Description
Stumpffia bishopi is a small, elongated frog described from three specimens, two of which cannot be sexed and one of which is male. The snout-vent length is between 14.2 - 16.6 mm. The head is somewhat longer than wide but is narrower than the body. In the dorsal view, the head is slightly pointed, but is pointed in the lateral view. The protuberant nostrils are directed laterally and located closer to the snout tip than the eye. The distinct canthus rostralis is straight. The loreal region is weakly oblique and concave. The eye is about twice the diameter of the tympanum and the supratympanic fold is distinct in life but not in preservative. The dorsum and ventrum are smooth and the species lacks distinct dorsolateral folds. The upper arm is slender and the lower arm is robust. The hands are about 38% of the snout-vent length and have an oval prepollical or enlarged inner metacarpal tubercle that presents as a thickening inside of the first finger. The outer metacarpal tubercle is small but distinct. The unwebbed fingers have a relative finger length of 1 < 2 < 4 < 3, with the first finger being slightly reduced and the fourth finger is only slightly longer than the second. The fingertips are not expanded, and the single subarticular tubercles are distinct. The slender hind limbs have a tibia that is 46% of the snout-vent length and a foot that is 62% of the snout-vent length. There is no outer metatarsal tubercle, but the inner metatarsal tubercle is small. The unwebbed toes have single, distinct subarticular tubercles, and a relative length of 1 < 2 < 5 < 3 < 4. There is no toe reduction. The toe tips slightly expand into discs (Rakotoarison et al. 2022).

DIAGNOSIS:

Stumpffia bishopi can be distinguished from other Stumpffia based on morphology, coloration, and call. More specifically, S. bishopi is distinguishable from S. analamaina, S. betampona, S. contumelia, S. davidattenboroughi, S. dolchi, S. froschaueri, S. larinki, S. makira, S. madagascariensis, S. obscoena, S. pygmaea, S. spandei, S. tridactyla, and S. yanniki by its larger body size. All the species listed above are less than 14 mm whereas Stumpffia bishopi is greater than 14 mm. It is distinguishable from S. betampona, S. contumelia, S. davidattenboroughi, S. dolchi, S. garraffoi, S. makira, S. miery, S. obscoena, S. spandei, S. tetradactyla, S. tridactyla, and S. yanniki by having slightly less digital reduction, having the first finger slightly reduced. Having a second finger that is slightly shorter than its fourth finger (vs having a fourth finger subequal to the second finger in length) distinguishes S. bishopi from S. angeluci, S. maledicta, S. miovaova, and S. sorata. It can be differentiated from S. analanjirofo by having a smooth dorsum instead of a tubercular. Stumpffia bishopi has a longer foot length than S. fusca (0.62 of the snout-vent length vs 0.72 - 0.78). It is distinguishable from S. psologlossa because it has relatively larger hands (hand length to snout-vent length ratio is 0.38 as opposed to 0.18 - 0.25), lacks a dark blackish mark along its flanks, and shorter calls unpulsed calls (127 - 153 milliseconds as opposed to 791 - 871 milliseconds) as opposed to distinctly pulsed calls. Stumpffia bishopi can be differentiated from S. edmondsi, S. nigrorubra and S. pardus by having no distinct coloration on its posterior shank. Black spots on the ventral surface of S. bishopi differentiate it from S. inharana. The lack of large white markings and yellowish colors on its venter in S. bishopi distinguish it from S. grandis and S. huwei, respectively. An indistinct border between the lateral and dorsal colouration in S. bishopi distinguishes it from , S. contumelia, S. davidattenboroughi, S. madagascariensis, and S. tridactyla. Stumpffia kibome, S. meikeae, S. miovaova, S. nigriubra, and S. roseifemoralis all have red color on their ventral limbs, which S. bishopi lacks. Stumpffia bishopi has an unpulsed advertisement call whereas S. kibomena has a slightly pulsed one. It varies from S. huwei, S. kibomena, S. maledita, and S. manitika in having a longer call duration (127 - 153 milliseconds vs a duration of 70 - 124 milliseconds). Stumpffia bishopi has a longer call intervals (4388 - 6355 milliseconds vs 2143 - 2289 milliseconds) and a higher frequency range of advertisement calls ranging from 3919 - 4091 Hz vs 2842-3057 Hz than S. larinki. Lastly, S. bishopi has a shorter call duration (127- 153 ms vs 179 - 198 ms) than S. angeluci and S. madagascariensis (Rakotoarison et al. 2022).

From other members of the S. hara species group, which S. bishopi is a part, S. bishopi has a significantly smaller snout-vent length than S. be, S. hara, S. megsoni, and S. staffordi (14.2 - 16.6 mm as opposed to 19.8 - 27.9 mm). Moreover, S. be, S. hara, and S. staffordi have more expanded terminal discs on the toes and fingers. Stumpffia bishopi lacks bright reddish/orange coloration on the abdomen and limbs that distinguish it from S. be and S. megsoni. Lastly, S. bishopi has a more pronounced supratympanic fold when alive plus a dark brown coloration on the chin that distinguishes it from S. hara (Rakotoarison et al. 2022).

COLORATION:

In life, the dorsal coloration of S. bishopi is various shades of brown while the ventral coloration is a burnt orange to taupe color with flecks of black and white covering it. The chin is dark brown. The dorsal hands inner half is consistently light. In the holotype there are distinct crossbands of the thighs. After 3.5 years in preservative, the color darkened. The dorsum becomes almost uniformly brown with some light gray areas where the lightest markings are. The white flecks on its venter are no longer visible, and the coloration of the entire venter is cream colored, interspersed with gray flecks (Rakotoarison et al. 2022).

VARIATION:

The coloration of this species is variable. Some individuals have distinct patterning whereas some have uniform dorsal coloration. There is slight morphological variation including the shape of the first finger among the specimens collected by Rakotoarison et al. (2022). Some of the specimens have a first finger without any sign of medial swelling whereas others have a first finger that appears short because of a swollen prepollex (Rakotoarison et al. 2022).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Madagascar

View distribution map in BerkeleyMapper.

This species is only found in Montagne d’Ambre national park in Madagascar. The park is in northern Madagascar and the species is found at high elevations of 1330 - 1480 meters above sea level. The park is primarily montane rainforest with trees that can reach 40 meters high (Rakotoarison et al. 2022).

Life History, Abundance, Activity, and Special Behaviors
This species lives in the leaf litter in high elevation rain forests in the Montagne d’Ambre national park. One of the specimens was found calling from a slightly elevated, semi-exposed perch that was next to a path. The specimens were found in the leaf litter and among rocks suggesting that this is the niche they occupy in their habitat (Rakotoarison et al. 2022).

The call of this species consists of a tonal note that is repeated at regular intervals. The quantitative intervals are as follows: note duration is 127 - 152 milliseconds, intercall intervals is 438 - 6388 ms, and the dominant frequency called at is 3919 - 4091 Hz (Rakotoarison et al. 2022).

Rakotoarison et al. (2022) wrote that they looked both during the night and the day while using playbacks of calls to assist them in locating the species. This implies that they were calling and active at all hours of the day. However, it is recommended that more research goes into their life history before that is assumed.

Trends and Threats
At the time of the species description there wasn’t much known of the species. However, since the known range of this species is so small, Rakotoarison et al. (2022) recommend that the species be listed as "Near threatened".

Comments

PHYLOGENETIC RELATIONSHIPS:

Maximum Likelihood of 16S rRNA place S. bishopi as sister to the clade formed by S. be, S. hara, S. megosoni, and S. staffordi and as a member of the S. hara species group (Rakotoarison et al. 2022).

ETYMOLOGY:

The species is named in honor of the late Phil Bishop, professor emeritus at the University of Otago, who dedicated his career to the research and conservation of amphibians. The authors of the species description said he was an inspiring and enthusiastic person who was a joy to work with (Rakotoarison et al. 2022).

References
Rakotoarison A., Glaw F., Rasolonjatovo S. M., Razafindraibe J. H., Vences M., Scherz M. D.. 2022. Discovery of frogs of the Stumpffia hara species group (Microhylidae, Cophylinae) on Montagne d’Ambre in northern Madagascar, with description of a new species. Evolutionary Systematics 6(1), 21-33. [link]

Species Account Citation: AmphibiaWeb 2023 Stumpffia bishopi <https://amphibiaweb.org/species/9509> University of California, Berkeley, CA, USA. Accessed Apr 18, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 18 Apr 2024.

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