Guibemantis razandry, Koppetsch & Pabijan & Hutter & Köhler & Gehring & Rakotoarison & Ratsoavina & Scherz & Vieites & Glaw & Vences, 2023

Koppetsch, Thore, Pabijan, Maciej, Hutter, Carl R., Koehler, Joern, Gehring, Philip-Sebastian, Rakotoarison, Andolalao, Ratsoavina, Fanomezana M., Scherz, Mark D., Vieites, David R., Glaw, Frank & Vences, Miguel, 2023, An initial molecular resolution of the mantellid frogs of the Guibemantis liber complex reveals three new species from northern Madagascar, Vertebrate Zoology 73, pp. 397-432 : 397

Guibemantis razandry sp. nov.

Figs 9 , 11

Holotype.

ZSM 293/2005 (field number FGZC 2851), adult male, collected in Marojejy National Park (14.43767°S, 49.77555°E, 1326 m a.s.l.), Sava Region, northeastern Madagascar on 26 February 2005 by F. Glaw, M. Vences and R.D. Randrianiaina.

Paratypes.

A total of 26 specimens: ZSM 294-295/2005 (field numbers FGZC 2865, FGZC 2867), two adult males, same collection data as holotype; ZSM 424/2016 (field number ZCMV 15176), adult male, collected at Marojejy, near Camp 3 “Simpona” (14.43661°S, 49.74335°E, 1325 m a.s.l.) on 17 November 2016 by M.D. Scherz, A. Rakotoarison, M.C. Bletz, M. Vences and J. Razafindraibe; ZSM 513/2009 (ZCMV 11218), adult male, collected near Hevirina, western slope of Makira Reserve (ca. 15.4490°S, 49.1119°E, 1093 m a.s.l.), on 23 June 2009 by M. Vences, D.R. Vieites, F. Ratsoavina, R.D. Randrianiaina, E. Rajeriarison, T. Rajofiarison, and J. Patton; ZSM 1682-1689/2010 (field numbers ZCMV 12569-12584), adults and subadults, collected near Bemanevika river (14.48251°S, 48.62723°E, 1109 m a.s.l.) on 29 June 2010 by M. Vences, D. Vieites, R.D. Randrianiaina, F. Ratsoavina, S. Rasamison, A. Rakotoarison, E. Rajeriarison and T. Rajoafiarison; ZSM 1738-1743/2010 (field numbers ZCMV 12377, 12441, 12462, 12463, 12466, 12468), adults and subadults collected at Camp 2 (Matsaborimaika) on the Tsaratanana Massif (14.15256°S, 48.95728°E, 2021 m a.s.l.) on 15-20 June 2010 by M. Vences, D. Vieites, R.D. Randrianiaina, F. Ratsoavina, S. Rasamison, A. Rakotoarison, E. Rajeriarison and T. Rajoafiarison; ZSM 1894-1900/2009 (ZCMV 11352-11365), from the western slope of Makira Reserve (probably from Ampofoko campsite), collected in June/July 2009 by M. Vences, D.R. Vieites, J. Patton, R.D. Randrianiaina, F. Ratsoavina and E. Rajeriarison; KU 347374 (CRH1693), specimen of unknown sex and maturity, collected at Anjanaharibe-Sud Special Reserve (14.698°S, 49.465°E) by C.R. Hutter and Z.F. Andriampenomanana.

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 Guibemantis 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.

Description of holotype.

Adult male in excellent state of preservation (Fig. 9 ). A small piece of muscle tissue from right thigh removed for molecular analysis. SVL 25.6 mm. For full morphometric measurements see Table 1 . Body relatively slender; head slightly longer than wide, wider than body; snout rounded in dorsal, ventral, and lateral views; nostrils much nearer to tip of snout than to eye and pointed anterolaterally; canthus rostralis distinct, slightly concave; loreal region concave; tympanum distinct, relatively small, its diameter 69% of eye diameter; distinct supratympanic fold; tongue ovoid, distinctly bifid posteriorly; vomerine teeth as one weakly expressed rounded aggregation posterolateral of each choana; choanae small, rounded. Forelimbs slender; subarticular tubercles distinct and single; central metacarpal tubercle large and rounded, outer metacarpal tubercle smaller and oval; a small but indistinct prepollex (which could also be considered as an inner metacarpal tubercle) at base of first finger. Fingers without webbing; relative finger length I<II<IV<III; finger discs distinctly enlarged; nuptial pads absent. Outer toe and finger discs darker than inner toe and finger discs. Hind limbs long and slender; when adpressed along body, tibiotarsal articulation reaches beyond eye; lateral metatarsalia connected by tissue; inner metatarsal tubercle distinct, larger than outer; outer metatarsal tubercle distinct; webbing formula of foot 1(traces), 2i(traces), 2e(1), 3i(2.5), 3e(1.5), 4i(2.75), 4e(3), 5(1); relative toe length I<II<III = V<IV. Skin dorsally smooth; ventral skin smooth on throat and chest, slightly granular on belly. Femoral glands relatively distinct from external view, consisting of large number of small gland granules in a relatively diffuse field covering most of thigh ventrally, thus of type 1 as defined by Glaw et al. (2000). In life gland granules distinctly recognizable as small greenish-yellowish units, at least 170 in one gland (Fig. 11 ).

After sixteen years in preservative (70% EtOH; Fig. 9 ), dorsal background coloration light brownish with two prominent dark brownish dorsolateral bands extending posteriorly from eye orbits to hips. Rostral stripe dark brownish. Dorsally numerous dark reddish brown irregular spots present, particularly between orbits and at middorsum. Forelimbs have irregular and partially interrupted dark, brownish bands and spots extending from shoulders to fingers. Outer finger discs reddishbrown. Dorsal surface of thigh with broad dark blotches and interrupted bands. These darkish patterns extend to shanks and continue as single blotches and spots on feet and toes. Like finger discs, some outer toe discs dark reddish brown, noticeably different than adjacent tissue.

Based on photographs of holotype in life (Fig. 11 ), body coloration was as follows: on dorsum reddish brown, on limbs and laterally greenish gray. Dorsolaterally a thin yellowish line on each side. Irregular-sized dark blackish brown spots and dots middorsally and laterally, but particularly on both fore- and hindlimbs. Supratympanic fold and rostral stripe blackish brown. Paired, thin white dorsal lines in life (not visible in preservative) (Fig. 11 ). Background color of ventral surface whitish to greenish, chest and throat bright white. Posterior and lateral parts of abdomen semi-transparent. Femoral gland granules yellow. Iris (whitish in preservative) apparently glossy golden in life.

Variation.

Specimens of G. razandry show a high variation in color pattern, but overall appear to have a lighter color compared to the sympatric G. razoky sp. nov. (described below; compare Fig. 11 vs. Fig. 12 ). In general, the ground color of G. razandry sp. nov. is light brown to beige, with different darker brown patterns. ZSM 513/2009 has a light brown ground color, darker flanks, and a broad light beige vertebral stripe. ZSM 424/2016 has an extremely contrasted pattern, with a light beige dorsal side, bordered by dark brown color that occupies most of the flanks. Breeding males (such as ZSM 424/2016) have bright white vocal sacs, but these are not visible in other individuals collected out of the breeding season and some of these could in fact not be sexed with full reliability (as part of the inner organs have been damaged during dissection for amphibian parasites). For variation in morphometric features see Table 1 .

Natural history.

Males of G. razandry have been observed at night, calling from perches in the vegetation about 1-2 m above the ground, typically at the edge of swamps in primary rainforest. On the Marojejy Massif, they sometimes call sitting on leaves in the vegetation near dry beds of temporary headwater streams. At the same site, we also found a clutch with quite well-developed larvae on a leaf that may belong to this species. We also found clutches that were faded and whitish, which may have been infected with a fungus or bacterial growth. Outside of the breeding season (in June) we found specimens near Bemanevika River hidden in the leaf axils of Pandanus screw pines, syntopic with Blommersia blommersae , Guibemantis sp. aff. pulcher , and G. razoky sp. nov. The species occurs both in areas of primary rainforest, and in highly degraded and fragmented forest patches, e.g., near Bemanevika.

Vocalization.

Advertisement calls recorded on 16 February 2005 at Marojejy National Park (air temperature unknown) consist of a single pulsatile note of somewhat variable duration. Calls (= notes) are usually emitted in short series at rather regular intervals (Fig. 17 ). No clear pulse structure is evident within notes, with pulses being largely fused. Slight amplitude modulation is evident in calls with maximum energy being present in the first third of the call’s duration. Numerical parameters of 14 analyzed calls are as follows: call duration (= note duration) 74-134 ms (98.3 ± 18.3 ms); dominant frequency 3854-4207 Hz (4069 ± 129 Hz); prevalent bandwidth 2000-5200 Hz. Within call series (containing 7-8 calls; maximum duration of call series 2172 ms), call rate varied from 163-255 calls/minute.

Distribution.

The species is known from various sites in northern Madagascar, all at mid- to high-elevation: (1) the type locality Marojejy (Camp Simpona, at mid-elevation), (2) Bemanevika, (3) the southern slope of the Tsaratanana Massif, (4) the western slope of Makira Reserve, and (5) Anjanaharibe-Sud Reserve, based on specimen CRH1693 (KU 347374) included in the FrogCap analysis (Fig. 8 ). At Makira (west), Bemanevika and Tsaratanana, the species occurs syntopically with G. razoky sp. nov. (described below). The species is known from elevations between 1093 and 2021 m a.s.l.

Etymology.

The name is derived from the Malagasy word Guibemantis 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.

Figures

Figure 8. Maximum likelihood tree based on a partitioned analysis of 12,951 nuclear-encoded markers obtained via the FrogCap strategy for representative samples of the main lineages of the G. liber complex, calculated with IQ-Tree. Numbers at nodes are bootstrap values in percent.

Figure 9. Preserved name-bearing holotype specimens of Guibemantis razandry sp. nov. (ZSM 293 / 2005) (A, B), Guibemantis razoky sp. nov. (ZSM 1746 / 2010) (C, D), and Guibemantis fotsitenda sp. nov. (ZSM 292 / 2005) (E, F) in dorsal and ventral view.

Figure 11. 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).

Figure 12. 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), and 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).

Figure 17. Audiospectrogram and corresponding oscillogram of a series of advertisement calls (3 calls) of Guibemantis razandry sp. nov. recorded on 16 February 2005 at Marojejy National Park. Recording band-pass filtered at 1000 - 9500 Hz.