Afrixalus uluguruensis

Afrixalus uluguruensis (Barbour and Loveridge, 1928)

Common Names

Uluguru Banana Frog (English)

Languages: English

Overview

Distribution

This species occurs in the Uluguru and Udzungwa mountains of Tanzania (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Etymology

This species is named for the type locality, the Uluguru Mountains of Tanzania.

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Taxonomic Notes

Pickersgill (2007) considers the populations from the Usambara Mountains to be a separate species (Afrixalus dorsimaculatus) from the Uluguru population (Harper et al., 2010).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Description

Diagnostic Description

A small to medium-sized Afrixalus. The head is broad with a short snout, and the eyes are large and protruding. The tympanum is not visible. The white dorsum is scattered with irregular darker patches, usually without forming a distinct pattern. Fingers and toes are yellow and end in expanded orange disks. Males have fine dorsal asperites, while females are smooth (Harper et al., 2010).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Size

Snout-vent lengths of males range from 21 – 25 mm, while females are 24 – 28 mm (Harper et al., 2010). The largest specimen of the type series (MCZ A-13314) is a female of 32 mm; next four paratypes, after type, 29 mm. each. The half-dozen smallest frogs are 24-25 mm. and apparently males (Barbour and Loveridge, 1928).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Morphology

Head is slightly broader than long. Snout is obtusely rounded or slightly truncated, slightly projecting, longer than the orbital diameter (reckoning snout from the anterior border of eye). Canthus rostralis is distinct but rounded; loreal region is almost vertical, very slightly concave (in young rounded and not concave). The interorbital space is one and a half times as broad as upper eyelid. The transverse orbital diameter equals the distance from the anterior border of the eye to the nostril (slightly longer in some paratypes), also the distance between the nasal openings. The tympanum is hidden (absolutely in every specimen). Fingers and toes are moderate, dilated at their tips. Fingers are about one-third (certainly less than half) webbed. Toes are fully webbed- to the bases of all the disks, though in the case of the fourth toe this is achieved only by a narrow border of web from the sub terminal joint (unfortunately this delicate, narrow, semi-transparent webbing has not been reproduced well in the accompanying figure). The tibiotarsal joint of the adpressed hind limb reaches the eye in the type and in all paratypes. Skin is smooth above and below, except on the belly and thighs, where it is granular, hardly perceptibly so on the thighs; some scarcely distinguishable granules at the commissure of the mouth (Barbour and Loveridge, 1928).

Color of male type (MCZ A-13311) in life. Above, head, back and exposed surfaces of fore and hind limbs enamel-white; a pair of black-speckled, reddish-brown flecks on anterior part of back; another pair, more dorso-laterally situated, just in front of junction of hind limbs, and a streak of similar color on each tibia; commencing on snout a black-speckled, reddish-brown network line (the interspaces being enamel-white) passes through nostril and eye and terminates on flank. It will be noticed that when the hind limbs are arranged in the normal attitude of rest, the tibial streaks form a continuation of the lateral network hnes; fingers, thighs and part of feet yellow. Below, transparent yellow except for a broad belt of enamel-white across chest. In alcohol, spots appear brown, while the enamel-white entirely disappears, the frog being flesh-coloured with minute speckes,which may be so numerous dorsally as to give a distinctly brownish appearance to the upper surface (Barbour and Loveridge, 1928).

The whole Vituri series agreed with above description except for very minor differences. Some have a third pair of spots between eyes. The Bumbuli frog, while structurally agreeing with the Vituri series and having the same appearance in alcohol, differed considerably when alive. The colouring noted in the field was as follows. Above on head, back, fore arms, tibia and edge of feet, white with patches appearing slightly rubbed and showing yellowish-green; black specks are scattered over the whole of the upper surface, including upper arm and thigh, which are yellowish; a more or less transparent, slightly greenish band from snout through nostril and eye to flank shows the black stippling more clearly; fingers and toes clear lemon-yellow. Below, transparent white, more opaque on limbs than on belly, where internal organs show through; fingers and toes lemon-yellow (Barbour and Loveridge, 1928).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Ecology

Habitat and Ecology

It is a forest-dependent species, and does not survive in degraded habitats. Its altitudinal range is not fully known, but it is a species of medium to high altitudes (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Population Biology

It is abundant where it occurs (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Trends

Populations of this species are decreasing (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Associations

The following were found in ten stomachs examined from the type series: (i) Large muscoid dipteron. (ii) Many fruit fhes (Drosophila), one adult cercopid homopteron, and several nymphal ones, (iii) Large cercopid of a different species, (iv) Cercopid bug. (v) Elater beetles, (vi) Beetle (?Lathrididae). (vii) Two chrysomelid beetles, (viii) Several beetles with long elytra, (ix) Beetle, bug and grasshopper, (x) Earwig, ant and a small neuropteran, which Mr. N. Banks considers is almost certainly Myrmelon sp. (Barbour and Loveridge, 1928).

A nematode in one of the type specimens from Vituri (Barbour and Loveridge, 1928).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Life History

Reproduction

It breeds in swampy valley bottoms and temporary pools in closed-canopy forest (Schiøtz et al., 2008). Eggs are placed on vegetation above water. Clutches are small, containing 10 - 12 eggs (Harper et al., 2010).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Advertisement Call

A quiet buzzing sound of variable duration (Harper et al., 2010).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Conservation

IUCN Red List Category and Justification of Conservation Status

The IUCN Red List (2010) categorizes this species as Endangered because its Extent of Occurrence is less than 5,000 km2, its distribution is severely fragmented, and there is continuing decline in the extent and quality of its forest habitat in the Eastern Arc Mountains of Tanzania (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Threats

The main threat is habitat loss due to agricultural encroachment, logging, and expanding human settlements. Its habitat in the East Usambara Mountains has also recently come under serious threat as a result of the activities of illegal gold miners (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Conservation Actions and Management

It might occur in the Udzungwa National Park, but there have not yet been any confirmed records (Schiøtz et al., 2008).

Author(s): Zimkus, Breda
Rights holder(s): Zimkus, Breda

Taxonomy

  • Megalixalus uluguruensis Barbour and Loveridge, 1928 (synonym)
  • Afrixalus ulugurensis — Guibé, 1948 (synonym)

References

Barbour, T., & Loveridge A. (1928).  A comparative study of the herpetological faunae of the Uluguru and Usambara Mountains, Tanganyika Territory with descriptions of new species. Memoirs of the Museum of Comparative Zoology. L(2), 85-265.
 
Channing, A., & Howell K. (2006).  Amphibians of East Africa. Comstock books in herpetology. 418 p., [24] p. of plates. Ithaca: Comstock Pub. Associates/Cornell University Press.
Harper, E. B., Measey G. J., Patrick D. A., Menegon M., & Vonesh J. R. (2010).  Field Guide to Amphibians of the Eastern Arc Mountains and Coastal Forests of Tanzania and Kenya. 320. Nairobi, Kenya: Camerapix Publishers International.
 
FileSize (kb)Uploaded
Harper_2010_1-143.pdf37642010-05-06T19:06:17Z
Harper_2010_144-320.pdf4843.62010-05-06T19:06:33Z
Barbour_Loveridge_1928_amphibians_1.pdf4976.82010-05-24T13:48:49Z
Barbour_Loveridge_1928_amphibians_2.pdf2097.92010-05-24T13:49:00Z