Malagasy Species Research Articles

Rearranging Specimens on Herbarium Type Sheets of Streptocarpus betsiliensis Humbert (Gesneriaceae)

Abstract Moller, M., K. Nishii, M. W. Callmander, P. B. Phillipson & O. Poncy (2015). Rearranging specimens on herbarium type sheets of Streptocarpus betsiliensis Humbert (Gesneriaceae). Candollea 70: 145–150. In English, English and French abstracts. During recent herbarium research on the Malagasy species of Gesneriaceae, a hitherto undetected mixed collection of the type of Streptocarpus betsiliensis Humbert (Perrier de la Bâthie 12482), was observed at the Paris herbarium (P). Of the three sheets present, one, the holotype [P00088746], comprised only Streptocarpus betsiliensis specimens, while the two isotypes, [P00088747, P00088748], were found to comprise a mixture of this species and a closely related and easily confused species, Streptocarpus lanatus MacMaster. As a result of this, the specimens on the mixed sheets were physically separated and the collections were distinguished by the suffixes A and B. They were then remounted to form species-specific sheets, rescanned, and the databases at P upd...

Searching for the oldest baobab of Madagascar: radiocarbon investigation of large Adansonia rubrostipa trees.

We extended our research on the architecture, growth and age of trees belonging to the genus Adansonia, by starting to investigate large individuals of the most widespread Malagasy species. Our research also intends to identify the oldest baobabs of Madagascar. Here we present results of the radiocarbon investigation of the two most representative Adansonia rubrostipa (fony baobab) specimens, which are located in south-western Madagascar, in the Tsimanampetsotse National Park. We found that the fony baobab called “Grandmother” consists of 3 perfectly fused stems of different ages. The radiocarbon date of the oldest sample was found to be 1136 ± 16 BP. We estimated that the oldest part of this tree, which is mainly hollow, has an age close to 1,600 yr. This value is comparable to the age of the oldest Adansonia digitata (African baobab) specimens. By its age, the Grandmother is a major candidate for the oldest baobab of Madagascar. The second investigated specimen, called the “polygamous baobab”, consists of 6 partially fused stems of different ages. According to dating results, this fony baobab is 1,000 yr old. This research is the first investigation of the structure and age of Malagasy baobabs.

Diversification of Dombeyoideae (Malvaceae) in the Mascarenes: Old Taxa on Young Islands?

Premise of research. The patterns of diversification of Mascarene taxa remain largely unknown in comparison to other insular systems. Traditional interpretations of insular radiations often assume that endemic taxa radiated after the origin of the insular habitats on which they were established. The Dombeyoideae (Malvaceae) sublineage endemic to Mauritius and Réunion in the Mascarenes is an ideal model to test for the signature of insular diversification.Methodology. We combined molecular sequences for a dense sample of Mascarene dombeyoids together with African, Malagasy, and Asian outgroup species. We estimated divergence times based on two calibration schemes (including or excluding geological calibration). Comparative phylogenetic methods were used to study the diversification rates and the evolution of the floral disparity in the Mascarene clade.Pivotal results. Excluding geological constraints resulted in drastically older age estimates than when we included such calibrations. Diversification patterns suggest a decrease of diversification rates through time. The low morphological disparity indicates an early partitioning of floral characters.Conclusions. The lineage diversification and the morphological disparity are consistent with traditional scenarios of insular radiation. However, the Mascarene clade is older than Réunion and Mauritius, suggesting the onset of radiation before the formation of the archipelago. The diversification might have been driven by geographical opportunity rather than ecological opportunity.

Forest aboveground biomass estimates in a tropical rainforest in Madagascar: new insights from the use of wood specific gravity data

To generate carbon credits under the Reducing Emissions from Deforestation and forest Degradation program (REDD+), accurate estimates of forest carbon stocks are needed. Carbon accounting efforts have focused on carbon stocks in aboveground biomass (AGB). Although wood specific gravity (WSG) is known to be an important variable in AGB estimates, there is currently a lack of data on WSG for Malagasy tree species. This study aimed to determine whether estimates of carbon stocks calculated from literature-based WSG values differed from those based on WSG values measured on wood core samples. Carbon stocks in forest biomass were assessed using two WSG data sets: (i) values measured from 303 wood core samples extracted in the study area, (ii) values derived from international databases. Results suggested that there is difference between the field and literature-based WSG at the 0.05 level. The latter data set was on average 16 % higher than the former. However, carbon stocks calculated from the two data sets did not differ significantly at the 0.05 level. Such findings could be attributed to the form of the allometric equation used which gives more weight to tree diameter and tree height than to WSG. The choice of dataset should depend on the level of accuracy (Tier II or III) desired by REDD+. As higher levels of accuracy are rewarded by higher prices, species-specific WSG data would be highly desirable.

Adaptive morpho-traits, taxonomy and biogeography of Metania Gray, 1867 (Porifera: Spongillina: Metaniidae) with the description of a new species from Madagascar.

A comparative analysis of gemmular architecture adaptive morpho-traits at family level is reported for Metaniidae together with the discovery and description of a new species from the River Mangoky (High Plateau), Madagascar. The new Malagasy species, ascribed to Metania for diagnostic traits of the skeleton and the gemmular architecture, differs from all the other known species of the genus in its unique combination of diagnostic traits. Metania madagascariensis sp. nov. is characterised by encrusting growth form, conulose surface, specialized ectosomal skeleton, alveolate-reticulate choanosomal skeleton, two types of megascleres as smooth oxeas (α) and acanthoxeas (β) ornamented with spines and/or tubercles, one type of microsclere as acanthoxeas with dense spines/tubercles bearing rosettes of microspines at tips; gemmules with or without cage of megascleres and frequently surrounded by microscleres; gemmular theca trilayered with pneumatic layer of fibrous spongin, boletiform (trumpet-like) gemmuloscleres with proximal true rotule large, smooth and with irregular blunt margins, and distal knob-like pseudorotule notably smaller, with a few hooks at the margins. M. madagascariensis belongs to the Afrotropical species group of Metania. Identification keys and an annotated checklist at global level are also provided together with a species-level discussion of Metania focusing on morphology, taxonomy, nomenclature and biogeography.

Two New Species of Xyris L. (Xyridaceae) Endemic to Madagascar with a Key to the Malagasy Species

Abstract Rakotonirina, N., M. W. Callmander, P. B. Phillipson & J. M. Lock (2014). Two new species of Xyris L. (Xyridaceae) endemic to Madagascar with a key to the Malagasy species. Candollea 69: 171–178. In English, English and French abstracts. A review of the available herbarium material and of the currently recorded species of the genus Xyris L. (Xyridaceae) from Madagascar in the context of the “Catalogue of the Vascular Plants of Madagascar” project has led us to identify two new species which are described here as: Xyris labatii Rakoton., Callm. & Phillipson and Xyris marojejyensis Lock, Rakoton., Callm. & Phillipson. This brings the total number of species that we recognize on the island to seven. A key to the Malagasy species of Xyris, illustrations of the new species and a discussion of their morphological affinities are provided, together with preliminary conservation status assessments following IUCN Red List Categories and Criteria.

Philopotaminae of Madagascar (Trichoptera: Philopotamidae)

SummaryThe Malagasy fauna includes two genera of Philopotaminae: Wormaldia McLachlan 1865 and an endemic new genus, Ranarijaodes n. gen. The Malagasy and African (sensu stricto) lineages of Wormaldia are distinct. Apomorphic characters (the shape of the phallic apparatus for the African species and the splitting of the median lobe of the tenth tergite for the Malagasy species) confirm their separation. New captures are reported for two of the four previously known species of Wormaldia. Seven new species are described: Wormaldia ambahibeae n. sp., W. faharoa n. sp., W. fahatelo n. sp., W. randriamasimananai n. sp., W. fahefatra n. sp., W. legrandi n. sp. and W. fahadimy n. sp. Ranarijaodes n. gen. is close to Dolophilodes Ulmer 1909. It is described for the three new species Ranarijaodes fiana n. sp., R. angapi n. sp. and R. atsimo n. sp. The 14 Malagasy species of Philopotaminae are endemics of the island. Their geographical distributions and ecological preferences are described and discussed.

Correction: Paraphyly of the Subgenus Sintonius (Diptera, Psychodidae, Sergentomyia): Status of the Malagasy Species. Creation of a New Subgenus and Description of a New Species

The type-species is not designated in the published article. The type-species should appear in the Results as: “Type-species of this new subgenus: Sergentomyia huberti comb. nov.”

A taxonomic mystery for more than 150 years: Identity, systematic position and Malagasy origin of the snake Elapotinus picteti Jan, 1862, and synonymy of Exallodontophis Cadle, 1999 (Serpentes: Lamprophiidae).

Elapotinus picteti Jan, 1862 is an enigmatic snake taxon that has been described without locality data. Genus and species, both based on the unique holotype, were considered to belong to the venomous African Aparallactinae for more than a century, but although this taxon was never rediscovered it was accepted as a valid species until present. To clarify the taxonomic status of E. picteti its characters were compared with literature and determination keys for the whole world. This literature survey and the subsequent study of type specimens revealed that the monotypic Elapotinus is a subjective senior synonym of the monotypic Malagasy pseudoxyrhophiine snake genus Exallodontophis Cadle, 1999 which is characterized by its unique aglyphous dentition. We therefore transfer Elapotinus from the lamprophiid subfamily Aparallactinae to the subfamily Pseudoxyrhophiinae. Furthermore, Elapotinus picteti strongly resembles the Malagasy species Exallodontophis albignaci (Domergue, 1984) in external morphology, coloration and dentition. As a consequence we consider Elapotinus picteti a subjective senior synonym of Exallodontophis albignaci.

Phylogeny and generic limits in the sister tribes Psychotrieae and Palicoureeae (Rubiaceae): Evolution of schizocarps in Psychotria and origins of bacterial leaf nodules of the Malagasy species.

• Premise of the study: The pantropical, species-rich Psychotrieae and Palicoureeae are sister tribes of mostly drupe-bearing and nonbacterial leaf-nodulating species with problematic generic limits. This problem is more complicated in Psychotrieae due to the paraphyly of the genus Psychotria, the lack of diagnostic characters for some major lineages, and the poor sampling from some biodiversity hotspots. Schizocarps and bacterial leaf nodules have been used for recognizing formal groups in Psychotrieae, but their evolution and taxonomic value have not been studied using a robust phylogeny of the tribe.• Methods: We analyzed 287 samples from the entire ranges of the tribes, with particular emphasis on the Western Indian Ocean region, with the Bayesian Markov chain Monte Carlo method.• Key results: All allied Psychotria genera investigated are nested within a paraphyletic Psychotria. Schizocarps evolved independently two times within Psychotria, and one reversal back to the drupaceous condition is inferred. The Malagasy leaf-nodulated Psychotrieae (except Apomuria bullata) and the Comorian non-leaf-nodulated Psychotria conocarpa are nested within the (African) leaf-nodulated clade. Within Palicoureeae, Chassalia is paraphyletic with respect to Geophila sensu stricto, and the Malagasy Geophila gerrardii and the African Hymenocoleus are closely related.• Conclusions: A widely circumscribed Psychotria encompassing the entire Psychotrieae is supported. Within Psychotria, two separate origins of schizocarps from drupes, one reversal back to the drupaceous condition, and two independent origins of the Malagasy leaf-nodulated species are inferred. A new genus Puffia is described to accommodate Geophila gerrardii, and a narrow circumscription of Chassalia is adopted. Thirty-two new combinations, two lectotypifications, and 25 new names are presented.

Paraphyly of the subgenus Sintonius (Diptera, Psychodidae, Sergentomyia): status of the Malagasy species. Creation of a new subgenus and description of a new species.

During an inventory of Phlebotomine sand flies carried out in Madagascar, we have identified some specimens showing morphological characters related to the subgenus Sintonius of the genus Sergentomyia. We started a molecular study based on cytochrome b mtDNA and on D1–D2 and D8 domains of the rDNA. The sampling includes all the Sergentomyia species available and also S. (Sergentomyia) schwetzi, S. (Parrotomyia) magna, and the following species belonging to the subgenus Sintonius: S. clydei, S. christophersi, S. affinis vorax, S. adleri and S. meilloni. The Sintonius subgenus (sensu Theodor) is paraphyletic. The Malagasy specimens morphologically Sintonius-like are never clustered with the continental Sintonius. We propose a new subgenus to include them: Trouilletomyia subg. nov. Due to the lack of mesanepisternal setae, the species huberti is removed from the genus Phlebotomus and we propose here a new combination: Sergentomyia huberti comb. nov. The male of S. huberti is pinpointed and described for the first time. Lastly, a new species for Science is described on one female: Sergentomyia (Trouilletomyia) boironis n. sp.

Four new species of the genus Cheimacheramus Barnard, 1934 from Madagascar (Trichoptera: Sericostomatidae)

The genus Cheimacheramus Barnard, 1934 included only three species, one from South Africa and two from Madagascar. Four new Malagasy species are described herein: Cheimacheramus akandi sp. n., Cheimacheramus barnardi sp. n. and Cheimacheramus anjojorobensis sp. n. from the Anjojorobe Forest, Cheimacheramus madecassus sp. n. from the Lakato Forest and the Marojejy National Park. Diagnostic characters of the genus and species are discussed and illustrated. In Madagascar, these discoveries confirm the localization of the genus within the eastern evergreen forests.http://zoobank.org/urn:zoobank.org:pub:79472077-04E9-42FA-B55B-9EE291556E60

A revision of the ant genus Mystrium in the Malagasy region with description of six new species and remarks on Amblyopone and Stigmatomma (Hymenoptera, Formicidae, Amblyoponinae)

The genus Mystrium is revised for the Malagasy region. Six species, Mystrium barrybressleri sp. n., Mystrium labyrinth sp. n., Mystrium eques sp. n., Mystrium mirror sp. n., Mystrium shadow sp. n., and Mystrium janovitzi sp. n. are described as new. Two existing names, Mystrium fallax Forel and Mystrium stadelmanni Forel, are synonymized with Mystrium voeltzkowi Forel and Mystrium mysticum Roger, respectively. All recognized species, including species outside of the Malagasy region, are assigned to one of the three newly proposed species groups. The associations between existing names and males are reexamined, and males of eight of the ten Malagasy species are described or redescribed. The taxonomic history of Mystrium highlights the importance of using unique identifiers when designating type specimens and the use of deposited vouchers in phylogenetic and ecological studies. Keys to species for workers, queens, and males are provided. Furthermore, a neotype for Mystrium mysticum is designated, as well as lectotypes for Mystrium camillae Emery, Mystrium rogeri Forel, Mystrium fallax Forel, Mystrium oberthueri Forel, Mystrium stadelmanni Forel, and Mystrium voeltzkowi Forel. Stigmatomma gingivale (Brown) is reassigned to Amblyopone as comb. rev. and Amblyopone awa Xu & Chu, Amblyopone kangba Xu & Chu, Amblyopone meiliana Xu & Chu, and Amblyopone zomae Xu & Chu are transferred to the genus Stigmatomma as comb. n.

Biochemical and nutritional properties of baobab pulp from endemic species of Madagascar and the African mainland

The fruit of baobab (Adansonia sp.) is well known in Africa both for its medicinal properties and social uses. It is a very promising tropical fruit although it has been little investigated and exploited in Madagascar. One of the major challenges, in Africa, in the last years has been to establish the baobab as a commercial crop with an economic value. In order to know if Malagasy baobab fruits have the same potential, we proposed to study biochemical characteristics of its fruit pulp. To achieve this objective, five endemic baobab species from Madagascar and one from Cote d’Ivoire were studied. Contents in vitamin C, polyphenols, lipids, proteins and minerals were evaluated. The biochemical composition of the fruit pulp of Madagascar species was studied and compared to that of a SudanoSahelian species (Adansonia digitata). Results showed high variability in biochemical characteristics and mineral content between the five Malagasy species and the Sudano-Sahelian species. These data revealed that the composition and the interesting nutritional potential of the baobab pulp may be of high interest to Malagasy consumers, which would contribute to rank it as a commercial crop.

A taxonomic revision of Anisophyllea (Anisophylleaceae) from Madagascar

A taxonomic revision of Anisophyllea (Anisophylleaceae) from Madagascar was carried out. Five species of the genus are recognized, of which four are described as new. The five species include Anisophyllea fallax, A. madagascarensis sp. nov., A. masoalensis sp. nov., A. parafallax sp. nov., and A. schatzii sp. nov. A key to the Malagasy species of Anisophyllea is provided. All species are described and illustrated. Information on their distribution and habitat is given. Taxonomic issues are discussed. The IUCN Red List categories are assessed.

Nuclear microsatellite variation in Malagasy baobabs (Adansonia, Bombacoideae, Malvaceae) reveals past hybridization and introgression

Adansonia comprises nine species, six of which are endemic to Madagascar. Genetic relationships between the Malagasy species remain unresolved due to conflicting results between nuclear and plastid DNA variation. Morphologically intermediate individuals between distinct species have been identified, indicative of interspecific hybridization. In this paper, microsatellite data are used to identify potential cases of hybridization and to provide insights into the evolutionary history of the genus on Madagascar. Eleven microsatellites amplified with new primers developed for Adansonia rubrostipa were used to analyse 672 individuals collected at 27 sites for the six Malagasy species and morphologically intermediate individuals. Rates of individual admixture were examined using three Bayesian clustering programs, STRUCTURE, BAPS and NewHybrids, with no a priori species assignment. Population differentiation was coherent, with recognized species boundaries. In the four Malagasy species of section Longitubae, 8·0, 9·0 and 9·5 % of individuals with mixed genotypes were identified by BAPS, NewHybrids and STRUCTURE, respectively. At sites with sympatric populations of A. rubrostipa and A. za, NewHybrids indicated these individuals to be F2 and, predominantly, backcrosses with both parental species. In northern Madagascar, two populations of trees combining A. za and A. perrieri morphology and microsatellite alleles were identified in the current absence of the parental species. The clear genetic differentiation observed between the six species may reflect their adaptation to different assortments of climate regimes and habitats during the colonization of the island. Microsatellite variation reveals that hybridization probably occurred in secondary contact between species of section Longitubae. This type of hybridization may also have been involved in the differentiation of a local new stabilized entity showing specific microsatellite alleles and morphological characters, suggesting a potential role of hybridization in the recent history of diversification on Madagascar.

A new subgenus of Ceraclea Stephens 1829: Ranaivodes n. subg., endemic to Madagascar, with description of four new species (Trichoptera: Leptoceridae)

SummaryRanaivodes, new subgenus of Ceraclea, is described from Madagascar. It is closely related to the South Saharan endemic subgenus Pseudoleptocerus Ulmer. Ranaivodes is characterized by the presence of the harpago and the absence of the phallic parameres. Pseudoleptocerus is characterized by the presence of scales on the wings and two pairs of parameres at the phallic apparatus. Four new species are described: Ceraclea (Ranaivodes) sartorii n. sp., Ceraclea (Ranaivodes) higleri n. sp., Ceraclea (Ranaivodes) ifarantsae n. sp. and Ceraclea (Ranaivodes) jonathani n. sp. Homilia grandis Mosely, described from Madagascar, is transferred from the genus Homilia to the genus Ceraclea and to the subgenus Ranaivodes comb. nov. This new subgenus is endemic of the Island and includes all the known Malagasy species of Ceraclea. The geographic distributions of the species are studied and analyzed according to ecological parameters.

Phlebotomine sand flies from Madagascar (Diptera: Psychodidae). VIII — Phlebotomus (Anaphlebotomus) vincenti n. sp.

A new species of Phlebotomine sand fly (Diptera: Psychodidae) is described from Mikea Forest in the southwest of Madagascar: Phlebotomus vincenti n. sp. It is temporarily classified in the subgenus Anaphlebotomus according to its spermathecal organization, similar to those of P. berentiensis, P. fertei and P. vaomalalae, previously classified in the subgenus Anaphlebotomus referring to on male genitalia morphology. An original trumpet-like dilatation on the distal part of the spermathecal ducts individualizes P. vincenti n. sp. from the other Malagasy species. Moreover, the second internal transcribed spacer (ITS2) sequences strongly individualises P. vincenti n. sp. from the other Malagasy Phlebotomus.

Vulnerability of baobab species to climate change and effectiveness of the protected area network in Madagascar: Towards new conservation priorities

Baobab species are representative of the high biodiversity and endemism rates that place Madagascar in the top three of the countries with the highest biodiversity in the world. In this study, we estimated the vulnerability of three endangered Malagasy baobab species (Adansonia grandidieri Baill., Adansonia perrieri Capuron and Adansonia suarezensis H. Perrier) to climate change and the effectiveness of the protected area network (PAN) for the future conservation of these species. To estimate the environmental niche of the species, we used an original data-set based on satellite image analysis to detect species presence and an ensemble modelling approach using three species distribution models (GLM, GAM and MaxEnt). We projected the species distribution in 2050 and 2080 using an ensemble forecasting approach combining the three species distribution models and three global circulation models for climate projections. Measures of connectivity were employed to assess the present and future effectiveness of the existing PAN. Among the three baobab species studied, two are severely threatened by climate change (A. perrieri and A. suarezensis), in part because the present PAN does not overlap with future species distribution areas. Recently, strong efforts have been made in designing an optimised PAN to conserve Madagascar outstanding biodiversity. Nevertheless, its future effectiveness is questioned by the potential shifts in species distributions due to predicted changes in climate. In the context of climate change, alternative strategies such as ecological restoration would also have to be adopted to conserve biodiversity in Madagascar.

Coloured and Toxic Nectar: Feeding Choices of the Madagascar Giant Day Gecko, Phelsuma grandis

AbstractColoured nectar is a rare phenomenon best known from islands and insular habitats. Islands are also known for lizard pollination, where coloured nectar potentially acts as a visual cue to attract pollinators, advertising the sweet reward. However, nectar may also contain secondary metabolites with toxic or deterrent effects. The aim of this study was to determine which factors are important as artificial nectar choice determinants to the Madagascar giant day gecko, Phelsuma grandis, an island pollinator: artificial nectar colour, artificial nectar colour saturation, artificial nectar conspicuousness and/or the presence of the alkaloid nicotine. Coloured artificial nectar and the darkest artificial nectar colour saturation were found to be important visual cues for the geckos, while the contrast between artificial nectar and petal colour was not. Geckos were deterred only by high nicotine concentrations (1000 μm in 0.63 m sucrose) and may even prefer low nicotine concentrations to sucrose‐only solutions. Given their overall fondness for sugar solutions, Madagascar giant day geckos are likely to be important pollinators of Malagasy plant species that produce enough nectar to attract them, and plants with coloured nectar and/or secondary metabolites may have evolved those traits to attract the geckos in particular.