AMPHIBIAWEB
Altiphrynoides malcolmi
Malcolm’s Ethiopian toad
family: Bufonidae

View distribution map using BerkeleyMapper.


Conservation Status (definitions)
IUCN (Red List) Status Endangered (EN)
See IUCN account.
CITES Appendix I
Other International Status None
National Status None
Regional Status None

   

Description
Altiphrynoides malcolmi is a small, plump-bodied toad with snout-vent lengths up to 31.5 mm in females and 21.4 mm in males. Its head is slightly longer than it is wide. From the dorsal view, the snout projects beyond the lower jaw sloping down in profile. The distance from snout tip to anterior boarder of the eye is 1 ¼ the internarial distance. The distance from the snout to the nostril is less than distance from nostril to anterior border of the eye. Its lips are not flared, canthus rostralis straight with a rounded edge, and lores sloping. The paratoid glands are situated away from the eye, level with the eyelid and above where the arm inserters into the body. The glands are short and narrow with elongated ridges that merge with an interrupted longitudinal line of small and round glands extending from the upper flanks to the groin. First and second fingers are of approximately equal length. Outer palmer tubercle visible and all palmar surfaces swollen and glandular. It has single finger tubercles that are not well defined and smooth. Inner and outer metatarsal tubercles are present but the outer is more rounded and obvious. Un-tapered toes have smooth undersides and no indication of subarticular tubercles. The first toe is quite short; the length from tip to distal edge of metatarsal tubercle is very close to the length of the tubercle. Heavy webbing that extends beyond the metatarsals is present in all except the first toe, which has webbing to the distal half o the terminal phalanx. The fleshy first toe extends just past the metatarsals. A dorsolateral row of elongated glands present. The dorsum contains small and inconspicuous pustules concentrated on the flanks. No rectal glands. The appendages and ventral surfaces are smooth and glandular. In males, cornified nuptial asperities present on the upper medially surface of the proximal phalanx of the second finger and most of the medial upper surface of the thumb. The cloacal opening is sexually dimorphic with its positioning in females being posteroventral and being ventral in sexually mature males (Grandison 1978).

In life, A. malcolmi has a variable body coloration with its dorsum ranging from grey, green-grey, brown-grey, to black. Its body pattern consists of dark spots on three semi-parallel light longitudinal stripes that can range in color from pale green, pale to bright pink, to reddish. The center stripe runs along the vertebrae but does not extend past the cervical vertebrate; the other two stripes are located between the paravertebral ridge and the flanks. The spots are evenly distributed on the dorsum. The flanks are dark ranging from grey to almost black and are often bordered with a white line on the dorsal side. The ventrum is a dirty white to cream and has highly variable patterning (Grandison 1978).

When preserved, the specimen becomes grey-brown in the canthus, flanks, and paravertebral ridges. The vertebral stripe becomes gray in color. The ventrum is tan in color with a dark patch located over the vent (Grandison 1978).

Variations: The vertebral stripe is variable in length with some not reaching beyond the sacrum on the anterior side. In rare instances the stripe is completely absent. Dorsal spotting is individualistic with some lack the spotting and many others only have a few. There is also individual variation in a pale oblique or vertical temporal bar with most specimens have an indication of it. The area above the nostrils to just below the eyes is usually pale, but some individuals do not exhibit the paleness. Some rare individuals are uniform dark brown in color except for the distal parts of finger and toes, which are a pale cream color. The throat, chest, and stomach vary from cream to dark brown in color (Grandison 1978).

Larval Description: When A. malcolmi tadpoles first hatch from their egg masses they are mostly colorless with a sparse sprinkling of melanophores on their backs. Hind limb buds are well developed at hatching and eyes are black. As they age, pigment starts to form on back starting as pale grayish white over most of the body, maturing into grey-brown, and then brown. When present, the yolk sac is yellow. The mouth contains no teeth. As the tail is being reabsorbed the larvae obtain adult coloration (Grandison 1978).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Ethiopia

View distribution map using BerkeleyMapper.
Altiphrynoides malcolmi is endemic to the highlands of the Bale Mountains in Bale Province, Ethiopia at 3200 - 4000 m above sea level. The habitat ranges from Schefflera-Hagenia-Hypericum forest to Afro-alpine moorland. In low elevations, the species is found in grassy vegetation around small streams (Largen 2001).

Life History, Abundance, Activity, and Special Behaviors
Reproduction in A. malcolmi is extremely complex and a main reason for scientific interest due to their unique terrestrial larval development (Wake 1980). Breeding occurs in wet grasses surrounding streams. In the spring, males call to attract females using a low “tseep” sound that can only be heard from distances of 2-3 m. Both sexes wander in search of mates, however females are more often found stationary in the vegetation. Once a female is close, the intensity of advertisement call increases, attracting more males and females, which form the breeding site. Upon the arrival of a female, males attach themselves to her. At times, nine males may clasp the female via belly to belly inguinal amplexus to internally fertilize her. However, only one male is successful in fertilizing her eggs. Amplexus can last for extended periods of time. After fertilization, but before breaking amplexus, the female deposits 11-31 large white eggs (up to 2.6 mm diameter) encompassed by jelly-like mucus tube that is approximately 8 mm in diameter and 4.6 – 5.5 mm in length. The eggs are typically laid at the base of herbaceous vegetation on a vertical ridge, but in some instances can be found beneath logs and leaves. These areas are usually close to, but not in small pools of water. After depositing her eggs, the female leaves the site while the successful male stays with the egg mass to attract more mates. He along, with the other males, continues to breed with females that are attracted by their calls. These females deposit their eggs with the first female’s egg mass, creating a communal mass of eggs, sometimes constituting clutches from twenty females. After all of the females have laid their eggs, the communal egg masses are abandoned by all parents (Grandison 1978).

A. malcolmi tadpoles hatch and develop terrestrially in a mucus bubble. Although A. malcolmi is a direct developing species, it does much of its metamorphic development after hatching. However, it has been suggested that A. malcolmi lays neurulae, embryos that are already starting to develop a nervous system. The timing of natural A. malcolmi hatching and metamorphosis is unknown, but was estimated in a laboratory setting that had higher temperatures (20 C compared to 5 C in natural habitats) and therefore accelerated the development. In the lab, fat larvae begin to hatch about 12 days after being laid. During development, the tadpoles feed solely on a large yolk sac and are immotile. They lack tooth ridges, papillae and beaks because they are feeding on the yolk sac. They also lack external gills and spiracle due to their terrestrial orientation in the mucus. As metamorphosis progresses, the yolk sac is reduced and the larvae size becomes skinnier. About 27 - 31 days post-laying, the tadpole begins to reabsorb its tail and become more like the fatter adult form (Grandison 1978; Wake 1980).

Trends and Threats
Highly endemic, A. malcolmi is listed as ‘Endangered’ because of its limited range of less than 5000 km2 and its known occurrence being less than 500 km2 . Its endemism to such a small area of the Bale Mountains renders them particularly susceptible to extinction pressures, the primary of these pressures being deforestation and other habitat loss. It is thought that the type locality for this species is already lost to deforestation. However at least one site of occurrence in the Bale Mountains is currently protected as a National Park managed by the Ethiopian Wolf Conservation Programme (Largen 2004).

Relation to Humans
The likeliest cause of decline is not direct exploitation of the species by humans, but rather habitat loss. Rapid deforestation is due to the demands of an ever-increasing human population for firewood, timber, and cleared land for agriculture (Largen 2004).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities

Comments
Altiphrynoides malcolmi was previously named Nectophrynoides malcolmi. In 1987, the Nectophrynoides genus was constrained to include only species found in Tanzania (based on differences in reproduction); Ethiopian species previously placed under Nectophrynoides were split into two separate genera: Altiphrynoides and Spinophrynoides (Menegon et al. 2004).

References
 

Grandison, A. G. C. (1978). ''The occurrence of Nectophrynoides (Anura: Bufonidae) in Ethiopia. A new concept of the genus with a description of a new species.'' Monitore Zoologico Italiano, N.S. Supplemento, 11(6), 119-172.  

Largen, M. J. (2001). ''Catalogue of the amphibians of Ethiopia, including a key for their identification.'' Tropical Zoology, 14, 307-402.  

Largen, M. J. (2004). Altiphrynoides malcolmi. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. Downloaded on 25 February 2013.  

Menegon, M., Salvidio, S., and Loader, S. P. (2004). ''Five new species of Nectophrynoides Noble 1926 (Amphibia Anura Bufonidae) from the Eastern Arc Mountains, Tanzania.'' Tropical Zoology, 17, 97-121.  

Wake, M.H. (1980). ''The reproductive biology of Nectophrynoides malcolmi (Amphibia: Bufonidae), with comments on the evolution of reproductive modes in the genus Nectophrynoides.'' Copeia, 1980(2), 193-209.



Written by Emma Cox, Karee Rasmussen, Philip Choy, Ann T. Chang (emcox AT ucdavis.edu, kcrasmussen AT ucdavis.edu, phchoy AT ucdavis.edu, anntchang AT berkeley.edu), UC Davis & UC Berkeley
First submitted 2010-09-23
Edited by Ann T. Chang (2013-02-25)



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Citation: AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2014. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Oct 30, 2014).

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