Black file snakes are poisonous

Expedition 2008 - Tanzania / The travel report


The Exo Terra Expedition 2008 took us to the mountains in the east and the highlands in the south of the Republic of Tanzania in East Africa. The main goal of this expedition was to reveal the biodiversity of amphibians and reptiles in these regions and to get a better understanding of the species that inhabit these complex ecosystems.

Some of the animals you will see in this film were filmed and documented for the first time in their natural habitat. These images add tremendously to the scientific community. But they are also extremely important for the herpetologists who observe, keep and breed these species in terrariums.


The expedition left Dar es Salaam, Tanzania's largest city. Here the team had equipped itself with provisions for the journey through the dense jungle, the wide plains and over the remote mountain ridges. The first destination was the Kimboza Forest near the Uluguru Mountains. These mountains in eastern Tanzania are one of the most important mountain ranges in Africa for the conservation of biodiversity.

The Kimboza Forest is one of the oldest in Africa and since the ecosystem has remained untouched by climatic and geographical changes for an estimated 25 million years, expectations were high. This forest is home to one of the most impressive geckos ever seen: the Lygodactylus williamsi.

One of the first reptiles the team found was a Nile monitor that was looking for food in the middle of the gravel road to the Kimboza Forest. The Nile Monitor, Varanus niloticus, is one of the largest members of the monitor lizard family. However, these animals, which actually live in the water, also have sharp claws for climbing, digging, defense or to tear at their prey. Nile monitors are carnivores and will eat everything: from frogs to small mammals and from crocodile eggs to carrion.

The camp was set up in front of a village on the edge of the Kimboza forest. The great African house gecko, Hemidactylus platycephalus, seems to be quite common in this area. This nocturnal gecko has been seen basking in huts and trees in the late afternoon. Like all geckos it is Hemidactylus platycephalus an opportunistic eater and eats almost everything that comes his way and fits in his mouth. This large spider was also swallowed down in the end ...

Many species of reptiles and amphibians are only active during the night and hide during the day. The team set out after sunset to observe the nocturnal herpetofauna in the Kimboza forest. The first creature our team spotted in the clutter of points was the extremely venomous green tree snake, Thelotornis capensis mossambicanus. The green tree snake is one of the numerous snakes with black fangs. Their bite is extremely venomous and can be fatal. The tree snake's venom is hemotoxic. It works very slowly and bites are rare. No antidote has yet been developed. Well-known German herpetologist Robert Mertens died after being bitten by a green tree snake that he held in captivity. The tree snake hides in trees and usually prey on lizards, frogs and sometimes birds. Often enough, however, it also stays near the forest floor to steal forage here as well.
The black snake of files Mehelya nyassae, moves exclusively on the ground and feeds on lizards and frogs. Although the file snake is quite common in some regions, it is very mysterious and rarely seen. When these snakes feel threatened, they move jerkily and secrete a foul-smelling substance from glands on the tail.


Although chameleons are diurnal, it is sometimes easier to find them at night while they are sleeping. When night falls, the chameleons become paler than their surroundings. This makes it easier to spot them. Chameleons tend to move to the far end of a branch to stay out of areas where predators like snakes look for prey. Most species drop instantly when they feel the vibrations and movements of a predator on the branch.

This rare chameleon with a nasal process, Kinyongia oxyrhina, was found while it was sleeping on a tiny branch. The stub tail chameleon, Rieppeleon brevicaudatus, can easily be found at night as his preferred sleeping places are very special. These stump tail chameleons, also known as leaf chameleons, spend the night on leaves or branches between 50 cm and 1 meter above the forest floor; often near clearings, paths and streams. The males of the stubby-tailed chameleons have a longer tail and a more prominent crest on the back. Rieppeleon brevicaudatus is able to squeeze its body sideways and develop a streak on its side, making it look like a dead leaf.

These stub-tailed chameleons only show their full potential during the day: when they run, it looks like the movements of leaves. The distinct jerky movements and the shape and color patterns of the animals mean that both predators and prey can easily overlook these remarkable animals. This male shows how he holds his body in position in relation to the branch. It hesitates to move forward so as not to increase the chance of possibly being seen.

This boy Kinyongia oxyrhina also shows a deception maneuver. It flattens its body to one side and disappears almost completely behind the thin branch. Its body is so extremely flat that only a few parts of the body protrude from behind the branch. Also, the animal will stick as close to the branch as possible to prevent detection. Do you see the subtle, yet obvious, color change in this two-minute sequence in fast motion?

The ragged chameleon, Chamaeleo dilepis, is one of the most common chameleon species in Africa. These formidable animals are common in central and South Africa, where they usually live on the edge of forests, in bushland, and in the savannahs. The animals we found here do not have tarsal spurs. This could be an indication that these animals actually Chameleo roperi are; a species that is usually found further north. The Chamaeleo dilepis has lobe-like structures that protrude from his head helmet. Hence the name "lobed chameleon". Part of the threatening gesture of the Chamaeleo dilepis is to move these "lobes" forward. At the same time it opens the mouth, flattens the body laterally and inflates the neck. Like all chameleons, the lobed chameleon is known for its ability to change color.

The color palette goes from dreary brown or black to lively green, white or yellow. Chameleons have chromatophores in their outer skin layer that are controlled by the brain. This enables them to consciously change the color in order to adapt to their environment; depending on the mood or even the assessment of a situation. Depending on the type of predator it is facing, a chameleon will change its color to more closely match the colors of its surroundings. If it encounters a bird, it will try to adapt to its surroundings even more closely than if it encounters a snake, since snakes cannot see as well as birds.

When male chameleons fight each other for supremacy, the colors indicate their mood. They then display bright, flashy colors to either intimidate a fellow soldier or to please a female. The ability to change color also makes thermoregulation easier. If the animal is darker in color, it will absorb the heat from the sun faster and will therefore not have to sunbathe for as long. This more efficient absorption of thermal energy means that the chameleon has more time to hide from predators or to hunt for food. However, if the environment is too hot and the chameleon cannot get into the shade quickly enough, it will lighten its skin pigmentation to reflect the sun's rays. This keeps the animal cooler than if it had to keep its darker pigmentation. The same technique is used to filter UV rays.


The Kimboza Forest is the Terra Typica and so far the only known place where the sky-blue dwarf day gecko, Lygodactylus williamsioccurs. The team searched deep in the forest to find this bright blue lizard. In these dense forests, most day gecko species live on plants or trees with smooth surfaces, such as palm trees, bamboo or pandanus species. This is the type of vegetation that we targeted first ... and with immediate success.

The first light blue male was on a large one Pandanus rabaiensis found. Once the preferred vegetation was identified, it was fairly easy to find the geckos. Lygodactylus williamsi can only be found on the 2 - 5m high leaves of the Pandanus rabaiensis. The pandanus palms are only found in certain areas and are grouped together in the forest. Lygodactylus williamsi occurs relatively frequently in its limited area.

Geckos are very territorial with one male, one to three females and a few juveniles on each pandanus palm. The geckos emerge from the heart of the pandanus in the early hours of the morning, retreat during the hottest hours of the day, and emerge again in the late afternoon. Lygodactylus williamsi feeds on ants, spiders and flies. The Lygodactylus williamsi Males can be up to 8 cm long. The females are a bit smaller.

The males are light blue with a black neck and yellow-orange belly. The females are greenish with a coppery shade. They have little black on the neck and only a few stripes or V-shaped markings. Usually the two sexes differ in a clear dichromatism. However, half-grown males can easily be mistaken for females. Like all chameleons, it changes too Lygodactylus williamsi its color when it feels threatened: the males from light turquoise to almost black and the females from green to brown. This species is without a doubt the most spectacular member of its genus.

Another member of this genus was found on the other side at the edge of the forest opposite the Uluguru Mountains. Lygodactylus grotei seems to prefer coconut palms on the edge of the forest. Each palm houses a male with several females and young animals.

The relatively common and widespread Lygodactylus luteopicturatus lives near human settlements and can also be found around the camp. The mountain dragons also live in these higher forest regions.


Next we did research in Mikumi National Park. This park borders on the northern border of Africa's largest game reserve - the Selous. The road from Dar Es Salaam to Iringa runs right through the park. Hence, this is the most accessible part of the 75,000 square kilometer wilderness that extends almost to the Indian Ocean.

The wide horizons and the enormous number of wild animals of the Mkata floodplain, the heart of the Mikumi, are comparable to the Serengeti. The mammalian fauna consists of impalas, zebras, wildebeest and buffalo, whose herds roam the floodplains. This region with its many wild animals is the hunting ground for many prides of lions. Elephants and giraffes look for food on single acacias and baobabs. Here you will also find small shadow islands.

During the dry season, animal life is concentrated in the Mikumi water holes, which are inhabited by hippos and crocodiles. The vegetation consists of savannah grass, speckled with acacias, baobabs, tamarinds and some rare palm trees. Very little is known about the reptile and amphibian populations, as research mostly focuses on the mammals and birds.

The Exo Terra team was particularly interested in geckos that live in solitary acacias and baobabs. This habitat is difficult to explore due to the large number of elephants, buffalo and lions. It appears that almost every acacia tree in this floodplain is from a yellow-headed dwarf gecko, Lygodactylus luteopicturates, is inhabited. The males have a yellow head - hence the name - and a grayish blue body. The females have a less noticeable color. Closer observation of these geckos revealed an extremely interesting case of trophobiosis with a symbiotic relationship between one living being that offers food and another living being that ingests it.

Many geckos have been found nearby or right under giant scale insects. These insects are known to produce honeydew; a sticky, sugary substance that they secrete when they feed on sap. Honeydew is often the secretion of scale insects and cicadas and is often the basis for trophobiosis. After digestion of the ingested plant sap in the digestive tract of the scale insect, the residues are excreted as honeydew. Many insects, such as ants, flies or butterflies, as well as nectar-eating birds, eat honeydew that has fallen on plants or other surfaces. However, some animals ingest the honeydew droplets directly from the insects. This behavior is widespread among ants.

This remarkable behavior was filmed for the first time during the Exo Terra Madakascar expedition: Phelsuma klemmeri makes use of a cicada larva and some ants wait patiently for their turn. Phelsuma vanheygeni and some LygodactylusSpecies have also been observed feeding on several leafhoppers. It is believed that this is how the geckos take in food and the sap-eating insects in return are protected from natural enemies by the geckos and ants. This is the first case of trophobiosis to be documented between reptiles and insects on the African continent. The fact that reptiles usually hunt insects makes this behavior even more extraordinary.

When night fell over the savannah and it seemed as if the lions should get some more rest the next night, the Exo Terra team prepared the departure for the Poroto Mountains the next morning.


The Poroto Mountains are located in the southwest of the country, near Lake Malawi. The Exo Terra team took a short break in Iringa to stock up on food and water for the next few days in the rainforest. With the off-road vehicle it was relatively easy to bring all the heavy equipment to the starting camp deep in the forest. Millions of tsetse flies welcomed the team into a clearing in the forest while the base camp was being set up.

In the days that followed, the forest was systematically searched for the various endemic chameleon species that occur in this mountain forest. At the edge of the impressive Ngozi crater, that became rare Rhampholeon nchisiensis found. It resembles a dead leaf and is usually brownish or greyish with two or three thin, dark streaks across the flank. There are often some blue scales at the eye sockets, which distinguish the Rhampholeon nchisiensis from most other species.

How Rieppeleon brevicaudatus These chameleons also look for food on branches and point about 50 cm to 1 meter above the forest floor and sleep here. This species can turn his eye socket blue. This makes it a stunning chameleon to keep as a terrarium animal. The tail of Rhampholeon nchisiensis is short and blunt. In the females it is even shorter. Adult Rhampholeon nichisiensis can grow up to 6 cm.

The first species to be found was the three-horned chameleon or Chamaeleo fuelleborni. This species actually only occurs in the Poroto Mountains; but it is that Chamaeleo jacksonii from Mount Meru and the Chamaeleo Werneri from the Usambara and Udzungwa Mountains very similar. The scales on the head of the Chamaeleo fuelleborni seem a lot rougher. The overall size of this chameleon is somewhat smaller and they only grow to be 8 inches tall. The male Chamaeleo fuelleborni has 3 well-defined horns consisting of rings, which are also smaller than at Chamaeleo jacksonii and Chamaeleo Werneri. The females have 3 very small horns made up of rings. The middle horn on the nose is a little longer. The males show territorial behavior and use their horns to ward off opponents.
Here you can Chameleo johnstoni see from the Ruwenzori in Uganda with this behavior.

Like many other species that live in higher regions, this is also Chamaeleo fuelleborni ovoviviparous. This means that the eggs develop in the female and the animals hatch when the female lays the eggs. Four to fifteen live pups are born in a single litter each year. Chamaeleo fuelleborni can easily be found at night while it sleeps on the extreme end of a branch or twig in order to spot predators such as snakes in good time.

Chamaeleo incornutus is a small to medium-sized species of chameleon that does not grow to be 20 cm tall. This species lives in bushes in the rainforests of the Ukinge, Ubena, Rungwe and also the Poroto Mountains in Tanzania. They have a large lobe on the back of the head and a small comb on the back, which consists of varied, conical scales that are relatively far apart. The Chamaeleo incornutus can easily be from the Chamaeleo fuelleborni can be distinguished, since both the females and the males do not have horns. The non-existent lobes on the back of the head and the finer scales distinguish the sympatric Chamaeleo goetzi from the other species of this southern plateau.

Two completely new reptile species were discovered during the Exo Terra expeditions. During the Madagascar expedition in 2004 it was Phelsuma vanheygeni and during the 2007 Gabon expedition a day gecko became the Genus Lygodactylus discovered.

Now the Exo Terra team has succeeded in documenting a completely new species of chameleon of the genus Kinyongia. This new style seems with that Kinyongia oxyrhinum from the Ulunguru and Udzungwa Mountains and to the Kinyongia tenue from the Usambara Mountains. It is different from the Kinyongia oxyrhinum through a smaller horn on the front of the head, the higher helmet and through larger scales on the head. The main difference between the new species and that Kinyongia tenue is the overall length and size of the helmet, which is much higher than when Kinyongia oxyrhinum is. A single specimen was found in the low scrub about 1 meter above the forest floor. So far, this chameleon species is only known from this single specimen and is currently being described. It seems even rarer than that Kinyongia oxyrhinum, of which only twelve specimens have been found so far.

One of the first frogs to appear shortly after the first rain of the season is the blue-footed forest climber frog, or Leptopelis vermiculatus. These frogs inhabit the dense treetops of the humid, tropical rainforest at altitudes between 900 and 1800 meters. Leptopelis vermiculatus grows up to 85 mm in size and comes in two distinct color variants: once light green with small black spots on the back and once in brown with a black pattern. The animals in the Poroto Mountains are brownish, but have some green spots and are something in between the two color patterns. Compared to the body size, the eyes are very large. They are gold in color with brown lines and spots. The big toes are used when climbing and to stick to the leaves after long jumps.


In the early morning the wagons were reloaded and we went to Lake Malawi to look for chameleons and day geckos. The road to this lake is challenging and little wildlife is seen here. The natural habitat in this region is completely out of balance. The only vegetation to be found here is the cultivated plants and fruit trees that are found in many gardens on the edge of this gravel road.

With the mighty Livingston Mountains as a backdrop, the lake is overwhelming. It is the third largest lake in Africa; 550 km long, 75 km wide and in some places it is up to 700 meters deep. From a biological point of view, the lake is extremely varied. It contains around 30% of the world's known cichlid species - the ideal place for the Exo Terra team to add some catfish to the otherwise rather meager meal.

On the way back some samples were taken from the Kiwira River; but without success. However, we were able to find a dull gray gecko in a barren tree on the riverbank. It was Lygodactylus capensis; probably the most common species in this genus. This day gecko is found in eastern and southern Africa; from just beyond the equator to the northern Cape Province in South Africa.

The green vegetation and the fertile fields quickly turn into a dry grassy landscape and savannah once you have passed the city of Mbeya. The road back to Iringa is overcrowded and there is no point in exploring it. There are usually not as many reptiles and amphibians in the savannah as in the humid forest areas. But the team really wanted to explore one of the drier regions: the Ruaha National Park. This is the second largest national park in Tanzania, but it is superior to all others in terms of rich biodiversity thanks to its unique location. Most of the national park is located on a 900 meter high plateau, whose hills, valleys and plains make this region unique and beautiful.

Ruaha protects a vast area of ​​rugged, semi-arid bushland that is characteristic of central Tanzania. The park's lifeline is the Great Ruaha River, which flows as a torrent along the eastern border during the rainy season. After the rainy season, the current decreases and valuable pools surrounded by sand and rocks are spread across the country. During the dry season, most animals can be found in or near these pools. So the fauna of the park is even closer together.

Impalas, kudu, waterbuck and other antelope species risk their lives for a sip of this vital water. The risk is great as it is very likely that you will encounter one of the twenty or more prides of lions that dominate the savannah. In a relatively small section of the Great Ruaha River and its seasonal tributaries, the team came across at least three prides of lions that were either resting or defending their fresh prey. This agamen female Lionotus dodomaehas nothing to fear; it's just too small. In addition to the lions, a large elephant population makes exploring the low bushes and thickets extremely difficult and dangerous.

The team hopes that Chamaeleo dilepis to be found in this area to get a better understanding of the differences between this species and the subspecies in this complex. The subspecies found in this region is Chameleo dilepis dilepis. The Chameleo dilepis dilepis is usually the largest species in the “Dilepis” complex and the males have a clearly defined tarsal process. The rule color of the members of this complex is green, but the animals can also have other colors such as yellow, black, orange, white or brown. All of the species in this “Dilepis” complex have a stripe on the side that is usually white. This strip runs from the back of the head to the end of the body. It is very likely that other taxonomic variants occur in this “Dilepis” complex. Some subspecies probably belong to the nominate form and some others become synonyms of what is now called Chamaeleo dilepis dilepis referred to as.

The rainbow skink Trachylepis margaritifera, lives on rocky formations along the Ruaha River. The males behave very territorially and bask in prominent positions in order to present their beautiful colors. The females get along easily Trachylepis quinquetainiata confused as they have a similar color scheme.

Other guests who can frequently be encountered on the rocks along the riverbank are the Agama lionotus dodomae. The males are very colorful and definitely the most eye-catching lizards in this region. It is obviously the peak of the mating season as the animals show their most striking colors. The males behave very territorially at this time. The colors of the females are less noticeable, but there are more females than males.

A species rarely found in this region is the leopard tortoise, Psammobates pardalis pardalis. These animals hide in the thicket or under shady trees during the heat of the day.

In Ruaha it can get very hot during the day and many animals seek shelter in the shade of the larger trees or stand in the remaining pools of the Ruaha River. Besides elephants, hippos and crocodiles are the only creatures that go into the water to escape the extreme heat. Even at these extreme temperatures, the animals come and go to find a little refreshment in what is left of the river.

The next research area is cooler and definitely wetter as this area is high in the Udzungwa Mountains. Udzungwa is the largest and most biologically diverse chain of the great forest-covered mountains that rise majestically behind the bush-covered coast in eastern Tanzania. The entire mountain range is known as the Eastern Arc Mountains. This archipelago with individual massifs is also known as the Galapagos of Africa because there is a veritable cornucopia of endemic plants and animals. Among the ancient mountain ranges of the Eastern Arc, only the Udzungwa was granted national park status. Furthermore, it is unique in Tanzania that the dense forest spreads over heights of 250 meters up to 2,000 meters without interruption. The mountains to the east are small and rugged. Each area has a patch of remaining, dense, high-rainfall tropical rainforest that forms lush islands in a sea of ​​dry savannah vegetation. The climb from the park's headquarters to the starting camp is steep and it gets wetter as the altitude increases. It takes about a day to reach the camp. Immediately after arrival, an urgently needed meal was prepared for the entire team in the makeshift field kitchen.

The main focus in these mountains is once again on the chameleons and geckos. But many other creatures such as millipedes, scorpions, beetles and butterflies were also found during the explorations. The first chameleon to be found is the stubby-tailed chameleon or Rieppeleon brevicaudatus. Although many striped morphs have been found, it appears to be the same species as near the Uluguru Mountains in the Kimboza Forest.

Chamaeleo deremensis, the Usambara three-horned chameleon is without a doubt one of the rarest large chameleons. It is usually found in other massifs in the Eastern Arc Mountains, namely the Usamabaras and Ulugurus. Now it has been documented for the first time in the Udzungwa Mountains. Here the species occurred near the Saje waterfall; at heights between 300 and 700 meters. Chamaeleo deremensis is one of the most evolutionarily developed chameleons due to its complex lung structure. They are a squat species and, in relation to their overall length, have a short tail and a high crest on the back. The helmet is smooth, flattened and elongated and ends in a spherical, small back of the head flap. The adult body color is medium to pale green with three or four pale yellow stripes dashed from the eye to the center of the body. Individual white-gray, blue, red, or brown spots and stripes are sometimes present. Sometimes when the animals are excited or stressed, dark green or black spots appear and the colors become lighter. Young animals have the same color patterns as the adult animals; however, on a navy blue background.

The male Chamaeleo deremensis have three large ringed horns that are proportionate to the size of the chameleon and other three-horned chameleon species such as the Chameleo werneri, are relatively small. The Chamaeleo deremensis differs from that Chameleo werneri, which occurs in the higher regions of the Udzungwa Mountains, due to its longer body size and the high crest on the back. The feminine Chameleo deremensis has no horn at all. Even the bud scales of the horns, as seen in other three-horned chameleons, are not present here. Both sexes have the same color scheme and are comparable in size when fully grown.

Still convinced of finding other species of chameleons, the team spent several days above the Sanje waterfall at an altitude of approximately seven hundred meters. Several tours of discovery even higher after the Chamaeleo were unsuccessful.

The expedition was coming to an end and the Exo Terra team still had to descend to the road that would bring them back to Mikumi and on to Dar Es Salaam. The descent is an incredibly beautiful hike with a spectacular view of the waterfall. The team camped at the top of this waterfall for several days.

Shortly before arriving in the village, a smooth-edged jointed turtle crossed the path in front of us. The genus Kinixys is unique in the turtle world because of its hinged armor. The hinge allows the turtle to fold down the back of the shell to protect itself from predators.

The Exo Terra team can look back on a very successful expedition. Again and now for the third time a new species has been discovered. Many animals in this film were filmed the first time in their natural environment. This grants unique insights into their ecology and behavior. The expedition is sure to add to a better understanding of Tanzania's remarkable and spectacular herpetofauna.