Hippocampus zebra? It looks like it has the zebra pattern!” - and it doesn’t seem to have the three spots that give it its common name. So what gives? Well, it turns out that colour, patterns and markings in seahorses can vary widely, both within and between species. Therefore these characteristics don't distinguish between species, and may lead to confusion when identifying seahorses. In addition to H. zebra being only found in Australia (it is endemic to there), there are morphological (form and structure) distinctions between the two. Most notably, H. trimaculatus has cheek spines that are hooked-back and a low coronet, whereas H. zebra has more pronounced conical coronet. And so.... morphology provides a much better set of characters to distinguish among species, than colour or patterns.

This becomes important when seahorse management and conservation come into play. For example, Hippocampus trimaculatus is listed as Vulnerable on the IUCN Red List. If we were to mistake a large number of individuals for this species, we may inadvertently and erroneously find that H. trimaculatusis less threatened than is actually the case, and in turn direct less effort towards the recovery of the species.

Thanks again to Anna for her excellent photo observation. We hope that this and other iSeahorse observations lead to more awareness of these magnificent creatures.

Originally posted on iSeahorse.org