Dwarf pufferfish

Lore & Background

The dwarf pufferfish was first described as Tetraodon (Monotretus) travancoricus in 1941 by S.L. Hora and K.K. Nair, with the type locality given as 'Pamba River, Central Travancore'. Carinotetraodon was considered a synonym of Tetraodon until 1978, when J.C. Tyler treated it as a valid genus. The first use of 'Carinotetraodon travancoricus' was in 1999 by R. Britz and M. Kottelat when describing Carinotetraodon imitator. The genus name derives from Latin 'carina' (keel-shaped) and Greek 'tetra' (four) and 'odous' (teeth). The move to Carinotetraodon was based on osteological evidence, including vertebral modifications and reduced vertebrae, as well as small size and sexual dimorphism. A cladogram based on molecular evidence shows the genus is polyphyletic, meaning members share traits but not necessarily an immediate common ancestor.

Reader's Guide

The dwarf pufferfish is significant in fishkeeping for its bright colours, small size, and unique behaviors. It is one of the smallest pufferfish in the world, reaching a maximum total length of 3.5 cm. In the wild, it dwells at the bottom of heavily vegetated waterways and is found in large groups, unlike other pufferfish. It breeds throughout most of the year, with spawning pairs producing 1–5 eggs in 1–4 day intervals. The species is threatened by habitat loss and overharvesting for the aquarium trade, and is classified as vulnerable on the IUCN Red List. In captivity, dwarf pufferfish benefit from a varied diet including small freshwater snails, shrimps, and live foods. They are commonly associated with plants in the genus Cabomba, which have been shown to reduce mortality among captive specimens. The species is also notable for its resemblance to Carinotetraodon imitator, which was mistaken for the same species until 1999. Dwarf pufferfish can be distinguished by their darker yellow colouration and iridescent 'eye wrinkle' in males, as well as larger blotches and more body spination.

Did You Know?

• Dwarf pufferfish are one of the smallest pufferfish in the world, with a maximum total length of 3.5 cm.
• They are found in large groups in the wild, unlike other pufferfish species.
• The species produces tetrodotoxin, a highly lethal neurotoxin for which there is no antidote.