AMPHIBIAWEB
Phrynobatrachus scheffleri
family: Phrynobatrachidae
 
Species Description: Channing, A., and K. M. Howell. 2006. Amphibians of East Africa. Ithaca, New York: Cornell University Press.

Country distribution from AmphibiaWeb's database: Kenya, Tanzania, United Republic of

View distribution map using BerkeleyMapper.


Conservation Status (definitions)
IUCN (Red List) Status Least Concern (LC)
See IUCN account.
CITES
Other International Status None
National Status None
Regional Status None

   

From the Encyclopedia of Life account:

Summary

Phrynobatrachus scheffleri is a small species (SVL < 20 mm) of puddle frog distributed in Kenya and Tanzania. Members of this genus are identified by the presence of a midtarsal tubercle, elongate inner metatarsal tubercle, and outer metatarsal tubercle. P. scheffleri is characterized by rudimentary webbing and lack of digital discs. Adult males exhibit greyish brown throats with minute asperities sparsely but evenly covering the dorsum and venter. In females, asperities are restricted to the peri-anal region.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Distribution

It is widely distributed in semi-humid eastern Africa from coastal Kenya and Tanzania northwest up to the Ugandan border (Kakamega Forest). According to Channing & Howell (2006), this species may extend into Uganda. Specimens previously identified as P. scheffleri on the island of Zanzibar are most likely P. ungujae.


Authors: Zimkus, Breda; Bergmann, Travis
License: http://creativecommons.org/licenses/by-nc/3.0/

Morphology

The body is slender with the head narrower than body. Maxillary teeth are present, and vomerine teeth are absent. Tongue is as long as wide, free for about two thirds of its length, tip is bifurcated, and a papilla is present. Nostrils are closer to tip of snout than to anterior corner of eye, and the canthus rostralis is slightly concave from tip of snout to nostril and straight from nostril to eye. The horizontal eye diameter is larger than the distance from nostril to anterior corner of eye, and the tympanum is invisible. Dorsal skin is finely coarse and ventrally smooth. Manual webbing is absent. Fingertips may be slightly swollen but not expanded to digital discs. Pedal webbing is rudimentary with 3-3.5 digits free of webbing on digit IV. Toe tips may be slightly swollen but not expanded to digital discs. Dorsum is brown with semi-regular dark brown markings on each side, and a light vertebral line may be present. The upper arm is of lighter colour, the back of thighs is banded. Venter is translucent to cream, with dark marks in the pectoral region. In males the throat is greyish brown, transverse gular folds are present, and small femoral glands are visible. Minute asperities sparsely but evenly covering the dorsum and venter in males, and asperities are restricted to the peri-anal region in females. The iris is golden brown.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Size

Phrynobatrachus scheffleri is a miniature (snout–vent length < 20 mm) puddle frog species. Snout-vent length varies from 10-16.36 mm (n = 49) in males, and 13.0-19.11 mm ( n = 18) in females (Schick et al., 2010).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Diagnostic Description

Phrynobatrachus scheffleri is a small species (SVL < 20 mm) of puddle frog characterized by rudimentary webbing and lack of digital discs. Adult males exhibit greyish brown throats and small femoral glands are present. Minute asperities sparsely but evenly cover the dorsum and venter in males; asperities are restricted to the peri-anal region in females.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Comparisons

Phrynobatrachus inexpectatus, P. mababiensis (including its junior synonyms P. vanrooyeni, P. chitialaensis, P. broomi), P. minutus, P. parvulus (including its junior synonyms P. schoutedeni, P. ukingensis nyikae) and the P. kakamikro are morphologically most similar to P. scheffleri. Toe webbing in P. inexpectatus is almost absent and the throat of males is strongly suffused with dark grey pigment (Largen, 2001). Phrynobatrachus minutus and P. parvulus males in breeding condition can be distinguished by throat colour, yellowish and dark grey, respectively (versus light grey in P. scheffleri). The following can be distinguished from P. scheffleri (< 20 mm SVL) by having larger adult SVL: Phrynobatrachus acridoides (ca. 25 mm), P. auritus (> 35 mm), P. bullans (ca. 25 mm), P. dendrobates (> 30 mm), P. irangi (> 50 mm ), P. kreffti (> 35 mm), P. natalensis (> 24 mm), P. pakenhami (> 25 mm) and P. versicolor (> 25 mm). Phrynobatrachus graueri, P. kinangopensis, P. perpalmatus, and P. rouxi are of similar SVL, but display digital discs and a visible tympanum (both absent in P. scheffleri). In addition, the foot of P. kinangopensis and P. perpalmatus is well webbed (versus rudimentary webbing in P. scheffleri). Phrynobatrachus pallidus, P. rungwensis, P. ukingensis, P. ungujae and P. uzungwensis share similar SVL with P. scheffleri and exhbit an indistinct tympanum, but differ through presence of well developed digital discs (versus absence in P. scheffleri). In addition, the throat is heavily pigmented in P. ukingensis, and P. uzungwensis exhibits extensive pedal webbing (vesus rudimentary webbing in P. scheffleri). Phrynobatrachus breviceps and P. stewartae exhibit more extensive pedal webbing (at maximum two and a half phalanges of fourth toe free of webbing versus three free of webbing in P. scheffleri).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Habitat and Ecology

It is associated with both open land (savanna or farm land) and secondary forest margins (Schick et al., 2010). It is found amongst herbaceous vegetation, leaf litter, rocks or mud at the swampy margins of lakes, rivers, streams and temporary pools in both moist grassland and forest clearings (Stuart and Cox, 2008). According to Stuart and Cox (2008), it occurs up to at least 1,800m asl, while Schick et al. (2010) record that it only occurs up to 1,650 m asl.

They can be most easily found next to small streams and seepages in grassy streams, wooded areas and forest. They hop quickly about in the mud or sand at the side of the stream catching any flies or other small insects that might land there (Text from Measey et al. 2009, © SANBI).


Authors: Zimkus, Breda; Bergmann, Travis
License: http://creativecommons.org/licenses/by-nc/3.0/

Associations

This species can be confused with Arthroleptis xenodactyloides, except that it has distinctive raised marks forming a V pattern on its back (Text from Measey et al. 2009, © SANBI).

Other species known to be sympatric include Phrynobatrachus natalensis, Amietophrynus maculates, Amietophrynus regularis, Hyperolius glandicolor, Hyperolius pictus, Kassina senegalensis and Phlyctimantis keithae (Schick et al., 2010).


Authors: Zimkus, Breda; Bergmann, Travis
License: http://creativecommons.org/licenses/by-nc/3.0/

Population Biology

It is a poorly known species, and so there is little information on its abundance (Stuart and Cox, 2008).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Activity and Special Behaviors

This species is nocturnal (Schick et al., 2010).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Advertisement Call

Males call from concealed positions close to breeding sites with a series of short buzzes, ‘bzzz bzzz bzzz’ (Text from Measey et al. 2009, © SANBI).

Advertisement calls were recorded outside Nairobi, Kenya, and at Luisenga dam, Mufindi highlands, Tanzania by Schick et al. (2010). At the former site, calling and non-calling frogs were sitting on floating vegetation and at the edge of ponds or freely floating in small water bodies. Advertisement calls from both sites largely coincide and can be described as a long ‘trill’ consisting of a single note. Pickersgill (2007) described and illustrated an advertisement call for P. scheffleri from Bermi, Tanzania (1900 m above sea level), which appears to belong to a population conspecific to the Nairobi and Luisenga dam populations. Phrynobatrachus mababiensis, P. parvulus and P. kakamikro produce advertisement calls of more than one note and have lower pulse rate and higher dominant frequency.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Reproduction

It breeds in lake edges, rivers, streams and pools (Stuart and Cox, 2008).

This species lays eggs singly floating in small puddles at the edges of streams, especially those that have formed during spates of rain (Text from Measey et al. 2009, © SANBI).


Authors: Zimkus, Breda; Bergmann, Travis
License: http://creativecommons.org/licenses/by-nc/3.0/

Tadpole morphology

The tadpoles grow within the puddles and metamorphose into juveniles which can also be found at the side of the stream (Text from Measey et al. 2009, © SANBI).


Author: Bergmann, Travis
License: http://creativecommons.org/licenses/by-nc/3.0/

Phylogenetics

Mitochodrial sequence data from 12S rRNA, valine-tRNA, and 16S rRNA fragment, as well as combined sequence data from mitochondrial and nuclear (RAG-1) genes indicate that P. inexpectatus and P. minutus are the sister clade to P. scheffleri (Zimkus et al., 2010). These species fall within a larger group of puddle frogs that are endemic to East African montane regions and also includes P. keniensis, P. kakamikro, P. mababiensis (C), and P. parvulus, P. rungwensis, and P. uzungwensis (Zimkus et al., 2010).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

IUCN Red List Category and Justification of Conservation Status

Even though this species is considered somewhat poorly known, the IUCN Red List (2009) categorizes it as Least Concern given its relatively wide distribution, presumed large population, and apparent adaptability to habitat change (i.e. occurrence in farm land). The assessment notes that it is unlikely to be declining fast enough to qualify for listing in a more threatened category.


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/

Threats

It is likely to be impacted by habitat degradation, especially as a result of agricultural expansion, human settlement and overgrazing by livestock (Stuart and Cox, 2008).


Author: Zimkus, Breda
License: http://creativecommons.org/licenses/by-nc/3.0/