News / Species Spotlight / Species Spotlight - Lesser Known Aquarium Fishes of the Eastern Pacific (Part One) (08/17/17)

Species Spotlight - Lesser Known Aquarium Fishes of the Eastern Pacific (Part One)

Lesser Known Aquarium Fishes of the Eastern Pacific (Part One)
The reef fishes available to marine aquarists tend to come from just a couple geographic locations. In the West Atlantic, we get a sparse selection of popular species, like the Royal Gramma, the Queen Angelfish. and the Yellowhead Jawfish. The offerings are far more diverse in the Indo-Pacific, with the fisheries in this region providing the vast majority of the species seen in captivity. Several major fish groups familiar to aquarists (Amphiprion, Cirrhilabrus, Zebrasoma, Siganus, Pseudochromis, Pseudanthias) are only found here.

But there are other parts of the world with their own unique species of reef fish which seldom reach the aquarium market. This is certainly true for Western Africa, whose limited reef fauna is especially uncommon. Today well be focusing our attention towards a different corner of the globe, the Eastern Pacific Ocean. In particular, well be investigating some of its lesser-appreciated fishes.

In comparison with the enormous biodiversity found in the Coral Triangle, the Eastern Pacific has a rather paltry selection to whet the aquaristic appetite. Some of the more frequently seen examples include the Barnacle Blenny (Acanthemblemaria hancocki), the Catalina Goby (Lythrypnus dalli), the Bluespot Jawfish (Opistognathus rosenblatti) and the Paddlefin Wrasse (Thalassoma lucasanum). The Passer Angelfish (Holacanthus passer) is an underappreciated gem found only on these reefs, and the almost mythically rare Clarion Angelfish (H. clarionensis) is one of the true holy grails for collectors of rare reef species. But, for those looking to dig a little deeper, the Eastern Pacific has quite a few more endemic fishes worth checking out

Blackfin Soapfish (Rypticus nigripinnis)

Soapfishes are not everyones cup of tea. While there are some undeniable beauties in the group, many are rather somber in appearance. Rypticus nigripinnis falls somewhere in the middle. It sports a rather attractive spattering of golden spots along the flanks, which contrast quite nicely against the dark reticulations which separate them. As this fish matures, these dark lines spread further, eventually darkening some of the juvenile patterning. With a maximum size of just over a foot in length, this is an ideal choice for larger fish-only systems, provided tankmates are relatively peaceful. Soapfish have earned their common name thanks to the large quantities of thick, sudsy mucus they can excrete when stressed, and within this mucus is a potent toxingrammistin. Careful acclimation is required and aggressive species are best avoided, but, aside from this issue, Rypticus is an undemanding fish in an aquarium, accepting most any meaty food offered.

Wounded Wrasse (Halichoeres chierchiae)

Early on in life, the Wounded Wrasse looks fairly unremarkable. Juveniles are a blotchy white and brown, while females develop a busy pattern of red scale margins that brings to mind a less-vibrant version of the Christmas Wrasse. But, as this fish matures into the male sex, its appearance intensifies dramatically. The creamy base colors of youth give way to a deep green hue in terminal male specimens, with the throat darkening into a sumptuous shade of yellow. And, as if to add a little panache to an already lovely labrid, bright stigmata of black and red appear along the midbody, giving this species its namesake wounds. Youll find H. chierchiae all along the Eastern Pacific, from Mexico to Peru. Mature males top out at around eight inches, making this a suitable choice for larger reef aquariums, though, as with most larger wrasses, smaller crustaceans may be on the menu.

Palenose Moray (Echidna nocturna)

The Echidna morays are probably the single most popular group of eels in the aquarium trade, and for good reason. These tend to be small, peaceful, easily fed, and attractively patterned. In the Eastern Pacific, we find a pair of species. Theres the ubiquitous Snowflake Moray, found all the way west to the Red Sea, and theres the Palenose Moray, which is entirely restricted to this region. Perhaps because of the popularity of its more commonly available relatives, we seldom get to see this eel, but Echidna nocturna has much to offer to the discerning fish collector. Its beauty is far more subtle than the gaudy markings seen in its snowier cousin. The body is a dull, earthy brown, enlived to great effect by a constellation of small, white spots spread across the sides. Reaching a little over two feet in length, this is an ideal choice for the home aquarium.

Spotted Sharpnose Pufferfish (Canthigaster punctatissima)

The sharpnose pufferfishes (AKA tobies) of the genus Canthigaster are a diverse and widespread group in the worlds tropical waters, with dozens of species found everyone from shallow reefs to silty lagoons to rocky, mesophotic habitats. Most of these occur in the Indian and West/Central Pacific, with just a handful found in the Atlantic, but there is one lonely member to be found in the Eastern Pacific, C. punctatissima. The scientific name of this species translates roughly as small spotted and refers to the numerous white polka dots that cover every inch of its wee little body. It belongs to a group of closely related species which are spread across the Indo-Pacific, including the Honeycomb Pufferfish (C. janthinoptera) and the White Spotted Pufferfish (C. jactator), both of which have considerably fewer and larger spots. Though every bit as beautiful as its siblings, relatively few specimens of the Spotted Sharpnose Pufferfish find their way into the hands of aquarists, making this an intriguing and unorthodox addition to any aquarium.

Eyebrow Barnacle Blenny (Ekemblemaria myersi)

The Eastern Pacific is awash in the small blenny-like fishes of the family Chaenopsidae, with 35 recognized species, all of which occur only in this region. These differ from the true blennies in having more spines than rays in the dorsal fin, as well as discrepancies in the structure of their teeth. This latter trait hints at a major ecological difference between the two groups, as the chaenopsids feed on zooplankton, rather than the algae diet of most blenniids. Relatively few chaenopsids in the Eastern Pacific get collected for aquarists. Certainly the most popular is Acanthemblemaria hancocki, known commonly as the Barnacle Blenny. This piscine pipsqueak has endeared itself thanks to its exuberance come feeding time, but theres a lesser-known relative which also shows up on occasion, the Eyebrow Barnacle Blenny (Ekemblemaria myersi). This species grows a little bit larger (just under 3 inches when fully grown) and sports an interesting zebra-like pattern of stripes, as well as more-feathery cirri above the eyes. In the Eastern Pacific, good fishes do come in small packages.