Stumpffia bishopi, Rakotoarison & Glaw & Rasolonjatovo & Razafindraibe & Vences & Scherz, 2022

Rakotoarison, Andolalao, Glaw, Frank, Rasolonjatovo, Safidy M., Razafindraibe, Jary H., Vences, Miguel & Scherz, Mark 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), pp. 21-33 : 21

publication ID

https://dx.doi.org/10.3897/evolsyst.6.76382

publication LSID

lsid:zoobank.org:pub:EDA7BBEE-CF8F-41E5-9FFE-68B468AB8A1F

persistent identifier

https://treatment.plazi.org/id/ADEBEEB7-6801-4C60-B463-9D9BE54F0A56

taxon LSID

lsid:zoobank.org:act:ADEBEEB7-6801-4C60-B463-9D9BE54F0A56

treatment provided by

Evolutionary Systematics by Pensoft

scientific name

Stumpffia bishopi
status

sp. nov.

Stumpffia bishopi sp. nov.

Remark.

This species has not been previously listed as a candidate species in any publication.

Holotype.

ZSM 106/2018 (MSZC 0728), adult individual (sex unknown) (Figs 2 View Figure 2 - 3 View Figure 3 ), collected between 2 and 4 December 2017 in high elevation rainforest near Grand Lac on Montagne d’Ambre (12.5970°S, 049.1573°E, ca 1400 m a.s.l.), Diana Region, northern Madagascar, by A. Rakotoarison, A. Razafimanantsoa, J.H. Razafindraibe, M.D. Scherz, O. Randriamalala, R. Tiavina, and S.M. Rasolonjatovo.

Paratypes.

ZSM 107/2018 (MSZC 0730), an adult male, with the same collection data as the holotype but collected at 12.5995°S, 049.1592°E, ca 1330 m a.s.l. (Fig. 3 View Figure 3 ); and UADBA-A 60224 (ex- ZSM 108/2018; MSZC 0741), an unsexed adult with the same collecting data as the holotype, but collected at 12.5965°S, 049.1521°E, ca 1480 m a.s.l. (Figs 2 View Figure 2 , 3 View Figure 3 ).

Diagnosis.

A moderately small species of Stumpffia from high elevation of Montagne d’Ambre in northern Madagascar. It is assigned to the Stumpffia hara species group on the basis of its molecular phylogenetic affinities. The new species is diagnosed by the unique combination of the following characters: (1) Small-sized species (SVL 14.2-16.6 mm); (2) manus with four fingers (first finger slightly reduced in length) and pes with five toes (first toe not reduced in length); (3) enlarged inner metacarpal tubercle; (4) terminal phalanges of fingers without enlarged discs, those of toes with very slightly enlarged discs; (5) relative hand length HAL/SVL 0.38; (6) relative foot length FOTL/SVL 0.62; (7) dorsum smooth; (8) supratympanic fold distinct; (9) colouration in life dorsally various shades of brown, ventrally with white and black flecks on a taupe to burnt orange background.

Stumpffia bishopi sp. nov. can be distinguished from S. analamaina , S. madagascariensis , S. larinki , S. yanniki , S. tridactyla , S. contumelia , S. obscoena , S. davidattenboroughi , S. betampona , S. dolchi , S. froschaueri , S. makira , S. pygmaea , and S. spandei by larger body size (> 14 mm vs < 14 mm); from S. miery , S. davidattenboroughi , S. tridactyla , S. contumelia , S. tetradactyla , S. makira , S. obscoena , S. betampona , S. dolchi , S. spandei , S. garraffoi , and S. yanniki by a lower degree of digital reduction with the first finger slightly reduced (vs greater reduction in first finger and toe; hands and feet were figured in Rakotoarison et al. 2017); from S. angeluci , S. maledicta , S. sorata , and S. miovaova by fourth finger slightly longer than second (vs fourth finger subequal in length to second); from S. psologlossa by the absence of dark blackish markings along the flank (vs presence), relatively larger hand length (HAL/SVL 0.38 vs 0.18-0.25), shorter call duration (127-153 ms vs 791-871 ms) and an unpulsed advertisement call (vs distinctly pulsed); from S. analanjirofo by smooth dorsum (vs moderately tubercular); from S. madagascariensis , S. davidattenboroughi , S. tridactyla , and S. contumelia by the lack of a sharp border between dorsal and lateral colour; from S. edmondsi , S. nigrorubra , and S. pardus by the lack of distinct colouration on the posterior shank; from S. iharana by presence of black spots on the venter (vs absence); from S. grandis by the lack of large white markings on the venter (vs present); from S. huwei by the lack of yellowish colouration in the venter (vs present); from S. madagascariensis , and S. angeluci by a shorter call duration (127-153 ms vs 179-198 ms); from S. larinki , by longer call interval (4388-6355 ms vs 2143-2289 ms), and by a higher frequency range of advertisement calls (3919-4091 Hz vs 2842-3057 Hz); from S. huwei , S. maledicta , S. kibomena , and S. mamitika by longer call duration (127-153 ms vs 70-124 ms); from S. fusca by relatively larger foot length (FOTL/SVL 0.62 vs 0.72-0.78); from S. kibomena , S. meikeae , S. miovaova , S. nigrorubra , and S. roseifemoralis by lack of red colour ventrally or on limbs (vs presence); from S. kibomena by unpulsed advertisement call (vs slightly pulsed).

Stumpffia bishopi sp. nov. may be distinguished from other members of the S. hara species group as follows: from S. hara , S. be , S. megsoni , and S. staffordi by substantially smaller SVL (14.2-16.6 vs 19.8-27.9 mm); additionally, from S. be , S. hara , and S. staffordi by less expanded terminal discs of fingers and toes; from S. megsoni and S. be by the absence of bright reddish or orange colouration the limbs and abdomen (vs presence; variable in S. megsoni , see below); from S. hara by the more pronounced supratympanic fold in life, and dark brown pigmentation on the chin (vs absence of pigmentation in examined specimens).

Description of the holotype.

Specimen in good state of preservation, left thigh muscle removed as a tissue sample. Body elongate; head slightly longer than wide, narrower than body; snout slightly pointed in dorsal view, pointed in lateral view; nostrils directed laterally, not protuberant, nearer to tip of snout than to eye; canthus rostralis slightly distinct, straight; loreal region concave, weakly oblique; tympanum distinct, about 52% of eye diameter; supratympanic fold not recognizable (was distinct in life; Fig. 2 View Figure 2 ); tongue long and narrow, broadening posteriorly, attached anteriorly, not notched; maxillary teeth and vomerine teeth absent; choanae rounded. Forelimb brachium (upper arm) slender, antebrachium (lower arm) robust; subarticular tubercles single, slightly distinct; outer metacarpal tubercle distinct, small; prepollical/inner metacarpal tubercle oval, producing a thickening of the inside of the first finger (Fig. 3 View Figure 3 ); fingers without webbing; relative length of fingers 1 < 2 < 4 < 3, fourth finger slightly longer than second, first finger slightly reduced in length; finger tips not expanded into discs. Hind limbs slender; TIBL 46% of SVL; lateral metatarsalia strongly connected; inner metatarsal tubercle small, oval; outer metatarsal tubercle absent; no webbing between toes; toe tips slightly expanded; relative length of toes 1 < 2 < 5 < 3 < 4; fifth toe shorter than third, no toe reduction; subarticular tubercles distinct, single. Skin on dorsum smooth, without distinct dorsolateral folds. Ventral skin smooth.

In life, the holotype was dark brown in base colour with honey brown markings on the flanks, dorsal and lateral head, and shanks, giving it an interesting wood-grain appearance (Fig. 2 View Figure 2 ). The mid-dorsum had a darker brown marking forming a subtriangular area between the back of the eyes and the dorsum that extended down to the postsacral area. There were distinct crossbands on the thighs and less distinct ones on the shanks. The ventral colour was mottled burnt orange posteriorly, flecked with numerous tiny white and black spots, especially white over the anterior abdomen; brown on the sternal area, and dark brown on the chin. After 3.5 years in preservative, the colouration has darkened considerably (Fig. 3 View Figure 3 ); the dorsum is almost uniformly dark brown with the lightest markings faded to a light grey. The venter is cream flecked with grey, more yellow in tone on the ventral legs. The ventral white flecks are no longer distinct, having merged with the base translucency of the skin.

Variation.

For morphometric variation, see Table 2 View Table 2 . The shape of the first finger differs among specimens, with ZSM 107/2018 having a pronounced first finger without medial swelling (i.e. no developed prepollex), and the other two individuals having a swollen prepollex and consequently short-looking first finger (Fig. 3 View Figure 3 ). In life, the tip of the urostyle protruded distinctly in the specimens we collected (Fig. 2 View Figure 2 ), but it is unclear whether or not this is a diagnostic feature. It diminished in preservative. The colouration of this species is quite variable (see Fig. 2 View Figure 2 ), ranging from the distinct patterning of the holotype to the rather uniform dorsal colouration of the paratype UADBA-A 60224. In all specimens, the inner half of the dorsal hand is consistently light in colour, and the chin is rather dark brown.

Etymology.

The species name is a patronym honouring the late Phil Bishop, Professor Emeritus at the University of Otago, who dedicated his life to research on and protection of amphibians. He was an inspirational and incredibly enthusiastic colleague, and we were sorry to lose him far too soon.

Distribution and conservation status.

Stumpffia bishopi sp. nov. is known only from the Montagne d’Ambre, northern Madagascar, at high elevations of ca 1330-1480 m above sea level (Fig. 4 View Figure 4 ). The conservation status of the species is in line with other endemics of Montagne d’Ambre: it is known from a single threat-defined location, the protected area of Montagne d’Ambre National Park. Although the extent of occurrence is small enough to qualify for the Critically Endangered category, there are only mild on-going declines to the extent or quality of the habitat, and no known fluctuations in population size or distribution. A change in the protected area’s status would jeopardise the survival of the species, however, so we conservatively recommend listing it as Near Threatened.

Natural history.

Almost nothing is known of the natural history of this species, except that it lives in the leaf litter of high-elevation rainforest on Montagne d’Ambre. The specimen ZSM 107/2018 (MSZC 0730) was calling from a semi-exposed and slightly elevated position bordering a path above Grand Lac (12.5995°S, 049.1592°E, ca 1330 m a.s.l.). The left thigh of UADBA 60224 had a small orange spot that is probably a trombiculid mite (Fig. 2 View Figure 2 ; Wohltmann et al. 2007).

Call.

Advertisement calls were recorded by S.M. Rasolonjatovo, on 3 December 2017, at 20:25 h, in high elevation rainforest near Grand Lac on Montagne d’Ambre National Park, from the specimen ZSM 107/2018 (MSZC 0730). The individual was sitting on leaf litter. The call consists of a single short tonal note repeated in series at regular intervals (Fig. 5 View Figure 5 ). Numerical parameters are as follows: call duration (= note duration) 127-153 ms (138 ± 9.3 ms; N = 6), inter-call intervals 4388-6355 ms (5362 ± 840.5 ms; N = 5), and a dominant frequency at 3919-4091 Hz (3983 ± 70.6 Hz, N = 6).

Kingdom

Animalia

Phylum

Chordata

Class

Amphibia

Order

Anura

Family

Microhylidae

Genus

Stumpffia