Spined loach
Otolith description
The general shape of the otoliths is square. The otolith is nearly featureless, with a sulcus that is not well developed and an ostium and cauda that are not distinguishable. The sulcus is square and closed and covers about of the surface of the otolith. The surface of the inside, outside and the margins are smooth. The otolith is thick and convex at both inside and outside. The rostrum is rounded, while the antirostrum is indistinct. Spined loach is a small fish and otolith length does not exceed 1 mm.
Otoliths of spined loach can be mistaken for eroded ammodytidae otoliths. Otoliths of ammodytidae have a better developed sulcus that runs diagonally. Otoliths of ammodytidae are thick, though not as thick as spined loach otoliths, since only the outside is convex. Otoliths of ammodytidae are often larger than spined loach otoliths, only otoliths of transparent goby Aphia minuta and crystal goby Crystallogobius linearis are of the same size as spined loach otoliths. However otoliths of these two species are much rounder and thinner than spined loach otoliths.
In eroded otoliths the sulcus is not visible anymore.
Fish length and distribution
Spined loach can grow up to 13 cm. Spined loach is a freshwater fish that is found in slow-flowing or stagnant waters on muddy bottoms. It spawns from April to June (Wheeler, 1978, Nijssen and De Groot, 1987, De Nie, 1996)
It is a locally common fish throughout Europe.
Sample origin
Central part of the Netherlands.