Diversity
Genus
Agalychnis
is made up of 14 species in the family
Phyllomedusidae
.
Agalychnis
are slender frogs that have many different color combinations. They are small-to-medium-sized
frogs that are ectothermic and exhibit bilateral symmetry. This genus includes tree
frogs because they are primarily arboreal. They are predominantly green on their dorsal
sides and have yellow/orange color on their ventral sides. This coloration camouflages
them with leaves and other vegetation. Some species like
Agalychnis lemur
can have different coloration, such as exhibiting an orange dorsal side. All
Agalychnis
species have rather large eyes that protrude from their craniums. Their limbs are
long and some have webbing between their toes.
Geographic Range
Agalychnis
's range is limited to the Neotropical region, inhabiting areas in central and northern
South America.
- Biogeographic Regions
- neotropical
Habitat
Agalychnis
are found in the tropical forests of Central America and the northwestern regions
of South America. They are arboreal animals, so they are found in tree canopies. This
limits them to forests and wetlands where there is plenty of coverage from predators
and ample vegetation to lay their eggs and/or seek shelter.
Agalychnis
are found around ponds during the mating season where they lay their eggs. These
frogs rarely venture to the ground but do so for mating and spawning reasons.
- Habitat Regions
- tropical
- terrestrial
- freshwater
- Terrestrial Biomes
- forest
- rainforest
- Aquatic Biomes
- lakes and ponds
- Wetlands
- swamp
Systematic and Taxonomic History
With our current understanding of
Agalychnis
, they are most closely related to genus
Phyllomedusa
.
Agalychnis
used to be known as
Pachymedusa
.
Physical Description
Agalychnis
frogs have webbing in-between each of their toes and suction disks at the ends of
their digits. Body-color ranges anywhere from light green to dark green on the dorsal
side. Some frogs are even able to exhibit metachrosis (i.e.
Agalychnis lemur
) wherein they change from a green color during the day into reddish-brown or even
orangish-tan at night. On their ventral side, they can have many different yellow,
white, or orange shades. Their size can range anywhere from 30mm-88mm. Their appendages
are long and slender, with a slender, flattened body and a depressed head. Their eyes
are rather large and protrude out of their heads, which have lower eyelids. Most of
these frogs' skin, both ventrally and dorsally, is smooth but some have rough warts.
Agalychnis
frogs' heads are round and they have a short snout when looked at from above.
- Other Physical Features
- ectothermic
- bilateral symmetry
- Sexual Dimorphism
- female larger
Development
- Development - Life Cycle
- metamorphosis
Reproduction
Agalychnis
frogs' main source of attracting and finding mates is acoustic communication. Males
have many different types of calls to attract a female. They can enforce territorial
defense or make their location clear through different calls. Their aggressive calls
are used to deter other males from trespassing their territory. Females can choose
their mates through the differences in their mating calls.
- Mating System
- polygynandrous (promiscuous)
Agalychnis
frogs can lay anywhere from 14-67 eggs (i.e.
A. spirrelli
) to 47-162 eggs (i.e.
A. annae
) in a single clutch. Eggs then hatch into tadpoles around 6-14 days after being laid.
Some species show plasticity while hatching.
A. callidryas
can undergo synchronous hatching when disturbed by predators or fungus. These tadpoles
then develop in pools of water, where they are laid in leaves that overhang the water
body. They are then independent of their parents, and the ones that survive undergo
metamorphosis to transition to terrestrial life.
In
Agalychnis
, there is little to no parental investment. After the female lays her eggs, they
are left on their own to fend for themselves.
- Parental Investment
- no parental involvement
Lifespan/Longevity
Agalychnis
frogs have been known to live as long as 4-8 years or more.
Behavior
Agalychnis
are primarily nocturnal frogs. Their croaks can be heard during the mating season,
especially at night. These frogs exhibit many calls to attract mates and defend their
territory. They can produce advertisement calls or aggressive calls. Males will fight
each other to obtain a mate. They will even lay on top of females until the females
have found an appropriate spot to lay their eggs. They then lay their unfertilized
eggs either in leaves with a readily available source of water or leaves that overhang
a body of water. Some frogs in this genus, like
A. callidryas
have bright red eyes that can spook predators when opened, potentially giving the
frogs enough time to escape.
- Key Behaviors
- arboreal
- nocturnal
- motile
- territorial
- social
Communication and Perception
Agalychnis
frogs are social and have different croaks/calls with varying lengths or pitches
to communicate location, territory, and mating rituals. They also rely on their vision
to scan the environment for mates and predators.
A. callidryas
have also been observed to use vibration-based communication when males have territorial
disputes. Specifically, one male will vibrate tree branches until the submissive male
gives up that territory to the victorious male.
- Other Communication Modes
- choruses
- vibrations
- Perception Channels
- visual
- acoustic
- vibrations
Food Habits
Agalychnis
frogs are carnivorous and feed nocturnally. They are mainly insectivorous, preying
on small insects but also smaller frogs and vertebrates. Soft-bodied invertebrates
like crickets, flies, and moths make up a majority of their diet. The tadpoles of
Agalychnis
frogs also prey on smaller insects like crickets and fruit flies.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- insectivore
Predation
As these frogs are nocturnal, they have nocturnal predators as well. Notable predators
of
Agalychnis
frogs are bats, snakes, and birds. Since
Agalychnis
frogs are arboreal and live on the leaves of trees, they are easily preyed upon by
these animals, often being snatched up in an instant. However, as tadpoles, they have
even more predators to worry about before they transition into their terrestrial lives.
Fish are the biggest predators of
Agalychnis
frogs. Dragonflies and water beetles are also dangerous predators. The tadpoles'
green colors do give them some camouflage, however, hiding them in the leaves of the
canopy.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Agalychnis
frogs are biological indicators for changes within their environments. Since they
have permeable skin, these frogs are easily influenced by environmental alterations
earlier than most organisms. When an environment changes negatively, this effect can
be seen in
Agalychnis
frogs almost immediately. Thus, researchers can use them to make predictions about
the state of the environment that they are in.
Agalychnis
frogs also eat a lot of invertebrates, so they help manage insect populations and
prevent the spread of disease as well.
Economic Importance for Humans: Positive
Humans can use
Agalychnis
frogs to determine the health status of their environments. Since they are sensitive
to changes in the environment, it is easy to tell how well an ecosystem is doing by
studying these frogs.
Agalychnis
frogs also control insect populations, which consequently reduces the spread of disease.
A. callidryas
is also very popular in the pet trade. Their bright colors make them a popular animal
for people to want in their homes.
- Positive Impacts
- pet trade
- controls pest population
Economic Importance for Humans: Negative
There are no known adverse effects of Agalychnis on humans.
Conservation Status
The conservation status of
Agalychnis
is Least Concern. However, the populations of this genus are declining. This is because
of the expansion of infrastructure, logging, and agricultural activities.
Agalychnis
frogs populations are also declining because of their popularity in the pet trade,
especially
A. callidryas
. This genus is also found in many protected areas of wilderness.
Additional Links
Contributors
Josh Dresen (author), Colorado State University, Audrey Bowman (editor), Colorado State University, Sydney Collins (editor), Colorado State University.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- freshwater
-
mainly lives in water that is not salty.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- rainforest
-
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
- swamp
-
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- choruses
-
to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- pet trade
-
the business of buying and selling animals for people to keep in their homes as pets.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
References
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Grover, M. 2022. "Reptiles" (On-line). What Eats A Red-Eyed Tree Frog. Accessed March 06, 2022 at https://everythingreptilion.com/what-eats-a-red-eyed-tree-frog/ .
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