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Order: Gymnophiona
Family: Caeciliidae
The modern caecilians, with their limbless, superficially worm-like or snake-like bodies, are perhaps the most unusual amphibians in appearance, and their behaviour can be equally strange. The order Gymnophiona (the caecilians) is thought to have diverged from other amphibian lineages about 370 million years ago in the Devonian period, over 150 million years before the first mammal. The earliest caecilian is sometimes reported to be known from the early Jurassic period in Arizona, U.S.A. 190 million years ago and was named Eocaecilia micropodia because it had very small legs and feet. It also had well-developed eyes, suggesting that it was not an entirely subterranean species and may have had more in common with salamanders than with the modern caecilians that became its descendents, and its status as a caecilian is in some doubt. Eocaecilia and Gymnophiona have long independent histories, and it is also thought that they may represent separate lineages that developed similar closed-roof skull morphology convergently, i.e. the same trait arose twice in different parts of the amphibian tree of life, which means that species possessing identical traits are not always closely related (e.g. both bats and birds have wings, but flight evolved independently in these two lineages). This means that the morphology of Eocaecilia may not be the best model for the ancestral caecilian.
Modern caecilians certainly evolved from limbed ancestors however, and therefore underwent major changes in their evolutionary history as they developed elongated, externally-segmented bodies and much-reduced eyes, and lost their limbs, limb girdles and, in the case of the most recently evolved species, their tails. The only currently known fossils of ‘true’ caecilians are three records of isolated vertebrae (back bones) from the Late Cretaceous period (about 100-93 million years ago) of Sudan in Africa, and the Palaeocene (65-53 million years ago) of Brazil and Bolivia. Two older fossils from the Cretaceous of Morocco and the Jurassic of North America are not ‘true’ caecilians, but have been argued to be more closely related to caecilians than any other amphibians. The oldest of these two possible members of the caecilian ‘stem’ lineage is Eocaecilia macropodia. Its small fore- and hind-limbs are thought to have been retained from the last common ancestor of the caecilians and the frogs+salamanders lineage.
Carl Linnaeus (the founder of modern taxonomy) described the first species of caecilian (Caecilia tentaculata) in 1758 and initially thought they were related to snakes. The taxonomic order name “Gymnophiona” is actually derived from the Greek words gymnos (meaning naked) and ophis (meaning snake). The caecilians where therefore originally refered to as “naked snakes” because they lack external scales covering their entire body and the first scientific efforts to classify them could not conceive that they were instead closely related to frogs and salamanders. Many caecilians do actually have scales, but these are small, more fish-like than snake-like, and hidden in folds in the skin, although the Sagalla caecilian and its close relatives (in the Boulengerula genus) have no scales.
The family Caeciliidae (the “common caecilians”) are thought to have branched off from the rest of the amphibian tree over 160 million years ago in the upper Jurrasic period when dinosaurs were still abundant in the earth’s terrestrial ecosystems. Boulengerula (the genus of the Sagalla caecilian) diverged within this family almost 100 million years ago in the late Cretaceous period and there are now just seven described species in this genus (which is also referred to as “Boulenger's Caecilians”), all present in East and Central Africa. This means they are as separated in time from their closest relative as humans are from elephants. Despite there only being seven species of Boulengerula caecilians, this genus is thought to be the most species-rich of all the African caecilian groups and it is probable that more species are yet to be found.
The Sagalla caecilian was only recently discovered as a new species in 2005 and was collected from Sagalla Hill, an isolated mountain block of the Taita Hills range in the Eastern Arc Mountains of Kenya. This species differs substantially from its closest relative Boulengerula taitanus (the Taita African caecilian – which is also found in the Taita Hills) and from all other members of Boulengerula in its colouration, phallus (a penis-like organ – all caecilians have internal fertilisation) and other morphological features. The Eastern Arc Mountains are one of the earth's major biodiversity hotspots, and many species in this region are restricted to one mountain block within the arc.
Modern caecilians certainly evolved from limbed ancestors however, and therefore underwent major changes in their evolutionary history as they developed elongated, externally-segmented bodies and much-reduced eyes, and lost their limbs, limb girdles and, in the case of the most recently evolved species, their tails. The only currently known fossils of ‘true’ caecilians are three records of isolated vertebrae (back bones) from the Late Cretaceous period (about 100-93 million years ago) of Sudan in Africa, and the Palaeocene (65-53 million years ago) of Brazil and Bolivia. Two older fossils from the Cretaceous of Morocco and the Jurassic of North America are not ‘true’ caecilians, but have been argued to be more closely related to caecilians than any other amphibians. The oldest of these two possible members of the caecilian ‘stem’ lineage is Eocaecilia macropodia. Its small fore- and hind-limbs are thought to have been retained from the last common ancestor of the caecilians and the frogs+salamanders lineage.
Carl Linnaeus (the founder of modern taxonomy) described the first species of caecilian (Caecilia tentaculata) in 1758 and initially thought they were related to snakes. The taxonomic order name “Gymnophiona” is actually derived from the Greek words gymnos (meaning naked) and ophis (meaning snake). The caecilians where therefore originally refered to as “naked snakes” because they lack external scales covering their entire body and the first scientific efforts to classify them could not conceive that they were instead closely related to frogs and salamanders. Many caecilians do actually have scales, but these are small, more fish-like than snake-like, and hidden in folds in the skin, although the Sagalla caecilian and its close relatives (in the Boulengerula genus) have no scales.
The family Caeciliidae (the “common caecilians”) are thought to have branched off from the rest of the amphibian tree over 160 million years ago in the upper Jurrasic period when dinosaurs were still abundant in the earth’s terrestrial ecosystems. Boulengerula (the genus of the Sagalla caecilian) diverged within this family almost 100 million years ago in the late Cretaceous period and there are now just seven described species in this genus (which is also referred to as “Boulenger's Caecilians”), all present in East and Central Africa. This means they are as separated in time from their closest relative as humans are from elephants. Despite there only being seven species of Boulengerula caecilians, this genus is thought to be the most species-rich of all the African caecilian groups and it is probable that more species are yet to be found.
The Sagalla caecilian was only recently discovered as a new species in 2005 and was collected from Sagalla Hill, an isolated mountain block of the Taita Hills range in the Eastern Arc Mountains of Kenya. This species differs substantially from its closest relative Boulengerula taitanus (the Taita African caecilian – which is also found in the Taita Hills) and from all other members of Boulengerula in its colouration, phallus (a penis-like organ – all caecilians have internal fertilisation) and other morphological features. The Eastern Arc Mountains are one of the earth's major biodiversity hotspots, and many species in this region are restricted to one mountain block within the arc.
With its elongated body, “annuli” which resemble segments, lack of limbs and borrowing lifestyle, the Sagalla caecilian superficially resembles a large earthworm. This species has strongly pigmented skin, giving it a brownish appearance with a pinkish-red tinge, and whitish grooves that divide the body skin cross-ways into narrow segments or annuli. Sagalla caecilians grow to lengths of almost 300 mm.
The body of this species is adapted for burrowing. Like other caecilians, the Sagalla caecilian has a bony skull which it uses to push through the soil, and the skin is very tough, with the underlying skin layers being closely in contact with the skull bones to stop them being sheared away during digging. The outer layers of the skin are also strengthened with keratin, which is the same material that forms our hair and fingernails. Sagalla caecilians also have very reduced eyes, which are not visible because they are covered by a layer of bone and a protective skin which is the same colour as the rest of the body. There is not even a conspicuous depression or elevation in the region where the eyes would be expected to lie. The common name caecilian is actually derived from the Latin word caecus (meaning blind) in reference to the small or sometimes vestigial eyes of these animals. The idea that caecilians are blind is a misconception, even when the eyes are covered by a layer of skin and bone. This skin and bone cover reduces their vision substantially but they are probably still capable of simple dark-light perception.
They possess retractable tentacles located either side of the head between the nostril and the place where their eyes should be found, and close to the margin of the upper lip. The tentacles are short and globular, and emanate from small, circular holes. The function of these tentacles has not been studied in Boulenger’s caecilians, and it is thought they could be tactile (used to sense surroundings through touch), chemosensory (able to detect chemical cues from the environment), or both. The Sagalla caecilian has a relatively large mouth containing many teeth in three different rows (two in the upper jaw and one in the lower). Many caecilians have annuli right up to the posterior end of their bodies. However, Boulenger’s caecilians are unusual in having an unsegmented ‘terminal shield’ instead.
One of the features that differentiates the Sagalla caecilian from its closest relative, the Taita African caecilian (Boulengerula taitanus), is that males possess a differently-shaped phallus or penis-like organ (also called the phallodeum), which has broad bumps aligned along the side ridges near its tip. Unlike frogs and salamanders, male caecilians use the phallus (which is actually an eversion of the single chamber into which the digestive, urinary, and reproductive systems empty, also called the cloaca) to copulate with and transfer sperm to females. Adult Taita African caecilians are also a different colour to the Sagalla caecilian, being bluish-black
The body of this species is adapted for burrowing. Like other caecilians, the Sagalla caecilian has a bony skull which it uses to push through the soil, and the skin is very tough, with the underlying skin layers being closely in contact with the skull bones to stop them being sheared away during digging. The outer layers of the skin are also strengthened with keratin, which is the same material that forms our hair and fingernails. Sagalla caecilians also have very reduced eyes, which are not visible because they are covered by a layer of bone and a protective skin which is the same colour as the rest of the body. There is not even a conspicuous depression or elevation in the region where the eyes would be expected to lie. The common name caecilian is actually derived from the Latin word caecus (meaning blind) in reference to the small or sometimes vestigial eyes of these animals. The idea that caecilians are blind is a misconception, even when the eyes are covered by a layer of skin and bone. This skin and bone cover reduces their vision substantially but they are probably still capable of simple dark-light perception.
They possess retractable tentacles located either side of the head between the nostril and the place where their eyes should be found, and close to the margin of the upper lip. The tentacles are short and globular, and emanate from small, circular holes. The function of these tentacles has not been studied in Boulenger’s caecilians, and it is thought they could be tactile (used to sense surroundings through touch), chemosensory (able to detect chemical cues from the environment), or both. The Sagalla caecilian has a relatively large mouth containing many teeth in three different rows (two in the upper jaw and one in the lower). Many caecilians have annuli right up to the posterior end of their bodies. However, Boulenger’s caecilians are unusual in having an unsegmented ‘terminal shield’ instead.
One of the features that differentiates the Sagalla caecilian from its closest relative, the Taita African caecilian (Boulengerula taitanus), is that males possess a differently-shaped phallus or penis-like organ (also called the phallodeum), which has broad bumps aligned along the side ridges near its tip. Unlike frogs and salamanders, male caecilians use the phallus (which is actually an eversion of the single chamber into which the digestive, urinary, and reproductive systems empty, also called the cloaca) to copulate with and transfer sperm to females. Adult Taita African caecilians are also a different colour to the Sagalla caecilian, being bluish-black
The Sagalla caecilian lives underground, burrowing through the soil using its strong, bony head to compact soil and produce a burrow. They move through the soil by body undulation, and search for their prey, possibly by collecting chemical and tactile signals. In addition to their sense of smell through their nose, retractable tentacle sensors either side of their head near to their nostrils may also function to transmit chemical messages from the environment to the nasal cavity, which aids the caecilian in finding prey. The feeding mechanism of the Sagalla caecilian’s close relative (the Taita Hill’s caecilian) has been closely studied. They were found to employ rotational feeding, which is where the caecilian grabs a prey item and then rotates about the long axis of their body. This is a common behaviour in gape-limited creatures, and would seem to serve a dual purpose in caecilians. First, it may aid the breaking up of oversized food items. However, it is thought that caecilian prey is not always oversized so a second function of rotation may instead help them to judge prey size through the detection of how much spin force is required to move the object. Caecilians spend their time in narrow, dark tunnels, so rotational feeding allows the caecilian to gauge more information about its surroundings and prey.
The observation of caecilian behaviour is rendered difficult by their subterranean lifestyles. Many caecilian species are dietary generalists, feeding on earthworms and various species of other soil-dwelling invertebrate. Boulenger’s caecilians also feed on a range of prey items, most commonly termites and earthworms. Caecilians catch their prey using a variety of methods, which range from a “sit and wait” or stealth strategy, whereby they slowly approach the prey and then quickly seize it using a strong grab of the jaws, to active hunting of prey items using an acute sense of smell. Their main predators are probably snakes and birds, although they are thought to possess some defense mechanisms against predation. Their skin contains mucus and poison glands (as found in other amphibians), and caecilians are probably quite toxic to many potential attackers. They are often well camouflaged and spend the vast majority of their time underground away from a wide variety of potential predators. The principal predators of the Sagalla caecilian are thought to be driver ants (which are sometimes known as “killer” ants). Living in colonies of up to 20 million individuals, driver ants are a formidable force and may tackle prey up to the size of a zebra, although the bulk of their diet consists of earth worms. Since the Sagalla caecilian occupies a similar habitat to the earth worms, they too are hunted in their burrows.
All caecilians are thought to have internal fertilisation, in that the eggs are fertilised by the male’s sperm inside the female and not when they are being laid. Virtually nothing is known of caecilian mate recognition or courtship, although some aquatic species have been observed performing an undulating dance before mating. During mating, the male everts and inserts his phallus into the cloaca (or reproductive opening) of the female for up to several hours. The Sagalla caecilian is egg-laying (or “oviparous”), and in caecilians this means that the female lays her eggs in an underground chamber and then guards them until they hatch. This species is presumed to resemble its close relatives in having direct development, so the young hatch out from the eggs without first passing through a free-living larval stage. Caecilians can produce clutches of two to more than 100 eggs, and a Sagalla caecilian female has previously been found bearing five eggs.
It had been thought that following the hatching of the eggs in oviparous species, caecilian mothers provided little or no further care of their offspring. However, the Sagalla caecilian’s closest relative, the Taita African caecilian (Boulengerula taitanus), has recently been shown to exhibit the extraordinary behaviour of “maternal dermatotrophy” or skin feeding its young. The hatchlings possess special teeth that allow them to peel and eat their mother's skin, which contains a high level of fat and other nutrients. Indicated by the presence of special teeth in the hatchlings of other oviparous caecilians, skin feeding may have evolved in caecilians around 150 million years ago in the late Jurassic period. The young of the Taita African caecilian are therefore provisioned with both yolk whilst in the egg and, subsequently, a diet of the nutrient-rich skin of their mother when they hatch. This remarkable level of parental care has not yet been observed in the Sagalla caecilian. The specialised teeth have not been found in their independent young, but it is unclear whether this is because they had already been shed and replaced with the adult-like dentition in the observed stages or whether they do not skin-feed. More studies are needed to fully discover the life history of the Sagalla caecilian, although skin-feeding is expected to occur in the Sagalla caecilian based on its presence in its sister species and the possibly broader distribution of this trait among the closer relatives of Boulenger’s caecilians.
Sagalla caecilians possess a single developed lung (the left lung being considerably reduced or missing as is often the case in snakes) and they are also capable of gaseous exchange (or respiration) through their skin and the lining of their mouth. Local farmers on Sagalla Hill have reported that the Sagalla caecilian is more commonly encountered during the wet seasons, which is also known to be the case for the Taita African caecilian. The rains may encourage the Sagalla caecilian to move up into the upper layers of the soil where it becomes more visible to the farmers that cultivate the land. The Sagalla caecilian requires moist soil, both to maintain their moist skin and to provide a suitable habitat for their prey
The observation of caecilian behaviour is rendered difficult by their subterranean lifestyles. Many caecilian species are dietary generalists, feeding on earthworms and various species of other soil-dwelling invertebrate. Boulenger’s caecilians also feed on a range of prey items, most commonly termites and earthworms. Caecilians catch their prey using a variety of methods, which range from a “sit and wait” or stealth strategy, whereby they slowly approach the prey and then quickly seize it using a strong grab of the jaws, to active hunting of prey items using an acute sense of smell. Their main predators are probably snakes and birds, although they are thought to possess some defense mechanisms against predation. Their skin contains mucus and poison glands (as found in other amphibians), and caecilians are probably quite toxic to many potential attackers. They are often well camouflaged and spend the vast majority of their time underground away from a wide variety of potential predators. The principal predators of the Sagalla caecilian are thought to be driver ants (which are sometimes known as “killer” ants). Living in colonies of up to 20 million individuals, driver ants are a formidable force and may tackle prey up to the size of a zebra, although the bulk of their diet consists of earth worms. Since the Sagalla caecilian occupies a similar habitat to the earth worms, they too are hunted in their burrows.
All caecilians are thought to have internal fertilisation, in that the eggs are fertilised by the male’s sperm inside the female and not when they are being laid. Virtually nothing is known of caecilian mate recognition or courtship, although some aquatic species have been observed performing an undulating dance before mating. During mating, the male everts and inserts his phallus into the cloaca (or reproductive opening) of the female for up to several hours. The Sagalla caecilian is egg-laying (or “oviparous”), and in caecilians this means that the female lays her eggs in an underground chamber and then guards them until they hatch. This species is presumed to resemble its close relatives in having direct development, so the young hatch out from the eggs without first passing through a free-living larval stage. Caecilians can produce clutches of two to more than 100 eggs, and a Sagalla caecilian female has previously been found bearing five eggs.
It had been thought that following the hatching of the eggs in oviparous species, caecilian mothers provided little or no further care of their offspring. However, the Sagalla caecilian’s closest relative, the Taita African caecilian (Boulengerula taitanus), has recently been shown to exhibit the extraordinary behaviour of “maternal dermatotrophy” or skin feeding its young. The hatchlings possess special teeth that allow them to peel and eat their mother's skin, which contains a high level of fat and other nutrients. Indicated by the presence of special teeth in the hatchlings of other oviparous caecilians, skin feeding may have evolved in caecilians around 150 million years ago in the late Jurassic period. The young of the Taita African caecilian are therefore provisioned with both yolk whilst in the egg and, subsequently, a diet of the nutrient-rich skin of their mother when they hatch. This remarkable level of parental care has not yet been observed in the Sagalla caecilian. The specialised teeth have not been found in their independent young, but it is unclear whether this is because they had already been shed and replaced with the adult-like dentition in the observed stages or whether they do not skin-feed. More studies are needed to fully discover the life history of the Sagalla caecilian, although skin-feeding is expected to occur in the Sagalla caecilian based on its presence in its sister species and the possibly broader distribution of this trait among the closer relatives of Boulenger’s caecilians.
Sagalla caecilians possess a single developed lung (the left lung being considerably reduced or missing as is often the case in snakes) and they are also capable of gaseous exchange (or respiration) through their skin and the lining of their mouth. Local farmers on Sagalla Hill have reported that the Sagalla caecilian is more commonly encountered during the wet seasons, which is also known to be the case for the Taita African caecilian. The rains may encourage the Sagalla caecilian to move up into the upper layers of the soil where it becomes more visible to the farmers that cultivate the land. The Sagalla caecilian requires moist soil, both to maintain their moist skin and to provide a suitable habitat for their prey
This species is thought to have originally been present in montane forest soils, as well as that covered by bushy shrub vegetation, but this habitat has now been transformed into shambas (Kenyan smallholder farms). Most of the Sagalla caecilians observed by scientists so far have been unearthed from soil underneath banana plants or beneath decomposing organic debris within these farms, especially near to streams. The Sagalla caecilian therefore seems to be tolerant of small-scale farming activities. However, the density of animals is much higher near streams than in shambas away from streams, so the area of potentially preferred habitat within the possible range of the Sagalla caecilian is very small. Although Boulenger’s caecilians require moist soils, their reproductive mode (direct development of terrestrial eggs) has liberated them from a dependence on streams or other water bodies for their reproduction. The species has not been found in the Eucalyptus plantations that cover much of the Sagalla Hill area (due to soil desiccation, toxic accumulations of Eucalyptus leaf litter, and resultant limited prey), and is only found in very low abundance in the small remaining area of natural forest on the ridge of Sagalla Hill. This is potentially because this remnant forest is at a higher elevation than that apparently favoured by the species, or it could be due to the absence of suitable soil conditions or streamside habitat.
Currently very little is known about what constitutes suitable or optimal habitat for caecilians. For example, specimens of the Taita African caecilian observed in shambas have been found to be significantly smaller but more abundant than those inhabiting naturally forested areas of the Taita Hills. It is therefore difficult to determine whether the human alteration of the Sagalla caecilian’s habitat is having a long-term effect upon this species.
Currently very little is known about what constitutes suitable or optimal habitat for caecilians. For example, specimens of the Taita African caecilian observed in shambas have been found to be significantly smaller but more abundant than those inhabiting naturally forested areas of the Taita Hills. It is therefore difficult to determine whether the human alteration of the Sagalla caecilian’s habitat is having a long-term effect upon this species.
The Sagalla caecilian is known only from elevations of about 1,000 metres above sea level on Sagalla Hill (also spelt Sagala Hill), in the Taita Hills of the Eastern Arc mountains in south-eastern Kenya. This mountain block is isolated from other similar habitat by the arid Tsavo plains, and so the range of this species is believed to be restricted to the 29 km² within this block that are above 1,000 metres above sea level. This is an area about half the size of Manhattan Island.
No population data are currently available for this species. However, within its extremely restricted range of about 29 km², the Sagalla caecilian is considered to be common in a small number of suitable habitats.
No population data are currently available for the Sagalla caecilian, but the population trend is assumed to be in decline by the IUCN Red List of Threatened Species.
The Sagalla caecilian is listed as Critically Endangered in the IUCN Red List of Threatened Species because it has an extent of occurrence of less than 100 km², is restricted to one location, and its habitat is undergoing a continuing decline in quality.
Sagalla Hill has been significantly deforested and only a small amount of natural forest remains within the range of the Sagalla caecilian. However, it is not clear whether these caecilians might sometimes benefit from human modified or disturbed habitat. The Sagalla caecilian appears to be tolerant of small-scale farming activities such as those practiced in the shambas on Sagalla Hill. The continued expansion of these farming activities has in recent years resulted in the removal of streamside vegetation causing severe flooding and an increase in the erosion of river banks. The substantial loss of earth washed away in these floods has removed soil where the Sagalla caecilian is known to breed and occur at its highest densities.
The main threats to the Sagalla caecilian would appear to be linked to the removal of native vegetation, with a number of negative consequences for this species. Clearance of native vegetation has increasingly led to the cultivation of steep slopes and the resultant erosion of good, thick soils for the Sagalla caecilian. Vegetation removal has also caused the drying out of soils in many areas of this species’ range, rendering the soil uninhabitable for the Sagalla caecilian because they probably require moist conditions. Shambas now extend all the way up to the streams in the area, which is drying out some of the best places for this species as they thrive in moist streamside soils. The conspicuous lack of Sagalla caecilians in the Eucalyptus plantations may also indicate that the species is unable to survive around this non-indigenous tree species. Eucalyptus trees probably affect the Sagalla caecilian in two main ways. Firstly these trees desiccate their surrounding, leading to compaction of the soil. Secondly, the presence of Eucalyptus trees has led to a thick accumulation of toxic leaf litter which decomposes very slowly and does not allow for the build up of communities of local insects and other soil invertebrates. This means not only is the soil rendered too dry and hard for Sagalla caecilians, but there are also no prey items.
Eucalyptus plantations have been present on Sagalla Hill for many years and many belong to the Kenyan government, making their removal very difficult. Continued presence (and any expansion) of the Sagalla Hill Eucalyptus plantations will negatively impact remaining populations of the Sagalla caecilian. Chemicals used in farming on Sagalla Hill, as well as other pollutants, may also pose a threat to this species.
The main threats to the Sagalla caecilian would appear to be linked to the removal of native vegetation, with a number of negative consequences for this species. Clearance of native vegetation has increasingly led to the cultivation of steep slopes and the resultant erosion of good, thick soils for the Sagalla caecilian. Vegetation removal has also caused the drying out of soils in many areas of this species’ range, rendering the soil uninhabitable for the Sagalla caecilian because they probably require moist conditions. Shambas now extend all the way up to the streams in the area, which is drying out some of the best places for this species as they thrive in moist streamside soils. The conspicuous lack of Sagalla caecilians in the Eucalyptus plantations may also indicate that the species is unable to survive around this non-indigenous tree species. Eucalyptus trees probably affect the Sagalla caecilian in two main ways. Firstly these trees desiccate their surrounding, leading to compaction of the soil. Secondly, the presence of Eucalyptus trees has led to a thick accumulation of toxic leaf litter which decomposes very slowly and does not allow for the build up of communities of local insects and other soil invertebrates. This means not only is the soil rendered too dry and hard for Sagalla caecilians, but there are also no prey items.
Eucalyptus plantations have been present on Sagalla Hill for many years and many belong to the Kenyan government, making their removal very difficult. Continued presence (and any expansion) of the Sagalla Hill Eucalyptus plantations will negatively impact remaining populations of the Sagalla caecilian. Chemicals used in farming on Sagalla Hill, as well as other pollutants, may also pose a threat to this species.
The Sagalla caecilian is not known from any protected areas, although there are some limited conservation initiatives occurring for this species. An important first step was to raise the profile of this species among the local people of Sagalla Hill. A competition was organised for people in the small Sagalla community to find a new name for the Sagalla caecilian in the local dialect, kisagalla. On Sagalla Hill, the local name of the caecilian has always been “ming’ori” or earthworm. Providing this species with its own identity is a critical component of raising awareness about its plight. Patrick Malonza of the National Museums of Kenya (co-describer of this species and one of the organisers of the competition) explained the importance of naming the species locally: “If the animal has a local kisagalla name, we think that Sagalla people may recognise it for the special endemic species that it is. They have something unique to be proud of.”
Conservation International (CI), through its Critical Ecosystems Partnership Fund (CEPF), supports conservation projects in the region of Sagalla Hill. The Taita Hills (including Sagalla, Dawida, Kasigau and Mbololo) are part of the Eastern Arc Mountains and coastal forests (in Kenya and Tanzania) hotspot of biodiversity, and are therefore a conservation focus of CI. Many of the unique species in this region are threatened by habitat loss and degradation. Funding from CEPF is being used to understand the amphibian biodiversity of the region, as well as looking for sustainable ways of conserving the environment for people, animals and plants. Local and international scientists are currently measuring and monitoring all of the amphibian species in the area in the remaining naturally indigenous forests, exotic plantations and shambas. Working thorough local counterparts, this project aims to train local field assistants with a view to developing a sustainable long-term monitoring program.
However, much more can still be done to specifically conserve the Sagalla caecilian and its habitat.
Conservation International (CI), through its Critical Ecosystems Partnership Fund (CEPF), supports conservation projects in the region of Sagalla Hill. The Taita Hills (including Sagalla, Dawida, Kasigau and Mbololo) are part of the Eastern Arc Mountains and coastal forests (in Kenya and Tanzania) hotspot of biodiversity, and are therefore a conservation focus of CI. Many of the unique species in this region are threatened by habitat loss and degradation. Funding from CEPF is being used to understand the amphibian biodiversity of the region, as well as looking for sustainable ways of conserving the environment for people, animals and plants. Local and international scientists are currently measuring and monitoring all of the amphibian species in the area in the remaining naturally indigenous forests, exotic plantations and shambas. Working thorough local counterparts, this project aims to train local field assistants with a view to developing a sustainable long-term monitoring program.
However, much more can still be done to specifically conserve the Sagalla caecilian and its habitat.
It is an urgent priority to restore the vegetation along stream banks and on steep slopes within this species’ range in order to minimise erosion and loss of important soil habitat for the Sagalla caecilian.
The Sagalla caecilian is a very recently discovered species, and so little is currently known of its habits, habitat requirements and population dynamics. Further study of the ecology of this species would benefit future conservation panning as it may help inform decisions about habitat management and protection. This should involve the training of local conservationists, which could be achieved by appointing a local EDGE Fellow for the Sagalla caecilian.
Plans to remove the Eucalyptus plantations in the area would also be very beneficial for the species, as well as other native biodiversity. If the Eucalyptus plantations are removed, it is imperative that these areas are replanted with preferably native vegetation to stabilise the soil and prevent further erosion and desiccation. However, since this species has often been found associated with banana plantations, it is possible that the ecologically sensitive cultivation of bananas may also benefit this species, whilst providing an income for local communities. Because many of the Eucalyptus plantations on Sagalla Hill are government owned, their removal may require appealing to a policy-level decision making process. However, Eucalyptus trees were also planted on locally owned land, within the shambas. An initiative that provides subsidies for the removal of these locally-owned trees would be a positive step for the conservation of the Sagalla caecilian. Furthermore, encouraging ecologically sensitive arboriculture using native species (i.e. creating mixed species tree plantations that may also provide income for local people) and creating a special nature reserve within good habitat for the Sagalla caecilian would also be enormously beneficial for the survival of this species.
The Sagalla caecilian is a very recently discovered species, and so little is currently known of its habits, habitat requirements and population dynamics. Further study of the ecology of this species would benefit future conservation panning as it may help inform decisions about habitat management and protection. This should involve the training of local conservationists, which could be achieved by appointing a local EDGE Fellow for the Sagalla caecilian.
Plans to remove the Eucalyptus plantations in the area would also be very beneficial for the species, as well as other native biodiversity. If the Eucalyptus plantations are removed, it is imperative that these areas are replanted with preferably native vegetation to stabilise the soil and prevent further erosion and desiccation. However, since this species has often been found associated with banana plantations, it is possible that the ecologically sensitive cultivation of bananas may also benefit this species, whilst providing an income for local communities. Because many of the Eucalyptus plantations on Sagalla Hill are government owned, their removal may require appealing to a policy-level decision making process. However, Eucalyptus trees were also planted on locally owned land, within the shambas. An initiative that provides subsidies for the removal of these locally-owned trees would be a positive step for the conservation of the Sagalla caecilian. Furthermore, encouraging ecologically sensitive arboriculture using native species (i.e. creating mixed species tree plantations that may also provide income for local people) and creating a special nature reserve within good habitat for the Sagalla caecilian would also be enormously beneficial for the survival of this species.
Project Manager for the Sagalla Caecilian conservation project
AmphibiaWeb: Information on amphibian biology and conservation [web application]. 2006. Berkeley, California: AmphibiaWeb. Available: Global Amphibian Assessment. Accessed: 08 December 2006.
Evans, S.E., Milner, A.R. and Werner, C. 1996. Sirenid salamanders and gymnophionan amphibian from the Cretaceous of the Sudan. Palaeontology 39: 77-95.
Frost, Darrel R. 2006. Amphibian Species of the World: an Online Reference. Version 4 (17 August 2006). Electronic Database accessible at:. American Museum of Natural History, New York, USA.
Frost, D. R., Grant, T., Faivovich, J., Bain, R.H., Haas, A., Haddad, C. F. B., De Sá, R.O., Channing, A., Wilkinson, M., Donnellan, S.C., Raxworthy, C.J., Campbell, J.A., Blotto, B.L., Moler, P., Drewes, R.C., Nussbaum, R.A., Lynch, J.D., Green, D.M., and Wheeler, W.C. 2006. The Amphibian Tree of Life. Bulletin of the American Museum of Natural History 297: 1-370.
Gower D. J., & Wilkinson, M. 2005. The conservation biology of caecilians. Conservation Biology 19: 45-55.
Gower, D. J., Loader, S. P., Moncrieff, C. B. and Wilkinson, M. 2004. Niche separation and comparative abundance of Boulengerula boulengeri and Scolecomorphus vittatus (Amphibia: Gymnophiona) in an East Usambara forest, Tanzania. African Journal of Herpetology 53: 183-190.
Halliday, T. and Adler, C. (eds.). 2002. The new encyclopedia of reptiles and amphibians. Oxford University Press, Oxford.
IUCN, Conservation International and NatureServe. 2006. Global Amphibian Assessment. Global Amphibian Assessment. Accessed on 08 December 2006.
Jones, D. T., Loader, S. P. and Gower, D. J. 2006. Trophic ecology of East African caecilians (Amphibia: Gymnophiona), and their impact on forest soil invertebrates. Journal of Zoology, London 269: 117-126.
Kupfer, A., Muller, H., Jared, C., Antoniazzi, M. M., Nussbaum, R. A., Greven, H. & Wilkinson, M. 2006. Parental investment by skin feeding in a caecilian amphibian. Nature 440: 926-929.
Malonza, P.K. & Measey, G.J. 2005. Life history of an African caecilian: Boulengerula taitanus (Caeciilidae: Amphibia: Gymnophiona). Tropical Zoology 18: 49-66.
Measey, G. J. 2004. Are caecilians rare? An East African perspective. Journal of East African Natural History 93: 97-117.
Measey, G. J. 2007. When is an earthworm not an earthworm? When it’s a Critically Endangered amphibian. The Story of the Kilima-mrota. Personal communication.
Measey, G. J. and Barot, S. 2006. Evidence of seasonal migration in a tropical subterranean vertebrate. Journal of Zoology 269(1) : 29-37.
Measey, G. J. and Herrel, A. 2006. Rotational feeding in caecilians: putting a spin on the evolution of cranial design. Biology Letters 2: 485-487.
Müller, H., Measey, G.J., Loader, S.P. and Malonza, P.K. 2005. A new species of Boulengerula Tornier (Amphibia: Gymnophiona: Caeciliidae) from an isolated mountain block of the Taita Hills, Kenya. Zootaxa 1004: 37-50.
Measey, J., Malonza, P. & Mueller, H. 2006. Boulengerula niedeni. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. 2007 IUCN Red List of Threatened Species. Downloaded on 17 September 2007. Obst, F.J., Richter, K. and Jacob, U. 1984. The Completely Illustrated Atlas of Reptiles and Amphibians for the Terrarium. T.F.H. Publication Inc., N.J., U.S.A.
Roelants, K., Gower, D. J., Wilkinson, M., Loader, S. P., Biju, S. D., Guillaume, K., Moiau, L. and Bossuyt, F. 2007. Global patterns of diversification in the history of modern amphibians. Proceedings of the National Academy of Sciences 104: 887-892.
Evans, S.E., Milner, A.R. and Werner, C. 1996. Sirenid salamanders and gymnophionan amphibian from the Cretaceous of the Sudan. Palaeontology 39: 77-95.
Frost, Darrel R. 2006. Amphibian Species of the World: an Online Reference. Version 4 (17 August 2006). Electronic Database accessible at:
Frost, D. R., Grant, T., Faivovich, J., Bain, R.H., Haas, A., Haddad, C. F. B., De Sá, R.O., Channing, A., Wilkinson, M., Donnellan, S.C., Raxworthy, C.J., Campbell, J.A., Blotto, B.L., Moler, P., Drewes, R.C., Nussbaum, R.A., Lynch, J.D., Green, D.M., and Wheeler, W.C. 2006. The Amphibian Tree of Life. Bulletin of the American Museum of Natural History 297: 1-370.
Gower D. J., & Wilkinson, M. 2005. The conservation biology of caecilians. Conservation Biology 19: 45-55.
Gower, D. J., Loader, S. P., Moncrieff, C. B. and Wilkinson, M. 2004. Niche separation and comparative abundance of Boulengerula boulengeri and Scolecomorphus vittatus (Amphibia: Gymnophiona) in an East Usambara forest, Tanzania. African Journal of Herpetology 53: 183-190.
Halliday, T. and Adler, C. (eds.). 2002. The new encyclopedia of reptiles and amphibians. Oxford University Press, Oxford.
IUCN, Conservation International and NatureServe. 2006. Global Amphibian Assessment. Global Amphibian Assessment. Accessed on 08 December 2006.
Jones, D. T., Loader, S. P. and Gower, D. J. 2006. Trophic ecology of East African caecilians (Amphibia: Gymnophiona), and their impact on forest soil invertebrates. Journal of Zoology, London 269: 117-126.
Kupfer, A., Muller, H., Jared, C., Antoniazzi, M. M., Nussbaum, R. A., Greven, H. & Wilkinson, M. 2006. Parental investment by skin feeding in a caecilian amphibian. Nature 440: 926-929.
Malonza, P.K. & Measey, G.J. 2005. Life history of an African caecilian: Boulengerula taitanus (Caeciilidae: Amphibia: Gymnophiona). Tropical Zoology 18: 49-66.
Measey, G. J. 2004. Are caecilians rare? An East African perspective. Journal of East African Natural History 93: 97-117.
Measey, G. J. 2007. When is an earthworm not an earthworm? When it’s a Critically Endangered amphibian. The Story of the Kilima-mrota. Personal communication.
Measey, G. J. and Barot, S. 2006. Evidence of seasonal migration in a tropical subterranean vertebrate. Journal of Zoology 269(1) : 29-37.
Measey, G. J. and Herrel, A. 2006. Rotational feeding in caecilians: putting a spin on the evolution of cranial design. Biology Letters 2: 485-487.
Müller, H., Measey, G.J., Loader, S.P. and Malonza, P.K. 2005. A new species of Boulengerula Tornier (Amphibia: Gymnophiona: Caeciliidae) from an isolated mountain block of the Taita Hills, Kenya. Zootaxa 1004: 37-50.
Measey, J., Malonza, P. & Mueller, H. 2006. Boulengerula niedeni. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. 2007 IUCN Red List of Threatened Species. Downloaded on 17 September 2007. Obst, F.J., Richter, K. and Jacob, U. 1984. The Completely Illustrated Atlas of Reptiles and Amphibians for the Terrarium. T.F.H. Publication Inc., N.J., U.S.A.
Roelants, K., Gower, D. J., Wilkinson, M., Loader, S. P., Biju, S. D., Guillaume, K., Moiau, L. and Bossuyt, F. 2007. Global patterns of diversification in the history of modern amphibians. Proceedings of the National Academy of Sciences 104: 887-892.
if you can provide new information to update this species account or to correct any errors, please email us at info@edgeofexistence.org
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