Bradypodion
Encyclopedia
Bradypodion is one of six genera
of chameleon
s within the "true" or "typical" chameleons (subfamily Chamaeleoninae
). They are native to southern Africa
, and are sometimes collectively called South African dwarf chameleons. Some other small chameleons from eastern and central Africa are occasionally placed herein, but this is probably in error and not followed here. See also "Systematics" below and Kinyongia
and Nadzikambia
.
characters, but for some time the genus was used as a wastebin taxon
for smaller chameleons from sub-Saharan Africa
with a plesiomorphic hemipenis
. Alternatively, many of the present species were reduced to subspecies status. This has since been refuted, but several more species seem recognizable judging from morphological and mitochondrial 16S rRNA and NADH dehydrogenase
subunit
2 sequence
data.
The phylogeny and biogeography
of this group is quite consistently resolved. The Cape Dwarf Chameleon
and the Knysa Dwarf Chameleon (and possibly one new species close to it) are basal lineages with unclear relationships; they seem a bit closer to each other than to any other species but altogether are quite distant. They occur in isolated ranges in coastal Western Cape
and western Eastern Cape
provinces. Inhabiting a wide range of habitat
s, they are (for the genus) large, and have brilliant, predominantly green coloration and a long tail - just as in many Chamaeleo
. These characters are plesiomorphic, retained from the genus' ancestor.
The remaining species form a well-supported clade
, which in turn can be divided into smaller groups. One consists of forms that radiated on the seawards slopes of the Drakensberg mountains: the southern Drakensberg Dwarf Chameleon, the northern Transvaal Dwarf Chameleon
, and what appears to be undescribed species from the Ngome Forest
on the SE slopes. These are also plesiomorphic in habitus and habits.
Another group of taxa occurs from easternmost Eastern Cape to central KwaZulu-Natal
provinces, between Gilboa Forest and the Tugela River
. These inhabit a wide range of habitat and contain the plesiomorphic Natal Midlands Dwarf Chameleon
from the namesake region, the small Black-headed Dwarf Chameleon which inhabits fynbos
and other low forest on slopes of mainly coastal W KwaZulu-Natal, and another probable new species from the Gilboa Forest area. These appear to be a quite recent radiation from a single ancestor and the group requires more research as regards species limits, and geographical demilitation from the Drakensberg Dwarf Chameleon.
There are several largish but short-tailed and cryptic
taxa which inhabit more arid
habitat
such as karoo
. The Karroo
and Southern Dwarf Chameleons between which there seems to be considerable gene flow
range from Northern Cape
to coastal Eastern Cape provinces. The small and nearly extinct Smith's Dwarf Chameleon is close to these; it occurs on the escarpment
inland from Jeffreys Bay
. Less closely related is the Robertson Dwarf Chameleon
, another aridland species which is found in Western Cape province inland from the range of the Cape Dwarf Chameleon and may be a cryptic species complex
, and an undescribed population from the Swartberg mountains. The last species with aridland apomorphies, the Namaqua Dwarf Chameleon, is quite distant to the others; it occurs in coastal regions from north of the Cape species through Namaqualand
. This is probably still a part of a single radiation which brought about all the aridland taxa, and eventually Smith's Dwarf Chameleon.
The remaining species are all small inhabitants of forested slopes and fynbos, like the Black-headed and Smith's Dwarf Chameleons. However, as already indicated by the distinctness of these two, their morphology seems to be a convergent
adaptation. The Kentani and Transkei Dwarf Chameleon
s from the E coasts of Eastern Cape may or may not be each other's closest relatives. Setaro's Dwarf Chameleon
from northeastern coastal KwaZulu-Natal is not close to these. The Zululand Dwarf Chameleon from western uThungulu apparently consists of 2 or more species, one that may be closer to the preceding, and one that might be an early offshoot of the ancestral Drakensberg stock, and which are distinguishable by morphological and mtDNA characteristics.
In conclusion, of the 3 basic morphotypes found in this genus, one (bright, long-tailed, large) is plesiomorphic, another (large, short-tailed, drab) apparently only evolved once, and the third (the small slope-inhabiting forms) are convergent in morphology. The ancestors of Bradypodion thus were mid-sized chameleons with vivid color, which settled the Cape region from roughly north-northwestwards. Due to climate change
with fluctuating aridity, the basal lineages inhabiting humid fynbos in the SW became isolated from each other and from the animals living approximately in the border region between Northern and Eastern Cape and Free State
, and Lesotho
. The aridland habitat fluctuates in extent during climate shifts, and mountaineous habitat becomes fragmented or consolidates accordingly. Consequently, the Drakensberg, the thamnobates-melanocephalum, and the aridland group, as well as several coastal lineages diverged and evolved to their present-day ranges and diversity.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of chameleon
Chameleon
Chameleons are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot-like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, the possession by many of a...
s within the "true" or "typical" chameleons (subfamily Chamaeleoninae
Chamaeleoninae
Chamaeleoninae is the nominotypical subfamily of chameleons -Classification:There are eight currently recognised genera in the subfamily:*Genus Archaius*Genus Bradypodion*Genus Calumma*Genus Chamaeleo...
). They are native to southern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, and are sometimes collectively called South African dwarf chameleons. Some other small chameleons from eastern and central Africa are occasionally placed herein, but this is probably in error and not followed here. See also "Systematics" below and Kinyongia
Kinyongia
Kinyongia is a chameleon genus that recently was established for several plesiomorphic species found in forest and woodland in Kenya, Tanzania, Uganda, Rwanda and far eastern DR Congo. All except K. adolfifriderici and K. tavetana are restricted to highlands and many have very small distributions....
and Nadzikambia
Nadzikambia
There are currently two species in the recently established genus Nadzikambia . They are plesiomorphic, small chameleons from the Ruo Gorge forest on Mount Mulanje in Malawi and Mount Mabu in Mozambique....
.
Alphabetic species list
- Swartberg Dwarf Chameleon, Bradypodion atromontanumBradypodion atromontanumThe Swartberg Dwarf Chameleon, is a chameleon in the genus Bradypodion. It is native to southern Africa....
- uMlalazi Dwarf Chameleon, Bradypodion caeruleogulaBradypodion caeruleogulaThe uMlalazi Dwarf Chameleon is endemic to KwaZulu-Natal, South Africa. It is found in Dhlinza, Entumeni and Ongoye Forests.-References:...
- Transkei Dwarf ChameleonTranskei Dwarf ChameleonThe Transkei Dwarf Chameleon is a chameleon in the genus Bradypodion. It is native to southern Africa. It is also known as the Pondo Dwarf Chameleon.-External links:*...
, Bradypodion caffrum - Knysna Dwarf ChameleonKnysna Dwarf ChameleonThe Knysna Dwarf Chameleon is a species of dwarf chameleon in the Bradypodion genus of chameleons that are endemic to South Africa. It is a forest dweller, found only in a limited range in the afromontane forests near Knysna, South Africa, and in certain other areas...
, Bradypodion damaranum - Drakensberg Dwarf Chameleon, Bradypodion dracomontanumBradypodion dracomontanumThe Drakensberg Dwarf Chameleon occurs in the Drakensberg, South Africa. It may be composed of two species and a common name for the bright green individuals in the southern part of the distribution has been proposed as the Emerald Dwarf Chameleon.-Bibliography:* Tolley, K. and Burger, M. 2007....
- Robertson Dwarf ChameleonRobertson Dwarf ChameleonThe Robertson Dwarf Chameleon is a chameleon in the genus Bradypodion. It is endemic to South Africa, found only in a limited range in the south-central region of South Africa's Western Cape province. It prefers the fynbos vegetation, unlike some other species of dwarf chameleon that are forest...
, Bradypodion gutturale (may be several species) - Karoo Dwarf ChameleonKaroo Dwarf ChameleonThe Karoo Dwarf Chameleon is a chameleon native to South Africa. It is about 14 cm long, mostly colored grey and brown, sometimes olive...
, Bradypodion karrooicum - Kentani Dwarf Chameleon, Bradypodion kentanicumBradypodion kentanicumThe Kentani Dwarf Chamaeleon occurs in coastal area of the Eastern Cape, South Africa.-References:* Tolley, K. and Burger, M. 2007. Chameleons of Southern Africa. ISBN 978-1-77007-375-3.-External links:*...
- Black-headed Dwarf Chameleon, Bradypodion melanocephalum
- Zululand Dwarf Chameleon, Bradypodion nemorale (probably several species)
- Ngome Dwarf Chameleon Bradypodion ngomeense
- Namaqua Dwarf Chameleon, Bradypodion occidentaleBradypodion occidentaleBradypodion occidentale is known as the Namaqua Dwarf Chameleon or the Western Dwarf Chameleon. It occurs in the western regions of South Africa.-References:...
- Cape Dwarf ChameleonCape Dwarf ChameleonThe Cape Dwarf Chameleon , is a chameleon native to the South African province of the Western Cape where it is restricted to the region around Cape Town. As with most chameleons, its tongue is twice the length of its body and it can be shot out of its mouth using a special muscle in the jaw...
, Bradypodion pumilum - Setaro's Dwarf ChameleonSetaro's Dwarf ChameleonThe Setaro's Dwarf Chameleon is a species of lizard in the Chamaeleonidae family. With a length of about 10 cm, it is one of the smallest of all the Dwarf Chameleons...
, Bradypodion setaroi - Smith's Dwarf Chameleon, Bradypodion taeniabronchum
- Natal Midlands Dwarf ChameleonNatal Midlands Dwarf ChameleonThe Natal Midlands Dwarf Chameleon , also known under the longer common name of KwaZulu-Natal Midlands Dwarf Chameleon, is a chameleon native to woodland habitat in the Midlands area of the South African province of KwaZulu-Natal.Its length is 19 cm . They have bulbous scales of varying colors...
, Bradypodion thamnobates - Transvaal Dwarf ChameleonTransvaal Dwarf ChameleonThe Transvaal Dwarf Chameleon is a chameleon in the genus Bradypodion. It is native to South Africa where it is found in forested areas of Mpumalanga and Limpopo provinces. It is also known as the Wolkberg Dwarf Chameleon.A related species is found in Ngome Forest, KwaZulu-Natal known as the Ngome...
, Bradypodion transvaalense - Southern Dwarf Chameleon, Bradypodion ventraleBradypodion ventraleThe Southern Dwarf Chameleon occurs in the Eastern Cape, South Africa. It is also known as the Eastern Cape Dwarf Chameleon. It is a relatively large species of Dwarf Chameleon, reaching lengths of 14 cm. It has a very prominent casque on the back of its head and a long, beard-like throat crest...
Undescribed Species
- Bradypodion sp. (barbatulum)
- Bradypodion sp. (Baviaans)
- Emerald Dwarf Chameleon, Bradypodion sp. (Emerald)
- Bradypodion sp. (Groendal)
- Bradypodion sp. (Grootvadersbosch)
- Bradypodion sp. (Jagersbos)
Systematics
Delimitation of Bradypodion has been controversial for some time. Most species seem readily distinguishable by morphologicalMorphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characters, but for some time the genus was used as a wastebin taxon
Wastebin taxon
Wastebasket taxon is a term used in some taxonomic circles to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined by their lack of one or more distinct character states or by their not belonging to one or more other taxa...
for smaller chameleons from sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...
with a plesiomorphic hemipenis
Hemipenis
A hemipenis is one of a pair of intromittent organs of male squamates .Hemipenes are usually held inverted, within the body, and are everted for reproduction via erectile tissue, much like that in the human penis. Only one is used at a time, and some evidence indicates males alternate use between...
. Alternatively, many of the present species were reduced to subspecies status. This has since been refuted, but several more species seem recognizable judging from morphological and mitochondrial 16S rRNA and NADH dehydrogenase
NADH dehydrogenase
NADH dehydrogenase is an enzyme located in the inner mitochondrial membrane that catalyzes the transfer of electrons from NADH to coenzyme Q...
subunit
Protein subunit
In structural biology, a protein subunit or subunit protein is a single protein molecule that assembles with other protein molecules to form a protein complex: a multimeric or oligomeric protein. Many naturally occurring proteins and enzymes are multimeric...
2 sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
data.
The phylogeny and biogeography
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
of this group is quite consistently resolved. The Cape Dwarf Chameleon
Cape Dwarf Chameleon
The Cape Dwarf Chameleon , is a chameleon native to the South African province of the Western Cape where it is restricted to the region around Cape Town. As with most chameleons, its tongue is twice the length of its body and it can be shot out of its mouth using a special muscle in the jaw...
and the Knysa Dwarf Chameleon (and possibly one new species close to it) are basal lineages with unclear relationships; they seem a bit closer to each other than to any other species but altogether are quite distant. They occur in isolated ranges in coastal Western Cape
Western Cape
The Western Cape is a province in the south west of South Africa. The capital is Cape Town. Prior to 1994, the region that now forms the Western Cape was part of the much larger Cape Province...
and western Eastern Cape
Eastern Cape
The Eastern Cape is a province of South Africa. Its capital is Bhisho, but its two largest cities are Port Elizabeth and East London. It was formed in 1994 out of the "independent" Xhosa homelands of Transkei and Ciskei, together with the eastern portion of the Cape Province...
provinces. Inhabiting a wide range of habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s, they are (for the genus) large, and have brilliant, predominantly green coloration and a long tail - just as in many Chamaeleo
Chamaeleo
Chamaeleo is a genus of chameleons found primarily in the mainland of sub-saharan Africa, but a few species are also present in northern Africa, southern Europe and southern Asia east to India and Sri Lanka. They are slow moving with independently movable eyes, the ability to change skin...
. These characters are plesiomorphic, retained from the genus' ancestor.
The remaining species form a well-supported clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
, which in turn can be divided into smaller groups. One consists of forms that radiated on the seawards slopes of the Drakensberg mountains: the southern Drakensberg Dwarf Chameleon, the northern Transvaal Dwarf Chameleon
Transvaal Dwarf Chameleon
The Transvaal Dwarf Chameleon is a chameleon in the genus Bradypodion. It is native to South Africa where it is found in forested areas of Mpumalanga and Limpopo provinces. It is also known as the Wolkberg Dwarf Chameleon.A related species is found in Ngome Forest, KwaZulu-Natal known as the Ngome...
, and what appears to be undescribed species from the Ngome Forest
Ngome Forest
Ngome Forest is situated to the east of Vryheid, KwaZulu-Natal, South Africa.This is a unique forest, being transitional between Mistbelt Forest and Coastal Scarp Forest...
on the SE slopes. These are also plesiomorphic in habitus and habits.
Another group of taxa occurs from easternmost Eastern Cape to central KwaZulu-Natal
KwaZulu-Natal
KwaZulu-Natal is a province of South Africa. Prior to 1994, the territory now known as KwaZulu-Natal was made up of the province of Natal and the homeland of KwaZulu....
provinces, between Gilboa Forest and the Tugela River
Tugela River
The Tugela River is the largest river in KwaZulu-Natal Province, South Africa. The river originates in the Drakensberg Mountains, Mont-aux-Sources, and plunges 947 metres down the Tugela Falls...
. These inhabit a wide range of habitat and contain the plesiomorphic Natal Midlands Dwarf Chameleon
Natal Midlands Dwarf Chameleon
The Natal Midlands Dwarf Chameleon , also known under the longer common name of KwaZulu-Natal Midlands Dwarf Chameleon, is a chameleon native to woodland habitat in the Midlands area of the South African province of KwaZulu-Natal.Its length is 19 cm . They have bulbous scales of varying colors...
from the namesake region, the small Black-headed Dwarf Chameleon which inhabits fynbos
Fynbos
Fynbos is the natural shrubland or heathland vegetation occurring in a small belt of the Western Cape of South Africa, mainly in winter rainfall coastal and mountainous areas with a Mediterranean climate...
and other low forest on slopes of mainly coastal W KwaZulu-Natal, and another probable new species from the Gilboa Forest area. These appear to be a quite recent radiation from a single ancestor and the group requires more research as regards species limits, and geographical demilitation from the Drakensberg Dwarf Chameleon.
There are several largish but short-tailed and cryptic
Crypsis
In ecology, crypsis is the ability of an organism to avoid observation or detection by other organisms. It may be either a predation strategy or an antipredator adaptation, and methods include camouflage, nocturnality, subterranean lifestyle, transparency, and mimicry...
taxa which inhabit more arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...
habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
such as karoo
Karoo
The Karoo is a semi-desert region of South Africa. It has two main sub-regions - the Great Karoo in the north and the Little Karoo in the south. The 'High' Karoo is one of the distinct physiographic provinces of the larger South African Platform division.-Great Karoo:The Great Karoo has an area of...
. The Karroo
Karoo Dwarf Chameleon
The Karoo Dwarf Chameleon is a chameleon native to South Africa. It is about 14 cm long, mostly colored grey and brown, sometimes olive...
and Southern Dwarf Chameleons between which there seems to be considerable gene flow
Gene flow
In population genetics, gene flow is the transfer of alleles of genes from one population to another.Migration into or out of a population may be responsible for a marked change in allele frequencies...
range from Northern Cape
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of an international park shared with Botswana...
to coastal Eastern Cape provinces. The small and nearly extinct Smith's Dwarf Chameleon is close to these; it occurs on the escarpment
Escarpment
An escarpment is a steep slope or long cliff that occurs from erosion or faulting and separates two relatively level areas of differing elevations.-Description and variants:...
inland from Jeffreys Bay
Jeffreys Bay
Jeffreys Bay is a town located in the Eastern Cape province of South Africa. The town is situated just off the N2 Highway, about an hour's drive southwest of Port Elizabeth.- History :...
. Less closely related is the Robertson Dwarf Chameleon
Robertson Dwarf Chameleon
The Robertson Dwarf Chameleon is a chameleon in the genus Bradypodion. It is endemic to South Africa, found only in a limited range in the south-central region of South Africa's Western Cape province. It prefers the fynbos vegetation, unlike some other species of dwarf chameleon that are forest...
, another aridland species which is found in Western Cape province inland from the range of the Cape Dwarf Chameleon and may be a cryptic species complex
Cryptic species complex
In biology, a cryptic species complex is a group of species which satisfy the biological definition of species—that is, they are reproductively isolated from each other—but whose morphology is very similar ....
, and an undescribed population from the Swartberg mountains. The last species with aridland apomorphies, the Namaqua Dwarf Chameleon, is quite distant to the others; it occurs in coastal regions from north of the Cape species through Namaqualand
Namaqualand
Namaqualand is an arid region of Namibia and South Africa, extending along the west coast over and covering a total area of 170,000 square miles/440,000 km². It is divided by the lower course of the Orange River into two portions - Little Namaqualand to the south and Great Namaqualand to the...
. This is probably still a part of a single radiation which brought about all the aridland taxa, and eventually Smith's Dwarf Chameleon.
The remaining species are all small inhabitants of forested slopes and fynbos, like the Black-headed and Smith's Dwarf Chameleons. However, as already indicated by the distinctness of these two, their morphology seems to be a convergent
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
adaptation. The Kentani and Transkei Dwarf Chameleon
Transkei Dwarf Chameleon
The Transkei Dwarf Chameleon is a chameleon in the genus Bradypodion. It is native to southern Africa. It is also known as the Pondo Dwarf Chameleon.-External links:*...
s from the E coasts of Eastern Cape may or may not be each other's closest relatives. Setaro's Dwarf Chameleon
Setaro's Dwarf Chameleon
The Setaro's Dwarf Chameleon is a species of lizard in the Chamaeleonidae family. With a length of about 10 cm, it is one of the smallest of all the Dwarf Chameleons...
from northeastern coastal KwaZulu-Natal is not close to these. The Zululand Dwarf Chameleon from western uThungulu apparently consists of 2 or more species, one that may be closer to the preceding, and one that might be an early offshoot of the ancestral Drakensberg stock, and which are distinguishable by morphological and mtDNA characteristics.
In conclusion, of the 3 basic morphotypes found in this genus, one (bright, long-tailed, large) is plesiomorphic, another (large, short-tailed, drab) apparently only evolved once, and the third (the small slope-inhabiting forms) are convergent in morphology. The ancestors of Bradypodion thus were mid-sized chameleons with vivid color, which settled the Cape region from roughly north-northwestwards. Due to climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
with fluctuating aridity, the basal lineages inhabiting humid fynbos in the SW became isolated from each other and from the animals living approximately in the border region between Northern and Eastern Cape and Free State
Free State
The Free State is a province of South Africa. Its capital is Bloemfontein, which is also South Africa's judicial capital. Its historical origins lie in the Orange Free State Boer republic and later Orange Free State Province. The current borders of the province date from 1994 when the Bantustans...
, and Lesotho
Lesotho
Lesotho , officially the Kingdom of Lesotho, is a landlocked country and enclave, surrounded by the Republic of South Africa. It is just over in size with a population of approximately 2,067,000. Its capital and largest city is Maseru. Lesotho is a member of the Commonwealth of Nations. The name...
. The aridland habitat fluctuates in extent during climate shifts, and mountaineous habitat becomes fragmented or consolidates accordingly. Consequently, the Drakensberg, the thamnobates-melanocephalum, and the aridland group, as well as several coastal lineages diverged and evolved to their present-day ranges and diversity.