Geographic Range
This is very rare species of frog.
Rana okaloosae
is found in only a small area of western Florida (Okaloosa, Santa Rosa, and Walton
counties). It is "associated with small tributary streams of East Bay, Shoal, and
Yellow rivers."
Habitat
This species lives in or near shallow, nonstagnant seeps with somewhat acidic water
(pH 4.1-5.5). It's also found along shallow, boggy overflows of larger seepage streams.
It is often associated with black titi and Atlantic white cedar.
- Habitat Regions
- temperate
- terrestrial
- freshwater
- Terrestrial Biomes
- forest
- Aquatic Biomes
- rivers and streams
- Wetlands
- bog
- Other Habitat Features
- riparian
Physical Description
Males are 34.8-45.8 mm long, and females are 38.2-48.8 mm long. "The species is characterized by an unspotted dorsum, distinct dorsolateral folds that do not reach the groin, and reduced webbing of the foot". The reduced webbing distinguishes Rana okaloosae from all other American congeners.
"At least three phalanges of the 4th toe are free of webbing and at least two phalanges of all other toes are free".
Rana okaloosae
has a dark green or green-brown back, a black belly and a yellow throat. It can have
lighter spots on the lower jaw.
Rana okaloosae
tadpoles have an olive brown coloration and have buff spots on the tail. The tadpoles'
ventral surfaces are marked with white spots.
- Other Physical Features
- ectothermic
- heterothermic
- bilateral symmetry
- Sexual Dimorphism
- female larger
Development
Not much is known about the development of
Rana okaloosae
. In general eggs are laid near the surface of the water in thin gelatinous masses.
The tadpoles overwinter, and they metamorphose during the following spring or summer.
The adults remain year long in the areas used as breeding habitats.
- Development - Life Cycle
- metamorphosis
Reproduction
Males call through a "series of 3-21 gutteral chucks repeated at about five notes
per second, but slowing audibly at the end." (Moler, 1992). The frog's calls are heard
from mid-April to mid-September. We have no information on the number or pattern of
matings in this species. In other species in the genus
Rana
, males attempt to fertilize the eggs of multiple females. Females may also exercise
choice, and allow several males to fertilize their eggs.
- Mating System
- polygynandrous (promiscuous)
They deposit several hundred black eggs as a surface film (in thin gelatineous masses).
Rana okaloosae
tadpoles overwinter and metamorphose the next spring or summer.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
There is no parental care in this species.
- Parental Investment
- no parental involvement
Lifespan/Longevity
We have no information on how long these frogs live.
Behavior
We have no particular behavioral information for this species. Like all frogs it hops and swims, is mobile, but not migratory.
- Key Behaviors
- saltatorial
- natatorial
- motile
- sedentary
Home Range
We have no information on the home range size for this species.
Communication and Perception
Males of this species call to females during the breeding seasone with a series of gutteral "chucks," which they repeat at about 5 notes/sec, slowing audibly at the end. There is variation in the number of notes per call, and in intervals between cals depending on conditions. The frogs also issue single quieter notes, in response to calls coming from other nearby males.
Rana okaloosae's
call is similar to
Rana virgatipes
.
- Communication Channels
- acoustic
Food Habits
We have no information on the food habits of this species. However, it probably feeds like other species of it's genus ( Rana ). In this case, then adults would be predators on small animals, mostly invertebrates like insects and spider, possibly very small vertebrates, such as other tiny frogs.
If the larvae feed like other members of the genus, then they are grazing on algae, feeding on detritus, and possibly consuming some small zooplankton.
- Primary Diet
- carnivore
- detritivore
- Animal Foods
- amphibians
- insects
- terrestrial non-insect arthropods
- zooplankton
- Plant Foods
- algae
- Other Foods
- detritus
Predation
Adults and tadpoles have patterns of skin coloration that are cryptic, making them less visible to predators. As with most frogs, adults will jump away from predators and hide in the water if they can. We have no information on which predators attack this species.
- Anti-predator Adaptations
- cryptic
Conservation Status
In "Rare and Endangered Biota of Florida," Moler describes Rana okaloosae as rare. This species was discovered in 1982 by Paul Moler, and has been located at only 23 sites, associated with small, cool, clear seepage streams. Three of these localities are based only on single specimens, so these sites probably don't support viable populations.
Residential developments in the areas where the frog lives convert streams into chains
of lakes (through a series of dams). This poses a threat to Florida's Bog Frog habitats.
So, it is important that the streams where the frogs live are protected (this can
be done through the management of streamside vegetation).
Other Comments
Not much information is available on
Rana okaloosae
, because it is limited to one small geographic location, and it is very rare. "Our
knowledge of this species is currently limited to distribution, seasonality, and some
aspects of larval life history" (Moler, 1992).
Additional Links
Contributors
Marwa Al Nasa'a (author), University of Michigan-Ann Arbor, Kerry Yurewicz (editor), University of Michigan-Ann Arbor.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- 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.
- bog
-
a wetland area rich in accumulated plant material and with acidic soils surrounding a body of open water. Bogs have a flora dominated by sedges, heaths, and sphagnum.
- riparian
-
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- heterothermic
-
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal 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.
- polygynandrous
-
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- external fertilization
-
fertilization takes place outside the female's body
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- saltatorial
-
specialized for leaping or bounding locomotion; jumps or hops.
- natatorial
-
specialized for swimming
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- acoustic
-
uses sound to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- zooplankton
-
animal constituent of plankton; mainly small crustaceans and fish larvae. (Compare to phytoplankton.)
- detritus
-
particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).
- 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.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- detritivore
-
an animal that mainly eats decomposed plants and/or animals
References
Ashton Jr, R., P. Sawyer Ashton. 1985. Handbook of Reptiles and Amphibians of Florida . Miami, Fl: Windward.
Moler, P. 1985. A new species of frog (Ranidae:Rana) from northwestern Florida.. Copeia , 1985(2): 379-383.
Moler, P. 1992. Florida Bog Frog. Rare and Endangered Biota of Florida , 3: 30-33.
Moler, P. 1993. Rana okaloosae Moler Florida Bog Frog. Catalogue of American Amphibians and Reptiles : 561.1-561.3.