AMPHIBIAWEB
Amnirana darlingi
Darling's white-lipped frog
family: Ranidae

Country distribution from AmphibiaWeb's database: Angola, Congo, the Democratic Republic of the, Malawi, Mozambique, Zambia, Zimbabwe

View distribution map using BerkeleyMapper.


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

   

From the Encyclopedia of Life account:

Summary

Hylarana darlingi inhabits a wide geographic range in Southern Africa, and a gamut of habitat types spanning dry forests, moist forests, flooded grassland and savanna; moreover, the breeding system is adapted to both lotic (still water) and lentic (moving water) systems. The reproductive style features ova-deposition in freshwater, leading to a swimming benthic tadpole phase. While moderately abundant in population, the species is experiencing threats of habitat loss and habitat fragmentation due to the burgeoning human population and concomitant agricultural land conversion and charcoal production.


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Distribution

The native range of H. darlingi extends from eastern Angola, through the Caprivi Strip of Namibia to extreme northern Botswana, extreme southeastern Democratic Republic of Congo, a considerable amount of Zambia (excepting the northeast), northern and eastern Zimbabwe, southern Malawi, and west-central Mozambique (Poynton & Channing, 2004). This anuran can be found in all of the following ecoregions: Angolan Mopane woodlands; Central Zambezian mopane woodlands (World Wildlife Fund & Hogan, 2007); Southern miombo woodlands; Zambezian and mopane woodlands; Zambezian baikiaea woodlands; Angolan montane forest-grassland mosaic.


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Habitat and Ecology

H. darlingi is a terrestrial anuran found on open savannahs, flooded grasslands, savannah woodland, and forest, occurring chiefly in upland areas. These habitats span varied realms from subtropical or tropical dry forests and moist lowland forests. moist savanna, subtropical or tropical moist shrubland, subtropical or tropical seasonally wet or flooded lowland grassland, riverine, swamp, inland lakes and marshland.There is limited information on its adaptability to secondary habitats. Its breeding occurs via a tadpole stage swimming in lentic or lotic waters in quasi-permanent to permanent waterbodies, including river side-channels, lakes, small rivers, ponds, flooded grasslands and swamps. (Poynton & Channing, 2004; World Wildlife Fund & Hogan, 2007).


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Associations

Some of the dominant trees in the portions of the range of H. darlingi are miombo mainstays, especially Brachystegia floribunda, B. glaberrima, B. taxifolia, B. wangermeeana, Marquesia macroura, Julbernadia globiflora, J. paniculata, and Isoberlinia angolensis; in fact, the Central Zambezian Miombo woodlands portion of the H darlingi range is the centre of Brachystegia endemism. (World Wildlife Fund & Hogan, 2007)

Within the range of H. darlingi, rates of faunal endemism vary greatly among taxonomic groups. For example, Mammal endemism within the Central Zambezian Miombo woodlands portion of the range, is restricted to four species of rodents, namely Monard’s dormouse (Graphiurus monardi), Rosevear's striped grass mouse (Lemniscomys roseveari), and two white-toothed shrews, Crocidura ansellorum (CR) and C. zimmeri (VU), with the last two being strict ecoregion endemics. D'Anchieta's fruit bat (Plerotes anchietae, DD), is also found in the range. (World Wildlife Fund & Hogan, 2007)

A number of larger mammals are present in the wetter parts of the range of H. darlingi, especially in the wooded margins or open areas of the floodplains and swamps. Lechwes (Kobus leche), puku (K. vardoni), tsessebe (Damaliscus lunatus), oribi (Ourebia ourebi), blue wildebeest (Connochaetes gnou) and sitatunga (Tragelaphus spekii), are antelope that prefer seasonally flooded or marshy habitat, and sometimes open grasslands here. Waterbuck (K. ellipsiprymnus), bushbuck (Tragelaphus scriptus), and blue duiker (Cephalophus monticola) are mostly found in more wooded areas close to permanent water. (World Wildlife Fund & Hogan, 2007)

Example amphibian species within the range of H. darlingi is the Shaba Province Toad (Amietophrynus fuliginatus), which occurs in Upemba National Park in the Democratic Republic of Congo and in portions of the Kafue National Park in Zambia, as well as in other locations. There are numerous other amphibians in the ecoregion, including the African clawed toad (Xenopus laevis), African ornate frog (Hildebrandtia ornata), African Peters frog (Hoplobatrachus occipitalis), African split-skin toad (Schismaderma carens), Angola forest treefrog (Leptopelis cynnamomeus), and Banded banana frog (Afrixalus fulvovittatus). The Nile crocodile (Crocodylus niloticus) and the African sharp-nosed crocodile (C. cataphractus) is also found in portions of the range as H. darlingi. (World Wildlife Fund & Hogan, 2007)


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Population Biology

In 2004 the IUCN asserted that H. darlingi was relatively common throughout much of its range (Poynton & Channing, 2004).


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Reproduction

Mercurio et al. (2009) have classified H. darlingi as a “generalist” breeder, meaning that breeding can be carried out in natural or perturbed environments. H. darlingi is categorized by Mercurio et al. (2009) as a category 1 breeding species, following the breeding classifications of Haddad & Prado (2005); category 1 breeders are characterized by the tadpoles being an intermediary organism. The adult female deposits eggs in lentic or lotic waters, breeding in stagnant waters with off channel or in channel still pools, where the mainstem itself is characterized by low velocity flow. The tadpole stage is a benthic organism.


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Tadpole morphology

The following description of the tadpole stage is based upon Gosner Stage 36 and Stage 37 specimens, with DNA validation for a Stage 37 individual. In lateral view the body shape is ovoid, with body length approximately equal to body height. Snout presents as oblique, and the mouth is directed ventrally. The bulging eyes are of moderate size, and they are directed laterally. The pineal ocellus is present at the level of the anterior border of the eye. The minute nares are rounded directed somewhat more laterally than anterolaterally. The spiracle is tubular and moderately large in size, situated closer to the tail than snout. The oval vent tube is of moderately large size, and the tail fins and tail musculature are classified as moderate. The tail tip exhibits a somewhat rounded appearance. Jaw sheets are capsulated and rounded. In vivo, the exterior color is a pale orange with dark spots, and the iris is a golden orange. Body length is approximately 24 millimeters (Conradie, Tweddle, Makinen & Bills, 2012).


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

IUCN Red List Category and Justification of Conservation Status

The IUCN lists H. darlingi in the classification of Least Concern in view of the species broad distribution, tolerance of a gamut of habitat types, presumed large population, and since the total population is unlikely to be declining fast enough to qualify for listing in a more threatened category (Poynton & Channing, 2004).


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Trends

The population of H. darlingi as of 2004 was judged to be stable. However, increasing threats that are producing widespread habitat destruction and habitat fragmentation suggest that the species is likely to be in a state of decline as of 2012 (Poynton & Channing, 2004).


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/

Threats

In 2004 the IUCN asserted that H. darlingi was at that time "unlikely to be significantly threatened" (Poynton & Channing, 2004) However, conditions as of 2012 reveal significant pressures deriving from the expanding human population of the region, particularly manifested by conversion of natural habitat to agriculture, extraction of river water for human consumption, and widespread slash-and-burn practises. While the population fo H. darlingi may be secure for the present, the threat accretion trends place a significant pressure upon the habitat itself, as well as the fragmentation of habitat.


Author: Hogan, C.Michael
License: http://creativecommons.org/licenses/by-nc-sa/3.0/