Home
 What's New
 About
 Preface
 Introduction
 Fish Anatomy
 Water Chemistry
 The Aquarium
 Plant Care
 Plant Species
 Food
 Disease
 Biotope Aquaria
   Ecosystems
   Country Database
 Fish Species
   Catfish
   Characins
   Cichlids
   Cyprinds
   Killifish
   Labyrinth Fish
   Livebearers
   Loaches
   Others
   Perches
   Rainbowfish
 Non-fish Species
 Breeding Fish
 Aquarium Photos
 Languages
   Chinese
   Finnish
   Japanese
 Bibliography
 Links
 Resources
 Rainforests
 Books
 Mongabay Sites
   Kids site
   Travel Tips
 News
 Contact




OTHERS


MORMYRIDAE FAMILY
The Mormyridae or Elephant-nose family consists of 18 genera and 200 species. Mormyridsare distinguished by their snout which often is extended into a proboscis. The caudal penuncle serves as the sitefor a weak electrical organ used in orientation.Using this organ, Mormyrids are able to communicate with each other,find prey, and detect predators is murky waters or at night. Mormyrids have a large brain-nearly equal inthe body weight to brain weight ratio of humans.Most Mormyrids are nocturnal or crepuscular species.

Long-nosed Elephant Fish, Elephant Nose, Peter's Elephantnose
[ Pictures ]
Gnathonemus petersii
SYN : Mormyruspetersii, Gnathonemus pictus
PD : This species has an elongated, laterally compressed body. The Elephant Nose has a small roundmouth that is located above its trunk-like extension or proboscis. The dorsal and ventral profiles aresymmetric with the anal and dorsal fins being located across from one another. The caudal fin is forked. Thecoloration is black or blackish-brown with two yellowish-white stripes extending vertically between the dorsaland anal fins.
SIZE : To 9" (23 cm)
SS : Other Gnathonemus species.
HAB : Moving water, often muddy, near submerged wood in West and Central Africa; Zaire,Nigeria, Cameroon .
S : bottom, middle
TANK : A 30" (76 cm) or 25-30 gallon (95-114 L) is sufficient, although larger tanksare required for individuals exceeding 6" (15 cm) in length. The tank should be well-planted and muted lightingshould be used.Provide overturned flower pots, pipes, caves, or tubes for each fish to serve as a retreat. Usefine gravel or sand as a substrate.Furnish the tank with wood and rocks.
WATER : pH 6-7.2 (6.7), 3-12 dH (7), 73-82°F (23-28°C)
SB :The Elephant Nose is peaceful with other community fish, but territorial with others ofits own species.Do not combine with aggressive species (Cichlids) for the Elephant Nose may not be ableto compete for food.Do not keep in pairs as the weaker fish may be harassed. The Elephant Nose can be combined ingroups of three or more because the aggression is dispersed. A nocturnal species.
SC : Congo Tetra, Synodontis , Characins, Killifish, Eartheaters, Angelfish, African Butterfly fish, West African Cichlids
FOOD : Live; Tubifex , other worms, insect larvae , Artemia; occasionally flakes. Feedafter the lights are off.
SEX : No obvious external differences, the electric organ discharge (EOD) in G. petersii is used in sexual identification.
B : According to Dr Robert Landsman of ANOVA Science Education , one reason that this species has not been bred in captivity is that the electric signals of males and females sex reverse so that males send out female-like (shorter shaped) signals and females send out male-like (longer shaped) signals when they are brought into captivity. Thus, captivity induces signal sex-reversal so that the fish probably cannot communicate between genders appropriately. Learn more >
BP : 10.This species has not been bred in captivity.
REMARK S :The Long-nosed elephant fish has an electrical organ which it uses to find its food. It'sbrain size to body weight ratio is higher than that of humans. Unlike man, it's cerebellum is larger than it'sfront brain.The Long-nosed elephant fish is used by water departments in the U.S. and Germany to test the qualityof drinking water.When the quality of the water declines the amount of electrical pulses released increases. Sincethe Long-nosed elephant fish has very poor vision, it uses the trunk or proboscis to locate it's food. Elephant-nose fish are depicted in ancient Egyptian tombs dating from around 2500 BC. Always use a good water conditioner for this sensitivespecies.They are often intolerant of fish medications.
DC : 5.This interesting species requires live foods and well maintained water.

Worm-jawed Mormyrids; Blunt-Jaw Elephantnose [ Pictures ]
Gnathonemus tamandua
SYN : Campylomormyrustamandua, Gnathonemus elephas, Mormyrus tamandua
PD : An elongated, laterally compressed species. The Blunt-Jaw Elephantnose's mouth islocated near the end of its large proboscis.The lower part of the proboscis protrudes past the mouth. Thedorsal and ventral profiles are symmetric with the anal and dorsal fins being located across from one another. Thecaudal fin is forked.The coloration is brown-gray with several brownish-white markings.
SIZE : To 16" (40 cm)
SS : Other Gnathonemus and Campylomormyrus species.
HAB : In murky water with submerged wood in Western Africa ; Niger and Zaire.
S : bottom
TANK : A tank measuring 48" (122 cm) with a capacity from 55 gallons (209 L) is sufficientfor fish to 10" (25 cm) in length.Larger fish require larger tanks. Use dim lighting and provide hidingplaces with pipes, tubes, caves, and wood.The tank should be well-planted with large, robust plants and havea cover of floating plants.Use a filter that provides a strong current. Use a fine gravel or sand substrate,for this fish burrows.The Worm-jawed Mormyrid prefers large, shallow tank having peat filtration.
WATER : pH 6.0-7.5 (6.8); 5-20 dH (6); 73-82°F (23-28°C)
SB : A species that is territorial and aggressive towards similar species although peacefultowards different large species.Do not combine with small species.
SC : Haplochromis,Synodontis, Cichlasoma, Tilapia, Pimelodids, Doradids, Loricarids,African characins.
FOOD : Live; Tubifex , small fish, worms, insect larvae
SEX : The rear edge of the anal fin of males is curved, while the edge of females is straight.
B : Unknown
BP : 10.This species has not been bred in captivity.
REMARK S : This species requires frequent partial water changes.
DC : 7.The Worm-jawed Mormyrid is a fairly difficult species to care for. It requires live foods and is aggressive. Itis sensitive to medications and unfavorable water conditions.

Large-scaled Mormyrid, Bulldog [ Pictures ]
Marcusenius macrolepidotus
SYN : Gnathonemusmacrolepidotus, Mormyrus macrolepidotus
PD : An elongated, laterally compressed species with a long, slender caudal penuncle anda forked caudal fin.The anal and dorsal fins are located opposite one another and are situated far back onthe body.The forehead is large and rounded and there is lobe on the lower jaw. The color is light brown to dark graywith a silver iridescence.The body may be spotted with irregular brown spots.
SIZE : To 12" (30 cm) in nature, although rarely larger than 8" (20 cm) in captivity.
SS : Marcusenius species, and Hippopotamyrus species.
HAB : Southern Africa; widespread in the Cunene, Okavango, upper Zaire, and Zambezi riversystems.
S : bottom, middle
TANK : A 40" (101 cm) or 45-55 gallon (170-209 L) tank is sufficient. Follow suggestions for G. petersii.
WATER : pH 6-8 (7.5), 5-18 dH (10), 68-79°F (20-26°C)
SB : A territorial species that is aggressive towards similar fish. It is possible to maintain this species;species is a school of six or more in a large tank.A nocturnal species.
SC : Gouramis, Barbs, Synodontis, West African Cichlids, African characins
FOOD : Live; Tubifex , other worms, insect larvae , Artemia; occasionally flakes. Feedafter the lights are off.
SEX : Skelton (98) reports that males have a notch in their anal fin, while females do not.
B : Has not been accomplished in aquaria, although has been observed in nature. Accordingto Skeleton (98), this species spawns during the rainy season is shallow, planted areas. As many as 6000 eggs are laid.
BP : 10.Breeding has not been accomplished in aquaria, although may be possible by recreating therainy season in a large tank.
REMARK S : Mass migrations in nature have been reported, although these have not been linkedto the spawning season.
DC : 6.This large species requires live foods and a well-maintained tank.

Baby Whale
[ Pictures ]
Pollimyrus isidori
SYN : Mormyrusisidori
PD : A bullet-shaped species with strong lateral compression and a long, slender caudalpenuncle.The head and snout are rounded and the mouth is small. The anal and dorsal fins are locatedfar back on the body and are opposite one another. The body color is light gray to gray-brown and can be speckledwith small dark spots.The fins are brown and the caudal fin is forked. A faint red stripe extends from thecaudal penacle to the gill cover.
SIZE : To 6" (15 cm) in nature, although rarely larger than 3.5" (9 cm) in captivity.
SS : Marcusenius species, Hippopotamyrus species, Petrocephalus species, and other Pollimyrus species.
HAB : Africa; Lower Nile, Upper Zambezi
S : bottom, middle
TANK : A 28" (71 cm) or 20-25 gallon (76-95 L) tank is sufficient. Follow suggestions for G. petersii.
WATER : pH 6-8 (7.5), 4-18 dH (10), 77-84°F (25-29°C)
SB : A peaceful, schooling fish recommended for a community tank. This species should be kept singly orin groups of five or more.It is important to provide a retreat for each fish. Larger Mormyrids tends to harass thisgentle, but territorial species.A nocturnal species.
SC : See M.macrolepidotus.
FOOD : Live; Tubifex , other worms, insect larvae , Artemia; occasionally flakes. Feedafter the lights are off.
SEX : Unknown
B : Unknown
BP : 10.Breeding has not been successful.
REMARK S : An easy fish to keep, although it is sometimes intolerant of unfavorable waterconditions.
DC : 5.This interesting species requires a diet of live foods.


Species Index | Fish Home | Rainforests




Recent news

Baltic cod are shrinking due to overfishing
(8/26/2008) By comparing Neolithic cod with contemporary cod, researchers have discovered that the species has evolved over a relatively short period due to overexploitation by humans. According to a paper published in Proceedings of the Royal Society B, contemporary cod attain adulthood earlier and are generally smaller than their ancestors.

DNA study reveals new 1,000-pound grouper species
(8/21/2008) DNA analysis has revealed that a 1,000-pound grouper found in both the Atlantic and Pacific Oceans is actually two different species.

Coal burning may make food supplies toxic
(8/18/2008) Coal burning is contaminating the Arctic, and may be affecting human health and polar ecosystems, warn scientists writing in the online early edition of the Proceedings of the National Academy of Sciences.

The long-ignored ocean emergency and what can be done to address it
(8/18/2008) This year has been full of bad news regarding marine ecosystems: one-third of coral species threatened with extinction, dead-zones spread to 415 sites, half of U.S. reefs in fair or bad condition, increase in ocean acidification, tuna and shark populations collapsing, and only four percent of ocean considered pristine. Jeremy Jackson, director of the Scripps Center for Marine Biodiversity and Conservation at the University of California, San Diego, synthesizes such reports and others into a new paper, published in the journal Proceedings of the Naional Academy of Sciences, that boldly lays out the scope of the oceanic emergency and what urgently needs to be done.

How sustainable is your canned tuna? It depends on the retailer
(8/13/2008) To aid concerned tuna-lovers, Greenpeace has ranked eight of the top canned tuna retailers in order from most sustainable to least. Canned tuna from John West, the biggest retailer of tuna in the UK, proves to be the worst of the lot, whereas Salinburys is the most environmentally-friendly. In a press release Greenpeace said that Salinburys is "the only tinned tuna brand that is fished using sustainable methods".


what's new | tropical fish home | rainforests | news | search | about | contact



Copyright Rhett Butler 1994-2006

The copy for fish.mongabay.com was written in 1994-1995. Therefore some information such as scientific names may be out of date. For this, I apologize. Feel free to send corrections to me.