The Knysna banana frog (''Afrixalus knysnae'') is a species of

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

in the family Hyperoliidae. It is

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 South Africa.

Habitat

Its natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s are temperate

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

s, Mediterranean-type shrubby vegetation, freshwater

marsh A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at ...

es, intermittent freshwater marshes,

arable land Arable land (from the la, arabilis, "able to be ploughed") is any land capable of being ploughed and used to grow crops.''Oxford English Dictionary'', "arable, ''adj''. and ''n.''" Oxford University Press (Oxford), 2013. Alternatively, for the ...

, water storage areas, and

pond A pond is an area filled with water, either natural or artificial, that is smaller than a lake. Defining them to be less than in area, less than deep, and with less than 30% emergent vegetation helps in distinguishing their ecology from th ...

s. It is threatened by

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

. The Knysna banana frog is a species known from around 7 locations at low altitude (< 250 m asl) on the south coast of South Africa on either side of the border between the Eastern Cape and Western Cape provinces. To the extent of scientists knowledge we know that the occurrence rate is 1,756 km². The area of occupancy has not been formally calculated but is known to be declining as some sites (like Covie) are presumed lost as no adults or tadpoles have been found there for at least three years. Although some sites are pristine, others are threatened by alien vegetation. Banana frogs are native to South Africa (Eastern Cape Province, Western Cape Province). They live in coastal mosaic of vegetation types, including mountain fynbos heathland, and forest. The frogs breed in small dams and shallow semi-permanent water with much emergent vegetation and even in well vegetated ornamental garden ponds; it is suspected that this species requires high water quality for breeding. Habitat is declining due to encroachment by urban development, alien invasive vegetation and chemical pollution. Species in this genus deposit between 20 and 50 eggs on vegetation above the water. Tadpoles emerge, drop into the water and remain there until metamorphosis.

Identification

The Knysna banana frog has a creamy and yellow color with lateral brown stripes. Females have a smoother texture than males.

Population

Population trends are unknown: since there has been a rapid decline in population it is hard to tell if urban development, alien invasive vegetation, chemical pollution, or a combination of these have been the sole reason of the decline and therefore affect the population trend. The distribution of the species tends to be severely fragmented as no one site holds more than 50% of the individuals and the distances between subpopulations are too great for dispersal within one generation. When scientists visited a site at Covie they found that the frogs have not produced any individuals (adults or tadpoles) for three years. It seems likely that this subpopulation has become extinct, but further visits are required to substantiate this; just because this area seems to be extinct does not mean the entire species is extinct. The cause for this disappearance is as yet unknown, but change in water quality is suspected as a possible reason. This is most likely due to urbanization. The main threat is habitat loss due to

urban Urban means "related to a city". In that sense, the term may refer to: * Urban area, geographical area distinct from rural areas * Urban culture, the culture of towns and cities Urban may also refer to: General * Urban (name), a list of people ...

and recreational development,

afforestation Afforestation is the establishment of a forest or stand of trees (forestation) in an area where there was no previous tree cover. Many government and non-governmental organizations directly engage in afforestation programs to create forests a ...

invasive vegetation An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

, agricultural expansion and

chemical pollution A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wit ...

. These threats are likely to act locally on breeding sites. Droughts may cause additional stresses for this species.

Diet

The species diet is chiefly insects.

Conservation actions

There are many important questions that are still unanswered; however, attention must be paid to the effects water quality changes cause to the species. Less urban development, alien invasive vegetation and chemical pollution will help the frog population thrive but may not reverse the decreasing trend of this population.

References

Sources

* Bergmann, Travis; Zimkus, Breda; Gale Rosen, Daniel. 2012. ''Afrixalus knysnae''. African Amphibians Lifedesk * {{Taxonbar, from=Q1943010 Afrixalus Endemic amphibians of South Africa Taxonomy articles created by Polbot Amphibians described in 1954