Order:	Cypriniformes
Family:	Cobitididae
Genus and species:	Cobitis taenia

William Yarrell (1836) in "A History of British Fishes":

THE SPINED LOCHE. GROUNDLING.

Botia	tænia,	J. E. Gray, Zool. Misc. p. 8.
Cobitis	"	Linnæus. Bloch, pt. i. pl. 31, fig. 2.
"	"	Berkenhout's Syn. 3rd edit. vol. i. p. 79.
"	"	Spinous Loche,	Penn. Brit. Zool. vol. iii. p. 381.
"	"	Groundling,	Turton, Brit. Faun. p. 103, sp. 90.
"	"	"	Flem. Brit. An. p. 189, sp. 70.

Generic Characters. - Body ovate, lanceolate, compressed, with small scales ; head and operculum naked, with a large spine just behind each nostril ; mouth small ; nose produced; dorsal fin moderate, medial, opposite the ventral fins ; anal fin short.

I HAVE adopted the generic distinction proposed by Mr. J. E. Gray as it applies to one European species, and to the first eight out of the twelve species described by Dr. F. B. Hamilton, in his account of the Fishes of the Ganges, pages 350 to 359. The spine, which is forked and movable, situated behind the nostril and below each eye in the species of the genus Botia, is an organic difference formed by the suborbital bone, which distinguishes them from the unarmed species of the old genus Cobitis.
The Spined Loche is much more rare than that last described. Berkenhout, in his Synopsis of the Natural History of Great Britain and Ireland, says it is found in the Trent, near Nottingham ; Dr. Turton, in his British Fauna, states that it inhabits the clear streams of Wiltshire ; and the Rev. Leonard Jenyns has found it in the Lode, a small river in Cambridgeshire, which runs into the Cam. Its habits are but little known, or have not been distinguished from those of the more common Loach. It is called Groundling from its habit of lurking under stones in search of larvæ and insects. Bloch says it spawns in April or May, and deposits its ova among stones on the bottom. It seldom exceeds three inches in length. By the kindness of Mr. Jenyns, I possess two specimens from the Lode, from one of which the representation, of the natural size, at the head of this article was taken. The fin-rays in number are -

D. 8 : P. 9 : V. 7 : A. 6 : C. 15.

The form of the body is still more elongated, slender, and compressed, than that of the Loach ; the nose more pointed ; the mouth and the eyes smaller in proportion ; the pectoral fin longer and narrower ; all the fins occupying the same relative situation. The colours are similar, both of the body and fins; but a row of dark brown spots ranged along the side are the most conspicuous.

Alwyne Wheeler (1969) in "The Fishes of the British Isles and North West Europe":

Spined Loach

Cobitis taenia Linnaeus, 1758

NAMES Fr. Loche de rivière; Du. Kleine Modderkruiper; Ge. Steinbeisser; Da. Pigsmerling; Sw. Nissöga.

IDENTIFICATION The body is elongate, but strongly compressed laterally, with minute scales. The head is small, with six short barbels around the small mouth, four at the snout tip and two at the corners of the mouth. The small dorsal fin is at about the mid-point of the body. A strong double-pointed spine, in front of and below the eye, points backwards and is often retracted into a skin fold. Grows to 4½ in (11.5 cm), rarely to 5½ in (13.5 cm).
The head and body are light brown, the sides straw-coloured, the belly yellow. The fins are brown spotted, as is the body, the spots tending to form a broken line along the back. Along the midline a series of ten to nineteen rounded or quadrangular dark brown spots run from head to tail, sometimes merging into a wavy line.
D. 10-12; A. 7-9.

BIOLOGY This loach is found in slow-flowing and stagnant waters with a sandy or muddy bottom, in which it lies buried. Several specimens have been caught entangled in the filamentous algae known as 'blanket weed', which suggests it may also burrow into the mass of weed during day-time. It is mainly nocturnal, and this and its burrowing habits, results in its being regarded as extremely rare and local. Its exact distribution in the British Isles is not well known.
It spawns from April to June, depositing its eggs on plants and stones. The pectoral fin is longer and its second ray is thicker in males than in females. The males also have a scale-like projection at the base of the second pectoral ray in its inner face.
The spined loach is said to eat small bottom-living animals and vegetable matter, but no detailed assessment of its food seems to have been undertaken.
It possesses no economic value, but makes a pleasant, if rarely seen, aquarium fish. Like the weatherfish, this loach is able to utilise atmospheric oxygen when that in the water becomes depleted.

DISTRIBUTION

Subspecies in Spain, northern Italy and Morocco.