| 1. |
- Andriamihajarivo, Tefy H., et al.
(författare)
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Phyllopentas flava (Rubiaceae), a New Morphologically Heterodistylous and Functionally Dioecious Species from Madagascar
- 2011
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Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 36:4, s. 1024-1027
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Tidskriftsartikel (refereegranskat)abstract
- A new species of the Afro-Malagasy genus Phyllopentas Karehed & B. Bremer, Phyllopentas flava Razafim., T. Andriam. et Karehed, is described and illustrated. This plant is restricted to the Itremo region in southeastern Madagascar and is distinct morphologically from the other species of the genus by its pubescent, narrowly ovate to narrowly elliptic leaves, grey-whitish and thickly hairy midribs and secondary veins on the lower surfaces of leaves, and functionally dioecious and heterodistylous flowers. Summaries of distribution, phenology, habitat, and ecology are given and a conservation assessment is also provided.
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| 2. |
- Appelhans, Marc S., et al.
(författare)
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Age and historical biogeography of the pantropically distributed Spathelioideae (Rutaceae, Sapindales)
- 2012
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:7, s. 1235-1250
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Tidskriftsartikel (refereegranskat)abstract
- Aim The family Rutaceae (rue family) is the largest within the eudicot order Sapindales and is distributed mainly in the tropical and subtropical regions of both the New World and the Old World, with a few genera in temperate zones. The main objective of this study is to present molecular dating and biogeographical analyses of the subfamily Spathelioideae, the earliest branching clade (which includes eight extant genera), to interpret the temporal and spatial origins of this group, ascertaining possible vicariant patterns and dispersal routes and inferring diversification rates through time. Location Pantropics. Methods A dataset comprising a complete taxon sampling at generic level (83.3% at species level) of Spathelioideae was used for a Bayesian molecular dating analysis (beast). Four fossil calibration points and an age constraint for Sapindales were applied. An ancestral area reconstruction analysis utilizing the dispersalextinctioncladogenesis model and diversification rate analyses was conducted. Results Dating analyses indicate that Rutaceae and Spathelioideae are probably of Late Cretaceous origin, after which Spathelioideae split into a Neotropical and a Palaeotropical lineage. The Palaeotropical taxa have their origin inferred in Africa, with postulated dispersal events to the Mediterranean, the Canary Islands, Madagascar and Southeast Asia. The lineages within Spathelioideae evolved at a relatively constant diversification rate. However, abrupt changes in diversification rates are inferred from the beginning of the Miocene and during the Pliocene/Pleistocene. Main conclusions The geographical origin of Spathelioideae probably lies in Africa. The existence of a Neotropical lineage may be the result of a dispersal event at a time in the Late Cretaceous when South America and Africa were still quite close to each other (assuming that our age estimates are close to the actual ages), or by Gondwanan vicariance (assuming that our age estimates provide minimal ages only). Separation of land masses caused by sea level changes during the Pliocene and Pleistocene may have been triggers for speciation in the Caribbean genus Spathelia.
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| 3. |
- Appelhans, M. S., et al.
(författare)
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Phylogeny, evolutionary trends and classification of the Spathelia-Ptaeroxylon clade : morphological and molecular insights
- 2011
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Ingår i: Annals of Botany. - : Oxford University Press (OUP). - 0305-7364 .- 1095-8290. ; 107:8, s. 1259-1277
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Tidskriftsartikel (refereegranskat)abstract
- Background and Aims The Spathelia-Ptaeroxylon clade is a group of morphologically diverse plants that have been classified together as a result of molecular phylogenetic studies. The clade is currently included in Rutaceae and recognized at a subfamilial level (Spathelioideae) despite the fact that most of its genera have traditionally been associated with other families and that there are no obvious morphological synapomorphies for the clade. The aim of the present study is to construct phylogenetic trees for the Spathelia-Ptaeroxylon clade and to investigate anatomical characters in order to decide whether it should be kept in Rutaceae or recognized at the familial level. Anatomical characters were plotted on a cladogram to help explain character evolution within the group. Moreover, phylogenetic relationships and generic limits within the clade are also addressed. Methods A species-level phylogenetic analysis of the Spathelia-Ptaeroxylon clade based on five plastid DNA regions (rbcL, atpB, trnL-trnF, rps16 and psbA-trnH) was conducted using Bayesian, maximum parsimony and maximum likelihood methods. Leaf and seed anatomical characters of all genera were (re) investigated by light and scanning electron microscopy. Key Results With the exception of Spathelia, all genera of the Spathelila-Ptaeroxylon clade are monophyletic. The typical leaf and seed anatomical characters of Rutaceae were found. Further, the presence of oil cells in the leaves provides a possible synapomorphy for the clade. Conclusions The Spathelia-Ptaeroxylon clade is well placed in Rutaceae and it is reasonable to unite the genera into one subfamily (Spathelioideae). We propose a new tribal classification of Spathelioideae. A narrow circumscription of Spathelia is established to make the genus monophyletic, and Sohnreyia is resurrected to accommodate the South American species of Spathelia. The most recent common ancestor of Spathelioideae probably had leaves with secretory cavities and oil cells, haplostemonous flowers with appendaged staminal filaments, and a tracheidal tegmen.
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| 4. |
- Bengtson, Annika, et al.
(författare)
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The Malagasy enigmatic genus Apodocephala (Asteraceae), a new member of the tribe Athroismeae
- 2021
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Ingår i: Willdenowia. - : Botanic Garden and Botanical Museum Berlin, Freie Universitaet Berlin. - 0511-9618 .- 1868-6397. ; 51:2, s. 221-230
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Tidskriftsartikel (refereegranskat)abstract
- Apodocephala is a small genus of nine species of shrubs and trees endemic to Madagascar and currently classified in the tribe Astereae (Asteraceae). However, its present tribal position has been questioned, as it lacks some of the salient morphological features of that tribe. This study includes for the first time DNA sequences from Apodocephala (two species including the type of the generic name) to test its phylogenetic position. Phylogenetic analyses based on sequence data from nuclear ribosomal (ETS and ITS) and plastid (ndhF and trnL–trnF) DNA regions, using Bayesian inference and maximum parsimony methods, strongly reject the placement of Apodocephala in the Astereae. Our results, instead, support its position as sister to the Malagasy monospecific genus Lowryanthus within the tribe Athroismeae. Morphological comparison of these sister genera reveal similarities in cypsela morphology, and the inclusion of Apodocephala in the subtribe Lowryanthinae is proposed here. The tribe Athroismeae is now represented by ten genera (Anisochaeta, Anisopappus, Apodocephala, Artemisiopsis, Athroisma, Blepharispermum, Centipeda, Leucoblepharis, Lowryanthus and Symphyllocarpus), six of which occur in Madagascar. The Malagasy Athroismeae occur in all Malagasy terrestrial ecosystems (rainforests, deciduous dry forests, thicket spiny forests and savannas) and are likely the result of multiple independent colonization events mostly from mainland Africa.
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| 5. |
- Borges, Rodrigo Lopes, et al.
(författare)
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Phylogeny of the Neotropical element of the Randia clade (Gardenieae, Rubiaceae, Gentianales)
- 2021
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Ingår i: Plant Ecology and Evolution. - : Agentschap Plantentuin Meise. - 2032-3913 .- 2032-3921. ; 154:3, s. 458-469
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Tidskriftsartikel (refereegranskat)abstract
- Background and aims – Generic limits of the tropical tribe Gardenieae (Ixoroideae, Rubiaceae) have partly remained unsettled. We produced a new phylogeny of the Randia clade, with emphasis on its Neotropical clade comprising five genera (Casasia, Randia, Rosenbergiodendron, Sphinctanthus, and Tocoyena). The result was subsequently used to evaluate and discuss: a) the respective monophyly of the above-mentioned genera and their interrelationships; b) relationships within Tocoyena and the evolutionary relevance of its subgeneric classification; and c) the monophyly of the morphologically variable T. formosa.Material and methods – We examined the phylogeny of the Randia clade based on maximum likelihood and Bayesian analyses of sequence data from two nuclear (ETS and Xdh) and two plastid (petB-petD and trnT-F) DNA regions from 59 individuals (including seven representatives from the remaining Ixoroideae).Key results – The Neotropical clade of the Randia clade comprises three major lineages, the Randia armata subclade, the Randia-Casasia subclade and the Rosenbergiodendron subclade. Neither Casasia nor Randia is monophyletic. Tocoyena is sister to Rosenbergiodendron + Sphinctanthus and is subdivided into three lineages: the Tocoyena pittieri group, the Tocoyena guianensis group, and the core Tocoyena. Tocoyena williamsii is paraphyletic with respect to T. pittieri. Tocoyena formosa is polyphyletic and should be re-circumscribed.Conclusions – Our results demonstrate the monophyly of each of the relatively species-poor genera Rosenbergiodendron, Sphinctanthus, and Tocoyena, and confirm their close affinity. The serial classification of Tocoyena does not reflect the evolutionary history of the genus. The paraphyly of T. williamsii with respect to T. pittieri, together with their morphological similarities and geographic distributions, support the inclusion of the former in the latter. Our study calls for additional phylogenetic work on Casasia and the more species-rich genus Randia. While the respective monophyly of both genera is rejected here, future work with a broader representation of Randia is needed.
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| 6. |
- 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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| 7. |
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| 8. |
- Davis, Aaron, et al.
(författare)
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Nomenclatural changes in the genus Bremeria (Rubiaceae)
- 2011
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Ingår i: Blumea - Journal of plant taxonomy and plant geography. - 0006-5196 .- 2212-1676. ; 56:1, s. 4-5
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Tidskriftsartikel (refereegranskat)abstract
- Five new combinations are made in the genus Bremeria: B. arachnocarpa, B. eriantha, B. scabrella, B. landia var. holosericea, and B. landia var. stadmanii. Bremeria gerrardii is conspecific with Gaertnera phanerophlebia, and thus excluded from Bremeria. Lectotypes are designated for Mussaenda erectiloba var. scabrella, M. stadmanii, and M. trichophlebia.
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| 9. |
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| 10. |
- De Block, Petra, et al.
(författare)
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Molecular phylogenetics and generic assessment in the tribe Pavetteae (Rubiaceae)
- 2015
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 64:1, s. 79-95
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Tidskriftsartikel (refereegranskat)abstract
- This is the first phylogenetic study focused on the Pavetteae, one of the most species-rich and morphologically diverse tribes within the coffee family (Rubiaceae). Fifteen of the 17 currently recognized genera, represented by 85 taxa, were sequenced for rps16, trnT-F and ITS and analysed using Bayesian inference and maximum likelihood methods. The monophyly of the Pavetteae is confirmed. Four major lineages are identified, but their phylogenetic relationships are not fully resolved. The continental African genera Rutidea, Nichallea and Tennantia, the Madagascan genera Homollea and Robbrechtia, and the paleotropical genus Pavetta are monophyletic. Other genera are paraphyletic in their current circumscriptions and the following changes are made: Homolliella is placed in synonymy with Paracephaelis, and Coleactina and Dictyandra with Leptactina, resulting in four new combinations. The large paleotropical genus Tarenna is shown not to be monophyletic. In the future, the name Tarenna should not be used for continental African species. Most of these could be transferred to the hitherto monospecific genus Cladoceras, but other species might constitute altogether new genera. The relationship between the monophyletic Asian-Pacific and Madagascan Tarenna species remains unclear. The phylogeny of the Madagascan genera of the Pavetteae is largely unresolved and the largest Madagascar-centred genus Coptosperma was not recovered as monophyletic. The low resolution for the Madagascan taxa can be considered as an indication of rapid radiation. Further molecular and morphological studies are necessary to clarify the phylogeny of the Pavetteae, especially regarding the African Tarenna species and the Madagascan genera of the tribe.
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| 11. |
- Ginter, Anna, et al.
(författare)
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Phylogenetic affinities of Myrioneuron and Cyanoneuron, generic limits of the tribe Argostemmateae and description of a new Asian tribe, Cyanoneuroneae (Rubiaceae)
- 2015
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 64:2, s. 286-298
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Tidskriftsartikel (refereegranskat)abstract
- Argostemmateae (Rubiaceae, subfam. Rubioideae) are a mostly tropical Asian group of about 200 species currently classified in four morphologically distinct genera (Argostemma, Mouretia, Mycetia, Neohymenopogon). The monophyly of the tribe and Mycetia is strongly supported by molecular data, however, the tropical Asian genus Myrioneuron, traditionally associated with Mycetia based on its berry fruits, has not previously been investigated. The Bornean and Sulawesian genus Cyanoneuron, described based on the species of Myrioneuron with drupaceous fruits, had not been sequenced. Therefore, the phylogenetic positions of Cyanoneuron and Myrioneuron within Rubiaceae and their generic status have yet to be assessed with molecular data. These genera have tentatively been placed in tribe Spermacoceae (Rubioideae). We reconstructed a robust phylogeny of Rubioideae with sequence data from five plastid regions of 176 accessions and using the Bayesian Markov chain Monte Carlo and parsimony methods. Once the positions of Cyanoneuron and Myrioneuron were revealed, a robust phylogeny of the Spermacoceae alliance was reconstructed with the combined plastid and nuclear data (nrETS, nrITS) from 61 accessions to reassess its tribal limits. Mycetia and Myrioneuron are non-monophyletic and intermixed, and formed a well-supported clade diagnosed by berry fruits. We formally transfer Myrioneuron to Mycetia (older name), and present nine new combinations in the latter genus. Cyanoneuron was resolved with high support as monophyletic, and appears to be closely related to the Chinese monogeneric tribes Foonchewieae and Dunnieae. A new tribe Cyanoneuroneae is described to accommodate Cyanoneuron. This tribe is morphologically distinct from related tribes by its stipules apically divided into multiple linear segments, condensed-cymose inflorescences and drupe-like fruits with numerous small seeds. A new key to the genera of Argostemmateae is provided.
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| 12. |
- Huang, Wei-Ping, et al.
(författare)
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Molecular phylogenetics and biogeography of the eastern Asian-eastern North American disjunct Mitchella and its close relative Damnacanthus (Rubiaceae, Mitchelleae)
- 2013
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Ingår i: Botanical journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4074 .- 1095-8339. ; 171:2, s. 395-412
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Forskningsöversikt (refereegranskat)abstract
- Mitchella is a small genus of the Rubiaceae with only two species. It is the only herbaceous semishrub of the family showing a disjunct distribution in eastern Asia and eastern North America, extending to Central America. Its phylogeny and biogeographical diversification remain poorly understood. In this study, we conducted phylogenetic and biogeographical analyses for Mitchella and its close relative Damnacanthus based on sequences of the nuclear internal transcribed spacer (ITS) and four plastid markers (rbcL, atpB-rbcL, rps16 and trnL-F). Mitchella is monophyletic, consisting of an eastern Asian M. undulata clade and a New World M. repens clade. Our results also support Michella as the closest relative to the eastern Asian Damnacanthus. The divergence time between the two intercontinental disjunct Mitchella species was dated to 7.73 Mya, with a 95% highest posterior density (HPD) of 3.14-12.53 Mya, using the Bayesian relaxed clock estimation. Ancestral area reconstructions suggest that the genus originated in eastern Asia. The semishrub Mitchella appears to have arisen from its woody ancestor in eastern Asia and then migrated to North America via the Bering land bridge in the late Miocene.
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| 13. |
- Kainulainen, Kent, et al.
(författare)
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Chapelieria magna, a new species of Rubiaceae from eastern Madagascar
- 2015
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Ingår i: PhytoKeys. - : Pensoft Publishers. - 1314-2011 .- 1314-2003. ; 44, s. 89-95
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Tidskriftsartikel (refereegranskat)abstract
- A new species of Chapelieria was discovered during a recent field trip to the Masoala National Park in eastern Madagascar, and is described here as Chapelieria magna Kainul., sp. nov. This species is readily distinguishable from previously described species of the genus by its quadrangular shoots, triangular-calyptrate stipules, sessile leaves, pubescent styles, and ridged fruits. It also differs in the larger number of ovules and the much larger size of leaves and fruits.
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| 14. |
- Kainulainen, Kent, et al.
(författare)
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Island hopping, long-distance dispersal and species radiation in the Western Indian Ocean : historical biogeography of the Coffeeae alliance (Rubiaceae)
- 2017
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 44:9, s. 1966-1979
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Tidskriftsartikel (refereegranskat)abstract
- Aim The Western Indian Ocean region (WIOR) is home to a very diverse and largely unique flora that has mainly originated via long-distance dispersals. The aim of this study is to gain insight into the origins of the WIOR biodiversity and to understand the dynamics of colonization events between the islands. We investigate spatial and temporal hypotheses of the routes of dispersal, and compare the dispersal patterns of plants of the Coffeeae alliance (Rubiaceae) and their dispersers. Rubiaceae is the second most species-rich plant family in Madagascar, and includes many endemic genera. The neighbouring archipelagos of the Comoros, Mascarenes and Seychelles also harbour several endemic Rubiaceae.Location The islands of the Western Indian Ocean.Methods Phylogenetic relationships and divergence times were reconstructed from plastid DNA data of an ingroup sample of 340 species, using Bayesian inference. Ancestral areas and range evolution history were inferred by a maximum likelihood method that takes topological uncertainty into account.Results At least 15 arrivals to Madagascar were inferred, the majority of which have taken place within the last 10 Myr. Most dispersal events were supported as being from mainland Africa, but Catunaregam may have dispersed from Asia. Although most Coffeeae alliance lineages are zoochorous, the general pattern of dispersals from Africa is incongruent with the biogeographic origins of the extant Malagasy volant frugivores. Several out-of-Madagascar dispersals were inferred to the neighbouring islands, as well as back-colonizations of Africa.Main conclusions The African flora has been of foremost importance as source of dispersal to the islands of the Western Indian Ocean. Following the colonization of Madagascar, rapid radiations appear to have taken place in some clades, and Madagascar has also been an important source area for subsequent dispersal to the Comoros, Mascarenes and Seychelles.
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| 15. |
- Kainulainen, Kent, et al.
(författare)
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Phylogenetic relationships and new tribal delimitations in subfamily Ixoroideae (Rubiaceae)
- 2013
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Ingår i: Botanical journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4074 .- 1095-8339. ; 173:3, s. 387-406
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Tidskriftsartikel (refereegranskat)abstract
- Subfamily Ixoroideae is one of three major lineages in Rubiaceae, with approximately 4000 species. Previous molecular phylogenetic studies have indicated that many genera and tribes previously placed in other subfamilies are better considered as part of Ixoroideae. However, the internal resolution and clade support have generally been low, and several genera found to be nested in the subfamily do not appear to be associated with any described tribe. In order to resolve the phylogeny and assess the tribal delimitations in the expanded Ixoroideae, phylogenetic reconstructions were performed using Bayesian and parsimony analyses of six plastid DNA regions and a broad sampling of genera from all tribes of the subfamily. In the inferred phylogenetic hypotheses, the tribal relationships were mostly well supported, with Ixoroideae consisting of the Coffeeae and the Vanguerieae alliances as sister groups and a grade comprising Condamineeae, Henriquezieae, Posoquerieae, Retiniphylleae, Sipaneeae and the genus Steenisia. A revised tribal classification, including the description of five new tribes, Airospermeae, Augusteae, Scyphiphoreae, Steenisieae and Trailliaedoxeae, is provided.
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| 16. |
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| 17. |
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| 18. |
- Krüger, Åsa, et al.
(författare)
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Molecular phylogeny of the tribe Danaideae (Rubiaceae: Rubioideae) : Another example of out-of-Madagascar dispersal
- 2012
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 61:3, s. 629-636
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Tidskriftsartikel (refereegranskat)abstract
- Extensive efforts have been made to resolve the phylogeny of the large coffee family (Rubiaceae) based on molecular data. As a result, several small tribes have been described, but the phylogenies and generic delimitations for many of these groups remain unclear. This study focuses on the small tribe Danaideae that belongs to subfamily Rubioideae and whose generic limits have not previously been addressed with molecular data. It is the sole rubiaceous tribe distributed almost entirely in the Western Indian Ocean region, with the exception of the East African Danais xanthorrhoea. The tribe consists of three genera: Danais, Payera (including the monotypic genus Coursiana), and Schismatoclada. We present the first molecular phylogenetic study of Danaideae including representatives from all three genera and using Bayesian and maximum parsimony methods and sequence data from nuclear DNA (nrITS) and chloroplast DNA (petD, psbA-trnH, rpl32-trnL(UAG), rps16). Our main objectives were to rigorously test the monophyly of Danaideae as currently circumscribed and assess phylogenetic relationships within the tribe. The findings of this study shed light on the colonization history of the tribe. Our analyses reaffirm the monophyly of Danaideae and Danais but reveal the paraphyly of Payera and Schismatoclada. The close relationship between the three Danaideae genera and Coursiana is supported. However, we found very little support for the inclusion of the latter genus in Payera as proposed earlier. The tribe is resolved in two morphologically distinct major lineages, the highly supported Damns clade with lianescent habit (= Danais sensu Buchner & Puff) and the Payera-Schismatoclada clade with arborescent habit. The Malagasy and Mauritian specimens of Danais fragrans are not closely related, and we restrict D. fragrans to the Mauritian taxa and resurrect Danais lyallii Baker to accommodate the Malagasy D. fragrans. According to our analysis. Madagascar is the origin of all species of Danaideae occurring in the Comoro archipelago, East Africa, and Mauritius. The Mauritian and East African Danais each is the result of a single colonization event, while there were at least two independent colonization events to the Comoros.
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| 19. |
- Löfstrand, Stefan D., et al.
(författare)
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Phylogeny and Generic Delimitations in the Sister Tribes Hymenodictyeae and Naucleeae (Rubiaceae)
- 2014
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Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 39:1, s. 304-315
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Tidskriftsartikel (refereegranskat)abstract
- The Hymenodicteae-Naudeeae clade is a predominantly Paleotropical group with 220 species in 28 genera. The phylogertetic relationships and generic limits within Naucleeae have previously been assessed using combined molecular-morphological data, however the status of some genera remains questionable. The evolutionary relationships within Hymenodictyeae have never been investigated before. We performed phylogenetic analyses of the Hymenodictyeae-Naucleeae clade using nuclear [nrETS; nrITS] and chloroplast [ndhF; rbcL; rps16; trnT-F] data and a large sampling of both tribes. Our study supports the monophyly of the tribes, all subtribes of Naucleeae (Adininae, Breoniinae, Cephalanthinae, Corynantheinae, Mitragyninae, Naucleinae, and Uncariinae), and the Hymenodictyeae genera Hymenodictyon and Paracorynanthe. In Naucleeae, the monotypic genera Adinauclea, Metadina, and Pertusadina are nested within Adina, Mitragyna within Fleroya, Ludekia, Myrmeconauclea, and Ochreinauclea within Neonauclea, and Burttdavya and Sarcocephalus within Nauclea. Corynanthe and Pausinystalia are mutually paraphyletic. We provisionally maintain the current generic status of Neonauclea and its allied genera, pending further study. In sum, we recognize 17 genera in Naucleeae: Adina s. l., Breonadia, Breonia, Cephalanthus, Corynanthe s. l., Diyaminauclea, Gyrostipula, Janotia, Khasiaclunea, Ludekia, Mitragyna s. l., Myrmeconauclea, Nauclea s. l., Neolamarckia, Neonauclea, Ochreinauclea, and Uncaria. Five new combinations were made: Adina euryncha, Adina malaccensis, Corynanthe lane-poolei subsp. iturense, Corynanthe talbotii, and Nauclea nyasica.
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| 20. |
- Mouly, Arnaud, et al.
(författare)
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Phylogenetic structure and clade circumscriptions in the Gardenieae complex (Rubiaceae)
- 2014
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 63:4, s. 801-818
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Tidskriftsartikel (refereegranskat)abstract
- In this study we investigate the large and diverse Rubiaceae-Gardenieae and closely related tribes Bertiereae, Coffeeae, Cremasporeae, Octotropideae, and Pavetteae. Some of the tribes or groups have been shown to be monophyletic and strongly supported, but the phylogeny of this large complex is still far from being satisfactorily elucidated particularly for Gardenieae, both in terms of intertribal relationships as well as tribal delimitations. We reconstruct the phylogeny of the complex using an extensive sampling of 108 genera and five plastid DNA regions. Phylogenetic relationships demonstrate that Gardenieae sensu Andreasen & Bremer is polyphyletic, as Burchellia, Didymosalpinx, Monosalpinx, and Mantalania are closer to Octotropideae-Cremasporeae. In addition, Pavetteae and the investigated members of Aulacocalyceae are nested in a supported but partially unresolved Gardenieae-Pavetteae clade. Within this clade, several strongly supported groups are resolved: an Aidia group, an Alibertia group, a Gardenia group, Pavetteae including Pelagodendron, a Porterandia group, a Randia group, a Rothmannia group (including Aulacocalyx and Heinsenia), a Sherbournia group, and the two isolated genera Massularia and Schumanniophyton. The latter genus presented a high rate of genetic substitutions, which resulted in perturbations of the phylogenetic reconstruction. A revised tribal circumscription is given for Gardenieae, the Alibertia group is recognized at tribal level as an emended Cordiereae, and a new tribe, Sherbournieae, is described to accommodate the members of the Sherbournia group.
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| 21. |
- Rakotoarivelo, Fanny P., et al.
(författare)
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Molecular systematics and evolutionary trends and relationships in the genus Jumellea (Orchidaceae) : Implications for its species limits
- 2012
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 61:3, s. 534-544
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Tidskriftsartikel (refereegranskat)abstract
- Jumellea is an orchid genus centered on Madagascar but also occurs on some of the neighboring oceanic islands (the Mascarenes and Comoros) and in southern and eastern Africa. Prior to our study the genus contained ca. 55 morphologically distinct species, of which six are found in the Comoros (three endemic, three shared with Madagascar), nine in the Mascarenes (four endemic, four shared with Madagascar), two in southern and eastern Africa (both endemic), and 41 species endemic to Madagascar. We perform Bayesian and parsimony phylogenetic analyses of Jumellea based on combined chloroplast (matK, trnL-F, rps16, ycf1) and nuclear (nrITS) data from 60 specimens representing 47 species, four subspecies, and two varieties of Jumellea: (1) to assess the phylogenetic value of growth form, leaf, bract and lip shape, and spur length, presently used for recognizing informal groups within the genus; and (2) to test the monophyly of some variable species (e.g., J. gracilipes, J. lignosa). We find no support for the informal groups of Jumellea, as all the characters tested are evolutionarily labile. Jumellea lignosa (comprising J. lignosa subsp. lignosa, subsp. tenuibracteata, subsp. actuissima, and subsp. latilabia) is not monophyletic unless subsp. tenuibracteata is excluded. Jumellea gracilipes s.l. (including J. ambongensis, J. imerinensis, and J. unguicularis) is polyphyletic. As a result, we resurrect these three latter species, and recognize J. lignosa subsp. tenuibracteata at species level. Furthermore, we propose new circumscriptions for the following species: the Comorian J. arachnantha (including the Malagasy J. sagittata); the Reunionese J. exilis (including the Malagasy J. flavescens); the Reunionese J. recta (including the Malagasy Jumellea sp. I); the Reunionese J. recurva (including the Malagasy J. pandurata); and the Reunionese J. stenophylla (including the Malagasy J. gracilipes 2 and 3). Finally, Jumellea arborescens and J. maxillarioides are recorded from Madagascar and the Comoros. Finally, the number of species of Jumellea has now increased from 55 to 57: seven species in the Comoros (four shared with Madagascar), nine species in the Mascarenes (four shared with Madagascar), two species in Africa, and 39 species, three subspecies, and two varieties restricted to Madagascar.
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| 22. |
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| 23. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Evolution and trends in the Psychotrieae alliance (Rubiaceae) - A rarely reported evolutionary change of many-seeded carpels from one-seeded carpels
- 2008
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 48:1, s. 207-223
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Tidskriftsartikel (refereegranskat)abstract
- Bayesian and parsimony analyses of five plastid gene and nrITS regions from 58 Rubioideae (Rubiaceae) taxa further support the sister-group relationship between the African monotypic genus Schizocolea and the Psychotrieae alliance sensu Bremer & Manen. Our analyses show that the Psychotrieae alliance can be subdivided into in four well-supported clades: Schizocolea, (Schradereae(Gaertnereae(Mitchelleae–Morindeae s.s.))), Palicoureeae–Psychotrieae s.s., and Craterispermeae–Prismatomerideae. The relationships between the latter three clades remain unsettled. Our study further reveals much higher numbers of molecular autapomorphies of the tribes compared with those of molecular synapomorphies of two sister tribes or groups of tribes. Within the newly delimited Psychotrieae alliance a one-seeded carpelwas inferred as ancestral and many- and two-seeded carpels evolved once each. We describe Mitchelleae to accommodate Damnacanthus and Mitchella and restrict Morindeae to include only Appunia, Coelospermum, Gynochthodes, Morinda, Pogonolobus, and Syphonandrium. Mitchelleae is characterized e.g., by placentae inserted near the top of the septum and a single campylotropous ovule per carpel, while Morindeae s.s. has massive and T-shaped placentae inserted in the middle of the septum and two anatropous ovules per carpel.
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| 24. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Evolution of Growth Habit, Inflorescence Architecture, Flower Size, and Fruit Type in Rubiaceae : Its Ecological and Evolutionary Implications
- 2012
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:7, s. e40851-
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Tidskriftsartikel (refereegranskat)abstract
- During angiosperm evolution, innovations in vegetative and reproductive organs have resulted in tremendous morphological diversity, which has played a crucial role in the ecological success of flowering plants. Morindeae (Rubiaceae) display considerable diversity in growth form, inflorescence architecture, flower size, and fruit type. Lianescent habit, head inflorescence, small flower, and multiple fruit are the predominant states, but arborescent habit, non-headed inflorescence, large flower, and simple fruit states occur in various genera. This makes Morindeae an ideal model for exploring the evolutionary appearances and transitions between the states of these characters. We reconstructed ancestral states for these four traits using a Bayesian approach and combined nuclear/chloroplast data for 61 Morindeae species. The aim was to test three hypotheses: 1) self-supporting habit is generally ancestral in clades comprising both lianescent and arborescent species; 2) changes from lianescent to arborescent habit are uncommon due to "a high degree of specialization and developmental burden''; 3) head inflorescences and multiple fruits in Morindeae evolved from non-headed inflorescences and simple fruits, respectively. Lianescent habit, head inflorescence, large flower, and multiple fruit are inferred for Morindeae, making arborescent habit, non-headed inflorescence, small flower, and simple fruit derived within the tribe. The rate of change from lianescent to arborescent habit is much higher than the reverse change. Therefore, evolutionary changes between lianescent and arborescent forms can be reversible, and their frequency and trends vary between groups. Moreover, these changes are partly attributed to a scarcity of host trees for climbing plants in more open habitats. Changes from large to small flowers might have been driven by shifts to pollinators with progressively shorter proboscis, which are associated with shifts in breeding systems towards dioecy. A single origin of dioecy from hermaphroditism is supported.
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| 25. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Evolutionary trends, major lineages, and new generic limits in the dioecious group of the tribe vanguerieae (rubiaceae) : Insights into the evolution of functional dioecy
- 2009
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Ingår i: Annals of the Missouri Botanical Garden. - : Missouri Botanical Garden Press. - 0026-6493 .- 2162-4372. ; 96, s. 161-181
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Tidskriftsartikel (refereegranskat)abstract
- New generic circumscriptions of the Paleotropical tribe Vanguerieae in the subfamily Ixoroideae s.l. (Rubiaceae) have recently been established its a result of it series of phylogenetic studies conducted by Lantz and Bremer. The genus Canthium Lam. was shown in their study to be highly polyphyletic, and a largely dioecious group was for the first little identified within Vanguerieae. dioecious group sensu Lantz and Bremer comprises about 140 species classified in eight genera: Canthium (Canthium subg. Bullockia Bridson), Dinocanthium Bremek., Leroya Cavaco, Neoleroya Cavaco, Peponidium (Baill.) Arenes, Pseudopeponidium Homolles ex Arenes, Pyrostria Comm. ex Juss., and Scyphochlamys Balf. f. We sequenced 79 Vanguerieae taxa and performed phylogenetic analyses based on sequence data from two nuclear (EN and ITS) markers to: (1) pinpoint the phylogenetic positions of the Comorean and Indian Ocean Canthium and the Southeast Asian Canthium confertum Korth. group in Vanguerieae; (2) evaluate the phylogenetic utility of three taxonomic characters (bract type, locule number, and fruit shape) previously and currently used for delimiting genera in the dioecious group; and (3) assess the evolution of functional dioecy in Vanguerieae. The results support it further disintegration of Canthium s.l., as the Comorean and Malagasy Canthium species are shown for the first time to be closely related to Peponidium. Similarly, C. confertum appears to have a close affinity with Cyclophyllum Hook. f. The combined analyses show that [lie dioecious group call he subdivide(] into four morphologically distinct clades formally recognized as genera: Bullockia (Bridson) Razafim., Lantz & B. Bremer, here elevated from Canthium subgen. Bullockia Bridson, Lis well its Cyclophyllum, Peponidium (including all Comorean, Malagasy, and Seychellean Canthium species), and Pyrostria (including Dinocanthium, Leroya, Neoleroya., Pseudopeponidium, and Scyphochlamys). All described species of Canthium subgen. Bullockia are transferred to Bullockia: B. dryscriton (Bullock) Razafim., Lantz & B. Bremer, B.fadenii (Bridson) Razafim., Lantz & B. Bremer, B. impressinervia (Bridson) Razafim., Lantz & B. Bremer, B. mombazensis (Baill.) Razafim., Lantz & B. Bremer, B. pseudosetiflora (Bridson) Razafim., Lantz & B. Bremer, and B. setiflora (Hiern) Razafim., Lantz & B. Bremer. Furthermore, the results seem to point to a single origin of functional dioecy followed by subsequent reversals [lack to tire hermaphroditic conditions at least within the Cyclophyllum-Canthium confertum clade and Pyrostria s.l. The Malagasy Bullockia species seem to have an African ancestor, whereas the Comorean Peponidium and the African Pyrostria appear to have originated from Malagasy progenitors.
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| 26. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Implications of a molecular phylogenetic study of the Malagasy genus Cedrelopsis and its relatives (Ptaeroxylaceae)
- 2010
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 57:1, s. 258-265
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Tidskriftsartikel (refereegranskat)abstract
- Ptaeroxylaceae is an Afro-Malagasy family containing three genera, Bottegoa. Cedrelopsis, and Ptaeroxylon. Although the family is morphologically well delimited, it is currently considered part of the subfamily Spathelioideae in a broadly circumscribed orange family (Rutaceae). The Malagasy Cedrelopsis has traditionally been associated with different families of the order Sapindales and its phylogenetic placement in Rutaceae sensu lato has yet to be tested with molecular data. The present molecular phylogenetic study reaffirms the monophyly of Ptaeroxylaceae and its placement in Spathelioideae. Therefore, molecules and morphology support close affinities between Bottegoa, Cedrelopsis, and Ptaeroxylon and also their current generic circumscriptions. We report a case of an evolutionary change from one-seeded to two-seeded carpels within the Harrisonia-Cneorum-Ptaeroxylaceae clade of Spathelioideae. Finally, the sister-group relationship between the African Bottegoa and the Afro-Malagasy Ptaeroxylon-Cedrelopsis clade suggests an African origin of Cedrelopsis.
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| 27. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Molecular support for a basal grade of morphologically distinct, monotypic genera in the species-rich Vanguerieae alliance (Rubiaceae, Ixoroideae) : Its systematic and conservation implications
- 2011
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Ingår i: Taxon. - 0040-0262 .- 1996-8175. ; 60:4, s. 941-952
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Tidskriftsartikel (refereegranskat)abstract
- Many monotypic genera with unique apomorphic characters have been difficult to place in the morphology-based classifications of the coffee family (Rubiaceae). We rigorously assessed the subfamilial phylogenetic position and generic status of three enigmatic genera, the Seychellois Glionnetia, the Southeast Asian Jackiopsis, and the Chinese Trailliaedoxa within Rubiaceae, using sequence data of four plastid markers (ndhF, rbcL, rps16, trnT-F). The present study provides molecular phylogenetic support for positions of these genera in the subfamily Ixoroideae, and reveals the presence of a basal grade of morphologically distinct, monotypic genera (Crossopteryx,Jackiopsis,Scyphiphora,Trailliaedoxa, and Glionnetia, respectively) in the species-rich Vanguerieae alliance. These five genera may represent sole representatives of their respective lineages and therefore may carry unique genetic information. Their conservation status was assessed, applying the criteria set in IUCN Red List Categories. We consider Glionnetia and Jackiopsis Endangered. Scyphiphora is recognized as Near Threatened despite its extensive range and Crossopteryx as Least Concern. Trailliaedoxa is poorly known (Data Deficient). Finally, the generic status of Glionnetia,Jackiopsis, and Trailliaedoxa and the monogeneric tribe Jackieae as defined by Ridsdale are supported.
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| 28. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Nomenclatural changes and taxonomic notes in the tribe Morindeae (Rubiaceae)
- 2011
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Ingår i: Adansonia. - : Museum National d'Histoire Naturelle, Paris, France. - 1280-8571 .- 1639-4798. ; 33:2, s. 283-309
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Tidskriftsartikel (refereegranskat)abstract
- A new circumscription and new generic delimitations of the tribe Morindeae in the subfamily Rubioideae (Rubiaceae) have been proposed as a result of two recent molecular phylogenetic studies. The adoption of a narrow circumscription of Morinda and a broad circumscription of Gynochthodes requires new combinations and names in these genera. This study presents descriptions of the newly delimited Gynochthodes and Morinda, and 78 new combinations (73 in the former and five in the latter) and three new names (Gynochthodes alejandroi Razafim. & B.Bremer, G. ridsdalei Razafim. & B.Bremer, and G. wongii Razafim. & B.Bremer). We make three lectotypifications, and recognize 15 species in Appunia, 11 species in Coelospermum, 93 species in Gynochthodes, 39 species in Morinda, and one species in Siphonandrium. Finally, a list of all currently recognized species for each genus of Morindeae is presented.
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| 29. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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Origin of the pantropical and nutriceutical Morinda citrifolia L. (Rubiaceae) : comments on its distribution range and circumscription
- 2010
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:3, s. 520-529
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Tidskriftsartikel (refereegranskat)abstract
- Aim Morinda citrifolia L., commercially known as noni or the Indian mulberry plant, is morphologically variable and the only widely distributed member of the pantropical genus Morinda sensu stricto (Rubiaceae). This large distribution has been attributed partly to the ability of the seeds of the large-fruited M. citrifolia L. var. citrifolia L. to be transported by oceanic drifting. This form of M. citrifolia var. citrifolia has been predicted to be the progenitor colonizer of the island endemic Morinda species. Using a phylogenetic approach and large sampling of the widespread, large-fruited M. citrifolia var. citrifolia, we assessed the potential area of origin of M. citrifolia and tested the hypothesis that the large-fruited M. citrifolia var. citrifolia is an ancestral colonizer. Location Tropics. Methods We performed Bayesian analyses of 22 species of the tribe Morindeae (including 11 individuals of the three currently recognized varieties of M. citrifolia) based on combined nrETS, nrITS, rps16 and trnT-F sequence data. Geographic origins of the studied taxa were mapped onto the Bayesian majority rule consensus tree. Results Nine sequenced individuals of M. citrifolia from diverse geographic locations formed a highly supported clade, which was sister to the Australo-Micronesian clade that included M. bracteata var. celebica and M. latibracteata. These sister clades are part of the broader Asian, arborescent Morinda clade. We found no support for the current varietal classification of M. citrifolia. Main conclusions Our analyses suggest a Micronesian origin of M. citrifolia. This implies that the large-fruited M. citrifolia var. citrifolia might well have been present in the Pacific before the arrival of the Micronesian and Polynesian ancestors from Southeast Asia. The wide distribution of this form of M. citrifolia var. citrifolia is attributed partly to the trans-oceanic dispersal of its buoyant seeds, self-pollination and its ability to produce flowers and fruits year-round. The hypothesis that the widespread, large-fruited M. citrifolia var. citrifolia is the progenitor colonizer of the island endemic Morinda species is inconsistent with its derived position within the Asian, arborescent Morinda clade and with the fact that the nine sampled individuals of M. citrifolia form a clade.
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| 30. |
- Razafimandimbison, Sylvain G., et al.
(författare)
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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
- 2014
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Ingår i: American Journal of Botany. - : Wiley. - 0002-9122 .- 1537-2197. ; 101:7, s. 1102-1126
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Tidskriftsartikel (refereegranskat)abstract
- 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 leafnodulated 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.
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| 31. |
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| 32. |
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| 33. |
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| 34. |
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| 35. |
- Smedmark, Jenny E. E., et al.
(författare)
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A Phylogeny of Urophylleae (Rubiaceae) based on rps16 intron data
- 2008
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Ingår i: Taxon. - 0040-0262. ; 57:1, s. 24-32
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Tidskriftsartikel (refereegranskat)abstract
- This is the first study of phylogenetic relationships within the pantropical group Urophylleae. Previous studies have included few representatives from this group and little is known about its phylogeny. Here we use sequence data from the rps16 intron to address the question of where the four genera Temnopteryx, Pentaloncha, Pleiocarpidia, and Poecilocalyx, which have sometimes been classified in this group belong. By using different outgroups we show that there is conflict regarding the resolution among lineages in Rubioideae, which partly affects the support for relationships within Urophylleae. Urophylleae is shown to consist of two sister groups, one larger consisting only of Old World taxa and one smaller including the New World genera Amphidasya and Raritebe, and as sister of these two groups the African monotypic genus Temnopteryx. Pentaloncha, Pleiocarpidia, and Poecilocalyx all belong in the large Old World clade, which only comprises taxa included in the original circumscription of Urophylleae. Relationships within this group are not completely resolved, but Poecilocalyx is found to be the sister of Stelechantha and Pleiocarpidia to be the sister of Urophyllum leucophleum. Urophyllum is paraphyletic, as it seems to include Maschalocorymbus, Pleiocarpidia, Praravinia, and Pravinaria. It is not clear from the present analysis whether Pauridiantha is monophyletic or not.
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| 36. |
- Smedmark, Jenny E. E., et al.
(författare)
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Inferring geographic range evolution of a pantropical tribe in the coffee family (Lasiantheae, Rubiaceae) in the face of topological uncertainty
- 2014
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 70, s. 182-194
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Tidskriftsartikel (refereegranskat)abstract
- In this study we explore what historical biogeographic events are responsible for the wide and disjunct distribution of extant species in Lasiantheae, a pantropical group of trees and shrubs in the coffee family. Three of the genera in the group, Lasianthus, Saldinia, and Trichostachys, are found to be monophyletic, while there are indications that the fourth, Ronabea, is paraphyletic. We also address how the uncertainty in topology and divergence times affects the level of confidence in the biogeographic reconstruction. A data set consisting of chloroplast and nuclear ribosomal DNA data was analyzed using a Bayesian relaxed molecular clock approach to estimate phylogenetic relationships and divergence times, and the dispersal-extinction-cladogenesis (DEC) method to reconstruct geographic range evolution. Our results show that the Lasiantheae stem lineage originated in the neotropics, and the group expanded its range to the palaeotropics during the Eocene, either by continental migration through the boreotropics or by transatlantic long-distance dispersal. Two cases of Oligocene/Miocene over water-dispersal were also inferred, once from the paleotropics to the neotropics within Lasianthus, and once to Madagascar, concurrent with the origin of Saldinia. A lot of the diversification within Lasianthus took place during the Miocene and may have been influenced by climatic factors such as a period of markedly warm and moist climate in Asia and the aridification of the interior of the African continent. When biogeographic reconstructions were averaged over a random sample of 1000 dated phylogenies, the confidence in the biogeographic reconstruction decreased for most nodes, compared to when a single topology was used. A good understanding of phylogenetic relationships is necessary to understand the biogeographic history of a group, bit since the phylogeny is rarely completely known it is important to include phylogenetic uncertainty in biogeographic analysis. For nodes where the resolution is uncertain, the use of a single best topology as a basis for biogeographic analysis will result in inflated confidence in a biogeographic reconstruction which may be just one of several possible reconstructions.
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| 37. |
- Taylor, Charlotte, et al.
(författare)
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Eumachia expanded, a tropical genus distinct from Psychotria (Rubiaceae, Palicoureeae)
- 2017
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Ingår i: Candollea. - : Society of Conservatoire at Jardin Botaniques de la Ville de Geneve. - 0373-2967 .- 2235-3658. ; 72, s. 289-318
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Tidskriftsartikel (refereegranskat)abstract
- The pantropical genus Margaritopsis C. Wright (Rubiaceae, Palicoureeae) was recently separated from Psychotria L. and transferred to a different tribe, Palicoureeae, based on both molecular and morphological data. Margaritopsis has been studied in the Neotropics, and in Africa as Chazaliella E.M.A. Petit & Verdc. ; the species that belong to this group in the Pacific are enumerated for the first time here. Recently Eumachia DC. was found to be an older name for this group, and a few species of Margaritopsis have been transferred nomenclaturally to that genus. Here Eumachia is surveyed comprehensively for the first time, with a list of species and an overview of morphological characteristics. The remaining species of Margaritopsis are nomenclaturally transferred here to Eumachia, along with one species of Hodgkinsonia F. Müll., one species of Mapouria Aubl., and several species of Psychotria from Asia, Australia, New Guinea, and the Pacific region. In this new circumscription Eumachia includes 83 species, and is characterized within Palicoureeae by a yellowish green drying color ; stipules that are persistent or fall by fragmentation and are generally glandular when young and hardened when old ; green to whitened inflorescence axes ; white to cream or yellowish green, often rather small corollas ; orange to red fruits ; pyrenes with marginal pre-formed germination slits and no ethanol-soluble pigments ; and non-ruminate endosperm. Eumachia includes 20 species, 8 subspecies, and 7 varieties in Africa, 27 species in the Neotropics, and 36 species and 6 varieties in Asia, Australasia, and the Pacific region. Here we publish 81 new nomenclatural combinations in Eumachia and two new synonymies for Neotropical names, and 11 names from various regions are lectotypified.
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| 38. |
- Thulin, Mats, 1948-, et al.
(författare)
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Ambilobea, a new genus from Madagascar, the position of Aucoumea, and comments on the tribal classification of the frankincense and myrrh family (Burseraceae)
- 2008
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Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 26:04-mar, s. 218-229
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Tidskriftsartikel (refereegranskat)abstract
- Phylogenetic analyses of 46 species, representing all tribes and 14 out of 18 recognized genera of Burseraceae, are performed using nuclear ETS and plastid rps16 sequences. Boswellia madagascariensis, the only Malagasy species of this genus, is shown to belong to a clade comprising all sampled members of the current tribe Canarieae plus Triomma, whereas other species of Boswellia (including the type, B. serrata) form a clade that is strongly supported as sister to Garuga. A new genus, Ambilobea, is proposed for B. madagascariensis and the new combination A. madagascariensis is made. Ambilobea differs from Boswellia s. s. by being dioecious and by having valvate petals and, furthermore, is unique in the family by its winged tips to the petioles, by having pyrenes that remain attached to the detached valves of the fruit at dehiscence, and by its long-spinose pollen grains. Aucoumea, a monotypic central African rain forest genus, is strongly supported as sister to a clade with the arid-adapted Bursera and Commiphora. Boswellia s. s. and Garuga form a clade characterized by having hermaphroditic flowers. The relationships within Burseraceae emerging from this and previous phylogenetic studies are, on several points, in conflict with current tribal delimitation. The following suggestions for a new tribal classification of Burseraceae are made: 1) Beiselia, sister to the rest of the family, needs to be placed in a tribe of its own, Beiselieae, trib. nov., 2) Protieae should be restricted to Crepidospermum, Protium and Tetragastris, although generic rearrangements seem to be needed within this tribe, 3) Bursereae should be restricted to Aucoumea, Bursera and Commiphora, but generic rearrangements are needed in the Bursera-Commiphora complex, 4) the remaining genera, Ambilobea, Boswellia, Canarium, Dacryodes, Garuga, Haplolobus, Pseudodacryodes, Rosselia, Santiria, Scutinanthe, Trattinnickia and Triomma, are probably best placed in a broadly circumscribed Garugeae.
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| 39. |
- Thulin, Mats, et al.
(författare)
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Phylogeny of the Turneraceae clade (Passifloraceae s.l.) : Trans-Atlantic disjunctions and two new genera in Africa
- 2012
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Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 61:2, s. 308-323
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Tidskriftsartikel (refereegranskat)abstract
- Turneraceae, with just over 200 species in 10 genera, is today often included in a widely circumscribed Passifloraceae. The vast majority of the species are found in the New World, whereas generic diversity is largest in the Old World. According to current circumscriptions, three of the genera show trans-Atlantic disjunctions: Turnera with over 135 species in America and two species in Africa (one in the south-western and one in the north-eastern part), Piriqueta with 44 species in America and one in southern Africa, and Erblichia with one species in Central America and four in Madagascar. The phylogeny of Turneraceae is reconstructed based on DNA sequences from plastid trnL-F and nuclear ITS and sampling for all genera, including both New and Old World species for the trans-Atlantic groups to test their monophyly. The genera of Turneraceae form a strongly supported monophyletic group, the Turneraceae clade, within Passifloraceae s.l. The phylogeny is geographically structured, with one clade comprising American species only, except for the two African species of Turnera, and another clade with all other African species plus the Central American Erblichia odorata. Turnera is retrieved as monophyletic with the two African species appearing as close relatives of T. ulmifolia, the type of Turnera. The existence of a trans-Atlantic disjunction in Turnera is therefore supported. It is most likely caused by long-distance dispersal and estimated to be not older than late Miocene. In Piriqueta only the American species are supported as a monophyletic group, whereas the single African species is resolved as a member of the African clade. The trans-Atlantic disjunction in Piriqueta is therefore not supported and the African species is proposed to be placed in a genus of its own, Afroqueta gen. nov., as Afroqueta capensis comb. nov. Erblichia on Madagascar is supported as sister to Mathurina, a genus endemic to Rodrigues Island in the Mascarenes, and does not group with E. odorata in Central America, the type of Erblichia. The trans-Atlantic disjunction in Erblichia is therefore not supported either and the genus Arboa gen. nov. is proposed to accommodate the four Malagasy species, Arboa integrifolia comb. nov., Arboa berneriana comb. nov., Arboa madagascariensis comb. nov., and Arboa antsingyae comb. nov.
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| 40. |
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| 41. |
- Thureborn, Olle, 1984-
(författare)
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Phylogeny and topological incongruence in the Rubioideae (Rubiaceae)
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The work with this thesis has focused on evolutionary relationships in the Rubioideae, the most species-rich subfamily of the large and diverse coffee family (Rubiaceae). Despite considerable efforts during the last decades, uncertainty regarding several relationships in this group has remained, either as a result of unconvincing statistic support, incongruent results, or insufficient taxon sampling. Here, sequence data were obtained using both traditional and recently developed molecular methods, substantially expanding the amount of sequence data available for phylogenetic analysis within Rubioideae. Leveraging considerable amounts of data from a comprehensive sample of taxa showed to be highly effective in resolving phylogenetic relationships in the group, including its most recalcitrant parts. The results indicated that nuclear gene tree discordance at short internodes were frequently consistent with high levels of incomplete lineage sorting (ILS) owing to rapid diversification in the group. This finding may explain why some relationships have been notoriously difficult to resolve. Furthermore, while the results from coalescent simulations indicated that ILS alone can explain most of the observed cytonuclear incongruence, plastome introgression may be the more likely explanation in at least one case. Within Rubioideae the tribe Anthospermeae was studied in more detail. The phylogenetic analyses of this tribe revealed several cases and types of topological incongruence. Nevertheless, the deepest splits of the Anthospermeae phylogeny were congruent among analyses, but partly inconsistent with the traditional subtribal delimitation of the tribe. The infratribal classification of Anthospermeae was therefore partly updated. Unusual plastome features were also found within Anthospermeae, comprising large inversions and (putative) mitochondrial-to-plastome DNA transfer. With few other exceptions, plastomes across the Rubioideae tend to be highly conserved and typically conform to the canonical structure, gene content, and gene order of the majority of flowering plants.
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| 42. |
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| 43. |
- Wikström, Niklas, et al.
(författare)
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A Revised Time Tree of the Asterids : Establishing a Temporal Framework For Evolutionary Studies of the Coffee Family (Rubiaceae)
- 2015
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:5
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Tidskriftsartikel (refereegranskat)abstract
- Divergence time analyses in the coffee family (Rubiaceae) have all relied on the same Gentianales crown group age estimate, reported by an earlier analysis of the asterids, for defining the upper age bound of the root node in their analyses. However, not only did the asterid analysis suffer from several analytical shortcomings, but the estimate itself has been used in highly inconsistent ways in these Rubiaceae analyses. Based on the original data, we here reanalyze the divergence times of the asterids using relaxed-clock models and 14 fossil-based minimum age constraints. We also expand the data set to include an additional 67 taxa from Rubiaceae sampled across all three subfamilies recognized in the family. Three analyses are conducted: a separate analysis of the asterids, which completely mirrors the original asterid analysis in terms of taxon sample and data; a separate analysis of the Gentianales, where the result from the first analysis is used for defining a secondary root calibration point; and a combined analysis where all taxa are analyzed simultaneously. Results are presented in the form of a time-calibrated phylogeny, and age estimates for asterid groups, Gentianales, and major groups of Rubiaceae are compared and discussed in relation to previously published estimates. Our updated age estimates for major groups of Rubiaceae provide a significant step forward towards the long term goal of establishing a robust temporal framework for the divergence of this biologically diverse and fascinating group of plants.
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| 44. |
- Xie, Peiwu, et al.
(författare)
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Phylogenetic position of Guihaiothamnus (Rubiaceae) : Its evolutionary and ecological implications
- 2014
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 78, s. 375-385
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Tidskriftsartikel (refereegranskat)abstract
- Guihaiothamnus (Rubiaceae) is an enigmatic, monotypic genus endemic to southwestern China. Its generic status has never been doubted because it is morphologically unique by having rosette habit, showy, long-corolla-tubed flowers, and multi-seeded indehiscent berry-like fruits. The genus has been postulated to be a relict in the broad-leaved forests of China, and to be related to the genus Wendlandia, which was placed in the subfamily Cinchonoideae and recently classified in the tribe Augusteae of the subfamily Dialypetalanthoideae. Using combined evidence from palynology, cytology, and DNA sequences of nuclear ITS and four plastid markers (rps16, trnT-F, ndhF, rbcL), we assessed the phylogenetic position of Guihaiothamnus in Rubiaceae. Our molecular phylogenetic analyses placed the genus deeply nested within Wendlandia. This relationship is corroborated by evidence from palynology and cytology. Using a relaxed molecular clock method based on five fossil records, we dated the stem age of Wendlandia to be 17.46 my and, the split between G. acaulis and related Wendlandia species in southwestern China to be 2.11 mya. This young age, coupled with the derived position in Wendlandia, suggests an evolutionary derivation rather than an evolutionary relict of G. acaulis. Its rosette habit and large showy flowers, which are very distinctive from other Wendlandias, are interpreted as a result of recent rapid adaptation to rock and cliff habitats.
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