Newly discovered / described species 2016

The Alabama sturgeon lives! Feared extinct, fish's DNA rediscovered in Alabama River

The Alabama sturgeon lives!

Scientists have found evidence that the state's namesake sturgeon species, which many feared had slipped into extinction, persists in multiple locations in the Alabama River.

Scientists have not laid hands on an Alabama sturgeon since 2007, when state biologists captured a single fish.

In Endangered Species Act documents from 2010, the U.S. Fish & Wildlife Service wrote, "with only three documented occurrences in the last ten years, the Alabama sturgeon is undoubtedly one of the rarest freshwater fishes on the planet."

But Alexis Janosik, an assistant professor at the University of West Florida, and Steve Rider, a biologist with the Alabama Department of Conservation and Natural Resources, detected the fish's DNA in multiple water samples collected from the Alabama River in 2014 and 2015.

Fish, like all animals including humans, constantly shed their DNA, in the form of everything from scales to eggs to bodily waste. And that DNA persists in the water column at the cellular level for several weeks, depending on exposure to sun, high temperatures, and other factors.

Much like a crime scene investigator swabbing surfaces for blood, hair or fingerprints, scientists are now able to use state of the art genetic techniques to search for organisms living in lakes and rivers.

The team collected 130 one-liter water samples up and down the Alabama River. Janosik said they detected traces of Alabama sturgeon DNA in about 17 percent of the samples.

"These data, we are confident the species is there," Janosik said. "And it tells us it was there relatively recently. Somewhere between 8 and 40 days from when we collected the samples. In Alabama streams, things degrade very quickly, its warm. So, we know that relatively recently we've had the fish swimming around."

The discovery is the most hopeful sign in a decade that the species survives.

Read more: The Alabama sturgeon lives! Feared extinct, fish's DNA rediscovered in Alabama River | AL.com
 
Gonzaga, Diego Rafael, Moraes, Lucas, Neto, Luiz Menini and Peixoto, Ariane Luna. (2016). Rediscovery, considerations about type locality and conservation of Rhipsalis agudoensis (Cactaceae) from the Brazilian Atlantic Forest. Phytotaxa 278(1): 74-78. [Abstract]
 
From the "recently extinct thread":

Surroundx said:
Sighting of Yangtze River Dolphin Believed Functionally Extinct

Amateur investigators have reported spotting what they believe to be a baiji dolphin in a stretch of the Yangtze river in eastern China. The animal was declared “functionally extinct” in 2006 after researchers from six countries failed to find a single dolphin, and concluded there were too few left to save the species.

At around 9:20 a.m. on Tuesday, the team of 11 saw what looked like a dolphin in the Yangtze river close to the city of Wuhu, in Anhui province, while on a one-week expedition to look for the animal. The dolphin jumped out of the water in easy view of one of the team’s boats, which was around 100 meters away. People on the team’s second boat, which was around 300 meters away, also saw the animal.

According to Song Qi, the leader of the expedition, the animal breached the surface of the water more than once, allowing the team to get a good look at it. “I saw most of the body, and the second time around I saw its mouth and head,” Song said in a telephone interview with Sixth Tone. Song was on the second boat which was further away, but team members on the first boat got a better look at the creature. “The front boat saw it three times,” Song said. Song estimated that altogether six people on the investigation team saw the animal.

Read more: Sighting of Yangtze River Dolphin Believed Functionally Extinct | Sixth Tone
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