Mormyridae: Difference between revisions
m Reverted edits by 84.234.215.241 (talk) to last version by Hoopydink |
GrahamBould (talk | contribs) m Case, links |
||
| Line 13: | Line 13: | ||
}} |
}} |
||
The family '''Mormyridae''', sometimes called ''' |
The family '''Mormyridae''', sometimes called '''elephantfish''', are freshwater fishes native to [[Africa]] in the order [[Osteoglossiformes]]. It is by far the largest family in the order with around 200 species. |
||
Members of the family are popular, if challenging, [[aquarium]] species, notable for their ability to generate weak [[electric field|electric fields]] that allow the fishes to sense their environment in turbid waters where vision is impaired by suspended matter. The generation of these electric fields and their use in providing the fishes with additional sensory input from the environment is the subject of considerable scientific research, as is research into communication between and within species. |
Members of the family are popular, if challenging, [[aquarium]] species, notable for their ability to generate weak [[electric field|electric fields]] that allow the fishes to sense their environment in turbid waters where vision is impaired by suspended matter. The generation of these electric fields and their use in providing the fishes with additional sensory input from the environment is the subject of considerable scientific research, as is research into communication between and within species. |
||
Electric discharges are most often pulsitile discharges, with ''Gymnarchus niloticus'' being an exception to this rule, discharging its electric organ near approximately |
Electric discharges are most often pulsitile discharges, with ''[[Gymnarchus niloticus]]'' being an exception to this rule, discharging its [[electric organ]] near approximately 500 [[Hz]], giving it a near-[[sinusoidal]] like discharge. The electric organ is a structure that is well established in the scientific literature to be developmentally related to [[muscle]], as in [[Gymnotiform]] electric fish, as well as in electric rays and skates. There is a surprising degree of [[convergent evolution]] between the South American Gymnotiforms and the African Mormyridae, particularly in the sensory apparatus for detecting and processing electrical signals involved in [[electrolocation]] and [[electrocommunication]]. |
||
Some species possess modifications of the mouthparts to facilitate feeding upon small [[invertebrate |
Some species possess modifications of the mouthparts to facilitate feeding upon small [[invertebrate]]s buried in muddy substrates, the shape and structure of these leading to the popular name of "elephant nosed fish" for those species with particularly prominent mouth extensions. The extensions to the mouthparts (usually consisting of a fleshy elongation attached to the lower jaw) are flexible, and equipped with touch (and possibly taste) sensors. |
||
Among those members of the family lacking extended mouthparts, the body shape and general morphology of the fishes has led to some being known among aquarists by the name of |
Among those members of the family lacking extended mouthparts, the body shape and general morphology of the fishes has led to some being known among aquarists by the name of "baby whale", despite the fact that true [[whale]]s are [[mammal]]s. Other "mormyrid mammalian misnomers" include the term "dolphin fishes", in reference to certain members of the Genus ''Mormyrops''. |
||
==Classification== |
==Classification== |
||
| Line 58: | Line 58: | ||
* ''Marcunesias macrolepidotus''; |
* ''Marcunesias macrolepidotus''; |
||
* ''Marcunesias senegalensis''; |
* ''Marcunesias senegalensis''; |
||
* ''Pollimyrus castelnaui'', known among aquarists as the |
* ''Pollimyrus castelnaui'', known among aquarists as the "baby whale"', along with other relatives in the genus ''Pollimyrus''; |
||
* Pollimyrus isidori''; |
* ''Pollimyrus isidori''; |
||
* ''Brienomyrus niger'', the |
* ''Brienomyrus niger'', the "black baby whale"; |
||
* ''Campylomormyrus rhynchophorus''; |
* ''Campylomormyrus rhynchophorus''; |
||
* ''Hippopotamyrus discorhynchus''; |
* ''Hippopotamyrus discorhynchus''; |
||
* ''Mormyrops deliciosus'', a large member of the family utilised as a food fish by humans; |
* ''Mormyrops deliciosus'', a large member of the family utilised as a food fish by humans; |
||
* ''Petrocephalus catostomus'', the smallest member of the family (7 cm SL); |
* ''Petrocephalus catostomus'', the smallest member of the family (7 cm SL); |
||
* ''Mormyrus lapinus'', sometimes called the |
* ''Mormyrus lapinus'', sometimes called the "dolphin fish" or "freshwater dolphin" by aquarists; |
||
*''Brienomyrus brachyistius'', the |
*''Brienomyrus brachyistius'', the "brown baby whale" |
||
|} |
|} |
||
Revision as of 11:58, 16 August 2006
| Elephant fish | |
|---|---|
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| Order: | |
| Family: | Mormyridae
|
| Subfamilies | |
The family Mormyridae, sometimes called elephantfish, are freshwater fishes native to Africa in the order Osteoglossiformes. It is by far the largest family in the order with around 200 species.
Members of the family are popular, if challenging, aquarium species, notable for their ability to generate weak electric fields that allow the fishes to sense their environment in turbid waters where vision is impaired by suspended matter. The generation of these electric fields and their use in providing the fishes with additional sensory input from the environment is the subject of considerable scientific research, as is research into communication between and within species.
Electric discharges are most often pulsitile discharges, with Gymnarchus niloticus being an exception to this rule, discharging its electric organ near approximately 500 Hz, giving it a near-sinusoidal like discharge. The electric organ is a structure that is well established in the scientific literature to be developmentally related to muscle, as in Gymnotiform electric fish, as well as in electric rays and skates. There is a surprising degree of convergent evolution between the South American Gymnotiforms and the African Mormyridae, particularly in the sensory apparatus for detecting and processing electrical signals involved in electrolocation and electrocommunication.
Some species possess modifications of the mouthparts to facilitate feeding upon small invertebrates buried in muddy substrates, the shape and structure of these leading to the popular name of "elephant nosed fish" for those species with particularly prominent mouth extensions. The extensions to the mouthparts (usually consisting of a fleshy elongation attached to the lower jaw) are flexible, and equipped with touch (and possibly taste) sensors.
Among those members of the family lacking extended mouthparts, the body shape and general morphology of the fishes has led to some being known among aquarists by the name of "baby whale", despite the fact that true whales are mammals. Other "mormyrid mammalian misnomers" include the term "dolphin fishes", in reference to certain members of the Genus Mormyrops.
Classification
- Subfamily Mormyrinae
- Subfamily Petrocephalinae
Genera and Species
|
The family Mormyridae contains the following Genera: |
Among the species that belong to this family are:
|
Sources
- Froese, Rainer, and Daniel Pauly, eds. (2006). "Mormyridae" in FishBase. January 2006 version.
- One of several papers on electrogenesis and electric field sensing in Gnathonemus petersi
- Detailed research paper on the sensory and central nervous systems in Gnathonemus petersi
- Another page covering the electrosensory capabilities of Mormyrid fishes
- Mormyrids in the aquarium