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[A-B, E-F] Guibemantis razandry [A-H] Guibemantis razoky Koppetsch, Pabijan, Hutter, Köhler, Gehring, Rakotoarison, Ratsoavina, Scherz, Vieites, Glaw & Vences, 2023 DOI: 10.3897/vz.73.e94063 |
Abstract
The small arboreal frog Guibemantis liber (Anura: Mantellidae) has served as an example for the existence of deep conspecific lineages that differ by a substantial amount in mitochondrial DNA but are similar in morphology and bioacoustics and thus are assigned to the same nominal species. During fieldwork in northern Madagascar, we identified additional such lineages and surprisingly, observed close syntopy of two of these at various sites. In-depth study based on DNA sequences of the mitochondrial cytochrome b gene from 338 specimens of G. liber sensu lato from across its range, sequences of four nuclear-encoded markers for 154‒257 of these specimens, a phylogenomic dataset obtained by the FrogCap target capture approach, and additional mitochondrial genes for representatives of most mitochondrial lineages, as well as bioacoustic and morphological comparisons, revealed concordant differentiation among several lineages of the G. liber complex. We identify nine lineages differing by 5.3‒15.5% in cytochrome b and 2.4‒10.1% in the 16S rRNA gene, and find that several of these lack or have only limited allele sharing in the nuclear-encoded genes. Based on sympatric or parapatric occurrence without genetic admixture, combined with differences in bioacoustic and morphological characters, we scientifically name three lineages from northern Madagascar as new species: G. razoky sp. nov., G. razandry sp. nov., and G. fotsitenda sp. nov. Of these new species, G. razoky sp. nov. and G. razandry sp. nov. show widespread syntopy across northern Madagascar and differ in body size and advertisement calls. Guibemantis fotsitenda sp. nov. is sister to G. razandry sp. nov., but appears to occur at lower elevations, including in close geographic proximity on the Marojejy Massif. We also detected subtle differences in advertisement calls among various other mitochondrial lineages distributed in the Northern Central East and Southern Central East of Madagascar, but the status and nomenclatural identity of these lineages require further morphological and bioacoustic study of reliably genotyped individuals, and assignment of the three available names in the complex: Rhacophorus liber Peracca, 1893, Gephyromantis albogularis Guibé, 1947, and Gephyromantis variabilis Millot and Guibé, 1951. We discuss the identity and type material of these three nomina, designate a lectotype for Gephyromantis variabilis from Itremo, and flag the collection of new material from their type localities, Andrangoloaka and Itremo, as paramount for a comprehensive revision of the G. liber complex.
Keywords: Amphibia, Anura, bioacoustics, FrogCap, morphology, Pandanusicola, phylogeography, taxonomy
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| Specimens of Guibemantis razandry sp. nov. in life, in dorsal and ventral views. A, B Male holotype ZSM 293/2005 (field number FGZC 2851) from Marojejy. C, D Male specimen from Marojejy, photographed in 2016 (not collected). E, F Specimen from Bemanevika, probably a (maybe subadult) female, assigned to the species by color pattern only, photographed in 2010 (not collected). |
Guibemantis razandry sp. nov.
Diagnosis: This species corresponds to the mitochondrial lineage NE1 as defined herein, and to the candidate species Guibemantis sp. Ca21 according to Perl et al. (2014). It is assigned to the subgenus Pandanusicola of the genus Guibemantis based on presence of intercalary elements between ultimate and penultimate phalanges of fingers and toes (verified by external examination), small body size, moderate to weakly expressed webbing between toes, connected lateral metatarsalia, the presence of both inner and outer metatarsal tubercles, femoral glands in males, absence of nuptial pads, small body size (SVL 24.4‒25.9 mm in reliably sexed males and 22.8 mm in one female), and molecular phylogenetic relationships. Within Pandanusicola, the new species is distinguished from all species except G. liber and G. tasifotsy by femoral glands type 1 (vs. type 2) as defined by Glaw et al. (2000), thus possessing many small gland granules in a relatively diffuse field covering most of the thigh ventrally, and by its probable breeding in open swamps (vs. phytotelmic breeding in Pandanus leaf axils). It can be distinguished from G. tasifotsy by its different brownish color pattern lacking a green dorsal and lateral coloration with a series of distinct white blotches along the lower flanks and its strongly different advertisement call, consisting of a pulsatile note with numerous pulses being largely fused (vs. a trill-like note containing 3–7 distinctly separated pulses). The new species differs from all G. liber lineages occurring in the Northern and Southern Central East of Madagascar by its high DNA divergence, with > 5% uncorrected pairwise distance in the mitochondrial 16S gene and 20 diagnostic positions in the analyzed fragment of the cytochrome b gene (see Appendix 2 for a list of diagnostic sites), as well as probably by a somewhat smaller snout-vent length. For a distinction from the other two new species described herein, see below.
Etymology: The name is derived from the Malagasy word razandry meaning smaller (younger) sibling, and makes reference to the fact that this species is the smaller-sized relative of the syntopic larger-sized species of the G. liber complex described in the following. The name is used as a noun in apposition to the genus name.
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| Specimens of Guibemantis razoky sp. nov. in life, in dorsal and ventral views. A, B Male holotype ZSM 1746/2010 (field number ZCMV 12515) from Bemanevika. C, D Female paratypes ZSM 1744/2010 (field number ZCMV 12513), E, F ZSM 1745/2010 (field number ZCMV 12514) from Bemanevika. G, H Male paratype from Montagne d’Ambre (ZSM 878/2003) (shown in Lehtinen et al. 2012 as G. liber). |
Guibemantis razoky sp. nov.
Diagnosis: This species corresponds to the mitochondrial lineages NOR+NCENTR as defined herein. It is assigned to the subgenus Pandanusicola of the genus Guibemantis based on presence of intercalary elements between ultimate and penultimate phalanges of fingers and toes (verified by external examination), moderate to weakly expressed webbing between toes, connected lateral metatarsalia, the presence of both inner and outer metatarsal tubercles, femoral glands in males, absence of nuptial pads, moderately small body size (SVL 26.5‒33.9 mm in males and 29.8‒32.8 mm in females), and molecular phylogenetic relationships. Within Pandanusicola, the new species is distinguished from all species except G. liber, G. razandry, and G. tasifotsy by femoral glands type 1 (vs. type 2) as defined by Glaw et al. (2000), thus possessing many small gland granules in a relatively diffuse field covering most of the thigh ventrally, and by its probable breeding in open swamps (vs. phytotelmic breeding in Pandanus leaf axils). It can be distinguished from G. tasifotsy by its different brownish color pattern lacking a green dorsal and lateral coloration with series of distinct white blotches along the lower flanks, and its different advertisement call, namely a short click-like note of 20–117 ms duration and 2598–3010 Hz dominant frequency (vs. a longer trill-like note of 147–516 ms duration and higher dominant frequency; Lehtinen et al. 2012). The new species differs from all G. liber lineages occurring in the Northern and Southern Central East of Madagascar by its high DNA divergence > 2.4% in the mitochondrial 16S gene, by a larger SVL, and differences in the advertisement call. It differs from G. razandry (described above) by larger SVL, different advertisement call, and a molecular 16S divergence >5.5%. It also differs from G. liber and G. razandry by 3 and 41 diagnostic positions in the analyzed fragment of the cytochrome b gene, respectively (see Appendix 2 for a list of diagnostic sites). For a distinction from the third new species described herein, see below.
Etymology: The name is derived from the Malagasy word razoky meaning larger (elder) sibling, and refers to the fact that this species is the larger-sized relative of the syntopic G. razandry. The name is used as a noun in apposition to the genus name.
Guibemantis fotsitenda sp. nov.
Diagnosis: This species corresponds to the mitochondrial lineage NE2 as defined herein. It is assigned to the subgenus Pandanusicola of the genus Guibemantis based on presence of intercalary elements between ultimate and penultimate phalanges of fingers and toes (verified by external examination), small body size, moderate to weakly expressed webbing between toes, connected lateral metatarsalia, the presence of both inner and outer metatarsal tubercles, femoral glands in males, absence of nuptial pads, small body size (SVL 25.1‒26.0 mm in males; female size unknown), and molecular phylogenetic relationships. Within Pandanusicola, the new species is distinguished from all species except G. liber, G. razandry, G. razoky, and G. tasifotsy by femoral glands type 1 (vs. type 2) as defined by Glaw et al. (2000), thus possessing a large number of small gland granules in a relatively diffuse field covering most of the thigh ventrally, and by its probable breeding in open swamps (vs. phytotelmic breeding in Pandanus leaf axils). It can be distinguished from G. tasifotsy by its different brownish color pattern lacking a green dorsal and lateral coloration with series of distinct white blotches along the lower flanks. The new species differs from all G. liber lineages occurring in the Northern Central East and Southern Central East of Madagascar by its high DNA divergence > 5% in the mitochondrial 16S gene, and probably by a somewhat smaller snoutvent length. Guibemantis razoky (see above) has a larger body size (26.5–33.9 mm in males, vs 25.1–26.0 mm in males of G. fotsitenda). Guibemantis razandry (see above) is the closest relative of G. fotsitenda sp. nov., and no obvious morphological differences between these two species are known, despite their clear divergence in mitochondrial and nuclear-encoded DNA in near-sympatry. The new species differs from G. liber, G. razandry, and G. razoky by 23, 23, and 50 diagnostic positions in the analyzed fragment of the cytochrome b gene, respectively (see Appendix 2 for a list of diagnostic sites).
Etymology: The name is derived from the Malagasy words fotsy meaning white, and tenda meaning throat, referring to the white throat (vocal sac) typical for this and other species of the G. liber complex. The name is used as a noun in apposition to the genus name.
Thore Koppetsch, Maciej Pabijan, Carl R. Hutter, Jörn Köhler, Philip-Sebastian Gehring, Andolalao Rakotoarison, Fanomezana M. Ratsoavina, Mark D. Scherz, David R. Vieites, Frank Glaw and Miguel Vences. 2023. An Initial Molecular Resolution of the mantellid Frogs of the Guibemantis liber complex reveals Three New Species from northern Madagascar. Vertebrate Zoology. 73: 397-432. DOI: 10.3897/vz.73.e94063
