''Leiarius'' is a genus of long-whiskered catfishes native to South America. Most of the genus' species are found in the

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

hobby as ornamental fish.

Species

There are currently four recognized species in this genus: * '' Leiarius arekaima'' (

Jardine Jardine is a surname. Notable people with the surname include: * Al Jardine (born 1942), member of the Beach Boys * Alexander Jardine (Medal of Honor) (1874–1949), American Medal of Honor recipient * Antonio Jardine (born 1988), NCAA college bas ...

, 1841) * '' Leiarius longibarbis'' ( Castelnau, 1855) * '' Leiarius marmoratus'' ( Gill, 1870) (Marbled catfish, Marbled pim) * '' Leiarius pictus'' (

Müller Müller may refer to: * ''Die schöne Müllerin'' (1823) (sometimes referred to as ''Müllerlieder''; ''Müllerin'' is a female miller) is a song cycle with words by Wilhelm Müller and music by Franz Schubert * Doctor Müller, fictional character ...

Troschel Franz Hermann Troschel (10 October 1810 – 6 November 1882) was a German zoologist born in Spandau. He studied mathematics and natural history at the University of Berlin, where he was awarded his doctorate in 1834.Beolens, Bo; Watkins, Michael; ...

, 1849) (Marbled sailfin catfish, Sailfin pim)

Anatomy and physiology

''L. marmoratus'' can reach a little more than 100 centimetres (39 in) TL and has a maximum published weight of about 12

kilogram The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce worldwide, and is often simply called a kilo colloquially ...

s (26 lb). ''L. pictus'' grows to 60 cm (24 in) TL. These two species can be easily confused. The body of ''L. pictus'' is brown with darker brown spots, with a paler ventral coloring. In juvenile ''L. pictus'', two parallel, pale bands curve from the dorsal fin down the body towards the caudal fin. In young fish of both species, the maxillary barbels are very long and ringed with black and white. As both of these species grow, their barbels will shorten in proportion to their size, and the caudal fin lobes, which are rounded in the young, become much more pointed. As ''L. marmoratus'' grows older, it darkens and its dark spots develop into a marbled pattern. Both species have a large, sail-like dorsal fin. There are no external sexual differences.

Range and distribution

''L. marmoratus'' is found in the Amazon,

Essequibo Essequibo is the largest traditional region of Guyana but not an administrative region of Guyana today. It may also refer to: * Essequibo River, the largest river in Guyana * Essequibo (colony), a former Dutch colony in what is now Guyana; * Esseq ...

, and Orinoco River basins. On the other hand, ''L. pictus'' is only found in the Amazon and Orinoco River basins.

Ecology

''L. marmoratus'' inhabits riverbeds, deep wells, and lakes. Young or sub-adults form large schools. This species prefers to lay over rock and tree trunks during the day, being more active at sunrise, sunset, and night.

Importance to humans

In aquaria

Both ''L. marmoratus'' and ''L. pictus'' are ornamental fish kept as pets in the

hobby. They have a voracious appetite and can grow rapidly, and therefore should be kept in a very large aquarium. These fish are peaceful towards other large fish. Some sort of retreat to allow these fish to hide during the day is required. These fish get very large and are not recommended for the average aquarist.

References

Bibliography

* {{Taxonbar, from=Q6519053 Pimelodidae Fish of South America Fish of the Amazon basin Catfish genera Taxa named by Pieter Bleeker Freshwater fish genera