Platypelis

Rakotoarison, Andolalao, Glaw, Frank, Vieites, David R., Raminosoa, Noromalala R. & Vences, Miguel, 2012, Taxonomy and natural history of arboreal microhylid frogs (Platypelis) from the Tsaratanana Massif in northern Madagascar, with description of a new species, Zootaxa 3563, pp. 1-25 : 4-5

Diversity of Platypelis in the Tsaratanana Massif

In the 2010 expedition, Platypelis specimens were found in large quantities in bamboo forest, but partly also outside of it, along the Maromokotro trail. Our specimens along this trail morphologically clustered neatly into three species ( Figs. 3–6 ): (1) a large and rather stout species reaching 45 mm SVL that called at night from bamboo forest and emitted stereotyped series of single-note calls; (2) a very common smaller species with smooth skin and typically less than 30 mm SVL with an elongated body, that at night emitted series of unique double-note calls not known from any other Platypelis ; and (3) a small-sized species with yellowish or greenish color on the venter, found only rarely and at higher elevations, of which no calls were heard. Based on the re-examination of historical type specimens as reported in the Identity sections of the respective species below, we assign the first and second of these species to Platypelis alticola and P. tsaratananaensis , respectively, and the third to a new species described below as Platypelis olgae sp. nov.

None of the specimens collected in the 2001 expedition could be reliably assigned to nominal species (Andreone et al. 2009). Because in that period, tissue samples were not collected from all encountered specimens, a detailed screening of molecular diversity is not possible for the Platypelis from the western slope. A photographed specimen from Antsahamanara campsite (in the Manarikoba forest), however, had a unique coloration and a DNA sequence could be assigned to this specimen, which we here name Platypelis sp. 8 following the numbering of candidate species first applied by Vieites et al. (2009). This species was not found on the Maromokotro trail or at other sites in 2010.

The phylogenetic tree obtained on the basis of DNA sequences of the 16S rRNA gene ( Fig. 7 ) provides evidence for the presence of four genetic lineages occurring on the Tsaratanana Massif, corresponding to the species respectively candidate species mentioned above: P. alticola , P. tsaratananaensis , P. olgae sp. nov. and P. sp. 8. These four lineages were placed together in a clade which however did not receive significant (PP>0.95) support from Bayesian posterior probabilities. In P. alticola , two sublineages were identified corresponding to the low vs. high-elevation populations, whereas the other three lineages were genetically homogeneous.

Figures

FIGURE 3. Photographs in life of Platypelis alticola and P. sp. 8. (a, b) Two specimens of P. alticola from Antevialambazaha (Tsaratanana, Maromokotro trail, camp 1); (c, d) two specimens of P. alticola in Matsabory Maiky (Maromokotro trail, camp 2), (d) shows the adult male ZSM 1657 / 2010 (ZCMV 12453); (e) specimen of P. alticola from Bepia campsite (Tsaratanana, Maromokotro trail, camp 3); (f) Platypelis sp. 8 from Antsahamanara (Manarikoba forest, western slope of Tsaratanana).

FIGURE 4. Variation of color in life of Platypelis tsaratananaensis from the Tsaratanana region: (a) ZSM 1644 / 2010 (ZCMV 12607) from Matsabory Maiky campsite; (b) ZSM 1648 / 2010 (ZCMV 12361) from Matsabory Maiky; (c) UADBA uncatalogued from Antevialambazaha campsite; (d) ZSM 1649 / 2010 (ZCMV 12391) from Matsabory Maiky; (e) ZSM 1645 / 2010 (ZCMV 12610) from Matsabory Maiky; (f) UADBA uncatalogued from Antevialambazaha campsite.

FIGURE 5. Specimens of Platypelis olgae sp. nov. in life. (a) Male holotype, ZSM 1666 / 2010 [ZCMV 12402]) from near Andranomadio (Maromokotro trail camp 4); (b) female paratype ZSM 1667 / 2010 (ZCMV 12428) and (c) male paratype ZSM 1668 / 2010 (DRV 6225) from Amboditsaratanana (Maromokotro trail camp 5).

FIGURE 6. Ventral sides of the four species of Platypelis found in the Tsaratanana Massif, photographed from specimens in life. Inset photos show the same specimens in dorsolateral view. (a) P. alticola, Matsabory Maiky, female; (b) P. alticola, Antevialambazaha, probable male; (c) P. tsaratananaensis, female, Matsabory Maiky (ZSM 1648 / 2010 [ZCMV 12361]); (d) P. tsaratananaensis, male, Matsabory Maiky; (e) P. olgae sp. nov. (female paratype, ZSM 1667 / 2010 [ZCMV 12428]), Amboditsaratanana; (f) P. olgae sp. nov. (male holotype, ZSM 1666 / 2010 [ZCMV 12402]), near Andranomadio; (g) P. sp. 8, Antsahamanara.

FIGURE 7. 50 % majority-rule consensus tree from a Bayesian analysis of partial DNA sequences of the 16 S rRNA gene of Platypelis. Values on nodes are posterior probabilities (not shown if <0.95). Cophyla berara was used as the outgroup (not shown).