Six new Rhampholeon species in Tanzania

Six new Rhampholeon species in Tanzania

Neubeschreibungen Science

In the last 15 years, the number of known Rhampholeon species has doubled – not least because some species complexes “hid” numerous undescribed species. Scientists from Great Britain, Tanzania, and South Africa have now shed light on exactly such a case: the Rhampholeon uluguruensis/moyeri complex. The pygmy chameleons from this complex inhabit different habitats in the Eastern Arc Mountains, a 600 km long mountain range stretching from Kenya to Tanzania. The most striking feature of the genus Rhampholeon so far is that the described species differ only slightly in appearance, but occur in narrowly defined habitats that are usually completely isolated from each other. The authors studied pygmy chameleons from seven different locations in Tanzania. In the process, they were able to identify six new Rhampholeon species by means of genetic studies.

Rhampholeon colemani was named after the conservationist Carter Coleman. The species occurs in the Kitolomero Valley at about 1200 m a.s.l.. The valley is located in the Uzungwa Scarp Nature Reserve in the Udzungwa Mountains in the middle of Tanzania, about 350 km south-east of the capital Dodoma. What is special about this distribution area is that the already-known Rhampholeon moyeri also occurs in this reserve. It is still unclear whether the two species possibly live at different altitudes. Rhampholeon colemani grows up to 44 mm (TL) and is thus the second smallest of the Rhampholeon species described so far. The hemipenes of the males of these species could be described in detail. A characteristic feature of Rhampholeon colemani is the rostral appendage, which is at an angle of up to 59° to the snout or points slightly downwards. In all other terrestrial chameleons of the genus, the angle is much smaller, so the rostral appendage is rather straightforward.

Rhampholeon sabini was named in honour of Andy Sabin for his financial support and worldwide commitment to conservation. The species lives in Tanzania in the sub-montane rainforest of two neighbouring reserves, which are located in the north-east of the country about 250 km from the coastal city of Dar es Salaam. One of the habitats is the Nguu North Forest Reserve, the other the Kilindi Forest Reserve, both at an altitude of just over 1200 m above sea level. Rhampholeon sabini grows up to 54 mm, with the relative size of the head and tail appearing larger in relation to the rest of the body than in the other species.

Rhampholeon rubeho occurs on the mountains of the same name, the Rubeho Mountains, at about 1870 m a.s.l., located about 150 km east of the capital Dodoma. The rainforest inhabited by this species is mainly in the Mafwomero Forest Reserve. Rhampholeon rubeho grows up to 63 mm long. In addition, scientists currently count a population of earth chameleons in the Ilole Forest Reserve 50 km away, on the southern foothills of the Rubeho Mountains, as belonging to this species. However, this population has not yet been genetically studied.

Rhampholeon nicolai was named after the late Nicola Colangelo, a Tanzanian entrepreneur who promoted species conservation and sustainable resource use. Rhampholeon nicolai grows up to 60 mm long, and similar to R. sabini, the relative size of the head and tail in relation to the rest of the body appears larger than in the other species. Rhampholeon nicolai lives in the Ukaguru Mountains, just north of the Rubeho Mountains. It has been recorded in the three contiguous protected areas of Mamiwa Kisara North Forest Reserve, Mamiwa Kisara South Forest Reserve and the Ikwamba Forest Reserve at 1970 m altitude. A population of ground chameleons in nearby Mikuvi Forest is initially counted as part of the species, but its exact status has yet to be investigated.

Rhampholeon waynelotteri was given its name in honour of the murdered South African conservation activist Wayne Lotter, who was particularly active in the fight against elephant poaching. This pgymy chameleon grows up to 55 m tall. It inhabits Mount Kanga, about 120 km from the Indian Ocean coast. Mount Kanga is part of the Nguru Mountains, although the mountain is separated from the main massif by an 8 km wide lowland corridor and a river. Rhampholeon waynelotteri is described from the Kanga Forest Reserve at about 1280 m as well as de Mkingu Nature Reserve. In the latter, it occurs together with Rhampholeon acuminatus, from which it can be easily distinguished by its differently shaped rostral appendage and small appendages above the eyes. A pygmy chameleon population on Mount Nguru was initially attributed to Rhampholeon waynelotteri, but further research is pending.

Rhampholeon princeeai was named after the American artist and YouTuber Prince Ea. Rhampholeon princeeai lives at altitudes of 1870 m in the Mkingu Nature Reserve on the Nguru Mountains. Rhampholeon waynelotteri and Rhampholeon acuminatus also occur there. The species grows up to 46 mm long and has a special feature: the rostral appendage has a triangular shape when viewed from above. In addition, the species has a small depression in the inguinal region, which the other species studied so far do not have.

The already known species Rhampholeon uluguruensis was found exclusively in the Uluguru Nature Reserve and the Mkungwe Forest Reserve. Rhampholeon moyeri is found only in the Uzungwa Scarp Nature Reserve in the Udzungwa Mountains. Rhampholeon beraduccii is restricted to the Sali Forest Reserve in the Mahenge Mountains and Rhampholeon acuminatus, as anticipated, lives exclusively in the Mingu Nature Reserve in the Nguru Mountains.

Cryptic diversity in pygmy chameleons (Chamaeleonidae: Rhampholeon) of the Eastern Arc Mountains of Tanzania, with description of six new species
Michelle Menegon, John V. Lyakurwa, Simon P. Loader, Krystal A. Tolley
Acta Herpetologica 17 (2): 85-113, 2022
DOI: 10.36253/a_h-12978

Photo: Rhampholeon rubeho, from the above-mentioned publication

The Indian Chameleon in Jhalawar

The Indian Chameleon in Jhalawar

Science

Three scientists from India have recently published a survey of reptile and amphibian occurrences. The Jhalawar study area is located at the southernmost tip of the state of Rajasthan in northwest India. It is located on the edge of the Malwa Plateau, a volcanic highland. The area lies well to the southwest of the Ganges River, which is generally considered the distribution limit of the Indian Chameleon (Chamaeleo zeylanicus). The climate is divided into a long summer season and a shorter winter, which lasts from October to February. During the summer, temperatures above 45°C are common, while in winter temperatures can drop to as low as 1°C.

The three researchers were on site for about six hours each for 70 days. To search for reptiles and amphibians, they rummaged through loose soil as well as the foliage layer and visually searched for animals in parallel. 45 different species of reptiles and amphibians were found. Chamaeleo zeylanicus was documented for the first time in Rajasthan.

Herpeto-faunal diversity study: Analysis and critical observations from south-eastern Rajasthan, India
Yadav Vijay Kumar, Nama Krishnendra Singh, Sudhindran Rimal
Indian Journal of Ecology 49 (5), 2022: pp. 1581-1587
DOI: 10.55362/IJE/2022/3700

Genetics: Karyotype in the Veiled Chameleon

Genetics: Karyotype in the Veiled Chameleon

Science

It has been known for some time that the sex of the Veiled chameleon (Chamaeleo calyptratus) is genetically determined. The species has an XX/XY system. Scientists from Russia, Great Britain, Italy, and Thailand have now studied the karyotype of the species, i.e. the characteristics of the chromosomes.

The probably most original karyotype of all chameleons is 2n= 36. This “primal chameleon” had six pairs of metacentric macrochromosomes and twelve pairs of microchromosomes, particularly small chromosomes. The Veiled chameleon, on the other hand, has a smaller number of chromosomes, namely only 2n=24. Using various genetic investigation methods, the researchers in the present study found that this karyotype probably arose through fusions. Microchromosomes apparently fused with each other twice, and micro- and macrochromosomes fused no less than four times. The latter, the so-called heterogeneous fusion between chromosomes of different sizes, is unusual for vertebrates. Normally, macro- and microchromosomes are located at different locations in the cell nucleus and are transcribed and replicated at different rates. However, this phenomenon is already known from alligators and turtles – for chameleons it is new.

Until now, it was also unclear which pair of chromosomes in the Veiled chameleon is actually responsible for the sex. In Chamaeleo chamaeleon, the second largest chromosome pair codes for sex. However, initial speculation suggests that in the Veiled chameleon the fifth chromosome pair (CCA5) may instead be the sex chromosome pair. The conjecture still needs to be validated by further research. It is also still up for discussion which gene is actually predominantly responsible for the development of the sex organs in the embryo – the researchers identified at least three possible genes on CCA5.

Identification of Iguania ancestral syntenic blocks and putative sex chromosomes in the Veiled Chameleon (Chamaeleo calyptratus, Chamaeleonidae, Iguania)
Katerina V. Tishakova, Dmitry Yu. Prokopov, Guzel I. Davletshina, Alexander V. Rumyantsev, Patricia C. M. O’Brien, Malcolm A. Ferguson-Smith, Massimo Giovannotti, Artem P. Lisachov, Vladimir A. Trifonov
International Journal of Molecular Sciences 23, December 2022
DOI: 10.3390/ijms232415838

Rhampholeon spectrum – not just one species?

Rhampholeon spectrum – not just one species?

Science

The pygmy chameleon genus Rhampholeon is mainly found in East Africa. Rhampholeon viridis, Rhampholeon spinosus, and Rhampholeon temporalis each live in clearly defined and isolated areas of Tanzania. Rhampholeon spectrum, however, seems to be the complete opposite so far: The species has an enormous range in western Africa. It extends from Côte d’Ivoire through Ghana, Togo, and Benin to Nigeria and the outskirts of Niger and Chad, then on through Cameroon, Equatorial Guinea, and Gabon into the Central African Republic as well as the Democratic Republic of Congo and the Republic of Congo. Researchers from the USA and Cameroon have now investigated genetically what is behind the wide distribution.

Samples from an island at the northernmost tip of Equatorial Guinea, several mountains in Cameroon, and samples from two areas in Gabon were examined. To the researchers’ astonishment, it turned out that Rhampoleon spectrum is by no means genetically identical everywhere. Two clades could be identified from the samples: One in the lowlands and one in the montane forest, where the chameleons are found exclusively above 700 m a.s.l. A total of five genetically distinct populations were identified, several of which may represent new, as yet undescribed chameleon species.

The lowland clade includes the population in Gabon, where chameleons were sampled from Ivindo National Park and animals in an area near the town of Mekambo. The second population of the lowland clade occurs at low altitudes on Mount Korup, a mountain of volcanic origin. Mount Korup is located in the protected national park of the same name in Cameroon on the border with Nigeria.

The montane clade of the Rhampholeon spectrum includes three populations. One population occurs on Mount Biao on the island of Bioko, which belongs to Equatorial Guinea. A second population is found on Mount Cameroon, an active volcano in western Cameroon not far from the Gulf of Guinea. The type specimen of Rhampholeon spectrum comes from Mount Cameroon. The locality mentioned in the first description, Mapanja, is only a few kilometres away from one of the places where individuals were collected in the present study. This population is therefore probably the “true” Rhampholeon spectrum, the so-called topotypic group. The third population of the montane clade is found on three neighbouring mountains in Cameroon: Mount Kupe, Mount Mangengouba, and Mount Nlonako. Together with Mount Cameroon and Mount Biao, all three belong to the so-called Cameroon Line, a mountain range of volcanic origin that stretches along the border between Cameroon and Nigeria from the sea to Lake Chad.

The researchers are also looking into the question of how the different populations might have evolved. The separation between Rhampoleon spectrum and the pygmy chameleons in Tanzania can be dated to the late Eocene around 40 million years ago. During this time, the previously continuous rainforests in West, Central, and East Africa broke up into smaller, sometimes isolated fragments. The Rhampoleon spectrum clade then split into lowland and montane populations in the Miocene around 11.1 million years ago. In the Miocene, tectonic movements led to the uplift of a low mountain range that extended from southern Cameroon to the south of the Republic of Congo. Rivers, deserts, and other geographical barriers changed. Somewhat later, about 9.3 million years ago, the population on Bioko Island split off. The island’s pygmy chameleons are thus older than the island itself – the researchers explain this phenomenon by the fact that the island must have been connected to mainland Africa via a land bridge in the past. The chameleons would therefore have colonised the island, found a home on the mountain, and only then became isolated from the mainland. However, the genetically identical population on the mainland could not be found – researchers consider it extinct. In the late Miocene, around 6.9 million years ago, the populations on Mount Korup and in Gabon emerged. Only at the transition from the Miocene to the Pleistocene, 5.2 million years ago, did the populations on Mount Cameroon and Mount Kupe emerge.

Further research on this topic will show whether new species are actually hiding under the name Rhampholeon spectrum – chances are good. It would also be interesting to investigate populations of the species that are not mentioned in this study. Because, of course, the Rhampholeon spectrum from southern and eastern Cameroon, continental Equatorial Guinea, southern Gabon, and the Congo could also be further, independent populations. Science remains exciting!

Diversification and historical demography of Rhampholeon spectrum in West-Central Africa
Walter Paulin Tapondjou Nkonmeneck, Kaitlin E. Allen, Paul M. Hime, Kristen N. Knipp, Marina M. Kameni, Arnaud M. Tchassem, LeGrand N. Gonwouo, Rafe M. Brown
PLOS One, December 2022
DOI: 10.1371/journal.pone.0277107

Fossil finds of Chamaeleo chamaeleon in Morocco

Fossil finds of Chamaeleo chamaeleon in Morocco

Science

There have only been a few fossil finds of reptiles from Morocco so far, especially concerning Agama bibronii and Chamaeleo chamaeleon. Archaeologists from the National Institute of Archaeology and Cultural Heritage (Institut National des Sciences de l’Archéologie et du Patrimoine, INSAP) in Rabat, Morocco, have now published an overview of Moroccan finds.

The rock cave of Ifri n’Ammar belongs to the Rif mountain range, which runs about 50 km away from the northeast coast of Morocco and is part of the Atlas Mountains. Ifri n’Ammar is located in a valley south of the town of Afso, on the border of two wadis. Since 1997, excavations have been led there by INSAP and the German Commission for Archaeology of Non-European Cultures (KAAK). Two Os prefrontale, two Os postorbitofrontale, three Os maxillare (upper jaw), six pieces of bone with acrodont teeth, and three vertebrae could be assigned to the family Chamaeleonidae so far. The distinction from fossil remains of agamas was quite clear: agamas have pleurodont teeth in the anterior region of the maxilla, whereas chameleons have only acrodont teeth. In addition, the shape and position of the nostrils differ. Agamas also do not have the bony tubercles and “crests” typical of chameleons. Since Chamaeleo chamaeleo is the only representative of the chameleons found in the Maghreb today, the fossils were attributed to this species.

The fossils were all found in a layer at a depth of three meters, which is assigned to the Middle Stone Age. The fossil remains are therefore between 83,000 and 171,000 years old, which is considerably older than the remains discovered so far for chameleons in Morocco (Tarofalt, Guenfouda) and Algeria (Gueldaman). The archaeologists assume that at that time the area around the site must have still been tree-covered.

It is partly questionable how the pieces of bone from Ifri n’Ammar arrived at the finding sites. Traces on some bones indicate digestion processes and thus that the associated chameleons were consumed as prey. So not all of the chameleons found there died a natural death. According to the traces, birds of prey and small carnivores such as the gundi (a North African rodent) or simply rats could be possible predators.

Agama bibronii (Sauria: Agamidae) et Chamaeleo chamaeleon (Sauria: Chamaeleonidae) d’Ifri n’Ammar (Rif oriental, Maroc)
Touria Moushine, Fethi Amani, Abdeslam Mikdad
Quaternaire 33 (03), 2022
DOI: 10.4000/quaternaire.16948

Chamaeleo gracilis in Taï National Park (Côte d’Ivoire)

Chamaeleo gracilis in Taï National Park (Côte d’Ivoire)

Science

Little is known about chameleons in the Republic of Côte d’Ivoire. Ivorian biologists have now confirmed the presence of various reptile species in one of the country’s national parks. For the first time, they have found Chamaeleo gracilis in Taï National Park, which matches its known range in West Africa.

Taï National Park is located in the southwest of Côte d’Ivoire in western Africa. The climate changes four times a year. From March to June there is a rainy season, in August it is dry, followed by a second rainy season in September and October and a second dry season from November to March. 40 areas, each 50 x 50 m in size, were surveyed. Of these, 18 were in primary forest (rainforest), seven in secondary vegetation with more shrubby growth, five in coffee or cocoa plantations, five in rubber tree plantations and five in rice fields. On each of 40 days, three researchers were in the demarcated areas for more than eight hours and visually scanned the surroundings for reptiles.

Chamaeleo gracilis was the only reptile observed exclusively in the rainforest. As is often the case with chameleons, a female was discovered laying eggs on the ground. The species was not found in secondary vegetation or agricultural landscapes.

First record of seven species of lizards in Taï National Park (South West, Côte d’Ivoire)
Kouadio Atta Léonard, Assemian N’guessan Emmanuel, Goly N’guessan Simplice, Keita Gaoussou, Tiédoué Manouhin Roland
International Journal of Zoological and Entomological Letters 2022, 2(2): 36-41
DOI: not available

Chamaeleo dilepis in traditional south african medicine

Chamaeleo dilepis in traditional south african medicine

Science

Researchers from North-West University in South Africa have investigated which reptiles are used by traditional healers and how much they actually know about the species used. They visited six medical shops and markets (muthi shops/markets) in Polokwane, Pretoria, Johannesburg, Pietermaritzburg and Durban. Twelve traditional healers were also visited, two each in Limpopo and Gautend and seven in KwaZulu-Natal. Healers who agreed to be interviewed were asked about the species and origin of reptiles they use. Samples were taken for genetic testing from 111 carcasses and tissue remains (some only bones with meat remains) offered for sale.

Of the 34 reptile species known so far from the literature to have been traditionally used in South African medicine, nine could be confirmed. The healers reported that they partly hunted the reptiles themselves and partly bought them from specialised hunters. To the astonishment of the researchers, reptiles killed in road traffic (“roadkills”) were also used by healers. For sale and use, the reptiles were preserved. Fat and internal organs were removed manually. The fat was kept in bottles as it could be sold individually. The organs were not used further. The carcasses of the reptiles were then rubbed with ash and salt and dried in the sun. All healers agreed that whole carcasses were rarely sold – usually customers only wanted to purchase certain body parts, as only these were known for their effects.

The flap-necked chameleon was already known to be an occasional species at traditional South African healer markets. Several Chamaeleo dilepis were also identified in this study, but they were only marketed with an umbrella term in isiZulu. Unwabu refers to any species of chameleon, not specifically Chamaeleo dilepis. For other reptile species, some of the healers’ names matched the identified species down to the species level. However, there were also quite a few misidentified specimens where completely different reptiles were identified by the healers than turned out to be the case in the genetics.

Barcoding and traditional health practitioner perspectives are informative to monitor and conserve frogs and reptiles traded for traditional medicine in urban South Africa
Fortunate Phaka, Edward Netherlands, Maarten van Steenberge, Erik Verheyen, Gontran Sonet, Jean Hugé, Louis du Preez, Maarten Vanhove
Molecular Ecology Resources [Preprint], 2022
DOI: 10.22541/au.166487945.53921162/v1

Species diversification in chameleons

Species diversification in chameleons

Science

From earlier studies, we know that the first chameleons evolved in the late Cretaceous, about 90 million years ago, on mainland of Africa. Around the border between the Cretaceous and Tertiary periods, about 65 million years ago, different species began to evolve. It is still unclear today which factors contributed to the diversity of species. Two researchers from Swansea University in Wales have now used various computational models of phylogenetics to investigate what might have influenced diversification (the splitting of chameleons into many different species).

First, they studied the diversification of chameleon species in Madagascar. In terms of evolutionary history, there are two points in time when chameleons apparently spread across the sea from mainland Africa to Madagascar. One is about 65 million years in the past, the other 45 million years. You could now think that the climatically extremely different habitats in Madagascar could have driven the evolution of the species very quickly after the spread across the sea. To the surprise of the researchers, however, no evidence of this was found. The species richness of chameleons on Madagascar must therefore come from the fact that chameleons spread there very early and thus simply had much more time to develop into different species than elsewhere.

Furthermore, the researchers investigated whether switching between two ecomorphs – from ground-dwelling stub-tailed chameleons to tree-dwelling chameleons with longer tails – had an impact on species diversity. Rather surprisingly, this did not seem to be the case. The evolution to tree-dwellers with longer tails occurred relatively early on one or two occasions. No evidence could be found that different ecomorphs accelerated diversification. Instead, speciation rates were found to slow down progressively over the last 60 million years. Only a very early dispersal event of the genus Bradypodion in South Africa around 10 million years ago was accompanied by a two- to fourfold diversification rate.

As a third focus of the study, the researchers examined the genus Bradypodion. During the climate change in the Miocene around 10 million years ago, South Africa changed a lot. Forests disappeared, leaving behind isolated forest habitats and, in between, savannahs, some of which are now so-called hot spots of biodiversity. Two of them, the Cape Floristic Region at the southwestern tip of South Africa and Maputuland-Pondoland-Albany on the east coast of South Africa, are home to a particularly large number of Bradypodion species. Each species is limited to a geographically very clearly defined area. The researchers, therefore, suspect that Bradypodion species have actually evolved faster under the influence of habitat change. It should be noted that the diversification rate of the genus Bradypodion is probably rather underestimated, as there are still many hidden species to be assumed.

Diversification dynamics of chameleons (Chamaeleonidae)
Stephen Giles, Kevin Arbuckle
Journal of Zoology, 2022
DOI: 10.1111/jzo.13019

Preferred perches in Bradypodion pumilum

Preferred perches in Bradypodion pumilum

Science

It has long been known that most chameleon species move around on branches. However, research into how and which branches they prefer to use has so far been based mainly on nocturnal observations. At night, chameleons are easier to find in bushes and trees because they usually sleep on the ends of branches and are easy to spot with a torch. However, less is known about the use of perches during the chameleons’ active time, namely during the day. The herpetologist Kristal A. Tolley from the Kirstenbosch Research Centre in Cape Town, South Africa, has now conducted a study to find out which perch sizes Bradypodion pumilum prefers at night and during the day.

It is known from other tree-dwelling reptiles that they tend to seek out thinner perches at night, but use different perch sizes during the day. The result of the study was all the more surprising: the branches used by Bradypodion pumilum did not differ in diameter or variety during the day and night. An astonishingly high range of branches was used overall. The only correlation found was with body size, which seems logical in principle: The larger the chameleon, the thicker the perches used.


Is it like night and day? Nocturnal versus diurnal perch use by dwarf chameleons (Bradypodion pumilum)
Krystal A. Tolley
African Journal of Herpetology
DOI: 10.1080/21564574.2022.2098392

Chamaeleo chamaeleon in Turkey

Chamaeleo chamaeleon in Turkey

Science

The European chameleon Chamaeleo chamaeleon inhabits a range that extends from North Africa through southern Portugal and Spain as well as Cyprus and Malta to Lebanon, Syria and Turkey. So far, however, very little is known about the populations in Turkey.

Turkish biologists have recently undertaken the first small study to change this state. They examined 29 European chameleons for their snout-vent-length and, using skeletochronology, for their age. 15 of them were males, 14 females. The animals studied were museum specimens from Dokuz Eylül University. They were collected in the surroundings of the Akyatan lagoon at earlier times. Akyatan is located in the south of Turkey directly on the Mediterranean Sea, about 200 km from the Syrian border. The nearest major Turkish cities are Mersin and Adana.

The average head-torso length of Chamaeleo chamaeleon from Akyatan was 85.34 mm, with females slightly larger than males. The smallest chamaeleon measured 59.71 mm, and the largest 106.84 mm. Thus, the studied population in Akyatan seems to be possibly somewhat smaller than the comparative populations in Spain and Egypt. However, the numbers of animals examined are too small to be able to make reliable statements about this. The age of the animals was between two and four years. The males reached sexual maturity after the first hibernation, while the females did not reach sexual maturity until the second year of life.

Age and body size of the Mediterranean Chameleon, Chamaeleo chamaeleon (Linnaeus 1758) (Lacertilia: Chamaeleonidae) specimens collected from Adana, Türkiye
Elif Yildirim, Nurettin Beşer, Can Yilmaz, Kamil Candan, Yusuf Kumlutaş, Çetin Ilgaz, Elnaz Najafi Majd
Commagene Journal of Biology
DOI: 10.31594/commagene.1104020