Description
Leptopelis anebos is a small- to medium-sized frog species with a snout-vent length of 31.9 - 38.9 mm in males. The single female specimen described had a snout-vent length of 48.7 mm. The head is flat and wider than the body, and the body is slender. The snout is short and appears rounded from the lateral view. The nostrils are visible from the top. The eye is relatively large, and its size is about 1.5 times larger than the distance between the eye and the nostril. The tympanum is obvious, and its horizontal diameter is slightly more than half the eye diameter. The skin is finely granular and has a few larger tubercles on the top. The skin on the underside is granular. The pectoral glands are present on the underside. The hands are one third webbed. The outer metatarsal tubercle is absent, and the inner metatarsal tubercle is small and ovoid. The palmer tubercles have well-developed subarticular tubercles under each finger. The discs of the fingers are about 1.5 times the width of the phalanges. The relative finger lengths are I < II < IV < III. The feet are one half webbed. The tibia is a little more than half snout-vent length. The outer metatarsal tubercle is absent, and the inner metatarsal tubercles are well-developed. Round subarticular tubercles can be found under each toe. The discs of the toes are round and are each about 1.5 times wider than the width of the phalanges. The relative lengths of the toes are I < II < III < V < IV (Portillo and Greenbaum 2014).

Leptopelis anebos is most distinct from other Leptopelis due to lacking heel spurs, having obvious subocular marks, and having complete toe webbing. Leptopelis karissimbensis may be more gray or reddish brown on the back (cream or tan in L. anebos). It also has smaller tibia and feet and a lower-frequency advertisement call. Further, L. karissimbensis occurs in high elevation forest edges, meadows, and swamps. Leptopelis modestus is restricted to the Cameroonian highlands. It also has a green or blue vocal sac (gray in L. anebos), and has a brown back. Leptopelis fiziensis has an advertisement call of 2 - 3 clacks or pulses per call (1 clack/pulse per call in L. anebos) and its back can be brown, dark grayish-brown, or tan. Furthermore, L. fiziensis inhabits low to mid elevation transitional forest (Portillo and Greenbaum 2014).

In life, L. anebos has a grayish-cream back, and the round dorsal tubercles are black or brown. There are cream flecks scattered on the back. Behind the eyes, there is a diffuse, indistinct brownish reticulate pattern. The iris is brown with a fine black reticulation. The area between the eye and the snout tip is light brown-gray. There is a rectangular cream blotch just below the eye that is slightly wider where it touches the lip than where it touches the eye. The tympanum is the same color as the back. The underside is white, and the sides are grayish-blue. The vocal sac is gray (Portillo and Greenbaum 2014).

In preservative, the back is a uniform brown. There are three slightly visible, brownish bands on the arms and four gray bands on the legs. There are small white blotches on the sides. The tubercles on the back are brown or black. The vocal sac is a brownish-gray (Portillo and Greenbaum 2014).

The tympanum can be more oval than round in some individuals. Some of these frogs may have more or less distinct dark brown to black spots on the back with or without grayish-brown bands. The white spots on the back may not be present. Some individuals may have more distinct dark brown bands on the top of the limbs. Some individuals may also have a distinct triangular, dark brown pattern between the eyes. Males are smaller than females, but this requires further verification as only one female has been collected (Portillo and Greenbaum 2014).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Congo, the Democratic Republic of the

	View distribution map in BerkeleyMapper.
	View Bd and Bsal data (1 records).

The species is known from only one locality in the montane forests of the Itombwe Plateau, located in the Albertine Rift in East Africa, at elevations between 1897 - 2227 m. This locality near Tumungu, Democratic Republic of the Congo, consists of montane grassland and forest (Portillo and Greenbaum 2014).

Life History, Abundance, Activity, and Special Behaviors
The frogs are found 1 - 2 m above the ground in plants and trees with streams nearby. The adult female was collected from Bilimba near a stream in savanna, 500 m from montane forest (Portillo and Greenbaum 2014).

The advertisement call is a single-pulsed clack that sounds like “quack” to the human ear. They call at night. The repetition is constant, and the call lasts an average 0.21 seconds. The time between calls is about 3.48 seconds. The frequency for the call is between 1.74 - 2.18 kHz (Portillo and Greenbaum 2014).

Trends and Threats
While the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), was found in localities on the Itombwe Plateau, it was not found near Tumungu, where the only known locality of L. anebos is found. It was also not found in samples of this species. There is a high prevalence for Bd in the Albertine Rift; 34.9% of frogs surveyed were found to have a Bd infection (Greenbaum et al. 2015).

The landscape of the Itombwe Plateau is being threatened by deforestation and fragmentation due to agriculture, logging, mining, and ranching. The habitat quality and quantity is declining, so it is likely that the population is also declining (IUCN 2016).

Possible reasons for amphibian decline

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

Comments
The species authority is: Portillo, F., Greenbaum, E. (2014). “At the Edge of a Species Boundary: A New and Relatively Young Species of Leptopelis (Anura: Arthroleptidae) from the Itombwe Plateau, Democratic Republic of the Congo.” Herpetologica, 70(1), 100-119.

Maximum likelihood analysis and Bayesian inference of 16s, cyt b, mitochondrial and RAG-1 nuclear DNA sequences showed this species diverged from its sister taxon, L. karissimbensi, less than 1 million years ago. Earlier, the L. fiziensis complex split from the L. karissimbensis/anebos complex and is the next closest ancestor (Portillo et al. 2015).

The specific epithet, “anebos”, comes from the Greek word “anebos” meaning “young or immature or not yet into adulthood.” It refers to the relatively young age of the new species based on the small branch lengths between it and L. karissimbensis (Portillo and Greenbaum 2014).

References

Greenbaum, E., Meece, J., Reed, K., Kusamba, C. (2015). ''Extensive occurrence of the amphibian chytrid fungus in the Albertine Rift, a Central African amphibian hotspot.'' Herpetological Journal, 25, 91-100.

IUCN SSC Amphibian Specialist Group. 2016. Leptopelis anebos. The IUCN Red List of Threatened Species 2016: e.T73785830A73785852. http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T73785830A73785852.en. Downloaded on 27 March 2017.

Portillo, F. Greenbaum, E. (2014). ''At the Edge of a Species Boundary: A New and Relatively Young Species of Leptopelis (Anura: Arthroleptidae) from the Itombwe Plateau, Democratic Republic of the Congo.'' Herpetologica, 70(1), 100-119.

Portillo, F., Greenbaum, E., Menegon, M., Kusamba, C., Dehling, J. M. (2015). ''Phylogeography and species boundaries of Leptopelis (Anura: Arthroleptidae) from the Albertine Rift.'' Molecular Phylogenetics and Evolution, 82, 75-86.

Species Account Citation: AmphibiaWeb 2017 Leptopelis anebos: Young Itombwe Forest Treefrog <https://amphibiaweb.org/species/8135> University of California, Berkeley, CA, USA. Accessed Dec 4, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 4 Dec 2024.

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