AMPHIBIAWEB
Phrynobatrachus ruthbeateae
family: Phrynobatrachidae
 
Species Description: Roedel M-O, Doherty-Bone T, Kouete MT, Janzen P, Garrett K, Browne R, Gonwouo NL, Barej MF, Sandberger L 2012 A new small Phrynobatrachus (Amphibia: Anura: Phrynobatrachidae) from southern Cameroon. Zootaxa 3431: 54-68.

© 2012 Dr. Peter Janzen (1 of 5)
Conservation Status (definitions)
IUCN (Red List) Status
CITES No CITES Listing
Other International Status None
National Status None
Regional Status None

 

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Description
Phrynobatrachus ruthbeateae is a small frog with a small oval, compact body with a black lateral face mask, absent eyelid cornicle but with large warts on the upper eyelids, scapular ridges converging in a straight line, dorsal skin that is lightly granular to smooth, large white warts on the flanks, white belly, yellow groin area and lower thighs, distinct fingertip and toetip discs, and well developed webbing. Mature males have a snout-vent length of 17.2-17.8 mm and mature females can have a snout-vent length of up to 19.7 mm. This species has a short, round snout when viewed from above and from the side, as well as a rounded canthus. The loreal region is straight, and the head directly behind the eyes has a width of 6.3 mm. The laterally positioned eyes are medium sized (2.8 mm diameter) and lie 1.5 mm away from the nostrils. The nostrils, also laterally positioned, are small and round and are 1.0 mm away from the snout tip. Phrynobatrachus ruthbeateae has an internarial distance of 2.1 mm and an interorbital distance of 2.2 mm. Its pupils are round and the supratympanal ridge extends from the posterior corner of the eye to the base of the forearms; the tympanum is found and indistinct with a diameter of 1.0 mm. Its upper and lower maxillae and praemaxillae have minute teeth hidden by its lips; it lacks vomerine teeth. This species has a heart-shaped tongue with a distinctly notched tip; the anterior attachment of the tongue has median papilla. The choanae is small and round. It has slender forelimbs: the upper arm is 4.0 mm and the lower arm is 3.4 mm. The hand to the tip of the third finger has a length of 4.6 mm; the carpal tubercles are large and the inner hand is oval-shaped while the outer hand is round. There are no carpal glands. The fingers have small, round subarticular tubercles and there are no other tubercles on the hands. Fingers 2 and 4 are the same length, and finger 3 is the longest. There is no manual webbing, and the fingertips are broadened to form small discs. The thumb (finger 1) is slightly swollen without distinct nuptial pads. The hind limbs are also short and slender: the femur is 8.5 mm and the tibia is 8.9 mm. The tibia length is equal to roughly one half the snout-vent length, and the foot including the longest toe is 12.3 mm. There are no glands on the thighs, but this species has tarsal tubercles. There is a long and narrow internal metatarsal tubercle 1.0 mm in length (approximately 2/3 the length of finger 1) and a small round metatarsal tubercle. The relative toe length, in ascending order, is 1, 2, 3 ,4. The digits have well-developed basal webbing (toe 1: 0.5 mm; tow 2: 1.0 mm; toe 3: 1.5 mm; toe 4: 2.5-3.0 mm, toe 5: 1.0 mm). The skin fringes extend toward the tips of the toes, which are enlarged discs (Rödel et al. 2012).

Sexual Dimorphism: Female Phrynobatrachus ruthbeateae have thinner fingers than males, with more conspicuous finger discs. Females are also black on the back and upper part of the head; they have a dorsal pattern with beige flanks whereas males have a uniformly light brown to reddish brown dorsal pattern. Females have extended scapular ridges along the dorsolateral line, a white and smooth throat, uniformly black lower mandibles, and no spines on the throat. Males can be distinguished by their black throats with large black spines anteriorly; they have an almost uniform brown to reddish brown dorsal pattern (Rödel et al. 2012).

Diagnosis: Phrynobatrachus ruthbeateae can be distinguished from other members of the Phrynobatrachus subgenus by its small body size (<20.0 mm), white belly, short shanks, lack of nuptial pads in breeding males, presence of black spines and skin folds on male throats, uniformly black mandible in females, developed pedal webbing, convergence of the scapular ridges in a straight line, dorsal ridges, distinct but less developed webbing, black vocal sac in males, and visible tympanum (Rödel et al. 2012).

Coloration in life: Phrynobatrachus ruthbeateae is a basic beige brown color on the top of the head, upper flank, and the back and top surfaces of the limbs. The tops of the feet are brown-orange. A black lateral face mask extends from the tip of the snout to the bases of the forearm; a lateroventral black band continues below the arms to the groin region. There is a blurred, dark band in the posterior part of the interorbital space; a more narrow, light band lies between the eyelids, anterior to the blurred, dark band. Phrynobatrachus ruthbeateae has black pupils surrounded by one lighter, red-golden ring, and the irises are golden. The top of the right thigh has five dark cross-bars and the top of the left thigh has four. The right shank has four dark cross-bars and the left has three. The posterior part of the top of both thighs is uniformly dark brown. A broad black triangle surrounds the vent and extends toward the belly. The throat is black and the pectoral region is white with a few small black points. A black ventrolateral band borders the white belly. The undersides of the lower arms are black, while the undersides of the forelimbs are gray. Phrynobatrachus ruthbeateae is yellowish to orange in the groin area and the lower surfaces of the thighs; a black line borders the lower part of the thighs anteriorly and the undersides of the feet are dark brown (Rödel et al. 2012).

Coloration in preservation (ethanol after almost two years): The specimen's pattern is subtlety fainter. The scapular ridges are no longer visible and the dorsal skin is smooth (Rödel et al. 2012).

Variation: Male Phrynobatrachus ruthbeateae can have a snout-vent length of 17.2-17.8 mm. Rödel et al. 2012 reports a snout-vent length variation of 13.3-19.7 mm in females, but the authors are not sure if this range includes the snout-vent length of juvenile specimens. The irises can be golden, red, or dark gray in color and the top of the skin can vary from granular to slightly warty (Rödel et al. 2012).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Cameroon

 

View distribution map using BerkeleyMapper.
Phrynobatrachus ruthbeateae is found in the leaf litter of almost undisturbed rainforests in south-eastern Cameroon. They mostly live in swamps and experience about 1700 mm annual rainfall. Phrynobatrachus ruthbeateae is thus far known only from its type locality but likely is more widespread in lowland rainforest, speculated to occur south of the Sanaga River. Without further evidence, the authors suggest an IUCN classification of Data Deficient (Rödel et al. 2012).

Life History, Abundance, Activity, and Special Behaviors
Male Phrynobatrachus ruthbeateae call during the day while concealed underneath leaves. The calling males sit near small puddles, where they breed, and individuals are spaced very far apart from each other. The calls are comprised of a fast series of brief metallic clicks, and sound almost identical to the call of Phrynobatrachus phyllophilus (Rödel et al. 2012).

Comments
This species is named for Ruth-Beate Rödel, the mother of the first author to describe this species (Rödel et al. 2012).

References

Rödel, M.-O., Doherty-Bone, T., Kouete, M.T., Janzen, P., Garrett, K., Browne, R., Gonwouo, N.L., Barej, M.F., Sandberger, L. (2012). ''A new small Phrynobatrachus (Amphibia: Anura: Phrynobatrachidae) from southern Cameroon.'' Zootaxa, 3431, 54-68.



Written by Amanda D. Wong (amandawong1992 AT gmail.com), Museum of Vertebrate Zoology, UC Berkeley
First submitted 2012-09-28
Edited by Michelle S. Koo (2012-10-21)

Species Account Citation: AmphibiaWeb 2012 Phrynobatrachus ruthbeateae <http://amphibiaweb.org/species/7894> University of California, Berkeley, CA, USA. Accessed Jun 23, 2017.



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Citation: AmphibiaWeb. 2017. <http://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 23 Jun 2017.

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