Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biologists Discover Giant Crayfish Right Under Their Noses

20.01.2011
Two aquatic biologists have proven that you don't have to travel to exotic locales to search for unusual new species. They discovered a distinctive species of crayfish in Tennessee and Alabama that is at least twice the size of its competitors. Its closest genetic relative, once thought to be the only species in its genus and discovered in 1884 about 130 miles away in Kentucky, can grow almost as big as a lobster.

The researchers found their first specimen under one of the biggest rocks in the deepest part of a creek that has been a (literal) stomping ground for aquatic biologists for at least half a century. The new species is described in a paper in the Proceedings of the Biological Society of Washington.

The new crayfish belongs to the genus Barbicambarus, which in addition to being big is very distinctive. Most notably, Barbicambarus have unusual “bearded” antennae; the antennae are covered with a luxurious fringe of tiny, hair-like bristles, called setae, which enhance their sensory function.

“This isn’t a crayfish that someone would have picked up and just said, ‘Oh, it’s another crayfish,’ and put it back,” said University of Illinois aquatic biologist Chris Taylor, the curator of crustaceans at the Illinois Natural History Survey and a co-discoverer of the new species with Eastern Kentucky University biological sciences professor Guenter Schuster.

“If you were an aquatic biologist and you had seen this thing, because of the size and the setae on the antennae, you would have recognized it as something really, really different and you would have saved it.”

Schuster first learned of the crayfish in 2009 when a colleague forwarded photos from a man who had seen the animal in Shoal Creek, a stream in southern Tennessee that ultimately drains into the Tennessee River. Schuster immediately recognized it as a member of the genus Barbicambarus, and sent the photos to Taylor, his longtime collaborator.

Both men suspected that this was a wayward member of the originally discovered species, Barbicambarus cornutus. B. cornutus had never been seen that far south, but the researchers knew that crayfish have been moved great distances in the bait buckets of itinerant fishermen or by those interested in commercially rearing crayfishes.

“I was leaning to the easiest explanation,” Taylor said.

“Me too,” said Schuster. “That’s been going on for 50 years in the U.S., moving species around, so it would not be a surprise if that was the case.”

The researchers contacted a colleague in Tennessee, who told them that a scientist with the Tennessee Valley Authority, Jeffrey Simmons, had collected a crayfish that looked like the one in the photo – “just a couple of miles from where the original photograph we had gotten was taken,” Schuster said.

That was enough to spur a hastily organized field trip to Shoal Creek.

With two other biologists, Taylor and Schuster scoured the creek for more specimens. After two hours of turning over boulders and kicking up the sediment to flush the crayfish into their seine, the researchers had found nothing out of the ordinary.

“We had worked so hard and long that we were ready to give up and find another site,” Schuster said. “And we saw this big flat boulder underneath a bridge and so we said, ‘OK. Let’s flip this rock, just for the heck of it; this will be our last one.’ And sure enough, that’s where we got the first specimen.” It was a big male, about twice the size of any other crayfish they had seen that day. And it had the characteristic bearded setae.

The researchers found only two specimens that day, a very small haul for nearly three hours of work. The second specimen, a female, was under a large, flat boulder that was too big for one man to lift alone in the current.

In the lab, Schuster quickly realized that the physical characteristics of the new crayfish differed in significant ways from those of B. cornutus. Taylor took tissue samples and compared the specimens’ DNA to that of B. cornutus.

“And the DNA said just what the morphology said: This thing is pretty different,” Taylor said.

And rare. The researchers made several more trips to the area before they were able to collect enough specimens to confirm what they already suspected: The giant crayfish of Shoal Creek was a new species. They named it Barbicambarus simmonsi, in honor of the TVA scientist who had collected the first specimen.

Later trips to the region confirmed that B. simmonsi was also present in the southern reaches of Shoal Creek, just north of where it drains into the Tennessee River in northwest Alabama.

Most people are shocked to learn that there are about 600 species of crayfish in the world, Taylor said, with more than half of those occurring north of Mexico. Alabama and Tennessee are hotspots of crayfish diversity, he said.

The discovery of a new species of crayfish in itself is not unusual, the researchers said. About two new species of crayfish are found every year in the U.S. But the discovery of a large, distinctive new species in a region that had been studied for decades is quite astounding, they said.

“We looked at museum collections around the country,” Taylor said. “There were no specimens in there masquerading under a different species name. No one had found this thing and called it B. cornutus. This thing had not been seen by scientific eyes until last year.”

The fact that a distinct species was overlooked for so long indicates that studies of species diversity in the U.S. are not getting adequate resources, Schuster said.

“We spend millions of dollars every year on federal grants to send biologists to the Amazon, to Southeast Asia – all over the world looking for and studying the biodiversity of those regions,” Schuster said. “But the irony is that there’s very little money that is actually spent in our own country to do the same thing. And there are still lots of areas right here in the U.S. that need to be explored.”

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>