| 1. |
- Ralimanana, H., et al.
(författare)
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Madagascar’s extraordinary biodiversity: Threats and opportunities
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623
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Forskningsöversikt (refereegranskat)abstract
- Madagascar’s unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar’s terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.
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| 2. |
- Antonelli, Alexandre, 1978, et al.
(författare)
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Madagascar's extraordinary biodiversity : Evolution, distribution, and use
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623, s. 962-
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Tidskriftsartikel (refereegranskat)abstract
- Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique " living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.
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| 3. |
- Buerki, Sven, et al.
(författare)
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Phylogeny and circumscription of Sapindaceae revisited : molecular sequence data, morphology and biogeography support recognition of a new family, Xanthoceraceae
- 2010
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Ingår i: Plant Ecology and Evolution. - : Agentschap Plantentuin Meise. - 2032-3913 .- 2032-3921. ; 143:2, s. 148-159
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Tidskriftsartikel (refereegranskat)abstract
- Background and aims Recent studies have adopted a broad definition of Sapindaceae that includes taxa traditionally placed in Aceraceae and Hippocastanaceae, achieving monophyly but yielding a family difficult to characterize and for which no obvious morphological synapomorphy exists. This expanded circumscription was necessitated by the finding that the monotypic, temperate Asian genus Xanthoceras, historically placed in Sapindaceae tribe Harpullieae, is basal within the group. Here we seek to clarify the relationships of Xanthoceras based on phylogenetic analyses using a dataset encompassing nearly 3/4 of sapindaceous genera, comparing the results with information from morphology and biogeography, in particular with respect to the other taxa placed in Harpullieae. We then re-examine the appropriateness of maintaining the current broad, morphologically heterogeneous definition of Sapindaceae and explore the advantages of an alternative family circumscription. Methods Using 243 samples representing 104 of the 142 currently recognized genera of Sapindaceae s. lat. (including all in Harpullieae), sequence data were analyzed for nuclear (ITS) and plastid (matK, rpoB, trnD-trnT, trnK-matK, trnL-trnF and trnS-trnG) markers, adopting the methodology of a recent family-wide study, performing single-gene and total evidence analyses based on maximum likelihood (ML) and maximum parsimony (MP) criteria, and applying heuristic searches developed for large datasets, viz, a new strategy implemented in RAxML (for ML) and the parsimony ratchet (for MP). Bootstrap analyses were performed for each method to test for congruence between markers. Key results Our findings support earlier suggestions that Harpullieae are polyphyletic: Xanthoceras is confirmed as sister to all other sampled taxa of Sapindaceae s. lat.; the remaining members belong to three other clades within Sapindaceae s. lat., two of which correspond respectively to the groups traditionally treated as Aceraceae and Hippocastanaceae, together forming a clade sister to the largely tropical Sapindaceae s. str., which is monophyletic and morphologically coherent provided Xanthoceras is excluded. Conclusion To overcome the difficulties of a broadly circumscribed Sapindaceae, we resurrect the historically recognized temperate families Aceraceae and Hippocastanaceae, and describe a new family, Xanthoceraceae, thus adopting a monophyletic and easily characterized circumscription of Sapindaceae nearly identical to that used for over a century.
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| 4. |
- Swenson, Ulf, 1959-, et al.
(författare)
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Island life - classification and cryptic species of Pycnandra (Sapotaceae) in New Caledonia
- 2015
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Ingår i: Botanical journal of the Linnean Society. - 0024-4074 .- 1095-8339. ; 179, s. 57-77
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Tidskriftsartikel (refereegranskat)abstract
- Pycnandra (Sapotaceae), the largest endemic genus in New Caledonia, comprises 66 species classified in six subgenera. We tested phylogenetic relationships and a proposed infrageneric classification by sampling 60 species for sequences of nuclear ribosomal DNA (ETS, ITS, RPB2) and plastid DNA (trnH–psbA) and nine morphological characters. Data were analysed with Bayesian inference, parsimony jackknifing and lineage through time. We recovered a phylogenetic tree supporting the recognition of six proposed subgenera (Achradotypus, Leptostylis, Pycnandra, Sebertia, Trouettia and Wagapensia). Because a subgeneric classification is used, the nomenclature will be stable when the members are transferred to Pycnandra. Morphological traits were optimized in the BEAST analysis, adding evidence to earlier work that morphology has limited value for successfully diagnosing groups in Sapotaceae. We confirm a previously suspected case of cryptic species that exhibit the same morphological features and require the same abiotic conditions, but are distantly related in the phylogenetic tree. We detected two possible new cases of cryptic sibling species that might warrant recognition. A slowdown in speciation rate in several genera has been suggested as evidence that New Caledonia was once submerged after rifting from Australia. Plotting lineages through time reveals two important intervals at 7.5–8.6 Ma and present to 1.5 Ma, when net molecular diversification within the genus was zero. This indicates that the genus presently has reached a dynamic equilibrium, providing additional evidence that New Caledonia is an old Darwinian island, being submerged during the Eocene and colonized after re-emergence c. 37 Ma.
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| 5. |
- Swenson, Ulf, 1959-, et al.
(författare)
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Reassessment of generic boundaries in Neotropical Chrysophylloideae (Sapotaceae) : Eleven reinstated genera and narrowed circumscriptions of Chrysophyllum and Pouteria
- 2023
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Ingår i: Taxon. - : John Wiley & Sons. - 0040-0262 .- 1996-8175. ; 72:2, s. 307-359
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Tidskriftsartikel (refereegranskat)abstract
- Classifications of the pantropical plant family Sapotaceae based solely on morphology have historically recognized between 125 and 53 genera. Phylogenetic analyses using molecular data have repeatedly demonstrated that broad concepts of two large genera belonging to subfamily Chrysophylloideae, Chrysophyllum and Pouteria, are untenable and their narrowed delimitations have restricted them to the Neotropics. A recent phylogenetic study proposed further amendments by resurrecting the genera Achrouteria, Cornuella, Lucuma, Martiusella, Nemaluma, Prieurella and Ragala, and questioned the status of three generally accepted genera, Chromolucuma, Pradosia and Sarcaulus. We test this suggested classification using expanded sampling that comprises 122 terminals, including material of 29 of the 34 name-bringing species for generic names historically regarded as synonyms of Chrysophyllum and Pouteria. We used sequence data from ribosomal nrDNA (ETS, ITS), the nuclear gene RPB2, two cpDNA spacers (petN-psbM, trnH-psbA), and indel information to estimate phylogenetic relationships in a Bayesian framework using BEAST. All sequences were newly realigned to test reproducibility, and 26 morphological characters were mapped on the resulting tree. Our analyses recovered three African genera embedded within a large Neotropical clade of Chrysophylloideae. We found strong support for the reinstatement of the seven genera listed above as well as for four other genera, viz. Chloroluma, Englerella, Labatia, and Peteniodendron. This subsequently leads to further amendments of Chrysophyllum and Pouteria, which are now limited to include 25-30 and 7 species, respectively. However, one clade that includes many name-bringing lineages largely corresponds to Pouteria s.l., a group that needs further phylogenetic research to unravel relationships and generic limits. The hypothesis that Chrysophyllum cuneifolium had an inter-continental hybrid origin involving genomes from Africa and South America is rejected because it is shown to have been based on erroneous results obtained from a contaminated DNA aliquot. A total of 73 genera are currently recognised in Sapotaceae, 21 of which are Neotropical members of Chrysophylloideae. We update the nomenclature and synonymy of 75 species, make 36 new combinations, and designate lectotypes for 31 names.
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| 6. |
- Swenson, Ulf, 1959-, et al.
(författare)
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Resolving the relationships of the enigmatic genera Beauvisagea and Boerlagella, and the position of Planchonella suboppositifolia
- 2020
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 69, s. 998-1015
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Tidskriftsartikel (refereegranskat)abstract
- ThepantropicalplantfamilySapotaceaecurrentlyincludes65–70genera.Twogenera,BeauvisageaandBoerlagella,were described in 1890s using incomplete material from West New Guinea (Bird’s Head Peninsula) and Sumatra, neither of which has been collected since. Their systematic position has long been regarded doubtful and Boerlagella was once placed in its own family, Boer- lagellaceae. We show here how useful and important it can be to obtain small leaf fragments from type specimens that are up to 150 years old for molecular analysis aiming to determine their phylogenetic position and clarify their taxonomic status. We used nuclear ribosomal DNA (ETS, ITS) and the nuclear gene RPB2 from 170 terminals to estimate phylogenetic relationships in a Bayes- ian framework using BEAST. The old type material yielded full length sequences of ETS and ITS from both genera (less successful with RPB2), revealing that both are firmly placed in Planchonella. Boerlagella is placed in synonymy with Planchonella and its type is accepted as Planchonella spectabilis, a species from Sumatra that possibly has gone extinct due to deforestation. Beauvisagea from the Bird’s Head Peninsula of western New Guinea is likewise regarded as a synonym of Planchonella and its type, accepted as P. pomi- fera, is conspecific with Pouteria doonsaf (currently circumscribed to include material of at least two different species), not Plancho- nella maclayana as earlier believed. Our study also included Planchonella suboppositifolia, an odd species with a character combination in conflict with the current definition of the genus. Our results show that it is sister to a lineage comprising several gen- era, including Planchonella, and that it represents a distinct lineage constituting a monotypic genus that will be described in a sub- sequent paper. The most recent classification of subfamily Chrysophylloideae and the character combinations used to distinguish its constituent genera are supported, and our results confirm that taxa can reliably be assigned to a genus based on morphology alone.
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