Mantella aurantiaca

Geographic Range

Mantella aurantiaca occupy the montane pandanus forests around Andasibe and they are typically found in isolated patches ranging throughout southeastern Madagascar.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

Golden mantellas are considered an "upland" species, due to the fact that they are found at an altitude of about 900 meters. The climate is typically moist, humid and temperate. They usually inhabit mossy or grassy mounds of forest debris that border shallow swampy waters.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• rainforest rainforest

• Wetlands
• swamp swamp

Physical Description

Adult snout vent lengths (SVLs) are typically 1.25 inches, although 1.5 inch SVLs have been reported. These frogs exhibit brilliant golden-orange coloration that is impossible to miss. They occasionally have red flash marks on the inner portion of the hind legs. The eyes of this species are jet black. The legs are very short with distinct adhesive disks found on the fingers and toes (Badger, 1995). There is sexual dimorphism. Males are generally smaller, slimmer and more angular in build than females, and tend not to call as much as other species of male mantellas. The male's ventral surface is lighter in color and therefore causes the seminiferous ducts (narrow pair of pale lines) to be visible. These ducts hava a dual purpose in males, carrying both sperm and urine. Females also have these ducts but they are, for the most part, concealed by the uterus and oviducts. The ducts in females do not carry sperm but they still function in urine transportation (Staniszewski, 1997).

• Other Physical Features
• ectothermic ectothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry
• poisonous poisonous

• Sexual Dimorphism
• female larger
• sexes shaped differently

Development

Eggs undergo rapid terrestrial development (2-6 day hatch period) and the newly hatched tadpoles either wriggle to the nearby water source or are washed into the water by storms (Bartlett, 1996). Tadpoles typically metamorphose into froglets 6 to 8 weeks after hatching. The tadpoles are primarily herbivores, feeding on algae and detritus, although some meat matter may be incorporated into the diet. Once the tadpoles become froglets, they are usually 10 to 14 mm in SVL and begin feeding on the more typical adult insect (springtails and small aphids) (Staniszewski. 1997). Sexual maturity is reached in 12 to 14 months.

• Development - Life Cycle
• metamorphosis metamorphosis

Reproduction

Males use a call consisting of a series of short notes, with three clicks per note, to attract female mates. Territorial aggression does occur in both sexes during this time, but especially in males. Intruders are sometimes grabbed around the upper body or head and are typically pushed away. The actual courtship process of this species is rather secretive and usually takes place under bark, logs, or rocks. If a non-gravid femaile is amplexed, she will flick her legs and back flip until the male releases her.

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

Mating usually occurs when there has been an abundant amount of food available and when the first substantial rain comes. Once amplexus is successfully underway, a suitable egg-laying site will be searched for. These sites usually include damp moss, crevices in logs, underneath damp bark or rocks and are always adjacent to a water source (Staniszewski, 1997). Clutches consist of 12 to 30 eggs, 2 to 3 mm in diameter and are immediately fertilized by a male, although fertilization can occur up to 2 days later and by multiple males.

• Key Reproductive Features
• iteroparous iteroparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
  • external external
• oviparous oviparous

Once the eggs are laid, parent golden mantellas have no further involvement in the development of their young.

• Parental Investment
• pre-fertilization
  • provisioning
  • protecting
    • female

Lifespan/Longevity

Mantella aurantiaca typically has a life span of 8 years.

Behavior

Mantella aurantiaca are usually colonial in nature, living in groups scattered throughout southeastern Madagascar. The male to female ratio in the wild is about 2 to 1 and is therefore reflected in the composition of these colonies, males being more plentiful than females. They are diurnal (day-active) in nature, hunting basically all day for food. Makes do have a puzzling behavior in that they are particularly reluctant to call, compared to other species of mantellas. A reason for this has not yet been positively identified, although it may have something to do with not wanting to draw attention from predators to itself or it may be a way of conserving vital energy.

• Key Behaviors
• diurnal diurnal
• motile motile
• sedentary sedentary
• social social

Communication and Perception

Golden mantellas use auditory cues, and may also use visual or chemical cues to communicate. They use their vision to locate prey.

• Communication Channels
• tactile tactile
• acoustic acoustic

• Perception Channels
• visual visual
• acoustic acoustic
• vibrations vibrations

Food Habits

Mantella aurantiaca are entirely insectivorous. A diet commonly consists of termites ( Isoptera ), ants ( Formicidae ), fruitflies ( Drosphila ), and just about any other arthropod that can be fit into the mouth. Golden mantellas are known for attempting to eat anything, even if the taste is repulsive (Bartlett, 1996).

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects
• terrestrial non-insect arthropods

Predation

The brilliant colors exhibited by M. aurantiaca can be attributed to a phenomenon called aposematic coloration, where toxic or dangerous animals use bright colors or marking to advertise their toxicity to potential predators. Golden mantellas have toxic skin secretions, protecting them from most predators.

• Anti-predator Adaptations
• aposematic aposematic

Economic Importance for Humans: Positive

Many individuals are captured from the wild for the pet trade while some are now captive bred.

Economic Importance for Humans: Negative

Golden mantellas are toxic, although humans would not typically be exposed to this toxin if they are not harassing these frogs.

• Negative Impacts
• injures humans
  • poisonous poisonous

Conservation Status

Several human-caused factors are causing a decline in native populations of the golden mantella. Overcollection for the pet industry, introduced predatory species, major deforestation in Madagascar and human encroachment are all among the leading causes fueling this raging decline.

Other Comments

Mantella aurantiaca was, for many years, classified as a member of the posion arrow genus Dendrobates . Their phylogenetic position has been somewhat unstable over the years.

Additional Links

AmphibiaWeb

Encyclopedia of Life

Contributors

Thomas Loch (author), Michigan State University, James Harding (editor), Michigan State University.

References

Badger, D. 1995. Frogs . NY: Barnes and Noble, Inc.

Bartlett, R. 1996. Frogs, Toads, and Treefrogs . NY: Barron's Educational Series.

Staniszewski, M. 1997. "Mantella FAQ" (On-line). Accessed 11/03/99 at http://www.amphibian.co.uk/mantella.html .