Mouthbrooders

Mouthbrooding male of the gourdfin cardinalfish . The strongly bulging throat pouch is easy to see

Mouth brooding chocolate gourami

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Spawning and egg picking in Burton's mouthbrooders

Mouthbrooding female of Pseudocrenilabrus nicholsi (foreground)

Darwin's nose frog ( Rhinoderma darwinii )

As mouthbrooders referred to fish or amphibians , which the fertilized for protection against enemies eggs take or hatched young in their mouths. A distinction is made between ovophilic (“egg-loving”) and larvophilic (“larva-loving”) mouthbrooders. With maternal mouth brood care, the female takes the brood in the mouth, with paternal care the male. Both parent animals participate in biparental mouthbrood care. External fertilization takes place in mouth-brooding fish.

Breeding effort

The advantage of mouth brooding is that in the event of a threat it is possible to move quickly with the clutch, a possibility that substrate spawners do not have. The disadvantage is the smaller clutch due to lack of space. The reduction in the number of eggs means energy savings, especially for the female fish.

Mouth brood itself, however, often requires renunciation, some species do not eat during this time (such as Banggai cardinalfish ), perhaps in order not to devour their brood. In the Tanganyika bulge head , the stomach filling was examined. Mouth brooding females had only 19–28 percent filling of the stomach compared to females not engaged in mouth brooding. Cannibalism has been observed in the Japanese cardinalfish Ostorhinchus doederleini , an ovophilic paternal mouthbrooder, which usually does not consume food during this time, and in the multicolored mouthbrooder ( Pseudocrenilabrus multicolor ), an ovophilic maternal cichlid; in the latter case, unfertilized eggs are preferred. Brooding multicolored mouthbrooders need 15.7% more energy than non-breeding ones. Breeding females of the subspecies Pseudocrenilabrus multicolor victoriae spend more time on the oxygenated surface in oxygen-poor water than non-breeding females .

In some species, the mouthbrooder only ingests food to nourish its larvae, such as Tropheus moorii .

fishes

Mouth-brooding fish are found in the following taxa :

• Cardinalfish (Apogonidae): all paternal mouthbrooders.
• Cross catfish (Ariidae): predominantly paternal mouthbrooders.
• Claroteidae : only one species of biparental mouth brooding ( Phyllonemus filinemus ).
• Snakehead fish (Channidae)
• Cichlid (Cichlidae): numerous examples of mouthbrooders can be found among the cichlids, especially in the species found in the African Great Lakes (e.g. Lake Malawi , Lake Tanganyika ), mostly maternal (but Sarotherodon melanotheron paternal), some biparental.
• Knife eels (Gymnotidae): only one paternal mouth-brooding species is known ( banded knife eel ( Gymnotus carapo )), but overall reproduction is little known.
• Pine fish (Opistognathidae): predominantly paternal mouthbrooders.
• Osphronemidae : some species practice paternal mouth brooding.
• Bonytongues (Osteoglossidae): predominantly paternal mouthbrooders.
• Miracle perch (Plesiopidae): paternal mouth brood in the genus Assessor .

In the sea, mouth brooding as a form of brood care is much less widespread than with freshwater fish . Most of the marine mouthbrooders are ovophilic and no longer care about the hatched fry. An exception is the Banggai cardinal perch ( Pterapogon kauderni ), in which the male carries the embryos in its mouth for 6 days after the eggs have hatched.

Amphibians

There is also a mouthbrooder among the amphibians: in the Chilean Darwin nosed frog ( Rhinoderma darwinii ), the eggs are first laid on land and guarded by the male. The hatching tadpoles are then taken up by the male in his throat pouch in order to complete the development there.

evolution

The mouth brooding developed several times in parallel , based on the hiding-place spawners . In cichlids alone, it is assumed that this brood care developed 10 to 14 times, but the possible phylogenetic tree is controversial. DNA analyzes show that the behavior changes took place in evolutionarily very short periods of time.

Parasitism

Synodontis multipunctatus from the East African Lake Tanganyika operate brood parasitism and smuggle their eggs spawning cichlids under. The cichlid then treats the catfish eggs like its own and also guards the young. Since the cuckoo whiskered catfish are more likely to hatch, they take the opportunity to eat their host's eggs in its mouth before leaving its mouth.

literature

• Ellen Thaler : mouthbrooders in reefs and aquariums . KORALLE, marine aquaristic specialist magazine, No. 54 December / January 2008/2009, Natur und Tier Verlag Münster. ISSN  1439-779X

Web links

Commons : Mouthbrooding  - collection of images, videos and audio files

Individual evidence

1. ↑ Y. Yanagisawa, H. Ochi: Food intake by mouthbrooding females of Cyphotilapia frontosa (Cichlidae) to feed themselves and their young. In: Environmental Biology of Fishes . 30, 1991, pp. 353-358.
2. ^ Noboru Okuda, Yasunobu Yanagisawa: Filial cannibalism in a paternal mouthbrooding fish, Apogon doederleini, in relation to mate availability. In: Animal Behavior 52, No. 2, 1996, pp. 307-314.
3. ↑ Wolfgang Mrowka: Filial cannibalism and reproductive success in the maternal mouthbrooding cichlid fish Pseudocrenilabrus multicolor. In: Behavioral Ecology and Sociobiology . 21, No. 4, 1987, pp. 257-265.
4. ^ W. Mrowka, B. Schierwater: Energy expenditure for mouthbrooding in a cichlid fish. In: Behavioral Ecology and Sociobiology . 22, 1988, pp. 161-164
5. ↑ LW-C. Corrie, LJ Chapman, EE Reardon: Brood protection at a cost: mouth brooding under hypoxia in an African cichlid. In: Environmental Biology of Fishes . 82, 2008, pp. 41-49.
6. ↑ Y. Yanagisawa, T. Sato: Active browsing by mouthbrooding females of Tropheus duboisi and Tropheus moori (Cichlidae) to feed the young and / or themselves. In: Environ. Biol. Fish. 27, 1990, pp. 43-50.
7. ↑ Haruki Ochi, Andrew Rossiter, Yasunobu Yanagisawa: Biparental mouthbrooding of the catfish Phyllonemus filinemus in Lake Tanganyika. In: Ichthyological Research 48, No. 3, 2001, pp. 225-229.
8. ^ GF Turner, RL Robinson: Reproductive biology, mating systems and parental care. Tilapias: biology and exploitation. In: Fish and Fisheries Series 25, 2000, pp. 33-58.
9. ↑ WGR Crampton, CD Hopkins: Nesting and paternal care in the weakly electric fish, Gymnotus (Gymnotiformes: Gymnotidae) with descriptions of larval and adult electric organ discharges of two species. In: Copeia , 1, 2005, pp. 48-60.
10. ↑ Alejandro Vagelli: The reproductive biology and early ontogeny of the mouthbrooding Banggai cardinalfish, Pterapogon kauderni (Perciformes, Apogonidae). When do fishes become juveniles? In: Developments in Environmental Biology of Fishes 19, 1998, pp. 79-92.
11. ↑ AmphibiaWeb: Information on amphibian biology and conservation. 2013. Berkeley, California: Rhinodermatidae
12. ↑ NS Balchine-Earn Goodwin, J. Reynolds: Evolutionary transitions in parental care in cichlid fish. In: The Royal Society . 265, 1998, pp. 2265-2272.
13. ↑ Michael R. Kidd, Nina Duftner, Stephan Koblmüller, Christian Sturmbauer, Hans A. Hofmann: Repeated parallel evolution of parental care strategies within Xenotilapia, a genus of cichlid fishes from Lake Tanganyika. In: PloS one 7, No. 2, 2012, e31236, doi: 10.1371 / journal.pone.0031236 .
14. ↑ E. Schraml: Fiederbart catfish from Lake Tanganyika. In: DATZ , 56, No. 8, 2003, pp. 60-65.