''Ptychidio jordani'', the ratmouth barbel, is a species of freshwater,

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

from the

carp Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. While carp is consumed in many parts of the world, they are generally considered an invasive species in parts of ...

family,

Cyprinidae Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest verte ...

. It is endemic to the

Pearl River The Pearl River, also known by its Chinese name Zhujiang or Zhu Jiang in Mandarin pinyin or Chu Kiang and formerly often known as the , is an extensive river system in southern China. The name "Pearl River" is also often used as a catch-all ...

drainage system, purported records from Taiwan being considered extremely doubtful. It has been a highly sought species for fisheries but the population has declined to such an extent that it is now rarely caught and the damming of its native streams and rivers is now the chief threat to this species. This species is found in fast flowing, clear, streams and rivers flowing over gravel substrates, spawning in rapids. It is a

demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...

species which feeds on molluscs and algae. It is now a protected species in

Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...

but this little known species requires further research to determine how best to conserve it. It grows to a maximum size of 33 cm. The specific name ''jordani'' was applied by

George S. Myers George Sprague Myers (February 2, 1905 – November 4, 1985) was an American ichthyologist who spent most of his career at Stanford University. He served as the editor of ''Stanford Ichthyological Bulletin'' as well as president of the American So ...

in honor of ichthyologist

David Starr Jordan David Starr Jordan (January 19, 1851 – September 19, 1931) was the founding president of Stanford University, serving from 1891 to 1913. He was an ichthyologist during his research career. Prior to serving as president of Stanford Univer ...

in appreciation of his friendship and kindness to Myers.

References

Cyprinid fish of Asia Freshwater fish of China Taxa named by George S. Myers Fish described in 1930 Labeoninae {{Labeoninae-stub