Description
Diagnosis: This species can be distinguished from other congeners by the following characters: large body size (SVL of 25.2 mm in the single adult specimen, a female); expanded finger discs; outer palmar tubercle heart-shaped; canthus rostralis well-defined, concave; tympanum distinct; eyes large; well-developed fingers (4) and toes (5); adult dorsal coloration beige with brown markings, with a distinctly contrasting brown loreal region; posterior thighs orange-red; small orange-red axillary spot; throat white with brown mottling; ventral coloration bluish-white; iris with numerous greenish-gold flecks.

Description: Adult female SVL 25.2 mm. Body slender. Head as wide as body. Stout mucronate when viewed from above, protruding when viewed laterally. Nares protuberant, laterally directed, closer to the tip of the snout than to the eye. Canthus rostralis distinct and concave. Lores are straight. Tympanum is rounded and distinct, with the diameter equivalent to two-thirds of the eye diameter. Weak supratympanic fold. Eyes are large. Lacks maxillary and vomerine teeth. Choanae oval-shaped. Arms slender. Fingers have large truncate discs and lack webbing. Relative finger lengths 3>4>2>1. Outer palmar tubercle cordiform-shaped. Subarticular tubercles present and rounded. Prepollex is lacking. Hindlimbs slender. Tibia of holotype 41% of SVL. Toes lack webbing. Relative toe length 4>3>5>2>1. Outer metatarsal tubercle is lacking. Inner metatarsal tubercle is oval and distinct. Dorsal skin is shagreened. Ventral skin is finely granulated at the posterior and smooth at the anterior. Throat smooth.

Coloration in Life: Beige dorsum and dorsal surface of head. Brown interorbital bar, scapular transverse brown marking, dark brown loreal region, dark brown tympanal region. White flecking below tympanum. Iris black with greenish-gold specks. Flanks grey-brown with irregular cream and white flecking and spotting. Limbs dorsally beige with irregular diffuse brown markings. Orange-red flecks in axillary region. Orange-red coloration on groin and anterior surface of thighs. Posterior surfaces of thighs orange-red. Ventral surfaces of thighs brownish coloring with violet tint and scattered orange-red flecks. Belly greyish white. Throat white with fine brown spotting.

Coloration of Juvenile: Numerous small blue spots scattered over the body. Brown dorsum with transverse black markings. Juvenile specimen with this coloration measured 9.0 mm in SVL.

Similar Species: Stumpffia be reaches a considerably larger size than than its congeners S. gimmeli, S. helenae, S. pygmaea, S. tetradactyla, and S. tridactyla (25.2 mm SVL vs. about 10-16 mm SVL). It is slightly larger than S. grandis, S. megsoni, and S. roseifemoralis (25.2 mm SVL vs. 17-24 mm SVL in the other species). Stumpffia be has distinctly expanded truncate finger discs, in contrast to S. grandis (slightly expanded discs), S. hara (slightly expanded discs), S. megsoni (slightly expanded finger discs) and S. roseifemoralis (discs not expanded). It differs in coloration (beige with brown markings) from S. grandis (reddish-brown with large dark blotches, black throat, gray-blue venter marbled with black), S. hara (lacks orange-red coloration), S. roseifemoralis (lacks orange-red axillary flecks), and S. staffordi (light brown dorsum and light brown loreal region, brown throat with white spots). Stumpffia be also differs from S. megsoni by having a head as wide as the body (vs. head narrower than the body in S. megsoni).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Madagascar

View distribution map in BerkeleyMapper.

Endemic to the Ankarana massif in northern Madagascar. Known only from a single locality within the Ankarana Special Reserve, Antsirana Province at 90 m asl. Habitat is karstic. An adult female was found on vegetation adjacent to a nearly dry rocky river bed. The juvenile specimen was found on the wall of a cave in large boulders at the edge of a temporarily dry riverbed.

Life History, Abundance, Activity, and Special Behaviors
This species is active at night. The adult female holotype was found 50 cm above the ground, sitting on a leaf of vegetation adjacent to a nearly dry river bed. The juvenile was found on large boulders that formed a small cave adjacent to a temporarily dry riverbed, approximately 20 m away from where the female was found.

The stomach contents of the female consisted of large black ants.

Stumpffia be is unusual in undergoing ontogenetic (developmental) color change, where the juvenile coloration is quite different than the adult coloration.

Trends and Threats
This species has been described recently and is known only from two specimens, an adult female and a juvenile. The type locality is within a protected area, the Ankarana Special Reserve.

Comments
The specific epithet means "large" in the Malagasy language, referring to the adult body size as compared to other congeners.

References

Köhler, J., Vences, M., D'Cruze, N., and Glaw, F. (2010). "Giant Dwargs: discovery of a radiation of large-bodied 'stump-toed frogs' from karstic cave environments of northern Madagascar." Journal of Zoology, 282, 21-38. [link]

Species Account Citation: AmphibiaWeb 2010 Stumpffia be <https://amphibiaweb.org/species/7541> University of California, Berkeley, CA, USA. Accessed Feb 2, 2025.

Citation: AmphibiaWeb. 2025. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 2 Feb 2025.

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