The genus Atheris, currently comprises fifteen species of small, heavily keel scaled, arboreal pit vipers. The vipers are distributed in sub Saharan African and are typically encountered in primary forest, cloud forest and disturbed forest edges. Some of the species of Atheris are very prominent in the hobby, whilst some are totally unavailable. For this article I will cover the species available to the hobbyist. Firstly the “highland “ forms:
Atheris ceratophora -The Usambara Bush Viper
Once common in the hobby, this species is now extremely hard to legally acquire due to the export restrictions on reptiles from Tanzania. Captive bred specimens fetch an extremely high price.
Identification: This iconic viper is easily identifiable by its triangular head, covered in keeled scales which form a cluster of “horns” above each eye. This tiny viper may reach 55cm, but most often the adult size is around 40cm. The colouration is extremely variable, often yellow with black speckling, but may be green, yellow, orange, black or even brownish. Neonates are dark brown or black until they have had multiple sheds. The tail is noticeably prehensile and lighter coloured.
Distribution: Atheris ceratophora is a species endemic to Tanzania. It is found from low to medium elevations and is known to inhabit forest areas at over 2000m. Atheris ceratophora is found in the Usambara, Nguru, Uluguru, and Udzungwa mountains.
Habitat: Often encountered in low bushes, as in all Atheris, this species is primarily arboreal. They can however be encountered on the forest floor when hunting. Ceratophora will remain sedentary for long periods of time, sitting in ambush position, The diet of this species is predominantly amphibians, however reptiles and small mammals may also be taken.
Breeding takes place in September to October, with neonates commonly encountered from March to May. As this is a montane species, night time temps are consistently low, with winter day temps as low as 6 degrees Celsius. During this time the snakes will enter a dormant period, not feeding or moving.
Venom: The venom of Atheris ceratophora contains procoagulants and hemorrhagins. The relatively low LD50 rating and small amount of venom delivered means bites from this species are potentially, but unlikely to be fatal.
Atheris Matildea – Matilda’s Bush Viper
This species is a new species to the Atheris genus, being discovered in 2011. However many matildae exist in the hobby after being imported as Atheris ceratophora. Like ceratophora, wild caught specimens of this species are no longer legally available.
Identification: Superficially identical to Atheris ceratophora, however this species grows much larger, with adults reaching over 60 cm.
Distribution: Southern highlands of Tanzania.
Habitat: Matildae is a viper of montane forest habitat. The distribution of this species has been withheld to prevent collecting for the pet trade.This is a montane species, used to great temperature fluctuations, with high day temps, and night temps as low as 6 degrees Celsius.
Venom: The venom of Atheris matildae contains procoagulants and hemorrhagins. The relatively low LD50 rating and small amount of venom delivered means bites from this species are potentially, but unlikely to be fatal.
Atheris desaixi – Mount Kenya Bush Viper
This species is occasionally available to the hobbyist, predominantly as wild caught imports. Their rarity in the hobby ensures available specimens command a high price.
Identification: Atheris desaixi is a large bodied viper, with a distinct triangular head. This species can reach 70 cm in length. A beautifully marked snake, with a background colour of green, yellow and black with light scale tipping, giving a bobbled appearance.
Distribution: This species is endemic to the Southern Highlands of Kenya, with distinct populations in Nyambene, Northern Nyambene ranges and Mount Kenya itself.
Habitat: Typically arboreal, being found in primary forest and forest edges along cultivated land. Usually encountered sitting in bushes at around 2 – 3 m above ground. This species feeds on amphibians, reptiles and birds.
Venom: The venom of Atheris desaxi contains procoagulants and hemorrhagins. This species has a large head and large venom glands, bites from this species are potentially fatal.
Atheris nitshei – Great Lakes Bush Viper
A favourite amongst venomous keepers, this species is regularly captive bred in Europe but still commands a high price.
Identification: This is a large but slender viper, attaining lengths of over 70 cm. The snake is a vivid green, with a distinct black broken zig zag pattern. The underside is pale green to yellow. The tail tip is pale, and may be used for caudal luring.
Distribution: The range of this species spans from the Democratic Republic of Congo, to Rwanda, Burundi, Tanzania and Uganda.
Habitat/Natural history: This species is a montane wetland specialist, and is always associated with water bodies of some description. Commonly found at altitudes of 1,600–2,800 m. It is common in reeds and papyrus bushes, where it will hunt along water courses for amphibians. Nitschei are known to eat variety of amphibians and reptiles, notably Jacksons forest lizards and chameleons. Breeding takes place from April to May with females giving birth from October to November.
Venom: The venom of Atheris nitschei contains procoagulants and hemorrhagins. The relatively low LD50 rating and small amount of venom delivered means bites from this species are potentially, but unlikely to be fatal.
And now the “lowland species”
Atheris Squamigera – Variable Bush Viper
Atheris squamigera or squams as they are commonly known are one of the most popular hots in the hobby. The ease of care, sedentary habits and huge colour variation make them ideal captive specimens.
Identification: Atheris squamigera grows to an average total length of 46 to 60 cm, with a maximum total length that sometimes exceeds 78 cm Females are usually larger than males. The head is broad and triangular and covered with keeled, imbricate scales. The dorsal colour varies from sage, dark green, bluish, olive or dark olive brown, orange, yellow, reddish, orange slate gray or the most highly prized black. The scales have light coloured keels and sometimes yellow tips that form a series of 30 or more light crossbars. Neonates have a dark, olive coloration with some barring, however the adult colour pattern develops within 3 to 4 months.
Distribution: Atheris squamigera is found in west and central Africa, the Ivory coast, Ghana, eastward through southern Nigeria to Cameroon, southern Central African Republic, Gabon, Congo and Democratic Republic of Congo, Angola, Uganda and Tanzania.
Habitat/ Natural history: Atheris squamigera occurs primarily in tropical forests and areas with dense vegetation where small reptiles and other prey animals are abundant. This species is most commonly found at elevations ranging from 100 to 400 m in elevation. A. squamigera occurs most often at lower elevations, which tends to support greater vegetation densities. In general, this species resides in moist, terrestrial, and arboreal habitats throughout its geographic range.
Breeding takes place from April to May with females giving birth from October to November.
Venom: Bites from this species have resulted in at least one report of severe hematological complications, as well as two deaths. Although no specific anti-venom is made for the genus Atheris, anti-venom for the genus Echis, the saw scale viper, has been shown to be partially effective in neutralizing Atheris venom
Atheris Broadleyi – Broadley’s Bush Viper
Split from Atheris squamigera in 1999, the Broadley’s Bush Viper is extremely popular in the hobby, particularly in Europe, the ease of availability of wild caught specimens coupled with the stunning colouration ensures their place in many collections.
Distribution: Cameroon, Central African Republic.
Description: Superficially Atheris broadleyi resemble Atheris squamigera, however scale counts differ. There is also a pale stripe behind the eye. The huge colour variation of squamigera is not seen in Broadleyi, with specimens being mainly green, green and yellow or bronze.
Habitat/ Natural history: broadleyi are a forest dwelling species often encountered at forest edges. Their natural history is the same as Atheris squamigera.
Venom: Hemotoxic. Similar to the venom of squamigera.
Atheris Chlorechis – Western Bush Viper
The vivid green colour and the ease of attaining wild caught specimens make these very popular in the hobby.
Distribution: Ghana, Guinea Bissau, Guinea, Sierra Leone, Ivory coast, Togo, Benin.
Description: Adults average 50 cm in total length with a maximum total length of 70 cm. Adults have a uniform light green ground colour, overlaid with a series of faint yellow, roughly paired spots running dorsally along the length of the body. Neonates are dark in colour, but this changes to a yellow-green hue with irregular dark spots after the first shed.
Habitat/ natural history: Similar to Atheris squamigera, found in bushes, forested areas, often a few meters off the ground in ambush positions. Atheris chlorechis feeds on reptiles, amphibians and small mammals.
Venom: Similar to Atheris squamigera. Hemotoxic components. Potentially life threatening.
Captive Care of Highland Atheris
Firstly let us consider that Atheris species, although relatively small, are still venomous and potentially life threatening. Atheris species have caused fatalities in the past and are entirely likely to cause an allergic reaction. Fatalities aside, envenomation will still be painful, with a wide range of systemic symptoms including swelling , nausea and necrosis. As with all venomous species a period of mentoring is recommended before keeping personally. Please ensure your State or County allows the keeping of venomous animals.
The highland Atheris are in my experience are very sensitive to prolonged periods of high temperatures, and as such are not suitable to be kept in a snake room with species that require high stable temperatures. Lowland Atheris species are more tolerant and can be kept in a building with a higher ambient temperature. Mine seem to do well in the mid-range of 80-84 degree F day time highs, with a small night drop.
I keep my Atheris individually in medium arboreal Exoterra vivariums. I find these vivariums allow good airflow and are easy to maintain. I use an eco earth substrate, seeded with arthropods. The vivs are furnished with numerous branches and a mixture of live and plastic plants.
Lighting is on a 12 hour cycle, with a natural dawn from the window, followed by lights on until just before dusk. A natural dusk will occur after lights out. As far as light for each viv, I use a jungle dawn to promote plant growth and an Arcadia Pro UV kit on each viv. Although this genus are predominantly nocturnal, my animals are often out basking under the UV in the daytime. Be mindful that your lighting does not raise the temperature in the viv too much.
Regarding temperatures, for the montane species I would recommend a day time temperature no higher than 82 degrees, with a significant night time drop. As such, I do not heat my highland Atheris, the lighting provides a hot basking spot, and the ambient room temperature stays around 80 degrees in the daytime. At night with lights off, the temps drop to around 70 degrees in summer and 65 in winter. I have had no health issues with these temps, the snakes look extremely healthy and breeding has occurred.
Humidity is also an important factor, the highland species occur in a relatively humid environment and as such a background humidity of 60 – 75 is ideal. I spray in the morning as lights come on, and again just prior to lights being switched off. Good air flow is important to prevent bacterial growth, ensure the substrate dries out between sprays to prevent water logging. Atheris will drink from water bowls, but seem to prefer drinking away from the ground , so raised water containers and daily spraying of vegetation are best. For the lowland species, I spray once a day before lights out, and ensure the substrate does not become waterlogged. The lowland species will require a “dry period” with no spraying for a few months, obviously with access to a water bowl. Constant high humidity is detrimental to lowland species health.
Feeding both highland and lowland Atheris is normally straight forward. In my experience most adults will readily take frozen thawed mice of appropriate size, however I try not over feed with mammal prey as it is not a massive part of the natural diet of this genus. Atheris has evolved to predominantly feed on reptiles and amphibians, occasionally invertebrates and birds. With all snakes in my collection I try to mimic the natural diet as much as possible. I use house geckos, frogs legs and day old quail. A lot of Atheris keepers also use earthworms. I feed every three weeks or so, Atheris have a good prey response and easily become obese, leading to health and breeding problems.
Breeding is down to prey, light, temperature and humidity cycling, in my opinion. I place males into the female vivariums at the end of March, the temps have been progressively lowered from November, then raised slightly at the beginning of March, feedings have been bi monthly in August and September, then once a month in October and November, ceasing in December. The female is fed prior to the male being placed in her vivarium. This genus may exhibit cannibalism.
Neonates are born live around October and are minute.. the neos are hard to get started feeding, and I find mourning geckos are ideal to kick start an interest in food. If necessary assist feeding with pinky parts can be undertaken. They are set up in Exoterra Nanos. Light, heat and humidity parameters are the same as for adults. The neonates are particularly sensitive to low humidity and high temps.
I am not saying everyone should keep their Atheris in this way, but this method has worked over the years for me. Atheris are beautiful, interesting , hardy and reproductive hots, I would recommend anyone that is building a venomous collection consider this genus.
Disclaimer: Nothing written in Herpetoculture Magazine or on this website is encouraging or convincing the reader to act in any manner or to perform any action with any venomous species. You as the reader are fully responsible for your actions taken as a result of reading the information provided here.
