Species of Freshwater Pufferfish
- Pufferfish Enthusiasts Worldwide
- Sep 30
- 9 min read
Updated: Oct 2
Pufferfish are best known as quirky marine oddities, famous for their ability to inflate into a ball when threatened.
The majority of species are indeed found in saltwater or brackish coastal habitats, where they have evolved to thrive in reefs, lagoons, and estuaries. However, a smaller but equally fascinating group of puffers has adapted to live exclusively in freshwater.
These species occur across Africa and Asia, inhabiting rivers, floodplains, and lakes, and they display just as much personality and uniqueness as their ocean-dwelling relatives.
Freshwater puffers are highly diverse, ranging from the tiny Carinotetraodon travancoricus (often called the pea puffer), which rarely exceeds 2.5 cm in length, to giants like the Tetraodon mbu, a fish capable of reaching more than half a metre and requiring enormous aquaria. They can be beautifully patterned, strikingly aggressive, surprisingly intelligent, and in some cases, highly specialised in their behaviour and diet.
Because of this variety, freshwater puffers hold a special place in the aquarium hobby.
They challenge conventional fishkeeping, as many species demand more complex setups, specialised diets, or careful water management than typical community fish. At the same time, they reward dedicated keepers with remarkable interactions, problem-solving behaviour, and individual personalities unmatched in most other aquarium fish.
This article explores the recognised species of freshwater pufferfish, highlighting their natural distribution, size, and characteristics. From West African river giants to tiny Southeast Asian oddballs, these fish represent one of the most captivating groups in the freshwater world.
Genus Tetraodon
The African Tetraodon species are among the largest and most famous freshwater puffers in the world. They inhabit vast river systems such as the Congo, Nile, and Niger, and they include both enormous giants and more moderately sized species. These puffers are typically bold, intelligent, and often aggressive, with powerful beaks to hunt a wide variety of prey.
They have a reputation for being demanding aquarium residents due to their size, dietary needs, and territorial behaviour, but they remain some of the most impressive freshwater fish ever kept.
Tetraodon mbu – Mbu Puffer The largest of all freshwater puffers, reaching up to 67 cm (26″). Native to the Congo River Basin, where it roams vast stretches of open water. Highly intelligent and active, but requiring aquaria in the thousands of litres.
Tetraodon lineatus – Fahaka Puffer A boldly patterned giant from the Nile, Chad, and Niger basins. Growing beyond 45 cm, it is extremely aggressive and best kept alone. Striking yellow-and-brown banding makes it a favourite among enthusiasts. Click here to read our care guide
Tetraodon miurus – Congo Puffer A sedentary ambush predator that buries itself in sand, waiting to strike at passing prey. Native to the Congo River, it shows remarkable colour variation from red to dark brown, often blending with its environment. Click here to read our care guide
Tetraodon schoutedeni – Spotted Congo Puffer A mid-sized species (up to ~15 cm) with golden spots over a green-brown body. Found in the Congo Basin and unusual among puffers for showing relatively social tendencies, sometimes tolerating conspecifics in aquaria. Click here to read our care guide
Tetraodon pustulatus – Cross River Puffer A rare species confined to the Cross River basin in Nigeria and Cameroon. Reported to reach around 40 cm in length. Sometimes known as the Redline Puffer, but rarely seen in the aquarium trade.
Tetraodon duboisi – Malebo (Stanley) Puffer Endemic to Pool Malebo on the lower Congo River. One of the smallest African Tetraodon, rarely exceeding 9 cm. Extremely uncommon in captivity. At present, there is no dedicated care guide for this species, but its husbandry requirements are understood to be virtually identical to those of T. miurus. Keepers are advised to refer to the T. miurus care guide until further material becomes available.
Genus Carinotetraodon
Carinotetraodon contains the smallest members of the freshwater puffers, many of which are favourites in the aquarium hobby, such as the Pea Puffer, due to their manageable size and bold personalities.
These puffers are native to South and Southeast Asia, where they typically inhabit slow-moving streams, rice paddies, and densely vegetated backwaters.
Sexual dimorphism is pronounced in several species, with males developing striking colour patterns or red markings, while females remain more subdued.
Carinotetraodon travancoricus – Pea Puffer / Dwarf Puffer The smallest pufferfish in the world, reaching only 2.5 cm. Endemic to India’s Western Ghats, confirmed from Kerala and into southern Karnataka, where it inhabits slow-flowing, plant-choked streams. Hugely popular in aquaria, but still demanding in terms of diet and environmental stability. Best kept in species-only setups due to its territorial nature. Click here to read our care guide
Carinotetraodon irrubesco – Red-Tailed Red-Eye Puffer
A small but vividly marked species from Sumatra and Borneo. Males develop a bright red tail and red eyes, making them one of the most attractive of the dwarf puffers. They require heavily planted aquaria with numerous hiding places to reduce aggression. Click here to read our care guide
Carinotetraodon imitator – Imitator Puffer
Closely related to the pea puffer and also native to Kerala, India. It reaches a similar size (around 2.5–3 cm) but differs in patterning, with less distinct spotting and subtler markings. Rarely encountered in the aquarium trade and often misidentified as C. travancoricus. There is no dedicated guide for this species, but its requirements are identical to those of C. travancoricus, so keepers are advised to refer to the Pea Puffer guide for correct care.
Carinotetraodon lorteti – Red-Eye Puffer
Widespread in Southeast Asia, particularly in Thailand and Cambodia. Males are easily recognised by their vivid red eyes and darker colouration, while females are more plainly marked. Known for being aggressive and best kept in pairs or singly.
Carinotetraodon borneensis – Bornean Red-Eye Puffer Found in the island’s forest streams, this species closely resembles C. lorteti but is more restricted in range. It remains small, with males showing red eyes and stronger markings than females. Rare in the aquarium trade.
Carinotetraodon salivator – Striped Red-Eye Puffer Native to Borneo and Sarawak. Distinguished by vertical striping along the body. Another small, aggressive species requiring dense planting and careful stocking.
Genus Pao
Pao is the most diverse genus of freshwater pufferfish, distributed widely across Southeast Asia.
They inhabit rivers, floodplains, swamps, and backwaters from Thailand and Laos to Cambodia, Vietnam, Malaysia, and Indonesia, occupying habitats that range from still, plant-choked channels to fast-flowing rapids.
In aquaria, Pao puffers are generally aggressive and highly predatory. Most must be kept alone, as they are extremely territorial and capable of serious damage to tankmates. Their diet centres on hard-shelled invertebrates, which are essential for tooth wear, although some individuals accept frozen or prepared foods.
The taxonomy of Pao is under active review. Molecular and morphological studies continue to reveal cryptic diversity, synonymies, and unresolved boundaries between species, and even today, specimens that appear to represent undescribed taxa are still being collected in their native ranges.
Depending on the authority, between twelve and fifteen species are recognised. As of September 2025, Eschmeyer’s Catalog of Fishes currently treats thirteen as valid, while FishBase lists slightly different combinations.
Species recognised by most authorities today
Pao abei A small, slender-bodied species from the Mekong, Chao Phraya, and Mae Klong basins. Subtle in patterning and rarely seen in aquaria.
Pao baileyi – Hairy Puffer Found in fast-flowing stretches of the Mekong in Laos and Thailand. Covered in skin filaments that give it a “hairy” or mossy look, especially when young. A territorial and unusual species that commands attention. Click here to read our care guide
Pao barbatus A species of the Mekong drainage, revalidated as distinct from P. cochinchinensis. Patterned with reticulations and bars, but rarely encountered in the trade.
Pao bergii Native to the Kapuas River system of Borneo. Little known outside scientific records, and very seldom imported.
Pao cochinchinensis (with P. cambodgiensis often treated as a synonym) Distributed across the Mekong Basin in Cambodia and Vietnam. A subtly patterned, mid-sized species occasionally appearing in the hobby.
Pao fangi (with P. brevirostris often treated as a synonym) Occurs in the Mekong and Chao Phraya drainages. Small to mid-sized, with a short snout and mottled markings. Rare in aquaria.
Pao hilgendorfii Endemic to the Mahakam River in East Borneo. A rounded-bodied species, often confused with P. suvattii, though geographically distinct. Almost never seen in the trade.
Pao leiurus One of the more frequently imported species. Widely distributed from Thailand to Indonesia, including Sumatra and Java. Unusual within the genus for tolerating both freshwater and brackish environments. Grows to around 16 cm.
Pao ocellaris Native to the Malay Peninsula. Notable for its ocelli, or eye-like spots, on the body. Rarely imported but distinctive in appearance.
Pao palembangensis – Dragon / Humpback Puffer Distributed through southern Thailand, Peninsular Malaysia, Sumatra, and Borneo. Laterally compressed with a humped back, camouflaging among leaf litter as a sit-and-wait predator. Sometimes available in the aquarium trade, and known for its unusual body shape. Click here to read our care guide
Pao suvattii – Arrowhead / Pignose Puffer Native to the Mekong Basin of Laos, Thailand, and Cambodia. A classic ambush predator, it buries in sand until prey passes within striking distance. Highly aggressive and always best kept alone. Click here to read our care guide
Pao turgidus Found throughout the Mekong system, extending into southern China. Grows to around 18 cm. Known to produce saxitoxins rather than tetrodotoxin. Rare in captivity. Click here to read our care guide
Under active review or debated
Pao cambodgiensis Range. Mekong, especially Cambodia and adjoining regions.Notes. Often listed in broader 15-name treatments.Synonymy note. Frequently treated as a synonym of P. cochinchinensis.
Pao brevirostris Range. Reported from marsh and swamp habitats in parts of the Mekong.Notes. Still appears in some summary lists. Synonymy note. Frequently treated as a synonym of P. fangi.
Pao palustris Range. Described from Thai Mekong marshes in 2013.Notes. Very little known, not present in the trade. Validity has been questioned.Synonymy note. Treated as valid by some authorities, but in other sources it is linked indirectly to the brevirostris to fangi synonym chain.
Genus Leiodon
Leiodon is a tiny genus with a big personality. It holds just two species that sit at opposite ends of the habitat map.
Cutcutia is the freshwater representative, ranging across South and Southeast Asia in rivers, floodplains, canals and ponds. Its cousin, L. dapsilis, prefers the coast of northern Australia, turning up in mangroves, estuaries and shallow marine shallows.
Both are curious, bottom-oriented puffers with serious beaks for crunching snails and other invertebrates, and both seem to spend half their day people-watching from the glass.
Freshwater species
Leiodon cutcutia - Cutcutia / Ocellated puffer The river-dweller of the pair. Found right across South and Southeast Asia in slow rivers, floodplains and canals. Tops out at around 12–15 cm. Bright, nosy and very food-motivated. Give it space, steady water, lots of cover, and regular crunchy foods to keep the beak honest. Best kept as a single fish. Your Cutcutia guide covers the care in detail. Click here to read our care guide
Genus Sphoeroides
Most Sphoeroides cruise seagrass, mangroves and tidal creeks, perfectly at home in shifting brackish and nearshore marine waters, but this mostly coastal genus now includes two freshwater members from South America.
Taxonomists have shuffled the deck in recent years, and many sources place the Amazon basin “Colomesus” puffers inside Sphoeroides.
Freshwater species
Sphoeroides asellus (often listed as Colomesus asellus) The famous Amazon puffer. A fast, social river fish that roams long reaches and flooded forests. Big personality in a compact body, and a beak that loves crunchy invertebrates. Click here to read our care guide
Sphoeroides tocantinensis (often listed as Colomesus tocantinensis) Endemic to the Tocantins–Araguaia system. Another true freshwater river puffer that looks and behaves much like S. asellus. You will often see it mixed under the “Amazon puffer” banner, but it is its own species and just as lively.
Genus Auriglobus
These are the small golden troublemakers from Southeast Asia. Auriglobus are true freshwater puffers that stick to rivers and streams, often with a bit of push to the current. They look a lot like their big coastal cousin Chonerhinos, only leaner, smaller and far more tied to fresh water. Think green-to-gold backs, pale bellies and quick, darting movement.
These five species were long lumped with Chonerhinos until Kottelat’s work clarified the split. Today Chonerhinos is left with a single brackish–coastal species, while Auriglobus covers the small river puffers listed below.
Auriglobus modestus - (Golden or Bronze puffer) The name most keepers know. A true river fish from medium to large channels, lively and nippy, with a taste for crunchy invertebrates and the odd fin tip if it gets the chance. Usually tops out around 10–11 cm SL.
Auriglobus nefastus - (Greenbottle pufferfish) Built for current. Found from the Mekong down into Indonesia, often in fast water and flooded forests in the wet season. Notorious scale and fin nibbler. Up to about 13 cm SL.
Auriglobus amabilis A smaller Indonesian species that feeds heavily on aquatic insect larvae. Stays compact at around 7 cm SL.
Auriglobus silus Malaysia and Indonesia, riverine and strictly freshwater. Stocky little puffer that reaches roughly 8 cm SL.
Auriglobus remotus Northeastern Borneo, fully freshwater and one of the smallest in the group at about 6 cm SL. Rarely seen in the hobby.
Last reviewed: 2 October 2025.
Comments