Welcome to the Mormyridae and other Osteoglossomorpha. This is the first part, dealing with the weakly electric Mormyridae and Gymnarchidae, fish families confined to Africa.
In order to enhance the understanding of this peculiar group of fishes, their next relatives of the Superorder Osteoglossomorpha and some other electric fishes are also briefly introduced. First of all the strongly electric ones, on which the phenomenon of bio-electricity has been experienced first and which had great influence on the development of our general knowledge of the functions of muscles, nerves and the central nervous system.
This project is dealing with the taxonomy of the family Mormyridae and its two subfamilies Petrocephalinae and Mormyrinae and the monospecific family Gymnarchidae, all in all 187 species. Because most of the species are only known to specialists and by museum specimens, I confined to the type specimens, of which I have a practically complete collection of photographs. This seemed to be necessary since very few species only have been imported to Europe or America and with it but very few pictures of living animals are available.
Each photography of a type is accompanied with an outline drawing to show the main characters of the taxon, inclusive the number of fin-rays and the number of scales along the lateral line and around the caudal peduncle. And of course, whenever possible I have added a picture of a live specimen.
Confining to types, so I hope, may have the advantage that everybody interested in Mormyrids will have the opportunity to see at least one type without the need to visit a museum. This may also be advantageous to the types, for there is no longer a need to handle them, in particular since I added the main measurements of every type, almost all made by myself, which also means applying the same method of measuring. Not the least, in case types should get lost, as happened in 1978 when the Lisbon museum burned down, an authentic photograph still will be at hands and certainly will do better than a drawing, even if it is of best quality.
For the non-mormyrid Osteoglossomorpha there was no need to look up the type-specimens and to confine to the types. Most genera are monospecific and of characteristic body-form anyway, so there is little chance to confuse the species if one sees a picture or a live specimen and/or follows the taxonomic description supplied here.
The taxonomy of higher taxa has been subject of many changes from the very beginning of taxonomy. I tried to present the most recent interpretation of the interrelationship of the Mormyridae and Gymnarchus , which to me seems to be the most reasonable one, based on several approaches to clarify the subject.
This work, however, also bases on the respective chapters of the Checklist of the freshwater fishes of Africa (CLOFFA) by J.-P. Gosse, 1986; without it it would have been much more difficult to prepare.
Wilhelm Harder,
Zoologisches Institut der Eberhard-Karls-Universität
Tübingen, Germany.
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Please keep in mind that the Mormyridae and other Osteoglossomorpha programme is, like all science, a "work in progress". We actively solicit comments, corrections and additions from our users for incorporation in version 2.0 of this software.