Potential new distribution areas of the European chameleon

Potential new distribution areas of the European chameleon

Verbreitung Science

The European chameleon (Chamaeleo chameleon) was historically found in some small areas of the Mediterranean and Central Asia. Today, however, it is much more widespread. It is now assumed that the animals were brought to their new distribution areas by humans and were able to reproduce there due to the favourable climatic conditions. Scientists have now investigated where there are further suitable habitats for the European chameleon and how the existing populations could develop over the next 50 years.

The three subspecies studied were Chamaeleo chamaeleon chamaeleon, Chamaeleo chamaeleon musae and Chamaeleo chamaeleon reticrista. The former is known from the southern edge of Portgual and Spain as well as from southern Italy, Algeria, Egypt, Libya, Malta, Morocco, Tunisia, the western Sahara and Yemen. The second subspecies is currently found in Jordan, Israel and Egypt. The third subspecies occurs between Greece and Turkey, in Cyprus, Israel, Lebanon and Syria, but is actually native to northern Africa and the Middle East. It was probably introduced by people in southern Spain and Portgual, but is now considered a native species there.

For the study, the existing literature, sampling by the author himself, OpenStreetMaps and information from the Global Biodiversity Information Facility (GBIF) were used, statistically processed and analysed. Climate, topography, habitat of the sites and connections of existing populations were used to predict potentially suitable new habitats.

A total of 553 Chamaeleo chamaeleon findings were included in the study. 22% of the finds could be assigned to urban areas, 21% to scrubland and 18% to agricultural land. Most of the finds were made at altitudes of 0 to 100 metres above sea level. Not surprisingly, the areas currently colonised by Chamaeleo chamaeleon proved to be very suitable habitat. Potential well-suited new distribution areas in the future could be the Iberian Islands between Murcia and the Algarve in Portugal, Sicily, Calabria, Apulia and Sardinia in Italy, Morocco, Tunisia, Libya, the region between Israel and Lebanon in the Middle East, Cyprus and all coasts and islands of the Aegean Sea. Overall, a progressive increase in all existing habitats of the European chameleon is expected over the next 50 years. The only exceptions to this are probably some regions in Tunisia and Turkey. Further habitat losses are assumed on the Aegean coast in Turkey and Israel. In Spain and Portgual, the distribution area could shift westwards.

Habitat suitability and connectivity modelling predict a latitudinal-driven expansion in the Mediterranean basin for a historically introduced reptile
Davide Serva, Viviana Cittadino, Ilaria Bernabò, Maurizio Biondi, Mattia Iannella
European Journal of Wildlife Resarch 70 (27), 2024
DOI: 10.1007/s10344-024-01780-9

The two graphics are both from the publication mentioned.

New hope for Calumma tarzan

New hope for Calumma tarzan

Verbreitung Science

Calumma tarzan, the Tarzan chameleon, was only described in 2010. It was named after the place where it was found, Tarzanville, a small village in the Anosibe An’Ala region in the centre-east of Madagascar. Due to the previously assumed very small distribution area, the species was immediately classified as “critically endangered” on the IUCN Red List.

In 2020 and 2021, Malagasy scientists searched for the species in many other places in eastern Madagascar – and promptly found it, as a recent publication reports. They searched 46 transects, each one kilometre long, in 23 different forest fragments. A further 28 transects, each 200 metres long, were examined in order to assess the population density. Calumma tarzan was found in 14 of the 23 forest fragments analysed. None of these occurrences were previously known. The species occurred at altitudes of 604 to 1048 metres. Population density estimates varied greatly. In some areas there are only 25 chameleons per hectare, in others more than three times as many, namely 78.

Only a few of the forest fragments are currently protected. This study therefore emphasises how urgent it is to establish further protected areas in Madagascar’s eastern rainforests. This is the only way to save the Tarzan chameleon.

New distribution records and population density of the critically endangered Tarzan chameleon (Calumma tarzan), eastern Madagascar
Alain J.V. Rakotondrina, Raphali R. Andriantsimanarilafy, Hanta J. Razafimanahaka, Achille P. Raselimanana, Rikki Gumbs, Caleb Ofori-Boateng, Jody M. Taft, Fanomezana M. Ratsoavina
African Journal of Herpetology, 2024
DOI: 10.1080/21564574.2023.2291358

Chameleons in Bobaomby (Madagascar)

Chameleons in Bobaomby (Madagascar)

Verbreitung Science

The Bobaomby complex is located at the northernmost tip of Madagascar, north and west of the largest coastal town in the north, Antsiranana (Diego Suarez in French). It consists of dry forest at sea level up to a maximum of 200 metres above sea level as well as extensive savannahs on karst rock and various rock formations. The area has not been protected to date.

Scientists from Madagascar conducted reptile counts in the Bobaomby complex in 2018. The counts were carried out in February and March, i.e. during the rainy season. Five different locations were analysed: Beantely, Antsisikala and Ambanililabe as examples of varying degrees of degraded dry forest, Anjiabe for its intact dry forest and Ampombofofo with relatively intact forest. To find animals, the visual survey was used on 25 days during the day and at night in selected transects, sometimes specifically in suitable habitats such as leaf axils or under dead tree trunks, and pitfall traps along erected fences were also used.

A total of 42 reptile species have been recorded. All of them, except one gecko species, originally only occur on Madagascar, while two other gecko species are now also found on neighbouring islands. There is a small novelty among the chameleons: the leaf chameleon Brookesia ebenaui was recorded for the first time in Bobaomby, more precisely in Beantely. Brookesia stumpffi and Furcifer petteri were found in Beantely, Anjiabe and Ampombofofo. Furcifer pardalis and Furcifer oustaleti occurred as expected throughout the whole Bobaomby complex.

The authors suggest that the Bobaomby complex – especially the three forests where most of the reptiles were found – should be protected to preserve the local herpetofauna.

Overview of reptile diversity from Bobaomby complex, northern tip of Madagascar
Randriamialisoa, Raphali R. Andriantsimanarilafy, Alain J. Rakotondrina, Josué A. Rakotoarisoa, Nasaina T. Ranaivoson, Jeanneney Rabearivony, Achille P. Raselimanana
Animals 13: 3396, 2023
DOI:  10.3390/ani13213396

Photo: Furcifer petteri, male, in the north of Madagascar, photographed by Alex Laube

The Indian Chameleon in Solapur (India)

The Indian Chameleon in Solapur (India)

Verbreitung Science

It has long been known that the Indian chameleon occurs in Maharashtra. A recently published survey study has even found evidence of it in an area near Solapur that is covered only with grass and bushes.

The area studied is a 15 km² area of semi-arid grassland around a site earmarked for an airport at an altitude of 450 to 500 metres. The nearest village is Boramani, a small town just outside the city of Solapur in the state of Maharashtra in western India. For one year, about half of the grassland was surveyed four times a month for the presence of reptiles. Squares of 50 metres x 50 metres were laid out, each at least 300 metres apart. Each observation period consisted of five hours and only observations with the naked eye.

During the study period, 888 individuals of 14 different reptile species were recorded. Of these, more than 300 were Sitana laticeps, a fan-throated lizard. Among the species found were two Chamaeleo zeylanicus. The activity of the lizards increased from March, stabilised during the monsoon season in June-July and then declined again from August.

The authors argue in favour of protecting the grassland area due to the existing biodiversity. This should prevent the construction of the airport and thus the disappearance of the habitat.

Ecology of lizards in an ecologically significant semi-arid grassland patch near Solapur, Maharashtra, India
Mahindrakar Yogesh Y., Waghmare Akshay M., Hippargi Rajshekhar V.
International Journal of Zoological Investigations 9 (2) 2023, pp. 210-223
DOI: 10.33745/ijzi.2023.v09i02.022

Findings on the synonyms of Trioceros ituriensis

Findings on the synonyms of Trioceros ituriensis

Verbreitung Science

Synonyms for the Congolese Ituri chameleon (Trioceros ituriensis) have existed for several decades. A recent publication by the herpetologist Wolfgang Böhme questions whether two of them could be separate species.

The US herpetologist Karl Patterson Schmidt described the chameleon as Chamaeleon ituriensis in 1919. At that time, Schmidt gave Medje, Ituri Forest, in the Democratic Republic of Congo as the type locality. He already noticed the external similarity to Chamaeleon johnstoni affinis, which is why he gave exactly that as a synonym of his Chamaeleon ituriensis. At the same time, Chamaeleon johnstoni affinis must not be confused with today’s Trioceros affinis, a separate species from Ethiopia that had already been described in 1845. In the course of the 20th century, Chamaeleo johnstoni affinis was placed in the genus Trioceros, sometimes thought to be a subspecies of its own, sometimes not. Böhme states that Trioceros johnstoni affinis is definitely a synonym of Trioceros ituriensis. Differences between Trioceros johnstoni and Trioceros ituriensis are the body size, the “reversed” sexual dimorphism (in T. ituriensis the females are larger than the males), a white line along the belly, several rows of enlarged scales along the side of the body, conical scales on the sides of the throat and the absence of rostral and preocular horns in male T. ituriensis.

However, the author is not sure about the species status of Chamaeleo laevigularis. The species was originally described from South Africa in 1926, then considered a synonym of Trioceros johnstoni and last identified as T. ituriensis by Tilbury in 2010. Böhme considers, because of different scaling of the throat, whether either a wrong locality was noted in the first description or it is a separate species, but could be extinct or lost.

Böhme also comes to the conclusion that Trioceros tremperi, which was described by Neĉas in 1994, could possibly also represent an already extinct species or a lost species and that the locality simply corresponded to incorrect information. Trioceros tremperi was last given as a synonym of Trioceros ituriensis by Tilbury 2010 and Spawls 2018. The chameleons had not been found in the type locality in Kenya before.

Documenting synonymies in Trioceros ituriensis (Schmidt, 1929) with remarks on sexual dimorphism in chameleons (Squamata: Chamaeleonidae)
Wolfgang Böhme
Revue Suisse de Zoologie 130(2), 2023: pp. 521-264
DOI: 10.35929/RSZ.0099

Photo: Trioceros ituriensis in the Budongo forest, Uganda, photographed by Katja Rembold

Concerning Florida’s introduced panther chameleons

Concerning Florida’s introduced panther chameleons

Verbreitung Science

The “Sunshine State” Florida in the USA has the largest number of non-native species of reptiles in the world because of its warm climate. The panther chameleon (Furcifer pardalis) is one of the invasive species, i.e. those that do not actually belong in Florida but are now reproducing there. A study has now investigated the question of what the human inhabitants of Florida actually think of the chameleons.

It has been discussed for a long time whether panther chameleons belong to the species that were deliberately released for the purpose of “ranching”, i.e. to collect the offspring of the released chameleons for sale. That private individuals collect panther chameleons is not in dispute. According to the authors, ranching populations in Florida are mostly kept secret. They became aware of a small population in Orange County via social media in 2019. They then searched for the animals at night with torches and actually found 26 panther chameleons during several walks. They encountered private individuals on several occasions who were also looking for chameleons.

In 2020, questionnaires were distributed in person and via flyers with QR codes to 248 households located within the presumed 0.9 km² distribution area of the panther chameleon population. They were asked about concerns regarding the occurrence of panther chameleons, but also about existing knowledge about invasive species in general. The residents were also divided into three areas: A core region where chameleons had been observed several times, a peripheral region with few findings, and an outer region where no chameleons had been sighted at all.

44 households answered the questionnaire.  In fact, all 11 interviewed residents in the outer region had not sighted any chameleons. Of the 33 residents interviewed in the core and peripheral region, about a third said they had already observed panther chameleons. The same number had seen the light of torches at night. 86% of the residents surveyed knew that panther chameleons are not actually native to Florida. Only a few residents said they were concerned about the occurrence. Seven residents had approached collectors with torches and said the collectors had all said they were looking for chameleons for research purposes. Only one of the collectors had said he/she was looking for animals to sell, according to the residents. One resident reported an altercation after strangers entered his property several times looking for chameleons. Another resident called the police because of a whole group of collectors on the neighbouring property.

Unfortunately, the questionnaire was given out after the search efforts of the authors themselves, so it is not apparent from the responses how many of the encounters were indeed with people looking for chameleons for sale purposes. The publication is also a preprint, so no review process has taken place yet.

Colorful lizards and the conflict of collection
Colin M. Goodman, Natalie M. Claunch, Zachary T. Steele, Diane J. Episcopio-Sturgeon, Christina M. Romagosa
Preprint, 2023
DOI: 10.1101/2023.08.10.552819

Picture: Alex Laube

Unknown chameleon discovered in Ivohiboro forest (Madagascar)

Unknown chameleon discovered in Ivohiboro forest (Madagascar)

Verbreitung Science

There are still almost unexplored areas on Madagascar today. The Ivohiboro rainforest is located in the southeast of the island in the protected area of the same name, southwest of the southernmost foothills of the Andringitra Mountains. The forest itself is about 8.58 km² in size and thus only occupies a small part of the protected area. It is surrounded by savannahs and spans altitudes from 650 to 1460 m above sea level. The protected area is currently managed by local organisations and Madagascar’s Ministry of Environment. The last expedition to explore the Ivohiboro forest took place in 1924. Since 2016, researchers from the USA and Great Britain have now undertaken six expeditions to the small forest to study the biodiversity of plants, birds, mammals, reptiles, and amphibians there in more detail.

To detect reptiles and amphibians, the forest was divided into nine transects of about 200 x 20 m, each more than 200 m apart. The transects were searched for several days and nights. All animals found were documented and, if possible, identified down to genus or species level.

As a result, the scientists were able to identify 107 species of vertebrates and 219 plants. This enormous diversity of species underlines the importance of preserving the forest in terms of species conservation and indicates a well-functioning ecosystem. Among the species found were two chameleons: a Palleon species and a small Calumma. Unfortunately, the publication does not provide any further information on the former. The small Calumma had a conspicuous blue coloured rostral appendage, as it is found in Calumma linotum or Calumma boettgeri in the far north of Madagascar. As genetic studies are still lacking, it is unclear whether these chameleons are an extremely wide range extension – Ivohiboro lies about 1000 km south of the ranges of Calumma boettgeri and Calumma linotum – or whether it is perhaps even a new, as yet undescribed species.

A surprising haven: The biodiversity of an old-growth forest amidst a scorched landscape in Madagascar
Beatriz Otero Jimenez, Ren Montaño, Ryan S. Rothman, Rachel C. Williams, Patricia C. Wright
Conservation Science and Practice, 2023
DOI: 10.1111/csp2.12993

Chameleons in the Montagne des Français (Madagascar)

Chameleons in the Montagne des Français (Madagascar)

Verbreitung Science

The Montagne des Français is a limestone massif with dry forest in northern Madagascar. It reaches up to 425 m above sea level and is within sight of the largest coastal town in the north, Antsiranana (French Diego Suarez). It has been a protected area since 2007. Scientists from Madagascar and the USA conducted counts of reptiles and amphibians in the Montagne des Français in 2014 and 2020.

Counts were made in January and May, i.e. during and at the end of the rainy season. In 2014, the focus was on the region around Andavakoera, while in 2020 it was on Sahabedara, Ampitiliantsambo, and Andavakoera. In order to find animals, the search was conducted during the day and at night along predefined paths, partly in suitable habitats, and partly in pitfall pits.

A total of 20 amphibian and 50 reptile species were recorded. Four new amphibians and one reptile were found for the first time in the Montagne des Français. The snake Langaha pseudoalluaudi was discovered again for the first time since 2007. Among the chameleons, there were minor new discoveries. Brookesia stumpffi could only be found in 2014, but no longer in 2020 – however, due to the relatively wide distribution of the species, this should not be a problem for the entire population. Brookesia tristis, one of the smallest chameleons in the world, was also only seen in 2014. Here, the body size, which makes it very difficult to find, and the time of year (May is relatively late for this species) could play a role. Brookesia ebenaui was detected in Andavakoera in 2014 and in Sahabedara in 2020. The two tree dwellers Furcifer oustaleti and Furcifer pardalis were found in both years in Andavakoera and Ampitiliantsambo. Furcifer petteri, on the other hand, was present at all the sites surveyed in both years.

Amphibians and reptiles of the “Montagne des Français”: Update of the distribution and regional endemicity
Herizo Oninjatovo Radonirina, Bernard Randriamahatantsoa, Rabibisoa Harinelina Christian Nirhy, Christopher J. Raxworthy
Preprint
DOI: 10.20944/preprints202306.1499.v1

Photo: Furcifer petteri on Madagascar, photographed by A. Laube

The Arabian Chameleon in Abyan (Yemen)

The Arabian Chameleon in Abyan (Yemen)

Verbreitung Science

The majority of overview studies on the occurrence of reptiles in Yemen date back to the 1990s. More recent research is mainly based on areas close to cities, but less on more remote regions. Two biologists from the Universities of Aden and Abyan have recently published a survey on the occurrence of reptiles in Abyan.

The Abyan governorate is located in the south of Yemen on the Arabian Peninsula. It borders the Gulf of Aden to the south and the governorates of Aden, Lahji, Al Bayda, and Shabwa to the west, north and east. 44 areas in Abyan were surveyed within a whole year. Reptiles were caught by hand and some were merely documented, while others were killed and preserved. A total of 202 animals were examined.

A total of 24 different reptile species were found. Chamaeleo arabicus was found in the districts of Lawdar, Zinjibar, Khanfir and Jayshan. Of the 23 finds, most were made in western Khanfir, not far from the town of Zinjibar. Two chameleons were found in northern Lawdar and only one in southern Jayshan. The authors point out that the chameleons are mainly found in cultivated landscapes.

Distribution of lizards in Abyan Governorate, Yemen
Salem M. Busais, Wafa A. Abo-Alib, Hasan M. Alrahowi
Electronic Journal of University of Aden for Basic and Applied Sciences 4 (1), 2023
DOI: 10.47372/ejua-ba.2023.1.220