Kryptopterus Bicirrhis

Kryptopterus bicirrhis is an Asian catfish species belonging to the genus Kryptopterus. Although historically referred to as the “glass catfish”, this name is now more accurately associated with its smaller relative Kryptopterus vitreolus. The true K. bicirrhis is considerably larger, more opaque, and far less common in the aquarium trade. In regions of western Borneo where K. bicirrhis and Kryptopterus minor occur together, both are collectively called lais tipis in Malay, although K. minor is locally distinguished as lais limpok. In Cambodia the species is known as trey kes prak and is used in the production of the fermented fish paste prahok.

Description

Unlike the translucent K. vitreolus, the genuine K. bicirrhis reaches a far greater size, with adults attaining a substantial standard length. Its body is largely opaque and greyish, displaying only limited translucency near the head. Under direct light, the fish shows a distinct iridescence, and upon death its colour shifts to a milky white. The species possesses two exceptionally long barbels, extending to a length comparable to the anterior part of the body before the anal fin, and used for locating food in turbid water. Additional distinguishing features include a very small triangular dorsal fin and pectoral fins that exceed the length of the head.

Distribution and Habitat

Kryptopterus bicirrhis is distributed across parts of Southeast Asia, including Borneo, Sumatra, the Malay Peninsula, and the major drainage systems of the Chao Phraya and Mekong Rivers. It inhabits freshwater environments, particularly large rivers characterised by turbid, fast-flowing water. The species shows a preference for peaty, cooler waters relative to other tropical fishes. Ecologically, K. bicirrhis is a diurnal predator feeding primarily on aquatic insects of the suborder Nepomorpha, with occasional predation on smaller fish.

Magnetic Field Sensitivity

Research indicates that K. bicirrhis displays pronounced sensitivity to magnetic stimuli, an unusual feature for a non-migratory fish. It possesses electroreceptive organs and exhibits a consistent behavioural response by swimming away from magnetic fields exceeding approximately 20 microtesla. This reaction has been linked to the species’ electromagnetic perceptive gene (EPG), which modulates cellular calcium levels in response to electromagnetic field strength.
The study of this sensory mechanism has potential biomedical implications. Understanding the molecular basis of the EPG response may provide insight into non-invasive methods for influencing cell activity, with possible future relevance for medical interventions such as neuromodulation and minimally invasive brain procedures.