AMPHIBIAWEB
Cacosternum boettgeri
Boettger's dainty frog
family: Pyxicephalidae
subfamily: Cacosterninae

© 2011 Martin Pickersgill (1 of 3)

  hear Fonozoo call

Conservation Status (definitions)
IUCN (Red List) Status Least Concern (LC)
CITES
Other International Status None
National Status None
Regional Status None

Country distribution from AmphibiaWeb's database: Botswana, Ethiopia, Kenya, Lesotho, Mozambique, Namibia, Somalia, South Africa, Swaziland, Tanzania, United Republic of, Zambia

 

View distribution map using BerkeleyMapper.

   

From the Encyclopedia of Life account:

Distribution

Cacosternum boettgeri is a very abundant and widespread species, occurring in most suitable habitat throughout its range at both high and low elevations. This frog inhabits South Africa, Lesotho, Swaziland, the savanna regions of Namibia, eastern Botswana, southern Zambia and the Zimbabwe plateau. The range of C. boettgeri may have increased in the last century due to human activity, particularly where bush and reeds have been cleared and grass has been introduced (Van Dijk 1971b) along with domestic stock (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Taxonomic Notes

This form consists of many cryptic species. Channing et al. (2005) removed Kenyan and Tanzanian population from this species, under the name Cacosternum plimptoni. Ethiopian populations should also also be separated as a distinct species (Scott and Zimkus, unpublished).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Morphology

The following is the original description from Boulenger (1882):

Head moderate; tympanum hidden. Third finger scarcely more than once and a half the length of second: tips of fingers and toes not dilated: two metatarsal tubercles. The hind limb being carried forwards along the body, the tibio-tarsal articulation marks the shoulder. Skin perfectly smooth: a curved fold from the eye to the shoulder. Olive above: a light line from below the eye to the shoulder; in some specimens, a light vertebral line and a broad light stripe from the scapular region to tho groin; transversely dilated dark spots on the legs: belly generally with round black spots; inferior surface of limbs with dark vermiculalions. Male with a large external subgular vocal sac. From snout to vent 19 millim.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Habitat and Ecology

C. boettgeri inhabits a wide variety of vegetation types in the Nama Karoo, Succulent Karoo, Savanna, Grassland, Fynbos and Thicket biomes, but is usually absent from forest, although it is sometimes found in forest clearings. Within these biomes, it favours open areas with short vegetation and is especially abundant in grassy areas. This species can tolerate dry habitats, but also occurs in high rainfall areas (Van Dijk 1977). In the Kalahari, C. boettgeri occurs naturally only in pans or along river courses, but can also be found in artificially created water bodies. The species breeds in almost any small, temporary water body, such as pools in inundated grasslands, culverts and other rainfilled depressions.


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Associations

C. boettgeri is known to feed on termites (Passmore and Carruthers 1995) but probably takes any small insect. In common with its congeners, it is probably a major predator of mosquitoes (Wager 1986). The Yellowbilled Egret Egretta intermedia, Spotted Skaapsteker Psammophylax rhombeatus (Channing 2001) and Giant Bullfrog Pyxicephalus adspersus (W.R. Branch pers. comm.) are known to prey on this frog (Text from Minter et al. 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Activity and Special Behaviors

During the dry season, C. boettgeri aestivates in mudbanks, mudcracks, burrows of other animals, disused termitaria and under stones (Text from Minter et al. 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Metamorphosis

Clutches of c.250 eggs are attached to vegetation below the surface of the water (Channing 2001). The tadpoles usually hatch two days later, and metamorphosis is completed within approximately two weeks (Pienaar et al. 1976; Wager 1986; text from Minter et al. 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Reproduction

This species appears to have an extended breeding season. During the rainy season, males usually start calling in the late afternoon and call incessantly after dark, continuing until around midnight. Large choruses are common.

Call bouts are usually initiated by the same individual in the group (Channing 2001). Males normally call from concealed positions under vegetation or other cover, at water level, but have also been observed calling from totally exposed positions. A short territorial call is sometimes uttered by individual males prior to their regular advertisement call (Text from Minter et al. 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Threats

C. boettgeri is known from various nature reserves and protected areas throughout its range and is not threatened (Text from Minter et al. 2004, © SI/MAB Biodiversity Program).


Author: Scott, E.
License: http://creativecommons.org/licenses/by-nc-sa/3.0/