Erpetoichthys calabaricus – Reedfish
The Reedfish (Erpetoichthys calabaricus) belongs to the family Polypteridae. It is a family of primitive fish. Fossils of Polypteridae have been found in rocks dating from 206-248 million years ago, the beginning of dinosaur development.
These ‘living fossils’ are found in much of Africa. Erpetoichthys calabaricus is the only species within the genus Erpetoichthys. They have a cylindrical elongated body, resembling an eel or snake. It is equipped with a scale armor. The pectoral fins are exactly where you would expect the legs to be in a lizard. The fish has up to 11 fin rays on the back, without fins.
The Reedfish was described by Smith as early as 1865. In the course of time, it has already seen many names. Synonyms are Calamoichthys calabaricus, Herpetoichthys calabaricus, and Erpetoichthys robbianus. It has several common names like Reedfish, Ropefish, or Snakefish
The swim bladder has evolved into a primitive lung, which allows the fish to use air from the surface. Combined with the gills, they have two ways of breathing in order to survive in oxygen-poor water. Even if the oxygen content in the water is sufficient, they will regularly swim to the surface for a mouthful of air. They will drown if it does not have access to atmospheric air.
Young specimens, just like salamanders, have clearly visible external gills. Although the ability to gasp for air gives the animal a perfect survival kit, it also introduces some problems. Since they have to surface at regular intervals, they are easy prey for snakes, birds and predatory fish. For this reason, they are perfectly camouflaged in body color and shape, making them completely absorbed in their habitat from above. When hunted, they can completely burrow into the sand within seconds.
The skin is covered with a strong scale armor. The scales are triangular, with a hook at the end, and covered with a hard and tough material that also prevents water loss outside the water.
Erpetoichthys calabaricus has poor eyesight and largely follows scent trails to find food. For this, they are equipped with tubular nasal openings. Prey are slowly stalked and swallowed up close. The Reedfish has two plate-like bone structures in the lower jaw that help it chew food.
A Reedfish can survive outside the water for several hours and in humid conditions for up to 2 days. The fish then propels itself over land with its pectoral fins. Erpetoichthys calabaricus has been swimming in waters all over the continent for 70 million years. They are still found in West Africa, between Nigeria and the Congo. This includes Congo, Angola, Nigeria, Cameroon, Guinea and Benin. They grow to a maximum length of 45 centimeters and live in still or lightly flowing water, which can also be brackish. They are nocturnal and mainly feed on annelids, crustaceans, and insects.
The cautious character, the slow and graceful movements and the patient tracking by scent leave a pleasant and harmless impression. Appearances are deceiving: a hungry Reefdish can suddenly launch itself at high speed at prey.
Reedfish Sexual Dimorphism
The males of Erpetoichthys calabaricus have 12-14 fin rays, and females have 9.
The curious appearance, healthy hunger, and hardiness make the Reedfish a species that is easy to care for and for a very long period of time. They are calm, swim quite a lot, and are just as often hidden. They are territorial but never bother other fish. However, smaller, especially more elongated, fish run a high risk of being swallowed. The Reedfish’s eyesight is poor. The prey is slowly stalked by a combination of chance and sense of smell and swallowed up close. There are also never chases on the prey. However, if necessary, they can quickly propel themselves forward. They are a social species that feel more comfortable in a group.
An aquarium with open spaces combined with a lot of shelter in the form of plants, rocks or wood. Slightly dimmed light makes them feel more at ease and more active. They are powerful, muscular fish that like to hide and forage in the vegetation, so it is advisable to secure plants well. Caves in which they can hide contribute to their well-being. The height of the waterline is not important, the bottom surface is.
Younger Erpetoichthys calabaricus can be kept in a smaller aquarium from 80 centimeters. However, they grow quickly, after which a larger tank is of course necessary. Think of an aquarium with a minimum length of about 160 centimeters.
Cover the aquarium tightly and check that there are no cracks or openings in the hood: they are true escape artists. With sufficient strength in the body, they are able to push cover plates and light hoods upwards. Furthermore, make sure they have the ability to draw air from the surface.
Suitable tankmates for Reedfish are primarily fish that do not fit in their mouths. These include:
- Kwastvinsnoeken (bij voorkeur niet te groot)
- Klimbaarzen van de soort Ctenopoma
- African Butterfly Fish (Pantodon buchholzi)
- Large Congo tetras
- Cicliden van de soort Pelvicachromis
- Large Synodontis catfish
- African Knifefish (Xenomystus nigri)
Houd de Wimpelaal niet met agressieve vissoorten, zoals territorium vormende cichliden, slangenkopvissen (Channa) en vissoorten uit de Labeo familie. De dieren zijn namelijk niet tegen agressie bestand. Ook de combinatie met meervallen voorzien van een zuignap (bijvoorbeeld Plecostomus), werkt niet aangezien de meervallen het pantser van de Wimpelaal begrazen en daarmee vernielen. Houdt de vis ook niet met dieren die in korte tijd als het voedsel wegkapen. Wimpelalen zijn terughoudend van aard en vinden voedsel op reukvermogen. Ze zijn daardoor niet snel bij het voedsel en verhongeren bij voedselconcurrentie. De dieren zijn verder gesteld op een constante watersamenstelling. De Wimpelaal staat ook als brakwatervis geregistreerd. Het zoutgehalte mag echter nooit 1.005 overschrijden.
The Reedfish is a carnivore. Feeding is not difficult, they are not picky. Pieces of beef, fish, shrimp, mysis, mosquito larvae, and earthworms work well. Weening them to dry food or frozen food is more difficult. Many specimens do not get used to it.
Mating takes place while swimming parallel. The female deposits a number of eggs between the male’s anal fins, where they are fertilized and released into the vegetation. They stick to the vegetation. This is repeated many times. The larvae hatch after 70 hours and remain on the vegetation. 22 days after hatching, the yolk sac is empty and the larvae begin to feed.
Buying a Wimpelaal is not always easy. They are not always available in the store, but they can often be ordered. Before you buy, ask if they want to feed the fish so that you can be sure that it will still accept food. Healthy Reedfish are full of energy and swim around happily. If they have white spots or spots on their bodies or if the eyes are not clear, do not buy the fish. Take a look at the fish (and its fellow inhabitants) before you buy the Reedfish.
P. de Pijper