Stomatopod Care and Rearing

Smart Shopping: When is a Clown Mantis not a Clown?

This is a short warning to those people interested in purchasing mantis shrimps from commercial sources, and deals with the particular style of categorizing mantis shrimps that is prevalent (at least in New Jersey, USA, and probably in New York City) in these establishments. It is based on my recent experience in many of the stores in this area.

The first thing you should note is that most LFS in the area classify all mantis shrimps into basically three groups: the smallest species are usually called "rock mantis shrimps", and the commercial demand for these critters is practically nil; medium sized and large specimens that are an almost uniform dark green color are almost always termed Squilla mantis; and medium sized to large specimens which have mottled marking on their raptorial appendages and a relatively more flamboyant body color are almost always called "clown mantis shrimps", which the LFS "manuals" seem to label as Odontodactylus scyllarus. The most expensive, of course, are the so-called "clown mantis shrimps", while the smallest specimens are pretty much a gimme.

The problem with this classification scheme is that it is mostly, to put it mildly, wildly wrong. The specimens that I have seen that are labeled "Squilla mantis" (an old designation that is no longer in active use in the scientific literature) are always of the smasher variety (and not spearers, which Squilla mantis were). More importantly, some LFS and their suppliers sell mantis shrimps that are not Odontodactylus scyllarus as "clown mantis shrimps." These smashers, which admittedly are quite colorful, again look to be Gonodactylus or a close relative (in my case, a mantis shrimp of the closely-related genus Gonodactylaceus). This is an honest mistake, and not meant to deceive people, but be warned anyway that what you may at first believe to be Odontodactylus is actually not an individual of that species.

I'm definitely not a taxonomist, and therefore far from an expert in such matters, but here's my take on how to easily tell one from the other.

1. The first way to tell Odontodactylus from the more common Gonodactylidae family is by looking at the outermost segment (the dactyl) of the critter's raptorial appendages. The Gonodactylidae have NO teeth in this segment, whereas Odontodactylus appendages are armed with several teeth.
2. The second way to tell them apart is by looking at the animal between the two compound eyes (preferably from above). The Gonodactylidae have a somewhat long and noticeable SPINE projecting between the two compound eyes, whereas Odontodactylus does not have such a structure projecting from its rostrum.
3. I also figure you can use the shape of the eyes from above as a general take on whether it's Odontodactylus or from the Gonodactylidae. Odontodactylus has ROUNDED looking eyes from above, whereas the latter have more OBLONG, elongated cylinders for eyes.

Hope this helps for those who are looking for an Odontodactylus scyllarus specimen.

banyanwanderer (Airlan).

Web Site Author: A. Sunjian
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