catfishes

Catfishes, or Siluriformes, are an order of ray-finned fish distinguished by their barbels, or whisker-like sensory organs, around the mouth. The group is highly diverse, with more than 3,000 described species and a wide range of body shapes and sizes. Catfishes are found worldwide, predominantly in freshwater rivers and lakes, but several families inhabit brackish or marine environments, especially in tropical regions.

Most catfishes lack true scales and have smooth or armored skin. A partial or full adipose fin is present in many species. The dorsal and often the pectoral fins bear sharp spines, which can be venomous in some lineages. Size ranges from small species only a few centimeters long to large forms such as the wels catfish and the Mekong giant catfish.

Catfishes occupy diverse ecological roles. They are mostly bottom-dwellers and feed on detritus, algae, invertebrates, or small vertebrates, using their barbels to sense food in murky water. Reproduction varies by lineage; most species lay eggs and exhibit some form of parental care, including nest guarding or, in certain groups, mouthbrooding.

Catfishes have significant human interactions. They are important in commercial and subsistence fisheries in many regions and are popular in the aquarium trade. Some species have been introduced outside their native ranges and can become invasive. Habitat loss, overfishing, and pollution threaten many catfish species, though conservation status varies widely among species.