Xanthichthys mento, adult male, seen at Flora & Fauna
Marineaquaristik, Wrist, Germany. Photo: I. Krause
The Crosshatch Triggerfish
Xanthichthys mento
In these Rarities profiles we often focus on tiny creatures, such as dwarf gobies or symbiotic shrimps, which
appear to be somewhat rare on account of their cryptic
behavior. But in this issue, I would like to present a rarity
whose imposing appearance will cause the hearts of big-fish fans to beat faster: Xanthichthys mento, the Crosshatch Triggerfish.
The members of the triggerfish family can be roughly
divided into two groups. Those in one group have point-
ed mouths armed with powerful teeth and specialize in
feeding on hard-shelled invertebrates, while those in the
other group prefer to feed on plankton, as indicated by
their upward-pointing mouths. The plankton-feeding
species are appreciably better suited to aquarium main-
tenance than their invertebrate-eating relatives, and
those of the genus Xanthichthys are some of the easier
triggerfishes. For this reason the Bluechin Triggerfish,
Xanthichthys auromarginatus, is seen fairly frequently in
the aquarium trade and is popular with aquarists. The
closely related X. mento hardly ever turns up on import-
ers’ stock lists and is predictably expensive when it does.
Compared to a colorful male Crosshatch Triggerfish,
even the much-cited Flaming Prawn Goby (Discordipin-
na griessingeri) is a bargain; large rarities are even more
expensive than small ones. Given the extensive distribu-
tion of the species (Western Pacific: southern Japan, the
Ryukyu Islands, Hawaii; Eastern Pacific: southern Cali-
fornia, Clipperton, Galapagos Islands), the high price
seems difficult to justify, but the reason may be the re-
moteness of some of the regions in question.
