Platypelis laetus, Rakotoarison & Scherz & Köhler & Ratsoavina & Hawlitschek & Megson & Vences & Glaw, 2020

Rakotoarison, Andolalao, Scherz, Mark D., Koehler, Joern, Ratsoavina, Fanomezana M., Hawlitschek, Oliver, Megson, Steven, Vences, Miguel & Glaw, Frank, 2020, Frogs of the genus Platypelis from the Sorata massif in northern Madagascar: description of a new species and reports of range extensions, Zoosystematics and Evolution 96 (1), pp. 263-274 : 263

publication ID

https://dx.doi.org/10.3897/zse.96.47088

publication LSID

lsid:zoobank.org:pub:7F7AC988-1EF8-4014-8DDC-0BE0ABA09B4F

persistent identifier

https://treatment.plazi.org/id/80E35235-9E39-48EC-ACB0-525952C098BC

taxon LSID

lsid:zoobank.org:act:80E35235-9E39-48EC-ACB0-525952C098BC

treatment provided by

Zoosystematics and Evolution by Pensoft

scientific name

Platypelis laetus
status

sp. nov.

Platypelis laetus sp. nov.

Remark.

This species has been listed as Platypelis sp. CaNEW2 Sorata by Scherz et al. (2016, 2017) and Peloso et al. (2017).

Holotype.

Holotype ZSM 5652/2012 (FGZC 3761) (Figs 3a-c View Figure 3 , 4 View Figure 4 ), adult male, collected on 30 November 2012, in the Sorata Massif (near 13.6817S, 49.4411E, 1339 m a.s.l.), northern Madagascar, by F. Glaw, O. Hawlitschek, T. Rajoafiarison, A. Rakotoarison, F.M. Ratsoavina, and A. Razafimanantsoa.

Paratypes.

ZSM 5651/2012 (FGZC 3588) (Fig. 3d, e View Figure 3 ) collected on 26 November 2012 from the high elevation of the Sorata Massif (near 13.6745S, 49.4402E, 1541 m a.s.l.), northern Madagascar, by the same collectors as the holotype; ZSM 5653/2012 (FGZC 3762) (Fig. 3f, g View Figure 3 ), adult male, collected on 30 November 2012, from the same site and by the same collectors as the holotype; UADBA-A (FGZC 3767) and UADBA-A (FGZC 3768), both ovigerous adult females, collected on 30 November 2012 from the same site and by the same collectors as the holotype.

Diagnosis.

Assigned to the genus Platypelis in the microhylid subfamily Cophylinae based on enlarged terminal discs on fingers and toes, absence of nuptial pads, and molecular phylogenetic relationships. The species can be identified among other cophylines by the combination of the following character states: (1) medium-sized species (adult male SVL 24.3-25.6 mm); (2) manus with second finger slightly shorter than fourth and pes with third toe much shorter to very slightly shorter than fifth; (3) males with prepollical tubercle but lacking a finger-like prepollex as typical for Anodonthyla ; (4) throat greenish in life; (5) chest and anterior belly translucent gray, with distinct white spotting that is absent on the posterior belly; (5) absence of red color on limbs and ventral side.

Platypelis laetus sp. nov. can be distinguished from P. grandis and P. alticola by smaller body size (verified adult male SVL 24.3-25.6 mm vs 30-105 mm), and furthermore from P. grandis by a largely smooth dorsal skin (vs strongly granular and bumpy) and from P. tuberifera by dark pattern on the dorsum (vs uniformly beige-yellowish) and body not conspicuously flattened (vs flattened); from P. pollicaris by a slightly smaller body size (verified adult male SVL 24.3-25.6 mm vs 26-28 mm), third toe shorter than fifth (vs both toes of similar length) and less elongated body (vs conspicuously elongated); from P. tuberifera and P. cowanii by smaller body size (verified adult male SVL 24.3-25.6 mm vs 30-40 mm) and by third toe shorter than fifth (vs third toe longer than fifth); from P. tsaratananaensis by having a plump body (vs slender with a distinctively elongated “neck” region), absence of vomerine teeth (vs presence), and especially in call structure (see below); from P. tetra , P. barbouri , P. karenae , P. ravus , and P. ando by larger body size (SVL 24.3-25.6 mm vs 16-19 mm); from P. milloti by throat greenish colored (vs brownish) and by absence of red ventral color and of a very distinct dorsal pattern (vs presence); from P. barbouri and P. ranjomena by the absence of red color on ventral side or limbs (vs presence); from P. mavomavo by third toe shorter than fifth (vs third toe longer than fifth) and grayish with white spots on the chest (vs uniformly yellow on venter). Among the described species of Platypelis , the new species is phylogenetically closest to P. olgae . It differs from this species by larger body size (adult male SVL 24.3-25.6 mm vs 20.3-21.9 mm), and by third toe often shorter than fifth (vs third toe equal to or longer than fifth).

Bioacoustically, P. laetus sp. nov. can be distinguished from most congeners by its rather short note duration of only 73-88 ms. The following Platypelis species all emit longer notes: P. alticola (411-466 ms), P. ando (424-441 ms), P. barbouri (142-160 ms), P. karenae (131-145 ms), P. pollicaris (160-180 ms), P. ranjomena (303-379 ms), P. ravus (384-443 ms), and P. tuberifera (280 ms) ( Glaw and Vences 1994; Glaw et al. 2012, 2020; Rakotoarison et al. 2012; Rosa et al. 2014; Scherz et al. 2019). Calls of P. grandis are non-tonal, those of P. milloti are shorter in duration (55-65 ms) and the call of P. tsaratananaensis consist of two notes, rather than a single note ( Glaw and Vences 1994; Rakotoarison et al. 2012). Known calls of Cophyla species ( C. berara , C. fortuna , C. maharipeo , C. noromalalae , C. occultans , C. phyllodactyla , C. puellarum ) all exhibit a much longer note duration compared to the new species, ranging from 326 ms in the shortest to 1346 ms in the longest notes (see Rakotoarison et al. 2015, 2019b).

Description of the holotype.

Adult male in good state of preservation, some muscle tissue removed from right thigh; snout-vent length 25.6 mm (for further measurements see Table 1 View Table 1 ); body plump; head slightly wider than long, not wider than body; snout slightly rounded in dorsal view and blunt in lateral view; nostrils not protuberant, nearer to tip of snout than to eye; canthus rostralis distinct, straight; loreal region straight, slightly oblique; tympanum distinct, 60% of eye diameter; supratympanic fold distinct, starting at the posterior border of the eye and ending anterior to the forelimb; tongue long, broadening posteriorly, attached anteriorly, not notched; maxillary teeth present and vomerine teeth absent; choanae rounded. Forelimbs robust; subarticular tubercles single, indistinct; outer metacarpal tubercle small, rounded; prepollex/inner metacarpal tubercle distinct, forming a distinct protuberance at base of first finger; hand without webbing; fingers distinctly broadly rounded to slightly bilobate, with lateral fringes, smaller than discs of fingers; relative length of fingers 1<2<4<3; nuptial pads absent. Hindlimbs slender; tibiotarsal articulation reaching between forelimb and tympanum when hindlimb adpressed along body; tibia length 47% of SVL; inner metatarsal tubercle small, oval; outer metatarsal tubercle absent; webbing between toes weakly developed, with traces of webbing between third and fourth toe; subarticular tubercles on toes single; toes flattened and their discs relatively broad, broadly rounded to slightly bilobate; relative length of toes 1<2<3<5<4; third toe slightly shorter than fifth, dorsal skin smooth, without dorsolateral folds, ventral skin smooth on throat and chest and moderately granular on belly.

After nine years of preservation in 70% ethanol, the dorsum is light beige with a brown, teddy-bear-shaped patch flecked with cream from between the eyes to the inguinal region. The nostril is surrounded with brown. The lateral surface is homogenously light beige flecked with small brown dots. The flank coloration merges with the ventral coloration. The ventral trunk and the chin are light beige. The ventral thigh is beige spotted with brown in the cloacal region. The shank, tarsus and foot are ventrally beige. Dorsally, the thigh is beige with light brown crossbands. The posterodorsal surface of the thigh is beige spotted with light brown. The shank is beige with a brown crossband. The coloration of the distal portion of the shank merges with the coloration of the tarsus, extending to the toes. The arms are beige with a brown crossband. The coloration in life is shown in Fig. 3 View Figure 3 (in dorsal, lateral and ventral view).

Variation.

For variation in measurements, see Table 1 View Table 1 . In general, the two examined adult paratypes agree well with the holotype, but with the following differences: The holotype and FGZC 3588 have plump bodies and FGZC 3762 is rather slim. Relative toe length is variable: the third toe is distinctly shorter than fifth on one foot, and slightly shorter on the other foot in FGZC 3588, slightly shorter in the holotype FGZC 3761, and very slightly shorter to equal in FGZC 3762. Overall, specimens in life have a dorsal surface with some irregular granules. In coloration, FGZC 3762 is the darkest specimen of the type series in preservative and FGZC 3588 is the lightest. The teddy-bear pattern of the dorsum of the holotype and FGZC 3588 is absent in FGZC 3762.

Distribution.

The species is known only from the Sorata Massif, northern Madagascar, at elevations of 1339-1541 m above sea level (Fig. 2 View Figure 2 ).

Natural history.

Platypelis laetus sp. nov. occurs in rainforest on the Sorata Massif, but most of the specimens were collected in the bamboo forest of the massif. The holotype was calling from a bamboo hole at about 5 m above the ground. The bamboo node was occupied by another specimen, was water-filled, and contained 35 whitish eggs and embryos, probably of this species, in at least two different developmental stages (Fig. 3h View Figure 3 ). Another male was found on a palm tree at around 4 m above the ground. Calling occurred around dusk.

Etymology.

The specific epithet is a masculine Latin adjective meaning “happy”. The new species is so named in reflection of the joy and happiness of the first author to get to work on the cophyline microhylid frogs of Madagascar.

Vocalization.

The advertisement call of Platypelis laetus sp. nov. consists of a single short tonal note (Fig. 5 View Figure 5 ) repeated at regular intervals in long call series. Analysis of 43 calls belonging to three different males recorded on 30 November 2012 in Sorata revealed the following numerical parameters (ca. 15 °C air temperature): note duration (= call duration) 73-88 ms (83.4 ± 4.3 ms), inter-note interval 1465-2378 ms (1940 ± 255 ms), and dominant frequency 4707-4793 Hz (4742 ± 38 Hz). Each note exhibits some regular upward frequency modulation starting at around 4600-4700 Hz and terminating at 4770-4900 Hz. This narrow frequency band also constitutes the prevalent bandwidth of the call, although two additional rather weak frequency bands are present at around 2400 Hz and 7200 Hz. There is also a slight degree of amplitude modulation recognizable within notes, but the pattern of these modulations seems to be rather variable among notes (and possibly may constitute an artifact because of some recording device damage; see Materials and methods).

Range extensions of other Platypelis species

Kingdom

Animalia

Order

Anura

Family

Microhylidae

Genus

Platypelis