New ‘walking’ fishes discovered in Gulf oil-spill zone

Pancake batfishes may be getting oiled before they get named

Two new fish species — with pancake-flat bodies, wiggling lures on their faces, and elbowed fins for “walking” on the seafloor — have been discovered in the path of spewing Gulf of Mexico oil.

The newly discovered Louisiana pancake batfish, small enough to fit in the palm of one hand, had not even had its official Latin name published when the Gulf oil spill threatened its entire habitat. Courtesy of AMNH

One of these pancake batfishes lives in the northern Gulf where oil is already spreading from the Deepwater Horizon blowout, says ichthyologist Prosanta Chakrabarty of Louisiana State University’s Museum of Natural Sciences in Baton Rouge, a codiscoverer of the species.

Chakrabarty calls this narrowly distributed species the Louisiana pancake batfish. Its full scientific name, in the genus Halieutichthys, hasn’t even been published yet. The oil’s impact on the soon-to-be new species isn’t clear. ”All we can say is that its habitat is threatened,” Chakrabarty says.

The other newly identified pancake batfish has a somewhat broader range. Yet all pancake batfishes, now three species in total, live in water that could be fouled if Gulf oil heavily taints the Loop Current off Florida’s west coast.

Louisiana pancake batfish grow only about “that big,” Chakrabarty says, making a circle of his thumb and forefinger. They’re as thick as an exceptionally fluffy pancake. Fins that work almost like stubby arms prop them up or let them waddle along the bottom.

Unlikely as it may sound, these little squashed-looking fishes are anglerfish, a group most people know from nature documentaries depicting these chunky, fanged creatures of the deep ocean. Anglerfishes get their name from projections that dangle somewhere in the vicinity of their mouths and invite overly curious passersby in for lunch. Pancake batfishes have a lure too, a stubby projection that twitches where a nose would be on a mammal face.

Deep-sea anglerfish evolved from ancestors living in shallower water, Chakrabarty says. Studying today’s pancake batfish, which all live in roughly the top hundred meters of the sea, could offer insights into the ancient transition to the depths.

A first inkling of the new species arose when colleague Hsuan-Ching Ho of the Academia Sinica in Taipei, Taiwan, was visiting Chakrabarty and noticed that specimens of what was supposed to be one species actually looked like more than one. Trawling expeditions produced new specimens that confirmed consistent differences in traits such as tiny projections that roughen skin. Ho and Chakrabarty joined John Sparks of the American Museum of Natural History in New York City to write a formal description to appear in the Journal of Fish Biology.

The pancake batfish have suddenly become the new face of imperiled sea life in the oiled Gulf. “I just hope people will still care next year,” Chakrabarty says.

Pancake batfishes are just one example of the rich life beneath the surface of the Gulf of Mexico. As the oil spreads, Dean Grubbs of Florida State University’s Coastal & Marine Laboratory in St. Teresa says he’s thinking of the many ecological treasures at risk that aren’t making the news nightly. In the Gulf lies one of the largest seagrass beds in the world, he points out, as well as spawning grounds for smalltooth sawfish.

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.

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