Description
Phrynobatrachus phyllophilus is a small, compact species of frog ranging in size from 12 - 17 mm in males to 15 - 23 mm in females. They have moderately pointed snouts, with the nostrils closer to the tip of the snout than to the eyes. The space between the eyes is more than half the width of the head. The tympanum is small but distinct. The skin is mostly smooth except for large dorsal warts along the shoulders and folds running along the throat. The fingers are unwebbed and the relative finger lengths are 1 = 2 < 3 > 4. The thumb is not swollen. Both the toes and fingers end in enlarged discs. The tibia is slightly longer than the femur and the foot is longer than both. The relative toe lengths are 1< 2 < 3 < 4 > 5. The toe webbing formula is 1 (0), 2 i/e (1-0), 3 i/e (2-1), 4 i/e (1), 5 (1). This species sports tarsal tubercles, elongate inner metatarsal tubercles, outer metatarsal tubercles, and small but distinct femoral glands (Rödel and Ernst 2002).

Laboratory hatched tadpoles at Gosner Stages 33 – 34 measured 11.0 – 11.3 mm in total length and 3.9 – 4.0 mm in body length. At Gosner Stages 37 – 41, the total length was 13.0 mm and the maximum tadpole body length was 4.7 mm. Tadpole bodies from the dorsal view are ovoid, and in the lateral view they are flattened ovals. The body is 1.7 times longer than it is wide and half the length of the tail. The laterally positioned nostrils are not visible in the dorsal view and are closer to the snout than the anterior corner of the eyes. The eyes are positioned dorsolaterally. A single row of papillae with a rostral gap borders the small anteroventral oral disc. It has long filamentous papillae on the caudal side and some additional papillae at the oral angles. The jaw sheaths are thin and shaped in a broad U. The labial tooth formula is 1:1+1/3 with a very short third row in the lower lip. The spiracle is sinistral and visible on the dorsal side. The vent is positioned basicaudally and opens medially. The tail is moderately webbed. The dorsal fin is slightly curved, 1.1 times the height of the body, and begins at the junction of the tail and body. The ventral fin is parallel to the tail axis. The tail ends in a point (Rödel and Ernst 2002).

Phrynobatrachus phyllophilus is distinguished from closely related species by its smaller size, ventral coloration, lack of eyelid tubercles, and less developed webbing. A unique characteristic of P. phyllophilus is that it is the singular species within the Phrynobatrachus genus to lay its eggs on dry leaves near small puddles of waters. Additionally, the eggs are very high in yolk content. Phrynobatrachus phyllophilus is most closely related to the species Phrynobatrachus guineensis although there are several morphological and behavioral differences between them. Phrynobatrachus phyllophilus has very few black spots on the stomach and the usual coloration of yellow hips and orange toes is absent. Reproductive males do not have swollen thumbs and their calls are more complex than P. guineensis. More specifically, from P. guineensis, the species can be differentiated by advertisement call structure, with P. phyllophilus having longer and more conspicuous calls, and from their calling perches. From P. alleni, P. liberiensis, P. natalensis, and P.plicatus, P. phyllophilus can be differentiated because the focal species has a smaller snout-vent length. Phrynobatrachus latifrons, P. accraensis, P. francisci, P. natalensis, P. alleni, and P. plicatus all have more webbing than P. phyllophilus. Phrynobatrachus calcaratus, P. villiersi, P. taiensis, and P. annulatus have a eyelid tubercle that is absent in P. phyllophilus. Phrynobatrachus ghanensis, P. villiersi, P. annulatus, P. fraterculus, and P. guineensis have different ventral coloration than P. phyllophilus. And lastly, male P. alleni, P. accraensis, and P. latifrons have yellow throats and male P. phyllophilus do not (Rödel and Ernst 2002).

In life, adults are beige to dark brown on the dorsum. They sport dorsal warts ringed in brown and black lateral bands that begin behind the tympanum and end in front of the hips. Black and white bars decorate the upper and lower jaws. Spots colored white, yellow, yellow with a red center, or red may appear on the flanks above the lateral bands. The spots may extend to the eyes. There is a black spot just anterior to the hips, and a black transverse bar on the femur, tibia, and toes. The ventral parts of the femur and tibia are dark gray as are the tips of the digits. The knees and border of the tibia are black. There is a black border around the anal region. The throat is black and the pectoral region and belly are white. The pectoral region may have small black spots on the sides. In preserved specimens, the yellow and red spots on the flanks become faded, and the dark gray coloration on the femur and tibia fades to a light, pale gray (Rödel and Ernst 2002).

In life, tadpole bodies are uniformly brown with a slightly lighter ventrum. The tail fin is translucent and lightly speckled with small dots. In preserved specimens, the color around the eyes and tip of the snout fade to a lighter brown color (Rödel and Ernst 2002).

Females are much larger than males. The texture of the skin can vary between individuals and within an individual over time. This appears to be hormonal as the skin is normally smooth in reproductive males. Non-reproductive males have white throats with some black spots and females have white to gray throats with more black spots or patches. There is variation in the color and size of the spots on the flanks and, while rare, there may be a second or third transverse line along the femur and tibia. There is variation in the distinctiveness of the outer metatarsal tubercle. Based on geography, the species may have different advertisement call frequency ranges (Rödel and Ernst 2002).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Cote d'Ivoire, Guinea, Liberia, Sierra Leone

View distribution map in BerkeleyMapper.

Phrynobatrachus phyllophilus is found in the Western part of the Upper Guinean rainforest as well as in Sierra Leone, Liberia, and South-Western Ivory Coast. This species is also thought to be located in Eastern Ivory Coast and Western Ghana, however, there is minimal research to support this (Rödel and Ernst 2002). Ideal habitat for P. phyllophilus is dense, swampy areas near the rainforest floor. This species can be found among leaf litter and prefers low temperatures and high humidity (Rödel and Ernst 2002, Kouame et al. 2014). The elevation distribution of these species is assumed to be up to 1000 meters above sea level (Rödel 2004).

Life History, Abundance, Activity, and Special Behaviors
The primary habitat of the “Near Threatened”, diurnal, P. phyllophilus is composed of swampy forest areas with a clear understory, but with a noted preference to fully covered canopy and abundant leaf litter covering the majority of the habitat. In the months outside of the rainy season P. phyllophilus concentrate in areas around dry riverbeds, often centralized around small puddles (Rödel and Ernst 2002).

Males call from under leaves near small puddles, less than 1 m² and a few cm deep, on the forest floor. Males will also form choruses initiated by a single male. Of 164 calls observed only 11 males were made between 7 p.m. and 10 p.m. This would suggest that the species is largely diurnal. Additionally, half of the calling males were active during the month of June though calling behavior was recorded from May to November. This suggests that the primary breeding season is during the rainy season (Rödel and Ernst 2002).

The advertisement calls of four males were analyzed more thoroughly. An introductory call, lasting up to 8 seconds, consisted of multiple series of 1 – 3 short, metallic clicks followed by a longer note. Each series lasted 0.44 – 0.75 seconds. The shorter notes had 6 - 7 pulses that lasted 0.04 seconds. The longer note had 21 – 32 pulses and lasted 0.21 – 0.32 seconds. The introductory call was followed by a longer sequence of notes that lasted 0.04 – 0.06 seconds and had 5 – 10 pulses. This series lasted 8 – 10 seconds. Inter-note durations in the second sequence lasted 0.10 – 0.13 seconds. A final sequence lasted 0.17 seconds and consisted of 20 pulses. The full call frequency ranged from 3500 – 6083 Hz. The maximum frequency intensity was 4500 – 5000 Hz. The call may have a lower frequency in Sierra Leone (Rödel and Ernst 2002).

Prior to laying eggs, the species performs axillary amplexus. Females then lay eggs with high yolk content on dry leaves near small puddles of waters. Eggs require moisture but will not survive submersion (Rödel and Ernst 2002).

In a captive environment breeding pairs deposited clutches of up to 34 eggs on dry leaves, which then took between 9 - 10 days to embryonically develop. Tadpoles reached Gosner Stages 33 – 34 after five days and reached Gosner stages 37 – 41 after 18 days. Further metamorphosis in the juvenile stage took approximately 3 weeks and metamorphs measured about 5.0 mm. There does not appear to be any parental care (Rödel and Ernst 2002).

Trends and Threats
Phrynobatrachus phyllophilus is listed as “Near Threatened” by the IUCN Red List. While it is considered a common species in its home range, its population is decreasing. Threats to the population include habitat loss due to agricultural development. Additionally, mining is also contributing to population loss in the species (Rödel 2002).

This species is not generally consumed or collected by humans. It is affected mainly by habitat loss from human activities such as logging (Rödel and Bangoura 2004).

The species is not considered fragmented and some portions of the range include protected areas such as the Mount Nimba World Heritage Site in Cote D’Ivoire, Guinea and Liberia (Rödel and Ernst 2002).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Urbanization
Mining
Habitat fragmentation

Comments
The species authority is: Rödel, M.-O., Ernst, R. (2002). “A New Phrynobatrachus from the Upper Guinean Rain Forest, West Africa, including a Description of a New Reproductive Mode for the Genus”. Journal of Herpetology, 36(4), 561-571.

Phrynobatrachus phyllophilus is most closely related to the species Phrynobatrachus guineensis (Rödel and Ernst 2002).

The species epithet, “phyllophilus,” came from two Greek words: “phyllon” meaning “leaves” and “philein” meaning “loving.” Phrynobatrachus phyllophilus is named because this species is leaf loving, spending a lot of time in the leaf litter of rainforest floors. Leaves are an important part of this frog’s life cycle because males only call when sitting under leaves and the female lays eggs on the leaves (Rödel and Ernst 2002).

References

Kouamé N.-G., Konan J., Adepo-Gourène A.-B., Gourène G., Rödel M.-O. (2014). ''The amphibians of the Yakassé-Mé village forest, a threatened rainforest of South-Eastern Ivory Coast.'' Herpetology Notes, 7, 657-665.

Rödel, M.-O. 2004. Phrynobatrachus phyllophilus. The IUCN Red List of Threatened Species 2004: e.T58134A11739175. Downloaded 17 February, 2017.

Rödel, M.-O., Bangoura, M. A. (2004). ''A conservation assessment of amphibians in the Forêt Classée du Pic de Fon, Simandou Range, southeastern Republic of Guinea, with the description of a new Amnirana species (Amphibia Anura Ranidae).'' Tropical Zoology, 17(2), 201-232.

Rödel, M.-O., Ernst, R., (2002). ''A New Phrynobatrachus from the Upper Guinean Rain Forest, West Africa, including a Description of a New Reproductive Mode for the Genus.'' Journal of Herpetology, 36(4), 561-571.

Species Account Citation: AmphibiaWeb 2018 Phrynobatrachus phyllophilus <https://amphibiaweb.org/species/6665> University of California, Berkeley, CA, USA. Accessed Nov 25, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 25 Nov 2024.

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