Xiurenbagrus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of catfish

Catfish

Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

es (order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Siluriformes) of the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Amblycipitidae

Amblycipitidae

Amblycipitidae is a family of catfishes, commonly known as torrent catfishes. It includes three genera, Amblyceps, Liobagrus, and Xiurenbagrus.-Taxonomy:...

. It includes two species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

.

Taxonomy

X. xiurenensis was first described in 1981 as Liobagrus xiurenensis. However, it was realized that Liobagrus would not be monophyletic

Monophyly

In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...

 with the inclusion of this species, so Xiurenbagrus was erected. The genera Amblyceps and Liobagrus are sister group

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 pair that is, in turn, sister to Xiurenbagrus. X. gigas was described in 2004.

Distribution

X. gigas is known only from the Hongshuihe River which belongs to the Xijiang River

Xijiang River

The Xi River is the western tributary of the Pearl River in China. It is formed by the confluence of the Gui and Xun Rivers in Wuzhou, Guangxi. It then flows east through Guangdong, and enters the Pearl River Delta just east of the Lingyang Gorge in Zhaoqing. The main branch of the Xi flows...

, the largest tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Pearl River

Pearl River (China)

The Pearl River or less commonly, the "Guangdong River" or "Canton River" etc., , is an extensive river system in southern China. The name Pearl River is usually used as a catchment term to refer to the watersheds of the Xi Jiang , the Bei Jiang , and the Dong Jiang...

 basin in China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

. X. xiurenensis inhabits the Pearl River, northward to Lijiang River

Lijiang River

The Li River or Lijiang River is a river in Guangxi Zhuang Autonomous Region, China.-Background:The Li River originates in the Mao'er Mountains in Xing'an County and flows in the general southern direction through Guilin, Yangshuo and Pingle....

 near Guilin

Guilin

Guilin is a prefecture-level city in the northeast of the Guangxi Zhuang Autonomous Region of far southern China, sitting on the west bank of the Li River. Its name means "forest of Sweet Osmanthus", owing to the large number of fragrant Sweet Osmanthus trees located in the city...

, Guangxi

Guangxi

Guangxi, formerly romanized Kwangsi, is a province of southern China along its border with Vietnam. In 1958, it became the Guangxi Zhuang Autonomous Region of the People's Republic of China, a region with special privileges created specifically for the Zhuang people.Guangxi's location, in...

, southward to Zuojiang River near Longzhou, Guangxi.

Description

Xiurenbagrus species have a ventral

Anatomical terms of location

Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...

 mouth. The fin margins are pale. The adipose fin is not confluent with the caudal fin and has a free lobe. X. gigas is the largest species of amblycipitid and grows to about 16.5 centimetre

Centimetre

A centimetre is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of . Hence a centimetre can be written as or — meaning or respectively...

s (6.5 in

Inch

An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...

) SL

Fish measurement

Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...

. X. xiurenensis is a small- to medium-sized amblycipitid, growing to about 10.7 cm (4.2 in) SL.

Ecology

Little is known about the ecology of these fishes. X. xiurenensis is benthic and inhabits streams in the Nanling

Nanling

The Nanling are a group of mountain ranges of southern China, running through Guangxi Zhuang Autonomous Region, Guangdong province, and Hunan province....

 mountain range. The stomach contents have been studied to contain parts of arthropod

Arthropod

An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...

s.