Madagascan Species Research Articles

Taxonomizing a truly morphologically cryptic complex of dwarf geckos from Madagascar: molecular evidence for new species-level lineages within the Lygodactylus tolampyae complex.

The Lygodactylus tolampyae complex includes several deep genetic lineages of small diurnal geckos from the West and North West of Madagascar whose taxonomy is largely unsolved. We sequenced DNA fragments of one mitochondrial and four nuclear-encoded genes for up to 70 samples across the entire known range of these geckos. We find as many as 11 mitochondrial lineages differentiated by >4% pairwise distances in the 16S rRNA gene fragment, with >9% pairwise distance for the majority of lineage comparisons. Many of these lineages were concordantly differentiated in all of the nuclear-encoded genes without any haplotype sharing, despite the syntopic occurrence of some of them. We therefore hypothesize that the complex contains seven candidate species, but a comprehensive taxonomic resolution is complicated by various hindrances. These include incomplete sampling, with two lineages each known only from a single specimen, and one further lineage with no voucher specimens available for examination. Further hurdles are the probably lost holotype of L. tolampyae and its imprecise type locality, as well as the apparent lack of any morphological differentiation between the majority of the genetic lineages. Based on a survey of historical literature and the travel routes of the original collector, A. Grandidier, we conclude that the provenance of the holotype of L. tolampyae is likely in the wider Morondava area in the West and assign the sole candidate species from this area to this name. We then proceed to describe three species that represent separate genetic lineages for all markers studied: Lygodactylus morii sp. nov., a species common in Ankarafantsika National Park and several nearby sites in the North West; L. herilalai sp. nov., a species occurring in close syntopy with L. morii in Ankarafantsika without any signal of genetic admixture; and L. schwitzeri sp. nov. from Sahamalaza Peninsula in the North West. This leaves three more lineages without a name and with the need to gather additional samples, two from Namoroka National Park and one from other sites in the North West. We confirm the L. tolampyae complex to be an apparently rare example of truly cryptic reptile species in Madagascar, where even detailed morphological examination does not reveal morphological differences among lineages that are clearly evolutionarily independent and require recognition as distinct species due to their co-occurrence without admixture.

Will Dalbergia species survive climate change? Predicting the potential future distribution of threatened species in Madagascar

Many species of Dalbergia, the source of highly prized rosewood, are threatened with extinction, a situation compounded by climate change. Accurate estimates of how suitable habitat will be impacted by global change are needed to inform their sustainable management. We selected five commercially exploited species endemic to humid eastern Madagascar (D. baronii, D. louvelii, D. maritima, D. normandii, and D. orientalis) to explore the potential value of species distribution modeling for understanding factors influencing their current distributions and estimating future patterns of suitable habitat, using MaxEnt and locality information for 715 taxonomically and spatially validated occurrences. Eight bioclimatic variables were used for modeling; projections were made under three scenarios for climate change and two for CO2 emissions. The distribution of each of the five species is primarily influenced by precipitation seasonality. Their potential geographical range is predicted to decrease by 2100 (-5% to -33%) under the optimistic CO2 scenario (RCP 2.6) except for a slight expansion of D. normandii (+2%), and by -14% to -58% under the pessimistic scenario (RCP 8.5). Our results show that suitable habitat will likely decrease with climate change, even within protected areas. They provide valuable information for future application of IUCN Red List criterion A to exploited species with fragmented distributions, targeting ex-situ conservation and management, and guiding restoration, reforestation, and other actions to establish and reinforce Dalbergia populations in areas where they are more likely to persist during climate change over the present century and beyond.

Four new deciduous species of Hyperacanthus (Rubiaceae: Gardenieae) from western Madagascar: the sofikomba alliance

SummaryThe genus Hyperacanthus comprises 11 species, nine in Madagascar and two in Africa, although many Madagascan species remain undescribed. All Madagascan species of Hyperacanthus are evergreen trees occurring in humid and semi-humid forest. Four deciduous species occur in the dry forests of northern, western, and southern Madagascar but are unknown to science. These four species, collectively and informally referred to as the sofikomba alliance, are described here: H. decaryi, H. piliformis, H. septentrionale and H. sofikomba. Three of the four species are illustrated and all four are mapped. A key to species, species descriptions, other key taxonomic information, and preliminary conservation assessments are also provided.

Patterns of Grewia (Malvaceae) diversity across geographical scales in Africa and Madagascar.

Quantifying spatial species richness is useful to describe biodiversity patterns across broad geographical areas, especially in large, poorly known plant groups. We explore patterns and predictors of species richness across Africa in one such group, the palaeotropical genus Grewia L. (Malvaceae). Grewia species richness was quantified by extracting herbarium records from GBIF and Tropicos and creating geographical grids at varying spatial scales. We assessed predictors of species richness using spatial regression models with 30 environmental variables. We explored species co-occurrence in Madagascar at finer resolutions using Schoener's index and compared species range sizes and International Union for Conservation of Nature status among ecoregions. Lastly, we derived a trait matrix for a subset of species found in Madagascar to characterize morphological diversity across space. Grewia species occur in 50 countries in Africa, with the highest number of species in Madagascar (93, with 80 species endemic). Species richness is highest in Madagascar, with ≤23 Grewia species in a grid cell, followed by coastal Tanzania/Kenya (≤13 species) and northern South Africa and central Angola (11 species each). Across Africa, higher species richness was predicted by variables related to aridity. In Madagascar, a greater range in environmental variables best predicted species richness, consistent with geographical grid cells of highest species richness occurring near biome/ecoregion transitions. In Madagascar, we also observe increasing dissimilarity in species composition with increasing geographical distance. The spatial patterns and underlying environmental predictors that we uncover in Grewia represent an important step in our understanding of plant distribution and diversity patterns across Africa. Madagascar boasts nearly twice the Grewia species richness of the second most species-rich country in Africa, which might be explained by complex topography and environmental conditions across small spatial scales.

Population dynamics of plague vector fleas in an endemic focus: implications for plague surveillance.

Plague is a zoonotic vector-borne disease caused by the bacterium Yersinia pestis. In Madagascar, it persists in identified foci, where it is a threat to public health generally from September to April. A more complete understanding of how the disease persists could guide control strategies. Fleas are the main vector for transmission between small mammal hosts and humans, and fleas likely play a role in the maintenance of plague. This study characterized the dynamics of flea populations in plague foci alongside the occurrence of human cases. From 2018 to 2020, small mammals were trapped at sites in the central Highlands of Madagascar. A total of 2,762 small mammals were captured and 5,295 fleas were collected. The analysis examines 2 plague vector species in Madagascar (Synopsyllus fonquerniei and Xenopsylla cheopis). Generalized linear models were used to relate flea abundance to abiotic factors, with adjustments for trap location and flea species. We observed significant effects of abiotic factors on the abundance, intensity, and infestation rate by the outdoor-associated flea species, S. fonquerniei, but weak seasonality for the indoor-associated flea species, X. cheopis. A difference in the timing of peak abundance was observed between the 2 flea species during and outside the plague season. While the present study did not identify a clear link between flea population dynamics and plague maintenance, as only one collected X. cheopis was infected, the results presented herein can be used by local health authorities to improve monitoring and control strategies of plague vector fleas in Madagascar.

Wild edible yams from Madagascar: New insights into nutritional composition support their use for food security and conservation.

Yams (Dioscorea species) are an important food resource in Madagascar, where both cultivated winged yam (D. alata) and wild edible yams are consumed. However, there is limited knowledge on the nutrient composition of wild edible yams in Madagascar, and on how they compare with the cultivated winged yam. Therefore, in this study, nine wild edible yam species, one with two subspecies from Madagascar (D. bako, D. buckleyana, D. irodensis, D. maciba, D. orangeana, D. pteropoda, D. sambiranensis subsp. bardotiae and subsp. sambiranensis, D. seriflora, and Dioscorea species Ovy valiha), were analyzed for their nutrient composition, compared with cultivated D. alata. They include 6/6 of the most favored wild edible yam species in Madagascar. New nutrient composition data (protein, carbohydrate/starch, energy, lipid, β-carotene, and minerals) are presented for these nine wild edible yam species. The results show that they contain comparable levels of lipids and starch to D. alata, but none are better sources of protein than D. alata. The results show that D. irodensis contains a significantly higher β-carotene content when compared to all other edible yams analyzed, and that D. buckleyana, D. irodensis, and D. sambiranensis subsp. bardotiae have a higher calcium content than cultivated D. alata, while all nine wild edible yam species analyzed contain a higher iron content, compared to cultivated D. alata. The nutrient composition data presented could provide new incentives to conserve wild edible yams and inform on strategies to select Dioscorea species for sustainable cultivation and use, providing opportunities to enhance future food security in Madagascar.

Diversity and distribution of Orchidaceae in one of the world's most threatened plant hotspots (Madagascar).

In recent decades, Madagascar has become one of the most important plant hotspots in the world. The country's remaining forests and vegetation are disappearing at an alarming rate, while dozens of new species are discovered each year. Amongst the plant families that have long been studied, Orchidaceae appear as one of the most charismatic, diverse and of high conservation concern. Based on a reviewed, comprehensive herbarium dataset, we have compiled a curated checklist of all orchid species occurring in Madagascar. Based on this complete dataset, we then compiled sampling effort, species diversity distribution and some general statistics on their ecology and IUCN conservation status. We compiled and standardised a global dataset using five public databases as the main data sources, supplemented by the most recent publications. The database contains ~ 10,000 geolocated records collected between 1816 and 2021. We used GIS software and rarefaction methods to examine sampling and diversity patterns. According to our dataset, there are currently 913 orchid species collected in Madagascar, of which 759 orchid species (83.1%) are endemic. Doubling the sampling effort could lead to the discovery of around 100 more species, bringing the total estimated number of orchid species in Madagascar to between 986 and 1048. About one-third (297 species) of all orchid species are known only by type specimens (189 species) or have not been collected in Madagascar for more than 50 years (214 species). Although the raw data show that the Andasibe-Moramanga area would have the highest orchid species concentration, our analysis of the data, adjusted for bias, shows that the centres of orchid diversity in Madagascar are in the Tsaratanàna Strict Nature Reserve and the Ranomafana National Park. Life-form statistics show that 55.0% of orchid species are strict epiphytes. The main flowering period of orchids in Madagascar is between November and March. To date, 84% of the 226 Malagasy orchid species listed in the IUCN Red List are threatened with extinction (CR, EN or VU). Despite geographically uneven coverage, the biodiversity of Malagasy orchids appears to be already well documented. We provide maps corrected for sampling bias that indicate priority areas for future surveys. Upcoming efforts should also focus on rediscovery and conservation of rare and/or threatened species and ensure that the protected area network is well aligned with the distribution of priority species for conservation. Finally, the conservation status of 75% of the orchid species found in Madagascar is not yet known and the inclusion of these species must be a top priority in the coming years.

A new species of Pandanus-dwelling frog from northern Madagascar related to Guibemantis pulcher.

Populations of phytotelmic frogs from northern Madagascar assigned to Guibemantis (Pandanusicola) pulcher are known to differ genetically from populations further south in the eastern rainforest belt of the island, but to date, their status has not been analyzed in depth. We combined molecular genetic data with an examination of color pattern to clarify the taxonomy of these frogs. DNA sequences of both mitochondrial and nuclear-encoded genes were consistently differentiated between the northern populations and those occurring further south. Uncorrected pairwise distance in the 16S rRNA gene was 3.7‒4.3% and thus at a level usually characterizing distinct frog species in Madagascar. Furthermore, the northern specimens were characterized by more and smaller purplish-brown spots on their green dorsal surface, and a less distinct brown patch on the flanks. Although fully conclusive evidence for the species status of the northern lineage from bioacoustic differences, sympatric occurrence or narrow hybrid zone is currently lacking, such species-level distinctness is currently the most likely hypothesis. We therefore name the northern populations as Guibemantis (Pandanusicola) pulcherrimus sp. nov. The new species is known from Makira (type locality) and Bemanevika, and specimens morphologically assignable to this taxon have also been recorded from Masoala, Marojejy and Anjanaharibe-Sud.

Wasp-mimicking soldier flies of the Australian Region: revision of Ampsalis Walker, Elissoma White and Lagenosoma Brauer (Stratiomyidae: Clitellariinae)

The genera Lagenosoma Brauer, 1882 (= Peratomastix Enderlein, 1914 syn. n.), Elissoma White, 1916 (= Pycnothorax Kertész, 1923 syn. n.) and Ampsalis Walker, 1859 (Stratiomyidae: Clitellariinae) are revised. Three species of Elissoma are redescribed (i.e., E. australis (Kertész, 1923) comb. n., E. brunnea, Hardy, 1933, and E. lauta White, 1916) and seven species are described as new. Similarly, three species of Lagenosoma are redescribed (i.e., L. dispar Brauer, 1882 (= Peratomastix australis Enderlein, 1914 syn. n.), L. pictum Brauer, 1882 and L. propinquum Brauer, 1882) and seven species are described as new. Ampsalis sensu lato is represented by two species in Indonesia and two species in Madagascar; here the Indonesian species are circumscribed as Ampsalis sensu stricto (i.e., A. geniata Walker, 1859 and A. iterabilis (Walker, 1859)) with two additional species described from northern Australia. Eudmeta Wiedemann, 1830 is diagnosed and a new synonymy identified (i.e., E. marginata (Fabricius, 1805) (= E. coerulemaculata Yang, Wei et Yang, 2010 syn. n.)). A revised key to Clitellariinae genera of the Oriental and Australian regions is presented, as well as keys to species of Ampsalis, Elissoma, Eudmeta and Lagenosoma.

A monograph of the African and Madagascan species of Cyperus sect. Incurvi (Cyperaceae)

SummaryCyperus sect. Incurvi (Cyperaceae) contains 31 species worldwide, with important continental radiations in Australasia, Tropical Africa and Madagascar, and the Neotropics. Here, a monograph of the African and Madagascan species of Cyperus sect. Incurvi is presented, including descriptions, illustrations, synonymy, notes on habitat and ecology, geographic distribution ranges and conservation assessments. Our results identify eight species of Cyperus sect. Incurvi endemic to Madagascar, and a further three species native to Tropical Africa. Seven species of Cyperus sect. Incurvi have been typified herein. Six rare Madagascan endemics are assessed as threatened with extinction.

A new Trogoderma from Madagascar (Coleoptera: Dermestidae: Megatominae), with a key to Madagascan species of the genus

Trogoderma banari Háva & Trýzna sp. nov., from central Madagascar is here described. Male genitalia are illustrated, and colour photographs of the species are provided. The new species differs from similar species by the combination of the following characters: colour of the elytral fasciae, the structure of the antennae, and the shape of the male genitalia. A key to the known Madagascan species of the genus Trogoderma is provided.

Species Diversity of Gelidium from Southern Madagascar Evaluated by an Integrative Taxonomic Approach

The diversity of red algae is significantly increasing; in the recent interest of climate changes, taxonomic and biogeographic studies are needed in untouched regions such as ecological important islands. We examined a collection of Gelidium specimens gathered during the 2010 Atimo Vatae expedition based on the morphology and DNA sequencing of mitochondrial cox1 and plastid rbcL. Both morphological and molecular datasets demonstrated the presence of three species in Madagascar; G. leptum G.H.Boo, L.Le Gall and H.S.Yoon, sp. nov., described here, and G. sclerophyllum W.R.Taylor and G. usmanghanii Afaq-Husain and Shameel. Gelidium leptum is distinguished by thin, slender, flattened thalli with irregular branches, compactly arranged thick-walled cells in medulla, sparse rhizoidal filaments at both sides of branches, and elongate sori of tetrasporangia. Gelidium sclerophyllum, previously considered as endemic to the Tropical Eastern Pacific, is first reported in the Indian Ocean and Hawai’i; G. usmanghanii, previously reported to occur in Pakistan and Oman, also presents a first record in the Southern Hemisphere. Phylogenies inferred from cox1 and rbcL sequences suggests that each of the three species likely diverged from different ancestors. The Madagascan Gelidium comprises two geographical elements; Madagascan endemic (G. leptum) and widespread species (G. sclerophyllum and G. usmanghanii).

Genus Diaparsis Förster (Hymenoptera: Ichneumonidae: Tersilochinae) from Madagascar: a review of the species with interstitial vein 2m-cu

Five species of the genus Diaparsis Förster characterized by the fore wing with interstitial vein 2m-cu are found to occur in Madagascar. One species, D. apophis sp. nov., is described as new to science; three species, D. interstitialis Khalaim, 2013, D. inusitata Khalaim, 2013 and D. voluptuosa Khalaim, 2013, are recorded from Madagascar for the first time. Diagnoses, references and general distribution to the five reviewed Madagascar species are given. Partial identification key to the species of Diaparsis occurring in Madagascar is provided.Diaparsis apophis sp. nov. is widely distributed through Madagascar from extreme north to south of the island; it was collected from Diana, Antananarivo, Androy, Analamanga, Vakinankaratra and Vatomandry provinces. The new species is easily distinguished from its Afrotropical congeners by the combination of interstitial vein 2m-cu in the fore wing; first metasomal tergite evenly arcuate in lateral view, round in cross-section centrally and entirely smooth; and black antennal flagellum with 33–37 flagellomeres in female and 30–40 flagellomeres in male. It is a rather large species with body length about 6.8 mm and fore wing length 4.2 mm. The species name derives from Apophis, an Ancient Egyptian god of chaos.

Time-lagged effects of habitat fragmentation on terrestrial mammals in Madagascar.

Biodiversity is severely threatened by habitat destruction. As a consequence of habitat destruction, the remaining habitat becomes more fragmented. This results in time-lagged population extirpations in remaining fragments when these are too small to support populations in the long term. If these time-lagged effects are ignored, the long-term impacts of habitat loss and fragmentation will be underestimated. We quantified the magnitude of time-lagged effects of habitat fragmentation for 157 nonvolant terrestrial mammal species in Madagascar, one of the biodiversity hotspots with the highest rates of habitat loss and fragmentation. We refined species' geographic ranges based on habitat preferences and elevation limits and then estimated which habitat fragments were too small to support a population for at least 100 years given stochastic population fluctuations. We also evaluated whether time-lagged effects would change the threat status of species according to the International Union for the Conservation of Nature (IUCN) Red List assessment framework. We used allometric relationships to obtain the population parameters required to simulate the population dynamics of each species, and we quantified the consequences of uncertainty in these parameter estimates by repeating the analyses with a range of plausible parameter values. Based on the median outcomes, we found that for 34 species (22% of the 157 species) at least 10% of their current habitat contained unviable populations. Eight species (5%) had a higher threat status when accounting for time-lagged effects. Based on 0.95-quantile values, following a precautionary principle, for 108 species (69%) at least 10% of their habitat contained unviable populations, and 51 species (32%) had a higher threat status. Our results highlight the need to preserve continuous habitat and improve connectivity between habitat fragments. Moreover, our findings may help to identify species for which time-lagged effects are most severe and which may thus benefit the most from conservation actions.

Are Madagascar's obligate grazing-lawns ancient and evolved with endemic herbivores, or recently selected by introduced cattle?

Are Madagascar's obligate grazing-lawns ancient and evolved with endemic herbivores, or recently selected by introduced cattle?

Identification of Priority Forest Conservation Areas for Critically Endangered Lemur Species of Madagascar

Forests have extraordinary importance for the conservation of endemic species in Madagascar. However, they are disappearing fast due to a number of pressures, notably unsustainable agricultural practices leading to aggravated status of biodiversity. Here, we used a number of ecological and spatial criteria to identify and prioritise unprotected forest areas for the conservation of the eight critically endangered species of lemur belonging to the Lemuridae family in Madagascar. By combining spatial information layers on the distribution areas of the studied lemurs, forest extension and conservation status, and potential human impacts (such as roads, human settlements and agriculture lands), it was possible to identify the most appropriate sites for the expansion of the conservation areas of critically endangered lemur species. Seven new sites, totalling over 33,000 ha, were identified as priority sites for the protection of those species. All of them were adjacent to or inside (just one site) existing protected areas (PAs), which likely makes their protection both feasible and socioeconomically efficient by enlarging those PAs. Legally protecting these sites would not only take Madagascar one little step ahead for meeting oncoming global biodiversity targets for 2030 but could also make a substantial contribution to the mid-term survival of the studied lemur species.

Re-circumscription of the mimosoid genus Entada including new combinations for all species of the phylogenetically nested Elephantorrhiza (Leguminosae, Caesalpinioideae, mimosoid clade).

Recent phylogenomic analyses of 997 nuclear genes support the long-held view that the genus Entada is congeneric with Elephantorrhiza. Entada is resolved as monophyletic only if the genus Elephantorrhiza is subsumed within it. The two genera were distinguished solely by relatively minor differences in the mode of dehiscence of the fruits (a craspedium separating into one-seeded endocarp segments in Entada versus a craspedium with the whole fruit valve breaking away from the persistent replum in Elephantorrhiza) and the craspedial fruit type itself provides a shared synapomorphy for the re-circumscribed Entada. Here, we provide a synopsis of Entada, including 11 new combinations in total, for the eight species, one subspecies and one variety previously placed in Elephantorrhiza, as well as a new combination for a subspecies of Entadarheedei Spreng. not previously dealt with when Entadapursaetha DC. was placed in synonymy. These new combinations are: Entadaburkei (Benth.) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadaelephantina (Burch.) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadagoetzei (Harms) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadagoetzeisubsp.lata (Brenan & Brummitt) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadaobliqua (Burtt Davy) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadapraetermissa (J.H. Ross) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadarangei (Harms) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadarheedeisubsp.sinohimalensis (Grierson & D.G. Long) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadaschinziana (Dinter) S.A. O'Donnell & G.P. Lewis, comb. nov.; Entadawoodii (E. Phillips) S.A. O'Donnell & G.P. Lewis, comb. nov.; and Entadawoodiivar.pubescens (E. Phillips) S.A. O'Donnell & G.P. Lewis, comb. nov. We provide a revised circumscription of the genus Entada which now comprises 40 species distributed pantropically, with the greatest diversity of species in tropical Africa. We present a complete taxonomic synopsis, including a map showing the global distribution of the genus and photographs showing variation amongst species in habit, foliage, flowers and fruits. A short discussion about extrafloral nectaries, mainly observed in the Madagascan species, is presented.

RADseq data reveal a lack of admixture in a mouse lemur contact zone contrary to previous microsatellite results.

Microsatellites have been a workhorse of evolutionary genetic studies for decades and are still commonly in use for estimating signatures of genetic diversity at the population and species level across a multitude of taxa. Yet, the very high mutation rate of these loci is a double-edged sword, conferring great sensitivity at shallow levels of analysis (e.g. paternity analysis) but yielding considerable uncertainty for deeper evolutionary comparisons. For the present study, we used reduced representation genome-wide data (restriction site-associated DNA sequencing (RADseq)) to test for patterns of interspecific hybridization previously characterized using microsatellite data in a contact zone between two closely related mouse lemur species in Madagascar (Microcebus murinus and Microcebus griseorufus). We revisit this system by examining populations in, near, and far from the contact zone, including many of the same individuals that had previously been identified as hybrids with microsatellite data. Surprisingly, we find no evidence for admixed nuclear ancestry. Instead, re-analyses of microsatellite data and simulations suggest that previously inferred hybrids were false positives and that the program NewHybrids can be particularly sensitive to erroneously inferring hybrid ancestry. Combined with results from coalescent-based analyses and evidence for local syntopic co-occurrence, we conclude that the two mouse lemur species are in fact completely reproductively isolated, thus providing a new understanding of the evolutionary rate whereby reproductive isolation can be achieved in a primate.

An integrative taxonomic revision and redefinition of Gephyromantis (Laurentomantis) malagasius based on archival DNA analysis reveals four new mantellid frog species from Madagascar

The subgenus Laurentomantis in the genusGephyromantiscontains some of the least known amphibian species of Madagascar. The six currently valid nominal species are rainforest frogs known from few individuals, hampering a full understanding of the species diversity of the clade. We assembled data on specimens collected during field surveys over the past 30 years and integrated analysis of mitochondrial and nuclear-encoded genes of 88 individuals, a comprehensive bioacoustic analysis, and morphological comparisons to delimit a minimum of nine species-level lineages in the subgenus. To clarify the identity of the speciesGephyromantis malagasius, we applied a target-enrichment approach to a sample of the 110 year-old holotype ofMicrophryne malagasiaMethuen and Hewitt, 1913 to assign this specimen to a lineage based on a mitochondrial DNA barcode. The holotype clustered unambiguously with specimens previously namedG. ventrimaculatus. Consequently we propose to considerTrachymantis malagasia ventrimaculatusAngel, 1935 as a junior synonym ofGephyromantis malagasius. Due to this redefinition ofG. malagasius, no scientific name is available for any of the four deep lineages of frogs previously subsumed under this name, all characterized by red color ventrally on the hindlimbs. These are here formally named asGephyromantis fiharimpesp. nov.,G. matsilosp. nov.,G. oelkrugisp. nov., andG. portonaesp. nov.The new species are distinguishable from each other by genetic divergences of >4% uncorrected pairwise distance in a fragment of the 16S rRNA marker and a combination of morphological and bioacoustic characters.Gephyromantis fiharimpeandG. matsilooccur, respectively, at mid-elevations and lower elevations along a wide stretch of Madagascar’s eastern rainforest band, whileG. oelkrugiandG. portonaeappear to be more range-restricted in parts of Madagascar’s North East and Northern Central East regions. Open taxonomic questions surroundG. horridus, to which we here assign specimens from Montagne d’Ambre and the type locality Nosy Be; andG. ranjomavo, which contains genetically divergent populations from Marojejy, Tsaratanana, and Ampotsidy.

Elevated CO2 moderates the impact of climate change on future bamboo distribution in Madagascar

The distribution of bamboo is sensitive to climate change and is also potentially affected by increasing atmospheric CO2 concentrations due to its C3 photosynthetic pathway. Yet the effect of CO2 in climate impact assessments of potential changes in bamboo distribution has to date been overlooked. In this study, we proposed a simple and quantitative method to incorporate the impact of atmospheric CO2 concentration into a species distribution modeling framework. To do so, we implemented 10 niche modeling algorithms with regionally downscaled climatic variables and combined field campaign observations. We assessed future climate impacts on the distribution of an economically and ecologically important and widely distributed bamboo species in Madagascar, and examined the effect of increasing CO2 on future projections. Our results suggested that future climatic changes negatively impact potential bamboo distribution in Madagascar, leading to a decline of 34.8% of climatic suitability and a decline of 63.6 ± 3.2% in suitable areas towards 2100 under RCP 8.5. However, increasing atmosphere CO2 offsets the climate impact for bamboo, and led to a smaller reduction of 19.8% in suitability and a potential distribution expansion of +111.6 ± 9.8% in newly suitable areas. We also found that the decline in climatic suitability for bamboo was related to increasing monthly potential evapotranspiration of the warmest quarter and minimum temperature of the warmest month. Conversely, the decreasing isothermality and increasing precipitation of the warmest quarter contributed to projected increase in bamboo-suitable areas. Our study suggested that elevated CO2 may mitigate the decrease in climatic suitability and increase bamboo-suitable areas, through enhancing water use efficiency and decreasing potential evapotranspiration. Our results highlight the importance of accounting for the CO2 effect on future plant species distributions, and provide a mechanistic approach to do so for ecosystems constrained by water.