''Perissodus microlepis'' is a species of
cichlid
Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses ( Labridae), in the order Perciformes, but molecular studies have contradicted this ...
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to
Lake Tanganyika
Lake Tanganyika () is an African Great Lake. It is the second-oldest freshwater lake in the world, the second-largest by volume, and the second-deepest, in all cases after Lake Baikal in Siberia. It is the world's longest freshwater lake. ...
. This species reaches a length of
TL. This species can also be found in the
aquarium
An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...
trade. It is a
scale-eating
Lepidophagy is a specialised feeding behaviour in fish that involves eating the scales of other fish. Lepidophagy is widespread, having evolved independently in at least five freshwater families and seven marine families. A related feeding behavi ...
'
parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
' on other fish species. It occurs in two distinct morphological forms. One
morph
Morph may refer to:
Biology
* Morph (zoology), a visual or behavioral difference between organisms of distinct populations in a species
* Muller's morphs, a classification scheme for genetic mutations
* "-morph", a suffix commonly used in tax ...
has mouth parts twisted to the left, enabling it to eat scales off its victim's right flank. In contrast, the other morph, whose mouth is twisted to the right, eats scales off its victim's left flank. The relative abundance of the two morphs in populations is regulated by
frequency-dependent selection Frequency-dependent selection is an evolutionary process by which the fitness (biology), fitness of a phenotype or genotype depends on the phenotype or genotype composition of a given population.
* In positive frequency-dependent selection, the fit ...
.
[Stewart, T. A. and Albertson, R. C. (2010]
"Evolution of a unique predatory feeding apparatus: functional anatomy, development and a genetic locus for jaw laterality in Lake Tanganyika scale-eating cichlids"
''BMC Biology'', 8 (1): 8. [Lee, Hyuk Je; Kusche, Henrik; Meyer, Axel (2012) Handed foraging behavior in scale-eating cichlid fish : Its potential role in shaping morphological asymmetry. PLoS ONE 7: e44670. ][Takeuchi Y, Hori M, Oda Y. (2012) Lateralized kinematics of predation behavior in a Lake Tanganyika scale-eating cichlid fish. PLoS ONE 7: e29272. ]
File:Dorsal view of right-bending and left-bending mouth morphs of the cichlid Perissodus microlepis - journal.pone.0044670.g001.png, Dorsal view of right-bending (left) and left-bending (right) mouth morphs
References
{{Taxonbar, from=Q2701161
Perissodus
Articles containing video clips
Taxa named by George Albert Boulenger
Fish described in 1898
Taxonomy articles created by Polbot