Photo: Shown is a young male Galápagos vermilion flycatcher on Isabela Island. It is not extinct, unlike its close relative, the San Cristóbal Island vermilion flycatcher. Credit: Jack Dumbacher and the California Academy of Sciences Researchers have recommended a taxonomic upgrade to full species status for a subspecies of songbird found only on San Cristóbal Island in the Galápagos. But there's some fine print involved: The bird hasn't been seen since 1987 and it may no longer exist.

The bird, the San Cristóbal Island vermilion flycatcher, is one of two Galápagos subspecies of vermilion flycatcher that a research team has determined should be species all their own. (The other is the more common, and still among us, Galápagos vermilion flycatcher: Pyrocephalus nanus.)

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The researchers -- hailing from the California Academy of Sciences (CAS), San Francisco State University, the University of New Mexico, and the San Francisco Bay Bird Observatory (SFBBO) -- used DNA analysis of a century's-worth of Galápagos bird specimens at the CAS to determine that both birds were genetically distinct enough to be new species.

But it's the San Cristóbal songbird (Pyrocephalus dubius) that is garnering all of the attention.

"A species of bird that may be extinct in the Galápagos is a big deal," said Jack Dumbacher, co-author of a study on the birds and CAS curator, in a statement.

"This marks an important landmark for conservation in the Galápagos, and a call to arms to understand why these birds have declined," he added.

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Twelve subspecies of vermilion flycatcher range widely throughout the Americas and, of course, the Galápagos. The small, stout songbirds (here's what one sounds like singing) are a showy exception to the usually dull colors of other flycatchers. They feed largely on insects such as flies, wasps and beetles.

The missing San Cristóbal vermilion flycatcher has only been known to exist on its island namesake. If it is indeed extinct, the reasons for its disappearance aren't yet known, though rats and flies are potential culprits, say the scientists. Rats will climb trees to eat bird eggs, and flies can kill new chicks. Both pests are doing serious damage to the remaining vermilion flycatcher populations on the Galápagos islands.

"Sadly, we appear to have lost the San Cristóbal vermilion flycatcher," said Dumbacher, even as study co-author Alvaro Jaramillo, SFBBO biologist, allowed a bit of eternal hope to spring: "At the very least," said Jaramillo, "this discovery should motivate people to survey and see if there are any remaining individuals of the species hanging on that we don't know about."

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