Egg-laying tooth carps
The division of living beings into systematics is a continuous subject of research. Different systematic classifications exist side by side and one after the other. The taxon treated here has become obsolete due to new research or is not part of the group systematics presented in the German-language Wikipedia.
The egg-laying toothcarps (also killifish ) are a group within the toothcarps that enjoy great popularity in the aquarium hobby. Traditionally, one expects, the species from the families Cyprinodontidae , Aplocheilidae , Fundulidae , Profundulidae , Rivulidae and Valenciidae and the as lampeyes subfamilies designated Aplocheilichthyinae and Procatopodinae that until recently, along with the live-bearing tooth carp family Poeciliidae were counted; the viviparous toothcarps are now again a family of their own, which originally only existed in America.
origin of the name
The name "egg-laying toothcarps" comes from the time when the toothcarps were divided into livebearers and egg-laying toothcarps .
The first killifish were found in the drainage ditches (the so-called kills ) of the Dutch colonies in North America. It was a variant of the egg-laying tooth carps. After some time, the term was also used for other fish that inhabited similar habitats. After all, it was used as a substitute for all egg-laying toothcarps.
The classification is now out of date from a phylogenetic point of view. But the names are still very important among aquarists. In contrast to the viviparous toothcarps, the egg-laying toothcarps are exotic, which you can usually only get in specialized shops. In the "German Killifisch Gemeinschaft" many lovers of these fish are also organizationally connected.
Subdivision
Collective names have been established in aquaristics for different groups of killifish, but they are not the name of a taxon .
Such groups are
- the splendid carbines with the genera Aphyosemion , Archiaphyosemion , Callopanchax , Chromaphyosemion , Diapteron , Fundulopanchax , Scriptaphyosemion ;
- the Prachtgrundkärpflinge with the genera Fundulosoma , Nothobranchius and Pronothobranchius ;
- the pike with the genera Aplocheilus , Epiplatys , Pachypanchax , Pseudepiplatys (with Pseudepiplatys annulatus as the only representative) and
- the light-eye fish with the subfamilies Aplocheilichthyinae and Procatopodinae .
The genera included in these groups, however, by no means represent the sum of all killifish, in addition there are, for example, the American species of the Rivulidae family including the brookling ( Rivulus ) and Eurasian killifish.
distribution
Egg-laying toothcarps are found in over 770 species on all continents with the exception of Australia.
Mediterranean fish only occur in the regions around the Mediterranean , where they also colonize brackish water biotopes.
The most colorful species come from the tropical regions of Africa and America, where most of them inhabit small streams and rivulets. Some of the African and American species are seasonal ; That is, they only live in the rainy season and lay permanent eggs that survive the dry season while they themselves perish at the end of the rainy season. They also live in stagnant water. Within the deposited spawn there is usually an (exponentially decreasing) number of eggs that can survive further drought to be on the safe side. However, this differs from species to species. The maximum storage time can be up to three years.
Killifishes in the aquarium hobby
Male killifish in particular are extremely colorful and beautifully drawn, which explains their popularity with aquarists.
Most killifish live solitary. They are quite aggressive towards other species as well as towards alien fish, which is why they should preferably be kept in a species tank. There it is recommended to keep one male with several females. In larger tanks, several males can usually be kept together.
The light-eye fish of Africa are schooling fish and are much better tolerated (but also less colorful).
All killfish are warm water fish, most prefer temperatures around 23 ° C. Exceptions are some American species ( desert parsnips ), some of which are adapted to temperatures above 35 ° C and thus occupy quite unusual ecological niches. A large part of the killifish is characterized by high jumping ability. Young fish, especially the African Nothobranchius group, but also others, have a very high growth rate. Under favorable conditions, it can take three to four weeks from hatching to sexual maturity. Depending on the environmental conditions, extremely shifted gender relations can occur. All Fundulupanchax species can be crossed with each other.
The fact of permanent eggs is used in the aquarium hobby because they - wrapped in moistened peat - can be conveniently sent by post to other aquarists around the world.
literature
- Norbert Dadaniak, Reinhard Lütje, Wolfgang Eberl: The fascination of killifish: the "Aphyosemion cameronense" group . 1995.
- Lothar Seegers: Killifishes. Egg-laying tooth carps in the aquarium. 1980.