In this article, we will explore the topic of Clarias in depth, examining its meaning, impact and relevance in today's society. From its origins to its current evolution, we will immerse ourselves in a detailed analysis that will allow us to understand the importance of Clarias in different areas of daily life. Through different perspectives and approaches, we will address its implications at both an individual and collective level, highlighting its influence in various sectors. Likewise, we will examine the role that Clarias plays in the current context, providing a comprehensive vision that will allow the reader to understand its importance and impact in the contemporary world.
Clarias has been found to be paraphyletic. A species of Heterobranchus (H. longifilis) clusters deeply inside the Clarias group.
Distribution
They are found in inland waters throughout much of the Old World, and are one of the most widespread catfish genera in the world. The genus is found in Southeast Asia and East Asia westwards through India and the Asia Minor to Africa. The diversity of these catfishes is highest in Africa. Some (notably the walking catfish) have become pest species where they have been accidentally introduced, and particularly in Cuba, where their introduction was intentional.
Description
Clarias species are recognized by their long-based dorsal and anal fins, which give them a rather eel-like appearance. These fish have slender bodies, a flat, bony head, and a broad, terminal mouth with four pairs of barbels. They also have a large, accessory breathing organ composed of modified gill arches. Also, only the pectoral fins have spines.
Species
There are currently 62 species recognized in this genus:
Many of the species are of great economic importance in both fisheries and fish culture.
Invasive species
Clarias catfish and primarily Clarias batrachus (walking catfish) have been introduced to many different areas of the world, where they are causing problems for the native wildlife. The effect of introduction of these fish varies from area to area, but as they are predatory, they often affect the local wildlife by eating other fish, birds, and amphibians. In Florida, the fish are causing problems by invading aquaculture farms and preying on the fish cultivated there. Countries where one or several Clarias species have been introduced include Indonesia, the United States, Hong Kong, China, UK, Papua New Guinea, Guam, Taiwan, Thailand, and Cuba.
^Mwita, CJ; Nkwengulila, G. (2008). "Molecular phylogeny of the clariid fishes of Lake Victoria, Tanzania, inferred from cytochrome b DNA sequences". Journal of Fish Biology. 73 (5): 1139–1148. doi:10.1111/j.1095-8649.2008.01935.x.