Suckermouth Armoured Catfishes

Ancistrus claro, the gold marble bristlenose catfish (LDA 008), is a suckermouth catfish from the rios Claro and Coxipó in Mato Grosso, Brazil. It inhabits flowing streams over boulders and bedrock. Sometimes confused with unidentified fishes such as A. sp. 'L352', it has long maxillary barbels and small spots on the head, with vermiform lines on the body in males and spots all over in females. A peaceful cave-spawner, it has been bred in aquaria on numerous occasions.

Rineloricaria parva is a whiptail catfish from Brazil, Paraguay and Argentina, found among leaf litter over sandy substrates. Commonly sold as a 'whiptail catfish', it is difficult to identify: the true R. parva has dark bands across the top of the body only and filaments on the top and bottom of the caudal fin. Some fish seen for sale may be hybrids with other species.

Rineloricaria lanceolata is a whiptail catfish from Peru and Brazil, usually found among leaf litter over sandy substrates. One of the most common species sold as 'whiptail catfish', it breeds quite easily in suitable conditions, although the fry can be tricky to raise. Very peaceful, it is easily out-competed for food by vigorous or aggressive tankmates.

L255, the spotted medusa plec, is a wide-headed, flattened Ancistrus known only from the middle rio Xingu basin in Pará state, Brazil. It lives among rocks in shallow, fast-flowing water, needs well-oxygenated water with plenty of movement and a protein-rich diet, and is often in poor condition after import. It resembles A. ranunculus, but keeps its light body markings throughout life, whereas those of A. ranunculus fade as the fish matures.

The common bristlenose catfish, Ancistrus sp. '3', is the loricariid sold everywhere as the 'bristlenose', of unknown origin and bred commercially. It was once thought close to the Argentinian A. cirrhosus, but genetic data suggests otherwise, and some consider it a hybrid. Adult males carry fleshy tentacles on the head, and the species spawns in caves with the male guarding the brood.

The twig catfish, Farlowella vittata, is a stick-like loricariid from the Orinoco river basin in Colombia and Venezuela. This is the most common Farlowella in hobbyists' tanks, although much of the literature refers to it as F. acus, which has a shorter, less slender rostrum. It is super sensitive to poor water quality and should only go into an established aquarium with a good biofilm, algae or dried leaves.

Lasiancistrus tentaculatus (L092, L194) is a wood-eating suckermouth catfish from Colombia and Venezuela. The only primarily wood-eating Lasiancistrus, it will not do well without wood as a food source, and lives among driftwood snags in rivers. Mature males develop a few Ancistrus-like tentacles around the mouth, the only species in the genus to do so. Sunken eyes and a belly that is not rounded are classic signs of emaciation in newly imported fish.

The galaxy plec, Leporacanthicus galaxias (L029), is a suckermouth catfish from the Amazon, Tocantins and other river basins in Brazil. Also sold as the vampire or tusken plec, it lives in rapids and other fast-flowing waters. Four similar undescribed variants, L007, L240, L241 and L294, are known as L. cf. galaxias and are best referred to by their L numbers.

L038 is an unidentified Peckoltia, a suckermouth catfish collected near Mocajuba on the lower rio Tocantins in Pará state, Brazil. It is relatively peaceful but territorial with conspecifics and similarly-shaped species, and spawns in caves with the male responsible for brood care.

The common whiptail catfish, Rineloricaria eigenmanni, is a peaceful loricariid from Colombia and Venezuela, found among leaf litter over sand. One of the most common species sold as 'whiptail catfish', it breeds quite easily and suits a newcomer to catfish breeding. It is often mixed up with other species: in R. eigenmanni the black bars on the caudal peduncle continue right around the fish, and the fins are barred.

Rineloricaria fallax is a whiptail catfish from the upper Rupununi and Branco river basins in Guyana and Brazil. One of the most common species sold as 'whiptail catfish', it breeds quite easily and suits a newcomer to catfish breeding. It lives among leaf litter over sand in shallow, flowing water, and is very peaceful but easily out-competed for food.

The red lizard catfish (Rineloricaria sp., L010a) is a red whiptail catfish of unclear origin, and all fish seen for sale appear to be tank-bred. Some believe it derives from a wild fish, possibly from Paraguay, while others suggest a selectively-bred form of R. lanceolata or a hybrid with it. Very peaceful, it breeds quite easily in suitable conditions.

The horned bristlenose pleco, Ancistrus triradiatus, is a small suckermouth catfish from Colombia and Venezuela, found among rocks in flowing streams. It is often confused with the common bristlenose, Ancistrus sp. (3), and other congeners, and some are so similar that a definite identification needs the collection locality. Imported fish are almost always wild-caught. Mainly vegetarian and peaceful, it is easy to breed once mature.

Hypoptopoma incognitum is a loricariid catfish described from the Río Itenez, northeastern Bolivia, and the most widespread member of its genus. It has been recorded through much of the central and lower Amazon basin, the rio Tocantins, and some minor rivers draining straight into the Atlantic in northeastern Brazil.

L147 is an undescribed Ancistomus species, a suckermouth catfish from tributaries of the middle Río Orinoco in Venezuela and the lower Río Meta in Colombia. Some reports suggest it occurs further up the Meta system, around Villavicencio, some 600 km upriver. It spawns in caves with the male responsible for brood care, and has been bred regularly in aquaria.

The big spot peckoltia (L163) is an undescribed suckermouth catfish collected from the Rio Pará in the Brazilian Amazon. Trade fish are often confused with the very similar L013, and the two are only easily told apart as they mature: L163 keeps its spotted pattern while L013 tends to become duller. It is placed in the genus Ancistomus. Newly imported fish should have a rounded belly and eyes that are not sunken.

Ancistrus dolichopterus, the starlight ancistrus (L183), is a bristlenose catfish most likely endemic to the middle and lower rio Negro, Brazil. It inhabits blackwater streams. The name has been used for the common bristlenose and other similar species, while this fish has been called A. hoplogenys, and much of the literature confuses them. It differs from all congeners in having 9 soft dorsal-fin rays, and is territorial with conspecifics and similarly-shaped species.

Ancistrus ranunculus, the medusa pleco (L034), is a wide-headed, flattened suckermouth catfish from the rio Xingu and rio Tocantins basins in Brazil. It lives among rocks in shallow, fast-flowing water, needs well-oxygenated water with plenty of movement and a protein-rich diet, and is often in poor condition after import. Juveniles carry light spots like the similarly shaped L255, but in A. ranunculus these fade as the fish matures.

Known as L239 before description, Baryancistrus beggini is a small loricariid from the Orinoco and lower río Guaviare in Venezuela and Colombia. Its body and fins are uniformly black to brownish with a turquoise to bluish sheen. Placement in Baryancistrus is tentative. Territorial with conspecifics but somewhat delicate, it is not recommended for the general community aquarium.

The mango pleco, Baryancistrus chrysolomus, traded as L047, is a loricariid endemic to the rio Xingu basin in Pará state, Brazil. A broad, usually yellowish band along the edges of the dorsal and caudal fins throughout life separates it from B. xanthellus, whose bands shrink to tips in adults. It grows to around 220 mm SL, and males in particular become highly intolerant of conspecifics as they age.

The green phantom pleco, Baryancistrus demantoides, is a suckermouth catfish known only from where the río Ventuari meets the Orinoco in Venezuela. It closely resembles Hemiancistrus subviridis, which lives alongside it, and both have been marketed as L200. B. demantoides is the less common and more expensive of the two, sometimes sold as 'L200 high-fin' or 'L200a' for its longer dorsal-fin spine. Males become increasingly intolerant of conspecifics as they age.

The big white spot pleco, Baryancistrus sp. L142, is an undescribed suckermouth catfish from the rio Tapajós in Pará state, Brazil. It appears restricted to a short stretch of the river between Itaituba and Pimenta, in shallow, fast-flowing, warm water. The species is also traded as 'snowball pleco', a name first applied to Hypancistrus inspector and now used for several similar white- or yellow-spotted fishes. Males become highly intolerant of conspecifics as they age.

The gold nugget pleco, Baryancistrus xanthellus, is a suckermouth catfish endemic to the rio Xingu basin in Pará state, Brazil. It lives in whitewater rapids in the Volta Grande do rio Xingu, between Belo Monte falls and the mouth of the rio Iriri. Before its description it was traded as L018, L085, L177 and LDA060, and L081 is the same fish. Males become highly intolerant of conspecifics as they age.

The striped bulldog pleco, Chaetostoma formosae, is a suckermouth catfish from piedmont streams of the upper Meta and Guaviare systems in Colombia. The commonest member of the genus in the hobby, it is still misidentified as C. thompsoni and sold under several names and L-numbers. An obligate inhabitant of fast-flowing headwater streams, it needs clean, well-oxygenated water with strong flow and does best in a dedicated species set-up.

The butterfly plec, Dekeyseria picta (L168), is a flattened loricariid catfish from the Rio Negro in Brazil. The Rio Orinoco fish traded as L052 is now included in the same species. Also called the chameleon plec, it changes colour to match the substrate and other surfaces and has a distinctive night-time colouration. It needs well-oxygenated water with plenty of movement.

L106, Hemiancistrus guahiborum, is a suckermouth catfish known only from the Rio Orinoco drainage in Venezuela. Also known as the spotted orange seam plec, it lives amongst rocks in flowing water and needs well-oxygenated water with some current. Described in 2005, it may be the same species as the undescribed L122, although the flatter profile of L122 suggests the two are distinct.

The blue phantom plec (L128) is a suckermouth catfish known only from the northern Rio Orinoco drainage in Venezuela. Its identity is unresolved. It closely resembles Hemiancistrus subviridis, the green phantom plec (L200), and the colour of the two grades from one into the other along the same river system, suggesting colour forms of one species, but this awaits scientific confirmation. Newly imported fish can be delicate, and emaciated fish with sunken eyes do not often survive for long.

The Pinocchio whiptail catfish, Hemiodontichthys acipenserinus, is a loricariid from Guyana, French Guiana, Peru, Bolivia and Brazil. Also known as the knob nosed whiptail, it is hard to confuse with any other Loricariid thanks to its diamond shape seen from above and the enlarged tip of its rostrum. Imports often arrive weak from oxygen deprivation and early losses are high, but once acclimatised it is quite easy to keep over the soft sand in which it partially buries itself.

The snowball pleco (L102), Hypancistrus inspector, is a suckermouth catfish from the upper rio Negro in Brazil and the Casiquiare in Venezuela. Brown to black with large whitish to yellow spots, it is most similar to H. contradens. It is normally collected from rocky rapids, is a cave-spawner with male brood care, and should not be kept with other Hypancistrus in order to prevent hybridisation.

The king tiger plec, Hypancistrus seideli, is a suckermouth catfish from the lower rio Xingu in Pará state, northern Brazil. Described by Sousa et al. in 2025, it is traded as L066 and L333 and also as 'network pleco' and 'scribbled pleco'. Its colour pattern is highly variable and it is regularly confused with L400. It inhabits turbulent whitewater rapids, much of which is likely to be severely degraded by the Belo Monte dam.

L004, the angelicus pleco, is an undescribed Hypancistrus from tributaries of the lower Amazon near its mouth in Pará state, northern Brazil. It is sometimes traded under the false name 'Peckoltia angelicus', and the codes L004, L005, L028 and L073 represent distinct populations from the Tocantins, Guamá and Pará rivers. Peaceful but territorial towards its own kind, it has been bred in aquaria many times.

L260, the queen arabesque pleco, is an undescribed Hypancistrus known only from the lower rio Tapajós in Pará state, northern Brazil. Among the most popular loricariids in the hobby, it is available on a regular basis. The larger L411 from the rio Jarí looks similar, but in L260 the white vermiculations are significantly finer. The area where it is collected would be largely destroyed should a planned hydroelectric project go ahead.

L136 is an undescribed Hypancistrus from the rio Negro basin in Amazonas state, Brazil, collected in particular from the rio Demini. Highly variable in colour pattern, it has been assigned a series of L-numbers as a result. A peaceful cave-spawner with male brood care, it has been bred regularly in aquaria, but should not be kept with other Hypancistrus in order to prevent hybridisation.

The zebra plec, Hypancistrus zebra (L046), is a small loricariid catfish from the Rio Xingú basin in Brazil, named for its zebra pattern. Brazil banned its export in 2004 and captive-bred fish are expensive. Shy and easily outcompeted for food, it needs warm water of 26 to 30 °C, high oxygen levels and pristine conditions, and does not suit the general community tank.

The spotted cochliodon (L050), Hypostomus cf. cochliodon, is an undescribed suckermouth catfish of the Hypostomus cochliodon complex. Like other members of the group it develops a hump-backed profile and spoon-shaped teeth, and eats wood. Its exact distribution is unknown. It grows to around 230 mm SL and is non-territorial enough to keep in a group or with other peaceful loricariids.

LDA10, Hypostomus mutucae, is a small suckermouth catfish from Mato Grosso, Brazil, with its type specimen collected in the Rio Mutuca. It grows to around 75 mm and is peaceful, and it inhabits flowing, highly oxygenated water over sand scattered with rocks. It is often confused with LDA09 but has smaller spots on the head, where LDA09 has larger spots of uniform size all over.

Hypostomus plecostomoides (LDA42, LDA38) is a wood-eating suckermouth catfish from the Rio Orinoco drainage in Colombia and Venezuela. A member of the Hypostomus cochliodon complex, it has a hump-backed profile and spoon-shaped teeth. It is very difficult to tell from H. hondae, H. pagei and H. taphorni, and collection locality is often the best guide.

L077, the rusty, bruno or violet plec, is an undescribed wood-eating suckermouth catfish of the Hypostomus cochliodon complex from the rio Parnaíba basin in north-eastern Brazil. It grows to around 300 mm SL.

L229 is an undescribed wood-eating suckermouth catfish of the Hypostomus cochliodon complex from the Río Ucayali, Peru. Like others in the group it develops a hump-backed profile and spoon-shaped teeth. It lives around driftwood in flowing parts of rivers and streams, and grows to around 200 mm SL.

L231 is an unidentified Hypostomus, a large suckermouth catfish said to be exported from the upper Amazon region of Peru. Precise details of its origin are lacking. It grows to 250 to 300 mm SL and needs an aquarium of at least 180 by 60 cm, and it is unclear whether it is the same species as the similarly nameless L266.

Isorineloricaria acuarius is a suckermouth catfish from the Apure and middle Orinoco drainages in the Venezuelan Llanos, where it lives on sandy runs in whitewater rivers. Traded as L093 and L195, the blue fin thresher pleco, it was sold as Hypostomus villarsi until it was described in 2016. I. villarsi is a different fish from the Lake Maracaibo basin, with a sharp ridge on each side of the head where I. acuarius has a rounded one.

The sturgeon catfish, Lamontichthys filamentosus, is a loricariid from the central and western Amazon in Brazil, Peru, Ecuador and Bolivia. Above 60 mm SL the pectoral-fin spine extends into a filament that can be over four times the length of the first branched ray, and the dorsal-fin spine carries a similar extension. Relatively common in the hobby but not easy to maintain, it needs clean, well-oxygenated water and a mature aquarium with plenty of algae-covered surfaces.

Lamontichthys llanero is a suckermouth catfish from the Orinoco basin in Venezuela. It lives among rocky substrates and driftwood snags in shallow, flowing water, and needs well-oxygenated water with plenty of movement. Unaggressive and peaceful with conspecifics, it is rarely seen in the hobby.

The golden vampire plec, Leporacanthicus heterodon, is a suckermouth catfish from the Rio Xingu basin in Brazil. It lives in rapids and other fast-flowing waters. The 'vampire' name refers to the two large teeth in the upper jaw shared by the genus, probably used to grip prey such as snails.

The sultan plec, Leporacanthicus joselimai (L264), is a suckermouth catfish from the Rio Tapajós in Brazil. It lives in rapids and other fast-flowing waters among rocks and driftwood snags. Young fish have white fin tips that fade with growth and often disappear completely. Territorial with conspecifics, particularly males, it has been bred in the hobby as a cave spawner.

The three beacon plec, Leporacanthicus triactis (L091), is a suckermouth catfish from the upper Orinoco basin in Colombia and Venezuela. Several colour forms are available with varying amounts of orange in the fins, some sold as 'dragon fin' or 'tiger fin', and the colour is retained as the fish matures. It lives in rapids and is territorial with conspecifics, particularly males.

The zebra oto, Otocinclus cocama, is a miniature loricariid from Peru, thought to occur throughout the lower Ucayali and Marañon. Vertically elongated blotches from the dorsal midline to the belly distinguish it from all congeners, and it has a complete lateral line. It can be delicate when first imported and benefits from quarantine in a tank with a good biofilm to graze.

Otocinclus macrospilus, one of the commoner otos in the hobby, is a small loricariid endemic to parts of the Upper Amazon in Peru. It is frequently mislabelled as O. affinis or O. vittatus, and a large round black blotch at the base of the caudal fin separates it from O. vestitus. Imported fish can be delicate, usually through starvation in transit, and do best added to mature, planted tanks.

L403 is an undescribed wood-eating suckermouth catfish in the genus Panaqolus, known only from the rio Anapu in Pará state, Brazil. The species is xylophagous, feeding primarily on wood, so driftwood must be provided. It should be given a mainly vegetarian diet, with meaty foods kept to a minimum. It has been bred in aquaria.

The brown dot peckoltia (Peckoltia oligospila), also known as L006, is a suckermouth catfish from the rios Tocantins and Capim in Brazil. Only faint spots and saddles mark its body, a pattern it shares among congeners with P. bachi and some specimens of P. furcata alone. Relatively peaceful but territorial with conspecifics, it is a cave-spawner and does best in a tank designed to simulate a flowing stream.

L288 is a Peckoltia species, a suckermouth catfish from the rios Curuá Una and Uruará in Pará state, Brazil. The Curuá Una joins the main lower Amazon channel downstream of Santarém and carries a large hydroelectric power plant. The species spawns in caves with the male responsible for brood care.

L076 is a Peckoltia species, a suckermouth catfish apparently collected from the rio do Pará near Portel in Pará state, northern Brazil. L076 and L099 appear to be the same species, the former showing a darker colour pattern by day, though both look similar at night. It spawns in caves and the male is responsible for brood care.

Peckoltia wernekei, also known as L243 and LDA086, is a suckermouth catfish known only from parts of the upper Río Orinoco drainage in Amazonas state, southern Venezuela. Armbruster and Lujan described it in 2016 from the Ventuari drainage. It is sometimes confused with Peckoltia lineola, alongside which it is often exported for the aquarium trade.

The bola pleco, Peckoltichthys bachi, is a loricariid catfish from the upper Amazon region in Brazil, Colombia, Ecuador and Peru. It has been assigned several L-numbers, including L146 from Colombia and L232 from the Río Putumayo/Içá, and has been exported under other generic names including Hemiancistrus and Sophiancistrus. Its mottled colour pattern separates it from most Peckoltia species, and it lives among submerged grasses and branches in flowing water along the margins of medium to large rivers.

L114, Pseudacanthicus cf. leopardus, is a loricariid collected mostly in the rio Negro basin in Brazil, particularly the rio Demini. P. leopardus was described from the Rupununi River in Guyana, so the identity of this fish remains unconfirmed. Traded as the Demini leopard cactus pleco or simply 'leopard cactus pleco', it grows to 250 mm and needs an aquarium of at least 180 x 60 cm set up to simulate a flowing river.

The giant whiptail catfish, Pseudohemiodon laticeps, is a loricariid from the rios Uruguay, Paraná and Paraguay in Brazil, Paraguay and Argentina. Growing to 300 mm, it stays buried in soft substrate by day and emerges to feed at night, so a sandy substrate and very clean, stable water matter most. The male is a paternal 'lip brooder', carrying the eggs on his labial barbels for 12-14 days, and the species has been bred in aquaria.

Rineloricaria morrowi is a loricariid catfish from the Ucayali River basin, Peru, found among leaf litter over sandy substrates. It is seen less often than some others in the genus. Briefly placed in the resurrected genus Hemiloricaria in 2002, it was returned to Rineloricaria within a year, but the old name is still used quite often.

The red fin thresher plec, Aphanotorulus emarginatus, is a suckermouth catfish from the Amazon region of Brazil, Ecuador, Peru and Bolivia. Many geographical variants exist, four of them assigned L-numbers (L011, L035, L108 and L116), and all share the elongated caudal fin that gives the fish its common name. Often sold at 3-4" as Hypostomus cf. emarginata, it grows to around 40 cm and needs a spacious tank with well-oxygenated, flowing water.

The spotted bulldog plec, Chaetostoma sp. 'L187a', is a rubbernose plec from fast-flowing mountain streams in Colombia. One of the more commonly seen Chaetostoma, its true identity is uncertain and it is sometimes misidentified in shops. It needs clear, cool, well-oxygenated water with plenty of movement, and it is territorial with its own kind unless each fish has a rock of its own.

The giant white spot plec, Hypostomus regani, is a large suckermouth catfish from Brazil, Paraguay, Uruguay and Argentina. It is very hardy and grows to around 400 mm SL. Peaceful with most tankmates, it is territorial with similarly-sized bottom dwellers, especially its own kind, so a very large tank is needed to keep other large catfish with it.

The marbled whiptail, Loricaria simillima, is a whiptail catfish recorded from Venezuela, Ecuador, Peru, Brazil, Paraguay and Argentina. There is a great deal of uncertainty about its identity, and several species or subspecies are probably involved, with darker fish collected from blackwaters and lighter ones from whitewater habitats. The fish in the trade is quite possibly not L. simillima at all. It has been bred in aquaria and shows parental care.

The green whiptail, Acestridium dichromum, is a small loricariid catfish from the upper rio Negro in Brazil and the upper Orinoco in Venezuela. It is known only from those two basins and the drainages between them, including the Casiquiare Canal.

The polka dot lyre tail pleco, Acanthicus adonis, is a very large loricariid catfish from the rio Tocantins in Brazil. Thought to range across much of the Amazon basin, it is traded as spotted juveniles in quite large numbers despite its patent unsuitability for aquaria. It reaches 600 mm or more, loses its spotted patterning as it matures and becomes increasingly belligerent with age, so it can only be recommended to owners of the largest private aquaria or tropical ponds.

The lyre tail pleco, Acanthicus hystrix, is a very large loricariid catfish from the Amazon region of Brazil and Peru. A handful of records come from the Orinoco in Venezuela. Juveniles are traded in quite large numbers, but it can reach at least 1000 mm in nature and 500 to 600 mm in captivity, and becomes increasingly belligerent with age. Young fish are easily told from A. adonis by lacking its white to yellowish body spots.

L113, Megalancistrus parananus, is a large suckermouth catfish from the rios Paraná, Paraguay and Uruguay in Brazil, Paraguay, Uruguay and Argentina. It was formerly thought to include L234, but only L113 appears native to these drainages, while L234 comes from the rio São Francisco. The largest recorded specimen measured 588 mm, and it can behave very aggressively in confined surroundings.

L234, the dragon hi fin pleco, is a large Megalancistrus catfish known only from the rio São Francisco system in eastern Brazil. The L-number was previously applied to Megalancistrus parananus, but that species is native to the Paraná, Paraguay and Uruguay drainages, so L234 appears to be an unidentified species. It grows to 500 to 600 mm and can behave very aggressively in confined surroundings.