Description
Breviceps bagginsi is a fossorial microhylid frog with a snout-vent range of 20.0 – 25.9 mm. The snout is highly truncated. The pupil of the eye is horizontally elliptic and the tympanic is indistinguishable. The limbs are short. The fourth finger is shorter than the third, reaching the undivided subarticular tubercles of the third finger. Inner and outer tubercles of the foot are divided by a deep gap. The outer fifth toe is extremely small, not even reaching the basal subarticular tubercale on the fourth toe. The vent is terminal. The skin of the dorsum has many large, scattered tubercles that each contains openings for 2-6 dermal glands. The tubercles are pigmented with small, dark speckles. The ventrum is smooth (Minter 2003).

Breviceps bagginsi is sympatric with B. verrucosus and possibly sympatric with B. mossambicus, B. adspersus, and B. sopranus, but can be differentiated from them by its call (see Life History Section). Breviceps bagginsi can be further differentiated from B. verrucosus by the former being smaller, having a less densely granular dorsum, and a having a smooth venturm. Breviceps adspersus is smaller than B. bagginsi and has a much shorter fourth finger. Breviceps bagginsi can be differentiated from B. mossambicus and B. sopranus by the two latter having approximately equal lengths third and fourth finger (Minter 2003).

In general, the dorsum of the body and limbs are medium to dark brown in color dotted with darker speckles. The dorsum is further marked with a lighter bar between the eyes, paravebral patches, and three dorsolateral patches. In life, the dorsum appears dark chocolate-brown with the patches being a lighter brown color. Breviceps bagginsi has broad strips on the head and neck region - black lines that run along the lower eye down to the base of the arm and a white stripe that runs from the middle of the lower eyelid to the corner of the mouth and long the lips. At the posterior gular patch the lip line becomes indistinct and mottled. The anterior gular patch is black. The sides of the body between fore and hind limbs are brown with white speckles. The pectoral and ventrum are a pure white (Minter 2003).

Dorsal color and markings are highly variable including variation in the distinctness of the interocular bar, a light line from heel to heel, variation in distinctness of paravertebral patches, variation in degree of fusion of dorsolateral patches, continuousness of the black bar that extends from the eye to the arm, and speckles present on the abdomen (Minter 2003).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: South Africa

View distribution map in BerkeleyMapper.

Breviceps bagginsi can be found in south-eastern South Africa in the Kwazulu-Natal midlands at elevations of 25 to 1400m. Breviceps bagginsi can often be found in grasslands at the edges of wood plantations. The original collection of this species occurred at grassy verges of the road on clay loam and was found in undisturbed grasslands at Mkambati (Minter 2003; SA-FRoG 2010).

Life History, Abundance, Activity, and Special Behaviors
Breviceps bagginsi species is an uncommon terrestrial frog that can be found in low abundances of 20-30 individuals at each site. Distance between sites also makes it unlikely that dispersal is taking place between sites within a generation (SA-FRoG 2010).

Breeding takes place in spring and early summer. Males call from the surface or from shallow depressions concealed beneath vegetation. The call consists of two bouts of seven to nine short, pulsed notes lasting approximately 3.8 seconds in total at a frequency of 2540 – 3042 Hz. In wet weather, calling continues throughout the day and males will continue to call from well-concealed sites in full sunlight at ambient temperatures as high as 28°C. Amplexus and oviposition have not been observed (Minter 2003). It is believed that this species is a direct developer in subterranean nests (SA-FRoG 2010)

During the emergence of termite alates, individuals leave their hiding places to feed in the open (Minter 2003).

Trends and Threats
Breviceps bagginsi is listed as Vulnerable because it has a small and declining Area of Occupancy (around 1,100 km2), and Extent of Occurrence (11,000 km2) with declining habitat quality. Additionally, the subpopulations are highly fragmented make dispersal unlikely. Construction, maintenance of roads, sylviculture, and general habitat degregation are believed to be the main threats to this species (SA-FRoG 2010).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Urbanization
Disturbance or death from vehicular traffic
Habitat fragmentation

Comments
Breviceps bagginsi species is named in honor J.R.R. Tolkien’s The Hobbit after the title character, Bilbo Baggins (Minter 2003).

References

Minter, L. R. (2003). Two new cryptic species of Breviceps (Anura: Microhylidae) from southern Africa. African Journal of Herpetology . 52, 9-21.

Phaka, F.M., Netherlands, E.C., Kruger, D.J.D., Du Preez, L.H. (2019). Folk taxonomy and indigenous names for frogs in Zululand, South Africa. J Ethnobiology Ethnomedicine 15, 17. [link]

South African Frog Re-assessment Group (SA-FRoG), IUCN SSC Amphibian Specialist Group, 2010. Breviceps bagginsi. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. Downloaded on 15 May 2013.

Species Account Citation: AmphibiaWeb 2023 Breviceps bagginsi: Bilbo's Rain Frog <https://amphibiaweb.org/species/6246> 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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