My Marine Tank.

Dear Dean:

Yes, sir, quite a few hobbyists here in the USA keep nano tanks as well, especially the reef keepers. It’s good to hear that you have an excellent guide book on nano tanks to follow and the accelerated maintenance schedule you are following is very important because the water quality can deteriorate very quickly in a small aquarium.

I would be happy to help identify what type of seahorse you have, Dean. If it’s an Indonesian seahorse, then it’s not the same species as Mustangs or Sunbursts (Hippocampus erectus), which are found along the eastern seaboard of the U.S., but I would certainly be happy to send you some photographs of Mustangs, Sunbursts, and SunFires for you to compare with your yellow seahorse. You can contact me off list at the following e-mail address, and I will send you a reply with lots of photographs: [email protected]

My best guess is that your yellow Indonesian seahorse may be Hippocampus barbouri or perhaps the yellow color phase of Hippocampus kuda. But you can’t really attempt to identify seahorses on the base of their color pattern alone, since that is such a variable characteristic. If you can possibly send one or more digital photographs of your seahorse to my personal e-mail address, it will make an identification much easier. I will be able to study the size and shape of the seahorse’s coronet from a good picture and provide you with an educated guess based on its morphometrics. Do you know if your seahorse is wild or captive bred and raised, Dean?

I can understand how the language barrier presents a problem for you, Dean, and it sounds like you have hit upon an ingenious way of overcoming such problems by looking up photographs of the specimens we have discussed online and then showing the pictures to your pet dealer so he knows exactly what we are talking about. That’s an excellent way to proceed.

That’s very interesting to hear about the unusual fish that have been turning up in Indonesia following in the aftermath of the tsunami. The glassy white seahorse with no eyes definitely sounds like something new to science, Dean. All of the known seahorse species have well-developed independent eyes. The basic structure of the seahorse’s eyes is quite similar to our own: a spherical oculus having a cornea, lens, and a retina containing both rods and cones. The primary differences are that in Hippocampus the highly mobile, rotary eyes are mounted on the sides of the head, are independently operating, and have a differently shaped lens (spherical rather than lenticular or biconvex) that cannot change its form.

So it would be most unusual indeed for a sightless species of seahorse to have developed, and if the glassy white seahorse that Seaworld in Jakarta has collected is naturally blind and has not merely lost its eyes to accident or injury, it is a unique specimen and I have never heard of the like. Animals will sometimes lose their organs of sight when they live in an environment where vision is useless for untold generations, such as deep-sea fish that live in the abyss where no light penetrates or cave-dwelling animals that never see the light of day. Under such conditions, eyes are useless and may be lost or reduced to nonfunctional vestigial organs over the eons. Pigmentation is also useless in such environments and is therefore lost for the same reason, so that many deep-sea animals are transparent and many cave dwelling creatures (e.g., blind cave fish, salamanders, cave crickets and centipedes) become a translucent white in coloration. So if the reports of a glassy white seahorse with no eyes are accurate, it’s tempting to think it could be a new species of deep-sea seahorse that was dredged up following the tsunami or a species accustomed to living deep within limestone caves that was washed out of its natural habitat. Such a creature is unheard of and I would love to see photographs if you can possibly obtain them, Dean!

Best wishes with all your fishes, sir! I think it’s a very sensible idea to upgrade to a larger seahorse tank when you can manage it.

Respectfully,
Pete Giwojna