[Ebook] Encyclopedia of Aquarium & Pond Fish – Directory of Freshwater Fish – Catfish

Directory of Freshwater Fish

Catfish

Catfish represent one of the largest groups of aquarium fish and also one of the most diverse in terms of appearance and lifestyle. There are more than 2,000 species in approximately 30 families. Some of these fish are sedentary and suitable for a community tank, while others are active predators that grow to a large size. Identification is not always easy, partly because members of the same species often show differences in patterning and partly because new species are constantly being discovered. The complex and expanding nature of one catfish family, the Loricariids, has led to the development of a classification system based on “L” numbers.

Midnight Catfish (Auchenipterichthys thoracatus)

• ORIGINS: South America, in the upper reaches of the Amazon and its southern tributaries in Peru.
• SIZE: 4 1⁄2 in (11 cm).
• DIET: Flake food, tablets, and small live foods.
• WATER: Temperature 68–75°F (20–24°C); hard (100–150 mg/l) and neutral (pH 7.0).
• TEMPERAMENT: Social.

The patterning of light spots on a dark background resembles stars in the midnight sky. As their name suggests, these catfish are nocturnal in their habits. They like to hide themselves away in holes in bogwood, anchoring themselves in place using the rays of their dorsal and pelvic fins, which are more prominent in males. Midnight Catfish will come up to the surface to feed and can be housed with nonaggressive companions of similar size.

Glass Catfish (Kryptopterus bicirrhis)

• ORIGINS: Southern Asia, from eastern India, Thailand, and Malaysia to Java, Sumatra, and Borneo.
• SIZE: 4 in (10 cm).
• DIET: Flake and freeze-dried foods, and small live foods.
• WATER: Temperature 68–79°F (20–26°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Placid.

The long body of this catfish is almost completely transparent, allowing it to assume the color of its surroundings. The only color on the fish itself is a small reddish-violet patch behind the gills. The barbels are long, as is the anal fin, which runs virtually the length of the underparts. In contrast, there is just a hint of a dorsal fin, with the pelvic fins also being rudimentary. These active catfish naturally inhabit fast-flowing streams.

Chocolate Frogmouth (Chaca bankanensis)

• ORIGINS: Southeast Asia, occurring in parts of Thailand and Malaysia, extending to Indonesia.
• SIZE: 8 in (20 cm).
• DIET: Prefers live foods, but will take tablets.
• WATER: Temperature 72–75°F (22–24°C); soft to hard (50–200 mg/l) and acidic to alkaline (pH 6.0–8.0).
• TEMPERAMENT: Predatory.

The Chocolate Frogmouth is distinguished from the Squarehead Frogmouth (C. chaca) by its richer shade of brown, but both species share similar habits. Chocolate Frogmouths hide under or behind rockwork during the day, becoming active and feeding at night. They are likely to hunt down smaller fish, so it is unwise to house them with such companions. A third species, C. burmensis, was discovered in 1988, but is little documented.

PUTTING OUT FEELERS

The different shapes and sizes of the sensory barbels surrounding the mouths of catfish provide an insight into their differing lifestyles. Often likened to feelers, barbels give catfish additional sensory information about their environment. Active predatory catfish hunt by sweeping long barbels from side to side as they swim, which helps them to detect and home in on potential prey. The longest barbels are seen in nocturnal species, or species that hunt in turbid waters where visibility is restricted. In contrast, more sedentary or vegetarian catfish have very much shorter barbels, which act as a sensory supplement to the eyes.

Banjo Catfish (Bunocephalus coracoideus)

• ORIGINS: South America, occurring in the Amazon basin, extending to the vicinity of La Plata.
• SIZE: 6 in (15 cm).
• DIET: Pellets, tablets, and sinking live food.
• WATER: Temperature 70–79°F (21–26°C); soft to hard (50–200 mg/l) and acidic to alkaline (pH 6.0–7.8).
• TEMPERAMENT: Placid and sedentary

This catfish rarely strays far from the substrate and will often try to conceal itself by burrowing in the gravel in the base of the aquarium, just as it would on riverbeds in the wild. The inclusion of shriveled oak leaves that have been previously soaked will provide extra camouflage. Pairs of these fish can breed in aquaria. The female lays up to 5,000 eggs in a pit; the male guards the eggs until they hatch.

African Glass Catfish (Pareutropius debauwi)

• ORIGINS: West Africa, occurring in the Congo and also in Gabon.
• SIZE: 3 in (7.5 cm).
• DIET: Small live foods, fresh or freeze-dried, plus flake.
• WATER: Temperature 72–79°F (22–26°C); soft to hard (50–150 mg/l) and acidic to near neutral (pH 6.5–7.2).
• TEMPERAMENT: Very placid and social.

These fish should be kept in small groups to ensure the presence of at least one pair, because it is difficult to distinguish the sexes until females swell with eggs. Ideally, two males should be housed in the breeding tank with a single female. Typically, she will lay up to 100 white eggs in the morning, after which the fish should be returned to the main aquarium. The catfish fry will hatch within three days, and are easy to rear on brine shrimp. Adults will take insect larvae very readily, especially bloodworm.

Black-Fin Shark Catfish (Ariopsis seemanni)

• ORIGINS: Occurs in rivers and estuaries on the Pacific coast, from North America to Colombia and Peru.
• SIZE: 13 in (33 cm).
• DIET: Thawed and fresh live foods, plus prepared foods.
• WATER: Temperature 72–82°F (22–28°C); soft to hard (50–300 mg/l) and neutral (pH 7.0).
• TEMPERAMENT: Not to be trusted with smaller tankmates.

The combination of the streamlined body shape and the large dorsal fin explains why this species is known as the Black-Fin Shark Catfish. The fins on the underside of the body are edged with white. Although primarily a freshwater species, the Black-Fin Shark sometimes enters brackish waters in river estuaries. In an aquarium setting, especially at first, the addition of a small quantity of sea salt (about a level teaspoon per gallon/ 4.5 liters) to the water is recommended. As the fish grow older, their characteristic coloring fades. Plenty of open space for swimming, plus a strong filter current, are essential features of their aquarium. These catfish are mouth-brooders, with the male carrying out this task.

Whiptail Catfish (Farlowella acus)

• ORIGINS: South America, occurring in southern tributaries of the Amazon, in the vicinity of La Plata.
• SIZE: 6 in (15 cm).
• DIET: Mainly vegetarian, including vegetable flake.
• WATER: Temperature 75–79°F (24–26°C); soft (50–100 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Very inactive.

The slender, brown body of this catfish makes it easy to confuse with a twig. Mature males can be recognized by bristles on their snouts. About a day before spawning occurs, the female develops an egg-laying tube called an ovipositor. She lays a clutch of up to 60 adhesive eggs, typically on rocks. The eggs are guarded, usually by the male, until the young emerge.

Chocolate Doradid (Platydoras costatus)

• ORIGINS: South America, ranging from Peru eastward through the Amazonas region of Brazil.
• SIZE: 8 1⁄2 in (22 cm).
• DIET: Catfish pellets, vegetable matter, and live foods.
• WATER: Temperature 75–86°F (24–30°C); soft (50–100 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Territorial toward its own kind.

The coloration of this species consists of distinct brownish-black and whitish-cream stripes. The “costatus” part of the scientific name refers to the riblike projections along the sides of the body. These projections will become stuck in the material of a net, so Chocolate Doradids need to be caught with great care. This species occupies the lower levels in an aquarium and will burrow down into the substrate, which must be finegrained and kept clean to reduce the risk of infection. Bogwood and partially buried clean flowerpots should also be included in the tank. Chocolate Doradids are aggressive toward their own kind, so they cannot be housed together. They can, however, be kept with other species, especially those that swim at higher levels in the tank. There appear to be no records of this species being bred successfully in the home aquarium.

Butterfly Catfish (Hara hara)

• ORIGINS: Asia, where it occurs in northern India, Bangladesh, and Nepal.
• SIZE: 1 1⁄2 in (4 cm).
• DIET: Small live foods preferred.
• WATER: Temperature 64–82°F (18–28°C); soft (50–150 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Nonaggressive.

Though not often available, these small catfish make interesting aquarium occupants—they are social by nature and can be kept in groups. They are attractively and individually marked in various shades of brown, with some cream-colored areas on their bodies, too. The only drawback is that they are nocturnal and rather shy. Consequently, an aquarium for Butterfly Catfish should incorporate suitable retreats. Feed these catfish at dusk.

Indian Clown Catfish (Gagata cenia)

• ORIGINS: Southern Asia, occurring in northern India, Nepal, Pakistan, Bangladesh, and Myanmar (Burma).
• SIZE: 6 in (15 cm).
• DIET: Floating foods and live foods.
• WATER: Temperature 68–75°F (20–24°C); hard (100–150 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Nonaggressive.

This species is one of the Asian hillstream catfish, so it requires well-filtered and aerated water to mimic the conditions in a relatively fast-flowing stream. These fish will not harm vegetation, since they naturally feed on insects at the water’s surface. Consequently, it is better to give live foods (including freeze-dried items) and flake foods rather than sinking pellets. Indian Clown Catfish are lively, active fish and will thrive if kept in small groups.

Hancock’s Doradid (Platydoras hancockii)

• ORIGINS: Northern South America, ranging from Colombia eastward as far as Guyana.
• SIZE: 6 in (15 cm).
• DIET: Catfish pellets and live foods.
• WATER: Temperature 77–84°F (25–29°C); soft (50–150 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Nonaggressive

Dark, mottled-brown shades predominate in Hancock’s Doradid. These catfish belong to a group often described as talking catfish, because of their ability to make sounds by moving the spines of their pectoral fins. The resulting sounds are then amplified by the swim bladder. Hancock’s is a bubble-nesting species. It builds its nest among floating plants at the surface; the water level in the tank should be kept low to assist this process.

Black Doradid (Oxydoras niger)

• ORIGINS: South America, in the Amazon region, where it extends from Peru to parts of Brazil.
• SIZE: 30 in (80 cm).
• DIET: Catfish pellets, tablets, and live foods.
• WATER: Temperature 70–75°F (21–24°C); soft (50–100 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Peaceful, despite its large size.

This is not a species to acquire without careful thought about its future accommodation, since it will attain a very large size. This catfish also has a big appetite, especially when growing, so maintaining adequate filtration in the aquarium is essential for the health of both the catfish and any companions. Black Doradids are gentle, bottom-dwelling fish that will not trouble smaller species, although when frightened they may lash out powerfully with their tail. Their breeding habits are not documented.

THE SOUND OF SCALES

Members of the doradid group are well protected by the rows of protective spines along the body, which make these catfish difficult for predators to swallow. The spines on the pectoral fins are also used for communication—they produce an audible, scratchy sound when rubbed together. Exactly why doradids have evolved this method of communication is unclear, but since they are largely nocturnal, it may be that the sounds help them to locate each other for spawning purposes in the dark surroundings. It is possible that their welldeveloped sense of smell also assists them in their search for mates.

White-Spotted Doradid (Agamyxis pectinifrons)

• ORIGINS: South America, occurring in parts of Ecuador and Peru.
• SIZE: 6 in (15 cm).
• DIET: Catfish pellets and live foods.
• WATER: Temperature 68–79°F (20–26°C); soft (50–100 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Nonaggressive.

Whitish spots and blotches on a blackish background help to identify White-Spotted Doradids. Their tank should not be brightly lit and must include plenty of retreats where the catfish can hide. They will become more active when it is dark, emerging to hunt for food over the substrate. Like Hancock’s Doradid (see opposite), they can make sounds via the swim bladder. These catfish are probably substrate spawners, but breeding is unknown in aquariums.

Irwin’s Soldier Cat (Megalodoras uranoscopus)

• ORIGINS: South America, where it ranges through much of the Brazilian Amazon and into the Guianas.
• SIZE: 24 in (60 cm).
• DIET: Catfish pellets and meat-based foods.
• WATER: Temperature 72–79°F (22–26°C); soft (50–100 mg/l) and acidic to neutral (pH 6.0–7.0).
• TEMPERAMENT: Peaceful.

Not to be confused with the Black Doradid (see opposite), this snail-eating species does, however, attain a similarly large size, although it tends to grow more slowly. Its body is covered with very distinctive brown plates, overlaid in part with rows of spines, while darker shading helps to break up its outline. Snails make up the bulk of this catfish’s diet in the wild, augmented by palm fruits and other items that fall into the water. Fortunately, in the home aquarium it is possible to wean Irwin’s Soldier Cats onto artificial diets without much difficulty. It may be necessary to offer foods such as thawed shrimp at first, but before long, they should be eating tablets and similar prepared foods. These catfish need a large tank with secure decor that cannot be dislodged easily. The sharp projections on the body mean that it is unwise to transport this species in plastic bags, especially larger specimens.

Porthole Catfish (Dianema longibarbus)

• ORIGINS: Northwestern South America, in the Ambylac and Pacaya Rivers in Peru.
• SIZE: 4 in (10 cm).
• DIET: Prepared foods and live foods.
• WATER: Temperature 72–79°F (22–26°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Social and nonaggressive.

The pattern of dark speckling on the body varies between individual Porthole Catfish, but it never extends to the fins. Distinguishing the sexes is difficult, but pairs will breed in aquarium surroundings, where the male creates a bubble nest for the eggs. Lowering the water level and raising its temperature to 82°F (28°C) may help to trigger spawning. When swimming, the longer pair of barbels are held horizontally, while the shorter pair points downward.

Slender Armored Catfish (Callichthys callichthys)

• ORIGINS: South America, from Peru eastward to Guyana, eastern Brazil, Paraguay, and Bolivia.
• SIZE: 8 in (20 cm).
• DIET: Prepared foods and live foods.
• WATER: Temperature 64–82°F (18–28°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Social and nonaggressive.

The steeply sloping head of this catfish helps to distinguish it from corydoras, which have a similar reflective sheen on their bodies. Slender Armored Catfish are also significantly larger than corydoras and may prey on smaller companions in the aquarium. These catfish prefer naturally shady surroundings in which they can hide among bogwood and rocks during the day. They are primarily nocturnal in their habits and are most active toward dusk.

Thorocatum Catfish (Megalechis thoracata)

• ORIGINS: Northern South America, reaching as far south as Paraguay; also offshore islands, including Trinidad.
• SIZE: 8 in (20 cm).
• DIET: Prepared foods and live foods.
• WATER: Temperature 64–82°F (18–28°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Relatively peaceful.

This catfish is usually bluish-black or reddishbrown, with some speckling. Thorocatum Catfish are easy to sex when in breeding condition, since the rays of the male’s pectoral fins turn orange, while the underparts suffuse with a bluish-violet coloration. Spawning is very vigorous, with the male often pursuing the female aggressively. The eggs are deposited in a bubble nest at the surface among vegetation and will be guarded until they hatch. In the wild, this species inhabits muddy shallows that are thick with aquatic plant growth.

Spotline Aspidoras (Aspidoras lakoi)

• ORIGINS: South America, where it has been recorded in the state of Minas Gerais, Brazil.
• SIZE: 1 1⁄2 in (4 cm).
• DIET: Prepared foods and small live foods.
• WATER: Temperature 72–79°F (22–26°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Social and nonaggressive.

These small aspidoras catfish are closely related to the corydoras group and require similar care, although they are not as commonly available. In the Spotline, the silvery-bronze body is decorated with dark brown or black mottling, which in places forms rough horizontal lines. Dark lines also arc across the caudal fin. The key feature that sets aspidoras apart from corydoras is the presence of two pores in the skull (although these will obviously not be apparent in a live specimen). Spotline Aspidoras prefer to remain close to the substrate, which should be fine-grained so that they can dig into it. These fish will also appreciate the addition of bogwood and rockwork to their tank, especially small pieces of slate laid horizontally to create platforms on which the catfish can rest.

Sixray Corydoras (Aspidoras pauciradiatus)

• ORIGINS: South America, occurring in the Araguaia River, and the Rio Negro in Brazil.
• SIZE: 1 1⁄2 in (4 cm).
• DIET: Prepared foods and small live foods.
• WATER: Temperature 73–82°F (23–28°C); soft (50–100 mg/l) and acidic (pH 6.5).
• TEMPERAMENT: Social and nonaggressive.

A large blotched area on the dorsal fin identifies this mottled catfish, which also has a strongly marked caudal fin. Sixray Corydoras are not as well known as true corydoras; however, they are equally attractive, and it can sometimes be difficult to distinguish between the two species. The tank needs well-oxygenated water as well as a special sandy substrate in which the fish will instinctively dig for small worms and other edible items.

---