Fossil Chameleons
Due to their relatively small size, chameleon fossils are very scarce in paleontological localities and literature.
The estimated split of chameleons from the agamids is around 123 Mya, the question when real chameleons formed is under permanent discussions and different approaches vary from around 100 Mya through 605/60 Mya to 23 Mya...
Here, there is a list of the known chameleon fossil forms with few comments.
Paleocene (66-56Mya)
Anquingosaurus brevicephalus
Hou, 1976
reported from the early Paleocene of Wang-Hu-Dun Series, Qian-Shan district, Anhui, China
there is no evidence that it is a chameleon
Miocene (23-5,3Mya)
Chamaeleo caroliquarti
Moody and Roček, 1980
- reported from: Merkur Nord, Czech Republic; Wintershof West, Germany; Petersbuch 28, 36, and 36 II, Germany; Erkertshofen 1, Germany; Dolnice, Czech Republic; Gisseltshausen 1b, Germany; Griesbeckerzell 1b, Germany; Untereichen-Altenstadt 565 m, Germany; Petersbuch 39, Germany; Laimering 2a and 3, Germany: Wannenwaldtobel 2, Germany
- Čerňanský considers Chamaeleo caroliquarti a nomen dubium because the holotype dentary cannot be differentiated from recent representativesof the genera Chamaeleo, Calumma and Furcifer
Chamaeleo bavaricus
Schleich, 1983
reported from: Unterempfenbach, Aresing (MN5), Arth 1a, Sandelzhausen C3/D1, and Laimering 2a, all Germany
Chamaeleo pfeili
Schleich, 1984
- reported from Rauscheröd and Langenau, both Germany
- recently degraded as nomen dubium by Čerňanský due to the impossibility to allocate it to the genus based on any feature
Chamaeleo sulcodentatus
Schleich, 1994
reported from Massendorf, Göttschlag 1b, and Laimering 3, all Germany and Rümikon, Switzerland
Chamaeleo simplex
Schleich 1984
reported from MN5, Germany
Chamaeleo andrusovi
Čerňanský 2010
reported from Dolnice, Czech Republic
part of the material originally referred to Ch. caroliquarti at its description
recently tentatively reported from Aliveri (Evia Island), Greece
Chamaeleo intermedius
Hillenius, 1978
described from Fort Ternan, Kenya
a cast in calcite: head and anterior part of the body
attributed to the genus Chamaeleo seems justified
Calumma benovskyi
Čerňanský, Herrel, Kibii, Anderson, Boistel & Lehmann 2020
the fossil material of
Calumma benovskyiwas discovered by Alan Walker in the Miocene sediments of the Hiwegi Formation of Rusinga Island, Kenya
the type specimen (KNM-RU 18340), a complete skulland the first three neck vertebrae, was then preliminarily described by Rieppel, Walker and Odhiambo on the basis of a cast and photographs in 1992
30 years later the skull was subjected to X-ray microcomputed tomography
the species is named after Maurice Benyovszky, a military officer and traveler born in Vrbové, Slovakia who made several travels to Madagascar
Rhampholeon sp.
reported from Rusinga Island, Kenya
Miocene European chamaeleons
reported from many localities across Czech Republic, Germany and Switzerland
oldest 20-21 Mya from the mine Merkur-North in Czech Republic
most specimens consist of incomplete maxillae, dentaries and cranial fragments
Miocene African Chameleons
reported from Kenya, mainly undescribed
frequent undescribed chameleon bone fragments reported from primate paleontological localities Koru and Songhor
Miocene Asian Chameleons
reported from Sabuncubeli, Dededağ (western Anatolia); Paşalar (northwestern Anatolia), Turkey
Pleistocene and Holocene (5,3Mya-present)
Chamaeleo chamaeleon
Linnaeus, 1789
- Ksâr'akil in Lebanon
Abu Usba Cave (Mount Carmel), Israel
Málaga, Spain
Guenfouda, Morocco
Trioceros cf. jacksonii
Boulenger, 1896
Africa: Bed 1, Olduvai Gorge, Tanzania
Pleistocene and Holocene Chameleons
Madagascar: Children's Cave (Antsirabe), Cavern Ambatohomana
Asia: Chamaeleo sp. have been reported from Israel
Africa:
Africa: Bradypodion sp. have been reported from Langebaan Fossil Bed, RSA (early Pliocene - 5.2 Mya)
Map of fossil finds of chameleons
A common belief suggested the Madagascar origin of Chameleons, floating on trees across seas to Africa. However, recent research using genetic analysis challenges this notion. A fossil skull from Kenya, belonging to a genus present only in Madagascar today, hints at an African origin. The skull, dated to about 18 million years ago, reveals intricate details through micro-CT scanning, identifying it as a new Calumma species, Calumma benovskyi.
This discovery supports the theory that chameleons potentially originated in Africa and dispersed to Madagascar aided by ancient ocean currents. The study underscores the significance of modern technologies in paleontological research. The discovery of a Calumma chameleon fossil in Kenya challenges the belief that chameleons originated in Madagascar and floated to Africa on rafts. This unique find suggests an African origin for some Malagasy lineages, emphasizing the continent's role in chameleon evolution.
During the early Miocene, Madagascar and Africa were already separated, prompting theories of ancient animal dispersal between the two landmasses. The presence of Malagasy lineage fossils in Africa, like the Aye-Aye, echoes this pattern and supports the concept of tree rafting for intercontinental migration.
Historical ocean currents favored eastward dispersal towards Madagascar, limiting chameleons' movement from the island to Africa. Post early Miocene, currents redirected westward, hindering travels back to Madagascar. This geographical dynamic influenced the biodiversity and isolation of Madagascar, allowing chameleons to diversify and flourish exclusively on the island.
The Nairobi National Museum houses this significant chameleon skull fossil, shedding light on the species' evolutionary history.
Drawing of the KNM-RU-18340 specimen (Rusinga Island, Kenya, Early Miocene) referred to Rhampholeon, in lateral (top) and dorsal (bottom) views. lABelS: d 5 dentary, f 5 frontal, EN 5 external naris, ju 5 jugal, m 5 maxilla, n 5 nasals, OR 5 orbit, p 5 parietal, PFF 5 prefrontal fontanelle, pfr 5 prefrontal, pm 5 premaxilla, pof 5 postorbitofrontal, q 5 quadrate, sang 5 surangular, sq 5 squamosal, UTF 5 upper temporal fenestra.
Amber Chameleon Mistake
Beware, the following topic appeared to be a wrong interpretation. Despite it made headlines and got extreme PR, the amber specimen does not represent any chameleon...