| Knysna Banana Frog | |
|---|---|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Amphibia |
| Order: | Anura |
| Family: | Hyperoliidae |
| Genus: | Afrixalus |
| Species: | A. knysnae |
| Binomial name | |
| Afrixalus knysnae (Loveridge, 1954) |
|
The Knysna Banana Frog (Afrixalus knysnae) is a species of frog in the Hyperoliidae family. It is endemic to South Africa.
Contents |
Its natural habitats are temperate forests, Mediterranean-type shrubby vegetation, freshwater marshes, intermittent freshwater marches, arable land, water storage areas, and ponds. It is threatened by habitat loss.
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).
Knysna Banana Frogs are Terrestrial; Freshwater amphibians. 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.
List of Habitats 1 Forest 1.4 Forest - Temperate 3 Shrubland 3.8 Shrubland - Mediterranean-type Shrubby Vegetation 5 Wetlands (inland) 5.7 Wetlands (inland) - Permanent Freshwater Marshes/Pools (under 8ha) 5.8 Wetlands (inland) - Seasonal/Intermittent Freshwater Marshes/Pools (under 8ha) 14 Artificial/Terrestrial 14.1 Artificial/Terrestrial - Arable Land 15 Artificial/Aquatic & Marine 15.1 Artificial/Aquatic - Water Storage Areas (over 8ha) 15.2 Artificial/Aquatic - Ponds (below 8ha)
The Knysna Banana Frog is creamy and yellow color with lateral brown stripes. The females have a smooth texture.
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 things have been the sole reason of the decline and therefore affecting 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. The change in water quality is most likely due to urbanization.
The main threat is habitat loss due to urban and recreational development, afforestation, invasive vegetation, agricultural expansion and chemical pollution. These threats are likely to act locally on breeding sites. Drought may cause additional stresses for this species.
Mostly insects.
Among frogs this species is the most threatened and needs the most help. There are many important questions that are still unanswered; however the most important things we need to concentrate on now is what effects take place on the frogs when the water quality changes. Less urban development, alien invasive vegetation, and chemical pollution will help the frog population thrive but it will not totally stop the extermination of this population.