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ne look at our factsheet of the month for April 2020 and you may think that this fish needs a good feed but as its specific name suggests, gracilis: meaning graceful or slender, and you get the exact nature of this catfish from the Bagridae family and why it looks like this. T. gracilis was described from specimens collected from the Zhujiang (Pearl River) basin, southern China.

Tachysurus gracilis

There is still ongoing discussions in the scientific fraternity on the validity of the genus name of Tachysurus as the original description of this genera was by La Cepède in 1803 and it depicted a member of the Ariid catfish family. He proposed the name Tachysurus sinensis for a catfish depicted in a Chinese illustration archived in Paris at the Muséum National d’Histoire Naturelle (MNHN). Tachysurus sinensis La Cepède, 1803 is the type species of Tachysurus La Cepède, 1803 (pp. 150, 151) by monotypy. The locality for the illustration is given as China. The only problem with this was the painting looked very much like a Bagrid and not an Ariid species and quite probably Pseudobagrus fulvidraco (Richardson, 1846) or P. nitidus Sauvage & Dabry de Thiersant, 1874.

Of course this story is not as simple as that and if you want to read more on the pros and cons of this argument you can seek out and read the references listed below by López; J. Andrés 2008 and Ng, H.H. & Kottelat, M, 2007. To add to this confussion, Fishbase has this species still listed as Pseudobagrus gracilis and Catalog of Fishes has it as the current status of Tachysurus gracilis Li, Chen & Chan 2005.

Tachysurus gracilis


T. gracilis closely resembles Tachysurus adiposalis and Tachysurus ussuriensis, but differs in having a large elliptical eye (19.8–24.4% HL), a short maxillary barbel not reaching the posterior margin of the eye, a lightly serrated posterior edge on the second dorsal spine, a caudal fin slightly emarginated with upper lobe slighter longer than lower lobe (see caudal fin shapes below), frontal concave with a smooth surface, and supraoccipital process short (far from the first basal bone of the dorsal spine).

Pseudobagrus gracilis

None

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Asia: Beijiang and Xijiang (West River) River basins, southern China. Type locality: China: Guangxi Province, Guilin City, Zhujiang basin, Lijiang drainage, 29º55'23 N, 118º28'12 E.

17cm (6¾ins)

21-24°C (69-75°F)

6.0-7.0.

Large elliptical eye (19.8–24.4% HL), a short maxillary barbel not reaching the posterior margin of the eye, a lightly serrated posterior edge on the second dorsal spine, a caudal fin slightly emarginated with upper lobe slighter longer than lower lobe, frontal concave with a smooth surface, and supraoccipital process short (far from the first basal bone of the dorsal spine).

The dorsum is dark grey, and the underside is whitish with yellow in all fins in some specimens. Alcohol-preserved specimens are greyish-brown dorsally, and flanks have a lighter tinge.

This is a primarily a cool water catfish so placing the tank in a centrally heated house would suffice but there are also reports that this catfish is also happy at temperatures of between 23-26°C (72-79°F) so a very variable temperature range does not worry this Bagrid at all. Providing a good current in the aquarium will suit this catfish. Not too much of a problem catfish as long as you don't house them with smaller species as being a Bagrid they will do what the vast majority of Bagrids will do "chase and eat them". Keep them in a group and they will get on fine together as long as you give them plenty of room and hiding places for each individual.

In their natural habitat these fish form small breeding colonies by making burrows or depressions on the bottom near the shore. The eggs are guarded by the male.

As with most other species of catfish the males tend to be more slender than the females. It would appear also that the male can be determined by the papillae just prior to the anal fin, a feature found in other Bagridae.

Will accept most prepared foods such as flake, tablets, live and frozen tubifex and bloodworm.

Caudal fin: The tail.
Maxillary: Pertaining to the upper jaw. (maxillary barbels).
Supraoccipital process: Unpaired bone at the back of the skull, usually with a crest.

Tachysurus: tachys, swift; oura, tail, referring to the presumed agility of T. sinensis based on its “long and nimble” tail (translation).
gracilis: Latin for slender. The species is named for its elongated and thin body form.

Ferraris, C.J. Jr., 2007. Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types. Zootaxa 1418:1-628.
Jie Li, Xianglin Chen & Bosco P.L. Chan; (2005) A new species of Pseudobagrus (Teleostei: Siluriformes: Bagridae) from southern China. Zootaxa 1067: 49–57.
López; J. Andrés Case 3455 Pseudobagrus Bleeker, 1858 (Osteichthyes, Siluriformes, BAGRIDAE):proposed conservation. Bulletin of Zoological Nomenclature 65(3) September 2008.
Ng, H.H. & Kottelat, M; The identity of Tachysurus sinensis La Cepède, 1803, with the designation of a neotype ( Teleostei: Bagridae) and notes on the identity of T. fulvidraco (Richardson, 1845). Electronic Journal of Ichthyology November, 2007 2: 35-45.

Photo Credits

Top Image: ©  
Second Image: © Zhou Hang
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