The Mantella FAQ
by Marc S Staniszewski

[image]
Golden Mantella (Mantella aurantiaca)


INDEX

* Not a valid name but used here for identification purposes and may be named in the future

LITERATURE CITED

INTRODUCTION

The Madagascan Ranidae (typical frog) subfamily mantellinae consists of two genera. The larger but least familiar is the diverse genus Mantidactylus consisting of over 40 species of ground dwelling, scansorial and arboreal frogs. The small yet infinitely more popular is the beautiful genus Mantella which consists of 11 definite species, several unconfirmed 'species' and a host of subspecies and geographical forms. Mantella's are currently ranked behind poison dart frogs (Dendrobatids), horned frogs (Ceratophrys), clawed frogs (Xenopus) and axolotls (Ambystoma mexicanum), in terms of terrarium popularity. This in itself has imposed a serious problem on the already dwindling native populations of these frogs in their natural habitat. Overcollection, the introduction of predatory 'supertramp' animals, serious deforestation and human encroachment (the all too familiar buzz words of our age) has resulted in some species declining to the point of near extinction.
Like the unrelated dendrobatids of the new world, their aposematic (warning) colours exhibit combinations of inky blacks and dazzling iridescent blues, oranges, yellows and emeralds reflecting the toxic nature of their skins. They are almost entirely terrestrial in habits (two species are scansorial) with eggs being laid in damp hollows always out of water. They are very small in size, have complicated courtship rituals and are almost entirely active by daylight. Several species are non-poisonous and are said to show Batesian or protective mimicry - imitating the colours of truly toxic species. Mantella's are confined to Madagascar and a few neighbouring off-shore islands.



ACQUISITION & INITIAL CARE

Mantellas are only likely to be seen on specialist herptile suppliers lists, private adverts in herptile association newsletters or at herptile sales/exhibitions. Therefore actually viewing a specimen before acquiring it is likely only in the last case. Like many other amphibians, if they are properly packaged for transportation they will not suffer undue stress. Proper packaging is a plastic container loosely filled with damp sphagnum moss into which they will burrow, the container must be well ventilated and the frogs should travel at a temperature in the 65 - 74F. range. Unfortunately many mantellas are not distributed in this simple way. A bruised, languid, dehydrated or dead mantella is an unnecessary yet all-to-common sight particularly in wild-collected specimens. This is the single reason why, unless the dealer is a reputable one, wherever possible these frogs should always be viewed prior to purchase. Otherwise you are taking a potentially expensive risk. Mantella's should always be given a short 'quarantine'. Introducing even a seemingly healthy mantella into an existing and healthy colony is a recipe for disaster. They could communicate infections such as the notorious Aeromonas 'red leg' syndrome or internal parasites. Always make absolutely certain that new mantellas are as healthy as possible before introduction to a colony. Mantellas are as a rule territorial and if the new introduction is not physically strong its health will quickly recede due to bullying from other mantellas.
Another aspect to consider when purchasing mantellas, particularly where there is an intention to induce captive breeding, is the sex ratio. In the wild, male mantellas of most species outnumber females by approximately two to one or higher. Therefore as a yardstick aim to purchase two or three males for every female. This will not only encourage the territorial behaviour but also a more vigorous pairing (see breeding section for sexual dimorphism pointers and reproductive behaviour). However it is not impossible to breed mantellas with just one of each sex, its is just that you stand more chance with more males.

 

 
HOUSING

Containers
Regardless of their size, mantellas require relatively spacious housing. This is due mainly to the fact that both sexes (but especially males) patrol small territories. Too small a container results in excessive contact and stress. Too large a container results in very little contact and no successful pairing. Start at a 60cm x 30cm x 30cm for 3 or 4 individuals and work up to a maximum of 90cm x 40cm x 50cm for 10 to 12 mantellas.
Types of container do not matter even for nervy species such as Mantella pulchra. An aquarium can be simply but effectively modified by affixing suitable background scenes to the side and back panels. However even for bold species such as the golden mantella I would recommend a custom built wooden vivarium with a glass front mainly because it prevents limb and snout injuries, and heat/humidity control is easier. I like to have 10cm deep glass trays (constructed by my local tropical fish shop) fitted neatly into the bottom of the wooden vivarium. These are easily removed to allow cleaning. Front sliding or hinged glass doors are entirely up to the hobbyist but whichever door or container is used, it must be made escape-proof because I have no hesitation in proclaiming mantellas expert escapists squeezing through the smallest of gaps. Mantellas too expensive and too rare a frog to lose in such a manner. Ventilation is extremely important in mantella set-up. As these frogs excrete large amounts of waste in the form of small droppings, along with the constantly humid conditions required, this equals a paradise for mould and fungi. Simply closing up the container to increase humidity is a bad move as the frogs will quickly succumb to bacterial infection.
The layout itself need not be too complicated. Considering the fact that the whole vivarium will need cleaning out every 5 - 8 days, a hobbyist can spend large amounts of time cleaning therefore it is wise to keep it simple. For a natural layout use a nice spongy sphagnum or java moss base on top of which are laid several decorative pieces of bogwood, rocks and branches. A shallow - 2cm deep - 10cm diameter water pan should be placed to the side furthest away from the light and under- vivarium heater pad source as this allows for a cool retreat in case of overheated mantellas. A few creeping house plants such as snakeskin plant (Fittonia), ivy (Hedera and Helix) and bottle ferns can be left in their pots which are concealed with moss but remember that daylight emitting lighting is required for their survival. Otherwise imitation plants (which often appear like the real thing in any case) are equally suitable.
In my own opinion the synthetic material which retains moisture is significantly advantageous especially where large numbers of mantellas are concerned. Synthetic rubber foam used in upholstery is excellent and should be soaked in water then gently squeezed so that it is uniformly moist. A hole can be cut out for the water pan to be sunk in and bog/driftwood, rocks, barks and leaves of imitation plants can be scattered across the top so it really does look like the natural Madagascan forest floor.


Lighting & Heating
As mantellas are predominantly diurnal, correct photoperiod plays a decisive part in behavioural and reproductive regimes. I have had success with both simple tungsten lighting and full spectrum fluorescent lighting. As these frogs come from the southern hemisphere island of Madagascar, the hours of daylight varies a lot less through the seasons than northern Europe and the seasons are different. I have found few problems in coaxing wild-caught mantellas to adjust our seasons in the UK while captive-bred mantellas present no difficulties whatsoever. The photoperiod however should be 10 - 11 hours during winter and 12 - 14 during summer.
Heating is a much overlooked aspect of mantella care. Many hobbyists presume that because mantellas come from a large island in the Indian Ocean they require tropical conditions. In fact for many species the complete opposite is true because they often inhabit cool montane cloud forests. The only species that demand a true tropical environment are the mainly coastal lowland inhabitants Mantella expectata, Mantella betsileo and Mantella bernhardi. The rest dislike high temperatures, indeed the golden mantella only occurs above 900m where conditions are not unlike those experienced after a rainstorm during a British summer - cool and humid.
To achieve the optimum temperatures for each species (see 'species section') I prefer to use an under-vivarium heater pad which covers approximately half of the vivarium base itself. This is connected to a an adjustable thermostat, the sensor of which is raised just off the base of the vivarium substrate (ie. the moss or foam). If used with fluorescent lighting which emit little heat, optimum temperatures can be accurately provided to within 2 or 3C.
Also remember at night that all mantellas naturally experience a drop in temperature by 5 - 15C. and this should be reflected in captivity.


Hygiene
The final aspect of housing involves hygiene. As previously stated mantellas can be quite messy for such a small creature and are rather indiscriminate where discharging their dropping is concerned. Over the course of a week, if they are properly fed, large amounts of waste are excreted, which under humid conditions quickly become blanketed in fungi and mould. The water source will also become fouled and this is best changed every 2 - 3 days. To prevent too high a build up of bacteria and fungus it is wise to thoroughly clean out the vivarium, aquarium or glass tray every 5 - 8 days, soaking imitation plants, bogwood, rocks and bark in boiling water (making sure no mantellas are still hiding unseen in any nooks and crannies!) for ten minutes, swilling or replacing moss and wiping down live plants with a damp cloth. Then wash the glass aquarium or tray with a 'safe' anti-bacterial cleaner such as Dettox making sure it is thoroughly swilled out after, or wipe down the insides of the wooden vivarium. To many hobbyists, me included, this can seen like a laborious task, but going to this much trouble is essential in the successful maintenance of mantellas.


FEEDING

Variety is the essential. Being entirely insectivorous, offer as wide a range of small invertebrates as possible to provide a balanced diet. Some species such as the little- known Mantella haraldmeieri are notoriously fussy preferring only termites (although I managed to coax this species into taking small black field crickets which looked like the termites). Other species such as the golden mantella will attempt to eat anything even if they dislike its taste. Crickets are the obvious year round source of food but to make these more nutritious, the crickets should be a given a crumbly mixture of bran, finely chopped lettuce and a multivitamin supplement such as cricket-diet. Don't however feed solely crickets to your mantellas. Vary it by offering fruit-flies, lesser waxworm, small house-flies, spiders, caterpillars, small beetles, moths and sweepings. During summer aphids/greenfly/blackfly/whitefly and cabbage fly are all avidly taken by most species but make sure these have not come into contact with pesticides. Avoid foods such as mealworm which mantellas find difficult to digest (although freshly sloughed small mealworm are okay as an occasional treat).
Feeding frequency is equally as important as variety. In the wild mantellas spend most of their day hunting. In captivity offer several small sittings per day rather than a single large one - morning, late afternoon and just prior to lights-off for example. Also beware of overfeeding mantellas. Golden, yellow and green mantellas in particular are very greedy.

 


BREEDING

Sexing
Sexing mantella's can prove tricky in some species. Generally, adult male mantellas tend to be smaller and less rotund than the adult female, sometimes more brightly coloured, the skin around the throat is often loose caused by vocalizing and femoral glands are either larger or more distinct (these are the pair of oblong pads located either side of the vent). Obviously less mature female could be confused with an adult male and there is no hard rule in sexual dimorphism where this is the case.
The golden mantella group (aurantiaca-'milotympanum'-crocea) are more easily sexed by observing the ventral surface. These frogs possess lighter coloured ventral surfaces in males through which a narrow pair of pale lines called seminiferous ducts are visible. Such ducts actually have a dual purpose ducts by carrying both sperm and urine (and can therefore also be called ureters). In females although the ureters are in the same position, they are largely concealed by the uterus and oviduct. One final determination method applicable to Mantella bernhardi and Mantella haraldmeieri is the extension of the pale horseshoe marking on the throat. In males this extends to the back of the throat while in females it exists simply as a white band.


Stimuli
Once a sexed pair or a colony has been established then it is a case of waiting for them to settle down. Provided conditions are favourable (although not necessarily perfect), males will become increasingly territorial (as will females to a lesser extent) and vocalization will begin. Perhaps two of the most unexpected mantella species represent the loudest callers. Mantella bernhardi is one of the smallest mantellas yet it is by far the most vocal emitting a shrill whistle sound that is varied in frequency and noise level depending on how excited it is. Mantella 'milotympanum' is the most reticent, nervy and smallest of the mantellas yet males will call loudly from their secretive retreats with a slow, low pitch click for hours on end! Conversely the male of boldest species - Mantella aurantiaca - is often quite reluctant to call. If male mantellas of any species seem reluctant to vocalize then ensure that a wide variety of food is made available and cool mistings of the vivarium on warm days are frequently conducted. Territorial aggression is commonplace in both sexes but especially males. Intruders are likely to be grabbed around the head or upper body and assertively pushed away.
Actual courtship of the two sexes is a rather secretive affair transpiring under bark, logs or rocks although the typical grasping behaviour loosely termed amplexus can sometimes be viewed especially after misting. If the female is not gravid then after repeated flicks and back-flips the male will eventually release her.


Egg-Deposition & Initial Care


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Mantella aurantiaca eggs deposited in a hole drilled
in a piece of bogwood after 4 days developmen
t

Once in a successful union the female will then begin to search for a suitable egg-laying place. Eggs are never laid directly in water and therefore should not be transfered to an aquarium or water dish. A suitable egg-laying site is almost always somewhere moist and enclosed; depressions in sponge, moss or tissue paper, holes or crevices in logs, gaps at the side of water pans and beneath damp rocks or bark. Egg deposition almost always ensues during nighttime and unless you are prepared to keep a twenty- four hour vigil you will miss the event. The relatively large eggs are encased in a clear gelatinous shell the nucleus of which is usually pale in colour and measures 2 - 3mm in diameter. Numbers of eggs varies with species and age of female with a mature female Mantella aurantiaca able to produce in excess of 100 eggs while the diminutive Mantella 'milotympanum' barely reaches the 20 mark. Eggs can be fertilized either immediately on deposition or up two days after and by several males. Unfortunately a common occurrence in captivity is the high incidence of infertile eggs caused simply by lack of male interaction. You can usually tell that a batch of eggs is not going to be fertile either because there is no sign of embryo development within 18 - 30 hours, or the nucleus starts to shrivel and eventually mould over. If eggs are successfully fertilized they will absorb lots of water and expand accordingly.


Mantella aurantiaca
Male Mantella aurantiaca 'guarding' eggs

Eggs are best left in situ until the well-formed tadpoles are ready to hatch out which is usually after the 2 - 6 day mark. Mist them regularly to ensure they do not dry out. Hatching is a critical time in the development. Somehow the eggs need to be submersed in water so that tadpoles can wriggle free. However where eggs are situated in holes or crevice or they are adhered to the underside of rocks or bark they can be difficult to remove manually without crushing the tadpoles themselves. If this is the case either remove the entire log, rock etc. and submerse in water, or remove adult mantellas and begin to fill up the aquarium or glass tray.


Tadpole & Froglet Care

Water must be maintained within a relatively small temperature range otherwise tadpoles will quickly succumb. I have found that for lowland species (ie. M.bernhardi, M.betsileo, M.expectata, M.laevigata, some M.baroni and M.viridis) tadpoles require a temperature in the 70 - 78F. range, while highland species (all other species not mentioned above) 65 - 74F. is necessary. Although this allows for proper metabolism and good growth, in addition the water quality is just as important. Depending on species, mantella tadpoles metamorphose after 45 - 360 days. During this period they will excrete large amounts of waste which must be removed. Therefore filtrate/aerate the water freely with one of the small semi-submersible pumps now available (although I would recommend gentle aeration for the first 14 - 20 days of development). Water depth can start off at about 2 inches and should comprise of a gravelled bottom with some rocks and a few bunches of Hygrophilia polysperma and eel grass (Vallisnera spiralis). The water itself should consist of pre-boiled 60% rainwater and 40% tap water that has stood for 24 hours. pH (alkalinity) is not critical but it should be in the 6.0 - 7.5 range to be safe (ie. slightly acidic). As tadpoles develop so the water should be gradually raised to about 10cm in depth. 30% partial water changes should be carried out every 2 days and any dead tadpoles must be removed as soon as possible.


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Mantella aurantiaca tadpoles - lower tadpole is 43 days old
upper tadpole is 21 days old

Expect approximately a 50% mortality rate even under seemingly crystalline water conditions. Mantella tadpoles are largely herbivorous filter feeders nibbling on algal and vegetable matter but also benefit from the occasional chunk of raw red meat dipped into the water for a day or so. Fish flakes and trout pellets are also relished. Hind limbs appear 18 - 280 days after the tadpoles hatch while the forelimbs and the general mantelline shapes appears a further 25 - 80 days later. Tail absorption is a critical time for the emerging froglets because they can easily drown. Easily accessible land areas composed of gently sloping, moss-blanketed rocks are essential and once the 5 - 10mm froglets are seen crawling on to these they must be removed to individual moss filled plastic containers.
As froglets are so small they are only able to devour sweepings such as springtails and small aphids (even fruitfly are too big). Further losses must be expected at this stage even where food is in abundance and 30 - 50% of the original clutch of eggs is considered a success. After 10 - 12 weeks vivid colours begin to show though and froglets will be about 10 - 14mm in length. Maturity is attained within 12 - 14 months.

Longevity of many mantellas is still unknown mainly because they have not been studied enough. Golden mantella's can attain 8 years but as this is a highland species with a relatively low metabolism, lowland species may have a shorter lifespan.


HEALTH & DISEASE

Practising good terrarium hygiene at all times will go a long way to ensuring that specimens remain in tip-top condition. The only likely occurrence of ailments is either when mantellas are first acquired, through mechanical injuries in easily stressed species or when kept under incorrect conditions.
Malnutrition is unfortunately quite common in wild-caught mantellas which may be in transit for several weeks without food. During this time disease is most likely to strike and therefore an initial quarantine period is important. Initially starved mantellas are dull in appearance and lethargic, often refusing food for the first few days. I know from experience that if warm, humid and shady conditions are provided they'll soon settle down and begin to eat. Liberally dust all foods in a multivitamin powder at this time. If newly acquired mantellas still refuse food after a few days then bathe them several times daily in a shallow dish of luke warm water enriched with a combined multivitamin/mineral solution. This will be absorbed through the skin and can trigger the feeding behaviour.
Mantella's are of a
nervous disposition (especially M.pulchra and M.'milotympanum'. They may attempt to leap through the clear glass of an aquarium or glass front of a wooden terrarium sometimes sustaining injuries. These would heal under normal conditions, however if such behaviour persists the wounds can become progressively worse and infected. Treatment is with an effective tropical fish bactericide such as a BSB (Broad Spectrum Bactericide) by dissolving 4 - 5 drops in a pint of water and applying to the wound with a swab of soft cotton wool several times a day. Frogs can even be bathed in the solution for 5 - 10 minutes twice a day where infection is particularly bad. The best method is preventative medicine, ie. blocking off the glass when the mantellas are not being viewed at least until they settle down in captivity.
Bearing in mind their small size, treatment for external/internal
pathogens that rare occur in these frogs can prove very difficult. I have found in the past that simply applying those preparations sold for tropical fish at 1 - 2 times the strength recommended for fish and bathing the specimen in this for 5 - 10 minutes twice daily can prove successful. The only other biological disease to affect mantella's is 'red leg' caused by the bacteria Aeromonas hydrophilia. This can be difficult to detect in its early stages because the femoral glands around the cloaca and the orange/red thigh markings on many species may be mistaken for the characteristic suffusion of red or orange caused by this disease. Use a magnifying glass to closely study the 'affected' area. A tiny network of ruptured capillaries spread across the surface of the thighs and ventral surface will be evident if red leg is rife. Fortunately red leg is extremely rare in mantellas. Treatment involves bathing the whole body of the frog in a 1% solution of copper sulphate (sometimes in the form of the safer 'chelated copper' products used by tropical fish hobbyists) or a 5% topical application of the antibiotic baytril.
Perhaps the most common ailment is
HRMSS or  'heat-related-muscle-spasm-syndrome'. I have witnessed this in the golden, green, Malagasy and Cowan's mantella's and is caused by prolonged exposure to high temperatures that such species never encounter naturally. Occasional fluctuations to 80 or 90F. seem to have no adverse affect, but if such temperatures persist for 3 or 4 days then the mantellas start exhibiting a flicking of the hind limbs almost as if they are attempting to remove irritant parasites. It is actually caused by contraction of the muscle tissue caused by heat. Eventually the whole frog's body stiffens, hind limbs become paralysed and the frog dies what appears to be a very painful death. The effects are catastrophic and even if the mantella's are relocated to cooler conditions, unfortunately this syndrome has a 70 and 90% mortality rate depending on species. Again prevention is the word. I installed AC at great cost to prevent such things happening after I lost a colony of goldens. Fortunately the tadpoles from that colony were unaffected and now form the basis of my new colony.



THE SPECIES

For descriptive purposes the mantellas can be split up into four groups;


THE YELLOW MANTELLA GROUP

Golden mantella (Mantella aurantiaca)

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Red Mantella aurantiaca the beautiful orange-red form
from the Anosibe An'Ala Forest, Madagascar

20 - 26mm. Occurs in several colour forms, each confined to very small locations within the eastern quadrant of Madagascar. It had recently been denoted as a CITES appendix II species. The type orange form is located in the montane Pandanus forests around Andasibe, the pale orange/yellow form in Baparasay and the deep blood orange form in the forests of Anosibe An'Ala. All occur above 900m and therefore conditions must be replicated in captivity accordingly (ie. temperatures no higher than 78F., preferably around 68 - 70F., high humidity and quite open, light conditions). This species is very showy in captivity preferring elevated positions out in the open. Males are generally smaller, slimmer and more angular in build than females and not as vociferous as other mantella's. Alternatively sexes can easily be determined through the ventral surface method. Once it has settled down it is one of the easiest species to breed in captivity although unsuccessful fertilization of the eggs is sadly quite a common occurrence. Females can produce eggs at a rate of once every two months given proper care.


The black-eared mantella (Mantella cf. aurantiaca 'milotympanum')

Mantella 'milotympanum'
Mantella 'milotympanum' is very different
in both appearance and behaviour from M.aurantiaca

15 - 18mm So different in appearance and behaviour to M.aurantiaca that it must merit being raised to specific status. Occurring in the Fiherenana Valley in central east Madagascar it requires slightly higher temperatures (70F. minimum) than the golden mantella. Its size makes it the smallest subspecies/species of the mantellas. The dorsum is a slightly drab orange (males brighter than females) while the venter is a greenish yellow (orange yellow in M.aurantiaca). This species is overall much slimmer than the golden mantella, the eyes are oblong rather than round and the skin is much more granular. Raised veins are apparent on the hind limbs, as its name suggests the eardrum (tympanum) is black as is the nostril region and there is a black line apparent from the eye to the nostril. Perhaps most significantly is its very nervous disposition and semi-nocturnal behaviour. In addition males are amongst the most vociferous of the mantellas and will call for many hours. I have just had a spawning from the species and the eggs are quite different from the golden mantella possessing a yellowish-brown nucleus and measuring only 1mm in diameter.

 

The yellow mantella (Mantella crocea)

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Mantella crocea is perhaps the ideal
species for the beginner and settles well in captivity

22 - 25mm. The ideal beginner species. Occurring at altitudes of 500 - 1000m around Andasibe and Moramanga, eastern Madagascar. Tolerant of temperatures as low as 62F. and present no difficulties where feeding is concerned. Like the golden mantella it is a bold species and males will often perch on the highest available point and call excitedly. The dorsum is usually a greenish orange with black flanks and speckled lower back regions. A beautiful lemon yellow form exists (from which this species gets its name) which is much plumper and slightly larger (to 28mm) than the type normally occurring in the hobby. The ventral surface is blue-black in the green-orange form and pale orange in the yellow form, the sexes of the latter being able to be determined by the ventral method. The eggs are an off-brown colour and about 2mm in diameter, up to 50 being produced per clutch.



THE COASTAL MANTELLA GROUP
Species of this group do not occur regularly in captivity. There appears to be no real reason for this except that most have rather small distributions.

Brown mantella (Mantella betsileo)
25 - 28mm. Quite an attractive species that is found in small pockets from the central to the north of the island. Quite a large plump species attaining 28mm the dorsum is a light tan while the flanks are black with white/blue reticulation. The venter is blue and white-grey speckled. In captivity it is quite shy preferring a good spread of bark, pebbles and leaves beneath which is will skulk. Sexing presents difficulties as both sexes are very similar. Look as the vent region and you will see well-developed orange femoral pads in males which are much reduced in females. Although there are records of the occasional captive breeding success, this species is not often kept in captivity and therefore details are sketchy.

 

Green mantella (Mantella viridis)

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Mantella viridis is the largest species from a few very
restricted localities on the northern tip of Madagascar

28 - 35mm. The largest species described so far. Only described in 1988 from specimens discovered in a small part of the Montagne de Francais region of the extreme north tip of Madagascar. Two colour forms exist, the most typical being a grey-green colour with dark flanks and stippled hind limbs. The other is a smaller, gorgeous lime green form (potentially a different species!) with well-defined black flanks. Both types have a white band around the top lip and venter coloured in black and blue speckles. Females tend to be larger, more plump and have a rather squarer snout. In captivity although it is an easy species to maintain, it is quite reluctant to breed. It certainly will not breed where mantella of other species are present. I have found the a frequently misted vivarium with plenty of low growing plants (live or artificial) along with plenty of damp logs and bark is preferred. It also enjoys bathing. Temperatures need to be in the 72 - 78F. range with a slight drop to 68F. at night.

 

Blue-legged mantella (Mantella expectata)

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Mantella expectata is a beautiful stocky species from the
dry south west baobab forests of south west Madagascar

20 - 30mm. Discovered on the edges of a brook in the drier regions of southwestern Madagascar as recently as 1993. Further exploration revealed small pockets of this frogs along most brooks in the baobab forests of that region. The colours vary quite considerably but the most prized are those with a bright yellow back and stunning blue flanks and limbs. Such frogs, although not rare, appear less frequently than those with slate-grey or brown limbs and a rather green dorsum. Females much larger than males. In captivity it requires a fairly extensive but shallow body of water around which are positioned pebbles and rocks with a scattering of leaves (imitation are quite suitable). The vivarium should be misted less frequently than for other species during most of the year. Although males call continuously, to stimulate these frogs to reach reproductive condition, during late spring to late summer mistings should be more protracted and frequent. It seems that in the wild the brief rainfalls of that region is the stimulus and females will then produce 2 - 6 clutches off 35 or more eggs (one of my own females has just deposited 52 small yellowish eggs which unfortunately have not been fertilized).

 

 

THE VARIEGATED MANTELLA GROUP
This group consist of some of the most beautiful of the mantellas and also some of the most confusing in terms of taxonomy.

Cowan's mantella (Mantella cowanii)

[image]
Mantella cowanii was, until recently, thought
to be a colour variant of Mantella baroni

22 - 30mm. Patterned largely in black with orange or red bands around the limbs. This species is much shyer athan the closely related M.baroni and rarely ventures from the preferred humid, leafy base of the vivarium apart from the odd bold male specimen in search of a female. Males are quite vocal , the call being reminiscent of a slower crickets chirrup. Breeding is quite a frequent occurrence in captivity with 40 or so eggs being nestled in damp leaves or moss. Temperature-wise it prefers slightly higher than that described for the golden mantella although it is quite tolerant of low temperatures as long as there is sufficient cover.

 

Painted or Malagasy mantella (M.baroni)

[image]
Mantella baroni is very common in the hobby but beware
that this species reacts infavourably to high temperatures

28 - 32mm. Extremely variable in range and behaviour occurring over much of the eastern half of Madagascar. Coloration ranges from a general black dorsum with vibrant yellows, greens and oranges to almost completely melanistic specimens. The distinguishing feature is the light rostral line above the eyes and the tiger-like markings on the hind limbs. It is the largest species after the green mantella. Requires a roomy vivarium with plenty of elevated areas which the energetic males will guard. Many specimens imported as M.cowanii are in fact this species. Occurs at altitude and in the lowlands so it may be worth experimenting with temperatures and set-up if a specimen reacts indifferently or refuses to breed. The skin of this species is known to contain alkaloid derivatives similar to those of the neotropic poison dart frogs and therefore the coloration is said to be aposematic. Always handle with care where necessary.

 

Parker's mantella (Mantella pulchra)

[image]
Mantella pulchra is a shy, seldom kept species.
It also appears to be tolerant of a wide range of temperatures

20 - 25mm. Confusion reigns with this species as most were imported as Mantella cowanii before 1994. It is easy to distinguish because its dorsum (particularly is head) possesses a silvery brown sheen. The flanks nearly always have lime green or blue patches. It is a plump but extremely agile species and is certainly the most nervy mantella although it often searches for food in open daylight and males are quite bold when excited. I have found that it thrives in conditions similar to the golden mantella although it is more tolerant of warm temperatures. Breeding is rather infrequent mainly because females are not easily coaxed into producing eggs.

 

Haraldmeier's mantella (Mantella haraldmeieri)
21 - 29mm Discovered in 1981 in the extreme south-east of the Madagascar and is rarely imported into the hobby probably due to the lack of demand. Distinguished from the very similar M.pulchra by the heart-shaped marking on the brownish dorsum. The front limbs also tend to be a whitish-green and the hind-limbs a dull orange. It produces relatively large clutches of 60 or more yellowish-white eggs.



Bernhard's mantella (Mantella bernhardi)

 [image]
Mantella bernhardi is the most recently named
species and a wonderful vivarium subject

To 21mm (smaller in males). I have to confess that the behaviour of this very rare species in captivity has made it a great favourite of mine. All the specimens I have acquired have been in extremely poor condition yet after a bit of gentle care they have responded magnificently. The male is by far the most boisterous of the mantellas and possesses a good vocal sac which he is proud to exhibit given any opportunity. It even attempts to mate with my finger or a pair of forceps! The general colour is black apart from the inside of the limbs which are a dazzling yellow. The skin is known to be extremely toxic hence is boldness. It demands warm, humid conditions and prefers fruitfly or aphids to most other foods. Males are also distinguished by the horseshoe- shaped throat markings which extends further than the female. It dislikes enclosed spaces so unlike some species will not survive long being couped up in a margarine tub or similar container. Unfortunately it is unlikely to be available in captivity for much longer due to its precarious position in the wild.

THE ARBOREAL MANTELLA GROUP
This is the smallest group yet contains the most divergent species.

Arboreal mantella (Mantella laevigata)
25 - 30mm. A wonderful vivarium subject and is the only true scansorial species inhabiting plants several metres off the ground. In captivity it requires sturdy branches fixed diagonally which have extensive holes drilled in them. These holes must be lined with moss and regularly dampened down to create the necessary high humidity. Eggs are always laid in such elevated locations (never on the ground) and tadpoles hatch out when such holes fill with water or may even continue development entirely within the egg casing (often devouring each other until just 1 or 2 frogets emerge). Noticeably froglets hatching out from the latter are only half the size of tadpoles that have developed normally. I suggest flushing the eggs out of the holes into an aquarium after 10 - 12 days. Metamorphosis is complete after a further 58 or so days. Climbing mantellas spend much of their time on the ground hunting for grubs, crickets, fruitflies and termites and they especially like small waxworm. The general colour is green with black flanks, limbs and lower head. The venter is black with white stipples. It digits have specifically evolved for its arboreal habits possessing splayed endings.

 

Marojezy mantella (Mantella sp.)
To 30mm. From the Marojezy mountains in extreme north-east Madagascar. Discovered in 1993. It differs mainly in having a white line around the lip, a horseshoe-shaped marking on the throat (absent in Mantella laevigata) and specialized digits are absent. This species is not known to actively climb (it is placed here because of its syntopic relationship with the former species and eggs are always deposited on the ground. It particularly inhabits the cool, stony mountain brooks where it is known to feed on small crustaceans that crawl out onto the rocks. I know of someone who feeds this species water shrimp (Asellus) native to the beds of our own UK brooks. Overall it is a slimmer species than the climbing mantella and can attain 32mm. Requires a temperature no greater than 74F. (preferably cooler) in captivity due to its high altitude distribution.


Literature Cited;
Field Guide to the Amphibians & Reptiles of Madagascar - Glaw & Vences (2nd edition)
Amphibians in Captivity (TFH) - Marc Staniszewski (1995)
Guide to owning Mantella's (TFH) - Marc Staniszewski (1997) - very brief guide
The Golden Mantella Handbook (Neurergus Books) - Marc Staniszewski (1998)
Mantella's (publisher to be announced soon) - Marc Staniszewski (due out 1999) - large, detailed guide


You can e-mail me at: marcstan@amphibian.co.uk

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All text and photo's - Copyright 1996-9 Marc Staniszewski
Most recent revision: 30/09/98

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