In the course of a taxonomic revision of the genus Pyrostria Comm. ex Juss. (Rubiaceae, Vanguerieae) in Madagascar, we describe five new species endemic from the Island: Pyrostria ambohitantelensis Atalahy, Rakotonas. & Razafim., Pyrostria ambrensis Atalahy, Rakotonas. & Razafim., Pyrostria betsomangensis Atalahy, Rakotonas. & Razafim., Pyrostria coriacea Atalahy, Rakotonas. & Razafim. and Pyrostria longicorollata Atalahy, Rakotonas. & Razafim. Each new species is provided with line drawings, a discussion on its morphological affinities and a risk of extinction assessment based on the IUCN Red List criteria.

A variety of the Malagasy genus Canthium Lam. (Rubiaceae, Vanguerieae), Canthium perrieri var. louvelii Cavaco, is transferred to the genus Pyrostria Comm. ex Juss. because, like the typical variety already transferred in this genus, it shares its distinctive characters (inflorescences or solitary flowers involucrate). This taxon is further raised to species level, as it is morphologically distinct from Pyrostria perrieri (Cavaco) Razafim. et al. We provide the necessary new replacement name: Pyrostria orientalis A. Atalahy, Rakotanas. & Razafim., since the epithet louvelii is already occupied in Pyrostria.

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.

The Astereae subtribe Madagasterinae (Asteraceae) sensu Nesom encompassing four Malagasy genera (Apodocephala, Madagaster, Rochonia and Vernoniopsis) is polyphyletic, as Apodocephala is a member of the Malagasy subtribe Lowryanthina of the tribe Athroismeae. While Madagaster was shown to belong to Astereae, the phylogenetic positions of Rochonia and Vernoniopsis (now Jalantzia) in this tribe remained to be tested with molecular data. Lowryanthinae presently contains Apodocephala with nine species and the monospecific Lowryanthus. The monophyly of Apodocephala remained to be assessed using a comprehensive sampling. The aims were to: (1) assess the phylogenetic placements of Rochonia and Jalantzia (Vernoniopsis) and test the monophyly of Jalantzia; (2) assess phylogenetic relationships within Lowryanthinae; and (3) re-assess the subtribal and generic limits within the tribe Athroismeae. New phylogenetic analyses based on plastid sequence data confirmed the position of Rochonia in Astereae. Jalantzia (Vernoniopsis) was resolved as sister to the subtribe Lowryanthinae and therefore transferred to Athroismeae. A new subtribe, Jalantziinae, is described to accommodate Jalantzia. Apodocephala is paraphyletic with respect to Lowryanthus, which is formally merged with Apodocephala. A description of the emended subtribe Madagasterinae containing Madagaster and Rochonia is presented.

The Afromontane and Afroalpine areas constitute some of the main biodiversity hotspots of Africa. They are particularly rich in plant endemics, but the biogeographic origins and evolutionary processes leading to this outstanding diversity are poorly understood. We performed phylogenomic and biogeographic analyses of one of the most species-rich plant genera in these mountains, Helichrysum (Compositae-Gnaphalieae). Most previous studies have focused on Afroalpine elements of Eurasian origin, and the southern African origin of Helichrysum provides an interesting counterexample. We obtained a comprehensive nuclear dataset from 304 species ( 50% of the genus) using target-enrichment with the Compositae1061 probe set. Summary-coalescent and concatenation approaches combined with paralog recovery yielded congruent, well-resolved phylogenies. Ancestral range estimations revealed that Helichrysum originated in arid southern Africa, whereas the southern African grasslands were the source of most lineages that dispersed within and outside Africa. Colonization of the tropical Afromontane and Afroalpine areas occurred repeatedly throughout the Miocene–Pliocene. This timing coincides with mountain uplift and the onset of glacial cycles, which together may have facilitated both speciation and intermountain gene flow, contributing to the evolution of the Afroalpine flora.

The monospecific genus Aitchisonia (Rubiaceae), a suffrutescent plant endemic to Afghanistan, Iran, and Pakistan, was merged in the genus Plocama of the monogeneric tribe Putorieae sensu Backlund et al. (Spermacoceae alliance, subfamily Rubioideae). This decision was based on the phylogenetic placement of the specimen Rafei and Zangooei 25651 (FUMH) erroneously identified as Aitchisonia rosea in Plocama. This specimen was later correctly re-identified as Plocama dubia, rending the position of Plocama rosea (= Aitchisonia rosea) in Plocama (thus Putorieae) doubtful. We reconstructed a new phylogeny of Spermacoceae alliance based on trnL-F and nrITS sequence data and using the Bayesian method to: 1) assess the phylogenetic placement of P. rosea within Rubioideae, using new material from Iran; 2) pinpoint the phylogenetic positions of Plocama asperuliformis, P. crucianelloides, P. dezfulensis, P. ehrendorferi, P. kandaharensis, P. szowitsii, and P. vassilczenkoi; and 3) re-assess the monophyly of Plocama bruguieri and P. eriantha. The trnL-F and nrITS trees further support the monophyly of the Rubieae complex, but were not fully congruent. The trnL-F tree resolved Plocama rosea as sister to tribe Rubieae (including Kelloggia), while the nrITS tree was inconclusive. We described a new monogeneric tribe Aitchisonieae to accommodate P. rosea. Our nrITS analysis resolved Plocama crucianelloides in the Plocama Middle-Eastern clade and P. asperuliformis, P. dezfulensis, P. ehrendorferi, P. kandaharensis, P. szowitsii, and P. vassilczenkoi in the Plocama Central-Asian clade, both sensu Rincón-Barrado et al. The non-monophyly of P. bruguieri and P. eriantha is confirmed.

Background – This contribution is part of an ongoing study on the taxonomy and the phylogenetic relationships of the Malagasy representatives of the tribe Pavetteae (Rubiaceae).

Material and methods – Taxonomic methods follow normal practice of herbarium taxonomy. A molecular study using the plastid markers rps16, trnT-F, petD, and accD-psa1, the nuclear ribosomal marker ITS and the nuclear MADS-box gene marker PI was executed.

Key results – Five new species are described from littoral, lowland, or mid-elevation humid forests in eastern Madagascar. They are characterized by compact inflorescences with small, sessile flowers, a densely pubescent style, large placentas with 2–3 immersed ovules, seeds with a small, superficial hilum not surrounded by a thickened annulus, and pollen grains with supratectal elements. The phylogenetic tree, which included three of the five new species, showed an unresolved backbone but high support for distal nodes grouping species. The new species form a distinct monophyletic clade among the other Malagasy Pavetteae genera and are recognised at genus level under the name Tarennella. Provisional IUCN Red List assessments show that Tarennella homolleana is Vulnerable, T. cordatifolia and T. sanguinea are Endangered, T. puberula is Critically Endangered, and T. coronata is Critically Endangered (Possibly Extinct).

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.

Four new species of the tribe Vanguerieae (Rubiaceae) from southern, southwestern and western Madagascar are described and illustrated. Two species belong to the genus Pyrostria Comm. ex Juss.: P. costata Klack. & Razafim. with small leaves and distinctly ribbed pollen presenters and fruits, and P. macrocarpa Klack. & Razafim. characterized by its large, obconical, 5 – 6-lobed fruits. The other two species belong to the Malagasy subendemic genus Peponidium Ar.nes: P. leroyi Klack. & Razafim., characterized by hairy leaves with ciliate margins, sparsely pubescent flowers and ribbed pollen presenters, and P. sessile Klack. & Razafim., distinct by its cordate almost sessile leaves and double-tipped corolla lobes. Risk of extinction assessments for all four species are presented, as well as the respective distribution maps.

Coussareeae are a Neotropical clade of morphologically heterogeneous plants in the subfamily Rubioideae of the coffee family (Rubiaceae). The tribe encompasses about 330 species assigned to ten genera: Bradea, Coccocypselum, Coussarea, Cruckshanksia, Declieuxia, Faramea, Heterophyllaea, Hindsia, Oreopolus, and Standleya. Historically, the genera of Coussareeae have rarely been considered closely related, and the widely defined Coussareeae were delimited based on molecular systematics without proposed morphological synapomorphies. In order to assess the tribe’s monophyly, as well as the generic limits, infrageneric relationships, and suprageneric relationships, multiple specimens per genus were sampled whenever possible and analyzed using multiple molecular loci with the Bayesian and maximum likelihood methods. The results of the phylogenetic analyses (all genera represented by multiple terminals are monophyletic, all genera are resolved with respect to each other, and three major suprageneric clades are resolved), coupled with herbarium and literature studies, were used to identify potential synapomorphic features. Non-molecular diagnostic features remain elusive for Coussareeae as a whole, but we have identified multiple diagnostic features and potential synapomorphies for each of the three major suprageneric clades: (1) Coussarea and Faramea(e.g., porate pollen grains with annuli bordering the pores); (2) Bradea, Coccocypselum, Declieuxia, Hindsia, and Standleya (e.g., colporate pollen grains with complex reticulate tecta); and 3) Cruckshanksia, Heterophyllaea, and Oreopolus (e.g., chartaceous, loculicidal capsules). The latter clade, distributed in different biomes of the Andes, is sister to the former two, both widely distributed in the Neotropics.

Faramea is characterized by white or blue, tetramerous corollas and blue-black, fleshy fruits with a single, large pyrene. Both infrageneric relationships and species boundaries are poorly understood in the genus. This study represents the first broad-scale phylogenetic study of Faramea, with 80 of the c. 170 species sampled, 24 by two or more specimens. We aimed to include specimens representing the entire geographical, morphological and ecological ranges of the genus. Morphological characters historically utilized to delimit infrageneric sections in Faramea (e.g. bract and pyrene forms) were also evaluated. Only one of the currently accepted infrageneric sections was recovered as monophyletic (within a complex of species from other sections) and none of the morphological features traditionally utilized to determine infrageneric relationships in the genus was found to be uniquely diagnostic of a larger clade. Some Faramea lineages appear to be geographically isolated, with several clades containing solely specimens collected in the Atlantic Forest biomes. Of the 24 species represented by at least two specimens, 11 were supported as monophyletic, ten as non-monophyletic and three were not resolved as either monophyletic nor non-monophyletic. The results of the present study constitute a good basis for future studies of taxonomy, biogeography and ecology of Faramea.

We investigated the historical biogeography of the Inuleae–Plucheinae (Asteraceae), a group of arid-adapted plants with partly unresolved generic circumscriptions, in order to understand its origin and spatiotemporal evolutionary history in relation to the Cenozoic climate shifts. Location Global, with highest species diversity in the Southern Hemisphere. The spatiotemporal biogeography of the Plucheinae was estimated by both a discrete method using a set of general distribution areas, and a relaxed random walk based on extant species distributions. The topology was time calibrated using a combination of secondary node ages and secondary derived rates for included loci. Our results indicate the median age of the Plucheinae to be approximately 15.4 Ma. The biogeographical analyses infer an ancestral origin in southern Africa, with the relaxed random walk analysis narrowing the uncertainty down to an area reaching from coastal Namibia to the western Kalahari. Africa was colonized in a (south)western–(north)eastern direction following the spread of arid habitats. Ancestral representatives of the Plucheinae colonized South America on at least three separate occasions (13.0–4.0, 4.3–3.1 and 4.1–3.7 Ma), with one subsequent spread to North America. Australia was colonized three times between 3.6 and 0.4 Ma. Madagascar and the Mascarenes were colonized at least seven times. The origin of the Plucheinae is estimated to the Namib region, with early speciations and radiations concurring with the timing of aridification of southern Africa, following the increase in strength of the Antarctic Circumpolar Current and subsequent formation of the Benguela Upwelling at c. 11.8 Ma. The current biogeographical distribution of the Plucheinae is best explained by several Neogene long-distance dispersal events from tropical Africa.

The Australasian Neonauclea is the largest genus of the tribe Naucleeae (subfamily Cinchonoideae, Rubiaceae) and is well known for its extensive radiation of myrmecophytic species. The genus is paraphyletic with respect to the genera Ludekia and Myrmeconauclea, and these three genera constitute the Neonauclea clade sensu Löfstrand et al. The Philippines is a center of species diversity of Neonauclea; however, its members have yet to be included in any molecular studies. We produced a phylogeny of the Neonauclea clade based on sequence data from nuclear (ETS and ITS) and plastid (rbcL and trnT-F) markers and including a large sampling of Neonauclea species from the Philippines. The resulting phylogeny was used to assess the phylogenetic positions and relationships of the Philippine Neonauclea species within the Neonauclea clade. We also reassessed the origins of myrmecophytism in the Neonauclea clade using ancestral state reconstructions. The sampled Philippine Neonauclea were resolved in five morphologically and geographically distinct clades. Our ancestral state reconstructions inferred a non-myrmecophytic ancestor for the Neonauclea clade, as shown by Razafimandimbison et al., and suggested at least two independent origins of myrmecophytism, one in myrmecophytic Myrmeconauclea and another in the myrmecophytic Neonauclea species from core Neonauclea. Losses of myrmedomes through multiple evolutionary reversals back to the non-myrmedome condition were inferred within core Neonauclea. Unlike the Bornean myrmecophytic lineages, our results favored a single origin of the Philippine endemic myrmecophytic Neonauclea.

 The genus Craterispermum  (Craterispermeae, Rubiaceae) is distributed in the tropical rain forests of Africa and Madagascar, with one morphologically variable species (Craterispermum microdon ) hitherto recognized in the Seychelles Archipelago. We conducted a Bayesian analysis of the combined ETS and ITS sequence data to: 1) test the monophyly of the Seychellois species of Craterispermum ; and 2) assess the phylogenetic relationships between the island populations. Our analyses supported the monophyly and, therefore, the single Malagasy origin of the Seychellois Craterispermum . The phylogenetic relationships between the three island populations were unresolved, since the Seychellois plants display a very low level of molecular variation. However, both herbarium and field studies revealed that the Craterispermum  taxa occurring on the islands of Mahé, Praslin, and Silhouette, are morphologically distinct and geographically separated. As a result of these studies, two new species, Craterispermum praslinense  and C. silhouettense , are described, to accommodate the Praslin and Silhouette populations, respectively, and C. microdon  is restricted to the population on Mahé Island. A new taxonomic account for the Seychellois Craterispermum , and an identification key to the three species present in the archipelago, are provided. A provisional conservation status of each species, according to the IUCN Categories and Criteria, is presented.

We present a taxonomic revision of the genus Jumellea (Angraecinae; Orchidaceae) in the Mascarenes based on morphological study and field observations. We examined 328 specimens mostly from the MAU, P and REU, and recognise nine species. We provide a key, morphological descriptions, distributions, habitats, phenologies and conservation assessments following the Red List categories and criteria (IUCN). All nine species are present on Réunion with two being endemic there, and five have been confirmed on Mauritius, none of them endemic. The single species recorded for Rodrigues is also the only one found on all three islands of the Mascarenes and Madagascar. Five species are endemic to the Mascarene Archipelago, whereas the other four also occur in Madagascar. All nine species qualify as threatened with extinction on at least one of the islands of the Mascarenes. Two species are probably extinct on one island, and only two species on Réunion are not threatened.

A taxonomic revision of the mostly Malagasy genus Saldinia (Rubiaceae, Rubioideae, Lasiantheae) was conducted by Bremekamp 66 years ago. However, no holotype was selected for four of his 22 species and no distribution maps of these species were presented. The objectives of this study are, therefore, a) to produce a world checklist of the species of Saldinia with information about the type specimens, b) to lectotypify four Saldinia species, and c) to provide new distribution maps of the 22 described species. A total of 966 specimens of Saldinia (including 27 types) from the P herbarium were examined together with the protologues of all recognized species. The geographic coordinates of the 22 species recognized by Bremekamp were gathered from the specimen labels. We present a world checklist of Saldinia and four lectotypifications for Saldinia axillaris, S. acuminata, S. pallida, and S. stenophylla, and provided new distribution maps for all 22 species of Saldinia. The checklist will serve as a basis for future systematic studies in Saldinia and the species distribution maps will be useful for the ongoing taxonomic revision of the genus. 

 The taxonomic positions and phylogenetic relationships of six Pavetteae species endemic to Madagascar were tested with a phylogenetic study of the Afro-Madagascan representatives of the tribe Pavetteae based on sequence data from six markers rps16, trnT-F, petD, accD-psa1, PI and ITS. The six species were resolved into four well-supported and morphologically distinct clades which we here formally recognise at generic level. The new genera are the monospecific Exallosperma and Pseudocoptosperma, each with a single species, and Helictosperma and Tulearia, each with two species. Each genus is characterised by one or more autapomorphies or by a unique combination of plesiomorphic characters. Mostly, the distinguishing characters are found in fruit and seed; Exallosperma differs from all other Pavetteae genera by the fruit consisting of two stony pyrenes, each with a single laterally flattened seed with irregularly distributed ridges on the surface; Helictosperma is unique by its single spherical seed rolled-in on itself in the shape of a giant pill-millipede. Pseudocoptosperma is characterised by the combination of three ovules pendulous from a small placenta and triangular stipules with a strongly developed awn, whereas Tulearia is characterised by robust sericeous flowers, small leaves, uni- or pauciflorous inflorescences and fruits with two pyrenes, each with a single ruminate seed. 

The four new genera show marked adaptations to the dry habitats in which they grow. They represent multiple radiations into drylands and highlight the importance of the dry forest and scrub vegetation in western, southern and northern Madagascar for plant biodiversity. The description of the four new genera shows that the tribe Pavetteae exhibits the same pattern as many plant groups in Madagascar, which are characterised by a high proportion of endemic genera comprising a single or a few species.

there. The Seychelles biota contains a mix of ancient taxa with Gondwanan origins and young taxa that arrived there via dispersals. We investigate the phylogenetic position of an enigmatic, critically endangered, Seychellean endemic of the coffee family (Rubiaceae), Psathura/Psychotria sechellarum, and assess whether its presence on the granitic islands of the Seychelles is the result of vicariance or long-distance dispersal. Phylogenetic relationships of the family were reconstructed based on the Bayesian and maximum-likelihood phylogenetic analyses of sequence data from five plastid markers of 107 terminals. Divergence times were estimated using a Bayesian-based method. Psathura/Psychotria sechellarum is distantly related to Psychotria s.l. (including Psathura), and is strongly supported as sister to the Central African genus Colletoecema. Their striking morphological differences, coupled with their geographic separation and genetic distinctness, support the recognition of the new genus Seychellea and new tribe Seychelleeae to accommodate the Seychellean species. The Colletoecema-Seychellea clade constitutes an early-divergent lineage in the subfamily Rubioideae, with an old stem and a young crown ages estimated to be in the Late Cretaceous and late Oligocene-early Pliocene, respectively. Colletoecema diverged from Seychellea in the late Oligocene-early Pliocene and their respective crown ages are inferred to be late Miocene-middle Pleistocene and Pleistocene, respectively. The ancestor of the two genera was likely present in Africa, and reached the Seychelles via avian dispersal. Unlike Colletoecema with three species, Seychellea is monospecific, with very few individuals left in the wild. The species should be a top candidate for conservation priority, as its extinction would cause loss of genetic diversity of this entire lineage.

 The species-rich genus Impatiens (Balsaminaceae) is represented in Madagascar by no less than 260 species. We conducted molecular phylogenetic analyses of the Malagasy Impatiens based on nuclear and plastid data and 52 accessions (representing 33 species) to: 1) reassess the monophyly of the Malagasy Impatiens; 2) assess the monophyly of the sections Preimpatiens (Humblotianae and Vulgare groups) with spurs and Trimorphopetalum without spurs as delimited by Perrier de la Bâthie, as well as that of the subgenera Impatiens and Trimorphopetalum as defined by Fischer and Rahelivololona; 3) infer the current status of some morphologically variable species; and 4) test whether the species of Impatiens from the Marojejy National Park form a monophyletic group. The Malagasy Impatiens are further confirmed to be paraphyletic with respect of the Comorian I. auricoma. The present sectional and subgeneric classifications of the Malagasy Impatiens are partly supported, with strong support for the monophyly of the sect. or subgen. Trimorphopetalum. Section Preimpatiens was not supported as monophyletic and neither the Humblotianae group nor the Vulgare group is monophyletic. Impatiens elatostemmoides, I.“hammarbyoides”, I. inaperta, I. lyallii and I. manaharensis are either para- or polyphyletic and may represent morpho-species. The Impatiens species from the Marojejy National Park do not form a monophyletic group and therefore are suggested to be derived from numerous independent colonisation events from all over Madagascar followed by subsequent diversifications.

A first record of the genus Dentella L. (Rubiaceae) from Madagascar is reported here. Dentella repens (L.) J.R. Forst. & G. Forst. was collected for the first time in the northwestern part of the island, within Analalava District of the Sofia Region. The material collected possesses all the salient characters of the species (e.g., creeping, prostrate herb, toothed corolla lobes, indehiscent fruits covered by transparent, flattened, bulbous-tipped trichomes). We postulate that the species has most likely recently reached Madagascar via long-distance dispersal either from Sri Lanka, where it is native, or Mauritius, where it has become naturalized.

CircumscriptionsoftheAustralasiantribesOphiorrhizeaeandPomazoteae(Rubiaceae)aswellastheirgenericrelationships and limits have long remained unsettled. These tribes were originally delimited by Bremekamp based on the lack of raphides and testa cell patterns (thick- versus thin-walled testa cells, respectively). Some authors have synonymized the two or treated Pomazoteae as a syn- onym of other tribes despite the fact that the matter has never been sufficiently addressed. We performed molecular phylogenetic analyses of Ophiorrhizeae sensu Bremer & Manen (i.e., comprising Coptophyllum, Lerchea, Neurocalyx, Ophiorrhiza, Spiradiclis and Xanthophytum) based on sequence data from four plastid and two nuclear markers. Coptophyllum (= Pomazota, type of Pomazoteae), Lerchea and Xanthophytum together with seven other genera, were traditionally classified in Pomazoteae. We also investigated for the first time the two Pomazoteae genera Keenania and Leptomischus. Our analyses resolved Leptomischus as sister to the Rubioideae tribe Argostemmateae and we here formally classify this genus in that tribe. Ophiorrhizeae sensu Bremer and Manen is paraphyletic with re- spect to Keenania. Pomazoteae is polyphyletic, with most of its genera (including Coptophyllum) belonging in Ophiorrhizeae. Its tribal status cannot be held. Testa cell patterns are evolutionarily labile, and seem to have no phylogenetic value at tribal level. Our study strongly supports a broadly delimited Ophiorrhizeae that contains mostly suffrutescent herbs. Within Ophiorrhizeae as here defined, Neurocalyx is sister to the rest of the tribe, followed by Xanthophytum. The Coptophyllum-Lerchea clade is sister to a large clade formed by Keenania, Ophiorrhiza and Spiradiclis. Ophiorrhiza is paraphyletic with respect to Keenania and Spiradiclis, and was resolved in two well-supported lineages, the Ophiorrhiza-Keenania and Ophiorrhiza-Spiradiclis lineages. Accordingly, we formally transferred all validly published names from Keenania and Spiradiclis to Ophiorrhiza, resulting in 40 new combinations and 15 new names. 

PREMISE OF THE STUDY: The Western Indian Ocean Region (WIOR) is a biodiversity hotspot providing an ideal setting for exploring the origins of insular biodiversity and dynamics of island colonization. We aimed to investigate the origins of the WIOR Psychotrieae alliance (Rubiaceae) with typically small, probably mainly bird-dispersed drupes, and the timing and direction or sequence of its colonization events in the region.

METHODS: We used the program BEAST to estimate divergence times and Lagrange for biogeographic reconstruction.

KEY RESULTS: The alliance has reached the WIOR at least 14 times via dispersals from Africa along with Asia and the Pacifi c mostly during the last 10 My, with at least one back-colonization to Africa. We inferred the earliest dispersal to Madagascar from the Pacifi c or Asia in the Miocene and numerous out-of-Madagascar dispersals to the nearby archipelagos but no dispersal out of those archipelagos. Gynochthodes with multiple fruits reached Madagascar twice from the Pacifi c possibly via ocean drifting. Psychotria with dry fruits (schizocarps) colonized Madagascar from the Pacific or Asia before reaching the Comoros from Madagascar possibly via wind dispersal.

CONCLUSIONS: This study reinforces the pivotal role of dispersal in shaping the WIOR biodiversity and as the critical initiating step in the generation of endemic biodiversity on its islands. The WIOR alliance shows strong Asian and Pacifi c affi nities despite the proximity of the region to Africa. Madagascar has served as a stepping-stone for subsequent dispersal to the rest of the region. The Afro-Malagasy-Seychelles genus Craterispermum and the Malagasy Puffia may represent relictual lineages.

The use of molecular data in phylogenetic reconstruction during more than three decades has greatly improved our under-standing of the macroevolutionary history of the coffee family (Rubiaceae) and has provided a solid basis for improvement of its clas-sification. Based on the results of 130 studies, among them most recent phylogenomic works, we present a consensus phylogeny and arobust classification of Rubiaceae that shed light on the evolutionary success of this highly diverse angiosperm family and can serveas a framework for ecological and evolutionary studies. There are more than 14,000 species and about 580 accepted genera of Rubia-ceae that are assigned to 71 tribes, of which 68 are classified in two subfamilies (Dialypetalanthoideae with 38 tribes and Rubioideaewith 30 tribes). Three tribes (Acranthereae, Coptosapelteae, Luculieae) remain unclassified as to subfamily. Sixty-three of these71 tribes are assigned to nine informal alliances (four in Rubioideae and five in Dialypetalanthoideae). These tribes are listed in al-phabetical order within their respective alliances. Five tribes, one (Coussareeae) in Rubioideae and four (Airospermeae, Jackieae,Retiniphylleae, Steenisieae) in Dialypetalanthoideae, are excluded from these alliances due to unclear or conflicting phylogeneticpositions. Thirty-six tribes retain their tribal status but receive new generic limits to remedy their previous para- or polyphyleticnature. Twenty-nine tribes not implemented in previous classifications have been added, of which three (Chioneae, Glionnetieae,Temnopterygeae) are newly described here. Basic information on phylogenies, distributions, former classifications, and useful refer-ences to previous works are provided for all accepted tribes, and future perspectives are discussed.

Background and aims The tribe Danaideae (Rubiaceae) is almost

exclusively endemic to the Western Indian Ocean Region (WIOR), encompassing the

genera Danais, Payera and Schismatoclada that occur in humid and sub-humid

climates. Much of the species diversity is endemic to restricted, remote and/or

mountainous areas of the WIOR, and recent field work on Madagascar indicates

substantial unknown diversity of the Danaideae. Further, the monophyly of the

Malagasy genera Payera and Schismatoclada has been questioned in previous work,

species delimitations and phylogenetic relationships within the genera are poorly

understood, and distribution and evolution of gross morphological features have not

been assessed.

 Methods We conducted morphological investigations, and produced robust

phylogenies of Danaideae based on nuclear and plastid sequence data from 193

terminals. Ample plant material has been newly collected in the WIOR for the

purpose of the present study, including potentially new species unknown to science.

We performed Bayesian non-clock and relaxed-clock analyses employing three

alternative clock models of a dataset with a dense sample of taxa from the entire

geographic ranges of Danaideae. Based on the results, we discuss species diversity

and distribution, relationships, and morphology in Danaideae.

 Key results Our results demonstrate the monophyly of Danaideae, its three

genera, and 43 species. Nine species are resolved as non-monophyletic. Many

geographically distinct but morphologically heterogeneous lineages were identified,

and morphological features traditionally considered diagnostic of subgroups of the

genera, used e.g. in species identification keys, are not clade-specific.

 Conclusions Our results demonstrate that Madagascar contains ample hereto

undocumented morphological and species diversity of Danaideae. Our novel approach

to perform molecular phylogenetic analyses as a precursor to taxonomic revisions

provides numerous benefits for the latter. There are tentative indications of parallel

northward diversification in Payera and Schismatoclada on Madagascar, and of

geographic phylogenetic clustering despite the anemochorous condition of Danaideae

Tropical Asia is one of the centers of species diversity of flowering plants, in particular the coffee family (Rubiaceae). Prismatomerideae (the Psychotrieae alliance, subfamily Rubioideae) are a mostly Southeast Asian tribe encompassing four genera of shrubs and small trees (monospecific Gentingia and Motleyia, Prismatomeris with 16 spp., Rennellia with 4–5 spp.). We conducted molecular phylogenetic analyses of this group based on the nuclear and plastid sequence data from six markers and using Bayesian inference. The main goal was to produce a robust phylogeny of the tribe, which was subsequently used to (1) reassess its monophyly and phylogenetic position within the Psychotrieae alliance; (2) rigorously test the monophyly of Prismatomeris and Rennellia; (3) assess the phylogenetic relationships between the genera; and (4) evaluate the phylogenetic value of the inflorescence type currently used for species recognition in Rennellia. Motleyia was not sequenced due to the lack of material, and therefore its affinity with the other genera was assessed based on morphology. The tribe was supported as monophyletic and resolved as sister to the (Gaertnereae (Mitchelleae-Morindeae)) clade. The monophyly of Prismatomeris sensu Johansson was strongly supported, but we argue for the merging of the monospecific genus Motleyia into Prismatomeris based on their strong morphological similarities coupled with the paraphyly of Prismatomeris with respect to Motleyia. Rennellia was strongly supported as paraphyletic with respect to Gentingia. We propose the transfer of the monospecific genus Gentingia to Rennellia, also consistent with their strong morphological resemblance. Prismatomerideae were resolved in two major sister lineages, the Prismatomeris and Rennellia clades, corresponding to our broadly delimited Prismatomeris and Rennellia. Three well-supported and morphologically distinct subclades were identified within Rennellia s.l., of which one was represented by Rennellia subsessilis, with sessile and reduced umbel-like inflorescences bearing two to four flowers. The other two subclades have compound spike-like (or sub-raceme-like) and raceme-like inflorescences, an important distinction in species-group recognition. We conclude that inflorescence type shows a strong phylogenetic signal and is, therefore, a reliable feature for recognizing groups of species in Rennellia. Additional taxonomic characters are, however, needed for teasing apart closely related species with the same inflorescence types. Subsequent to our taxonomic revision, the tribe Prismatomerideae comprises two genera: Prismatomeris and Rennellia. One and two new combinations, respectively, are presented, bringing the total number of species in the tribe to 25, of which 17 are in Prismatomeris and 8 in Rennellia. A new species key to Rennellia s.l. is presented.

 A new species Schismatoclada spathulata  D. Strid & Razafim. (Rubiaceae)  from the Marojejy National Park in northeastern Madagascar is described and illustrated. The new species differs from the other Schismatoclada Baker species by the combination of spathulate leaves and ellipsoid seeds that are bilaterally flattened and broadly winged all around. It is known only from the Beondrika Massif of the Marojejy National Park, and has not been seen below 1200 m altitude. It is assigned a preliminary conservation status of “Least Concern” following IUCN Red List, as no sign of degradation of its habitat has been observed.

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.

Danais Comm. ex Vent. (Rubiaceae) comprises about 49 species in Madagascar, the Mascarenes, and East Africa. A new species taxonomy is presented here, with an updated description and key to all Danais species, details of taxonomic changes, lectotypifications. Four previously described species that were excluded from Danais are reinstated here: D. aptera Wedd. ex Homolle, D. baccata Homolle, D. coerulea Homolle ex Cavaco, and Sabicea verticillata Wernham under the replacement name Danais confusa C.M. Taylor. Identities and circumscriptions of some previously described Danais species are revised. The taxonomic circumscription of D. aurantiaca Baker is narrowed by the separation of a new species, D. reticulata C.M. Taylor; D. cernua Baker is diagnosed here by some different characters; D. fragrans (Lam.) Pers. in the Mascarenes is separated from plants of Madagascar formerly included in this species, now named D. lyallii Baker; D. longipedunculata Homolle and D. masoalana C.M. Taylor are no longer distinguishable and are synonymized; D. nigra Homolle is narrowed by the separation of the new species D. puffiana Razafim. & C.M. Taylor; D. perrieri Homolle is distinct form D. nigra Homolle; and D. terminalis Boivin ex Drake is still poorly known, but its circumscription is clarified and narrowed. Seven new species of Danais are described: D. coriacea C.M. Taylor, D. gracilis C.M. Taylor, D. ovata C.M. Taylor, D. puffiana Razafim. & C.M. Taylor, D. reticulata, D. sambiranensis C.M. Taylor, and D. schatzii C.M. Taylor. All the new species are threatened using the IUCN Red List Criteria: two are preliminarily assessed as “Critically Endangered” and five as “Endangered”.

 Bourreria scabra Thulin & Razafim.  (Boraginaceae), a new species from southern Madagascar, is described and illustrated. The plant was previously sometimes treated as conspecific with  Bourreria lyciacea Thulin [[  Hilsenbergia lyciacea (Thulin) J.S. Mill.] in Somalia and Kenya. However,  Bourreria scabra differs markedly from  Bourreria lyciacea by its smaller corolla, finely pubescent outside and with shorter lobes, by its practically unbranched style, by its smaller fruits more or less enclosed by the calyx, and by its smaller pyrenes with several low ridges forming an irregular reticulation on the outside. Bourreria scabra differs from all other species of  Bourreria P. Browne in Madagascar by the very rough upper surface of the leaves. The species is widespread in spiny dry forests in southern Madagascar, with occurrences in the Andohahela and Tsimanampetsotsa National Parks and the Beza Mahafaly Reserve. The new species is assigned the category of “Near Threatened” using the IUCN Red List Criteria.

Ormocarpopsis anosyana Thulin & Razafim. (Fabaceae), a new species from the Anosy Region of south-eastern Madagascar, is described and illustrated. According to phylogenetic analyses based on nuclear ribosomal ITS sequences, the new species is, with strong support, sister to Ormocarpopsis mandrarensis Dumaz-le-Grand, another species confined to southeastern Madagascar. Ormocarpopsis anosyana differs markedly from Ormocarpopsis mandrarensis by its generally smaller leaflets with the secondary and tertiary venation drying more or less blackish beneath, by its shorter hypanthium, by its smaller calyx with the lowest tooth about as long as the others, by its wing-petals that are much longer than the keel, by its glabrous ovary, and by its slightly articulated fruits. Ormocarpopsis anosyana is known only from two collections from a single patch of spiny dry forest east of Imonty. It is assigned a preliminary conservation status as “Endangered”.

Premise of research. With wind-pollinated flowers and partly temperate distribution, the tribe Anthospermeae stands out in the otherwise mostly animal-pollinated and tropical coffee family (Rubiaceae). Nevertheless, few attempts to resolve the phylogeny of the group have been made, and inter- and infrageneric relationships have been only partly addressed. Here we investigate evolutionary relationships and generic and subtribal delimitations of Anthospermeae. We assess the influence of alternative evolutionary rate models on topology and node support.

Methodology. Using sequence data from the nuclear (nrITS and nrETS) and plastid (atpB-rbcL, ndhF, rbcL, rps16, and trnT-trnF) genomes collected for a broad sample of taxa, we conducted Bayesian analyses using nonclock, strict clock, and relaxed clock models. The resulting topologies and support values were compared, and the relative fit of evolutionary models to our data was evaluated. Marginal likelihood estimates were used to discriminate between the competing rate models.

Pivotal results. The monophyly of Anthospermeae was confirmed with Carpacoceresolved as sister to the remaining species. We found several cases of supported topological conflict between results based on nuclear and plastid data, but the deepest splits of the tribe were congruent among all analyses and incompatible with traditional subtribal delimitations of Anthospermeae. Monophyly of the genera Anthospermum, Nenax, and Coprosma was not supported. While the relaxed clock model was consistently favored over the nonclock and strict clock models for all data sets, the use of the different models had little impact on phylogenetic results.

Conclusions. We propose a revised subtribal classification of Anthospermeae, including a new subtribe, the monogeneric Carpacocinae. Introgression/hybridization and incomplete lineage sorting are the most likely causes for the plastid-nuclear incongruences detected for Anthospermeae, but their relative contribution could not be concluded.

Subfamily Rubioideae is the largest of the main lineages in the coffee family

(Rubiaceae), with over 8,000 species and 29 tribes. Phylogenetic relationships

among tribes and other major clades within this group of plants are still

only partly resolved despite considerable efforts. While previous studies have

mainly utilized data from the organellar genomes and nuclear ribosomal DNA,

we here use a large number of low-copy nuclear genes obtained via a target

capture approach to infer phylogenetic relationships within Rubioideae. We

included 101 Rubioideae species representing all but two (the monogeneric

tribes Foonchewieae and Aitchinsonieae) of the currently recognized tribes,

and all but one non-monogeneric tribe were represented by more than

one genus. Using data from the 353 genes targeted with the universal

Angiosperms353 probe set we investigated the impact of data type, analytical

approach, and potential paralogs on phylogenetic reconstruction. We inferred

a robust phylogenetic hypothesis of Rubioideae with the vast majority (or

all) nodes being highly supported across all analyses and datasets and few

incongruences between the inferred topologies. The results were similar to

those of previous studies but novel relationships were also identified. We

found that supercontigs [coding sequence (CDS) C non-coding sequence]

clearly outperformed CDS data in levels of support and gene tree congruence.

The full datasets (353 genes) outperformed the datasets with potentially

paralogous genes removed (186 genes) in levels of support but increased

gene tree incongruence slightly. The pattern of gene tree conflict at short

internal branches were often consistent with high levels of incomplete lineage

sorting (ILS) due to rapid speciation in the group. While concatenationand

coalescence-based trees mainly agreed, the observed phylogenetic

discordance between the two approaches may be best explained by

their differences in accounting for ILS. The use of target capture data 

greatly improved our confidence and understanding of the Rubioideae

phylogeny, highlighted by the increased support for previously uncertain

relationships and the increased possibility to explore sources of underlying

phylogenetic discordance.

Genome skimming (shallow whole-genome sequencing) offers time-and cost-efficient production of large amounts of DNA data that can be used to address unsolved evolutionary questions. Here we address phylogenetic relationships and topological incongruence in the tribe Anthospermeae (Rubiaceae), using phylogenomic data from the mitochondrion, the nuclear ribosomal cistron, and the plastome. All three genomic compartments resolve relationships in the Anthospermeae; the tribe is monophyletic and consists of three major subclades. Carpacoce Sond. is sister to the remaining clade, which comprises an African subclade and a Pacific subclade. Most results, from all three genomic compartments, are statistically well supported; however, not fully consistent. Intergenomic topological incongruence is most notable in the Pacific subclade but present also in the African subclade. Hybridization and introgression followed by organelle capture may explain these conflicts but other processes, such as incomplete lineage sorting (ILS), can yield similar patterns and cannot be ruled out based on the results. Whereas the null hypothesis of congruence among all sequenced loci in the individual genomes could not be rejected for nuclear and mitochondrial data, it was rejected for plastid data. Phylogenetic analyses of three subsets of plastid loci identified using the hierarchical likelihood ratio test demonstrated statistically supported intragenomic topological incongruence. Given that plastid genes are thought to be fully linked, this result is surprising and may suggest modeling or sampling error. However, biological processes such as biparental inheritance and inter-plastome recombination have been reported and may be responsible for the observed intragenomic incongruence. Mitochondrial insertions into the plastome are rarely documented in angiosperms. Our results indicate that a mitochondrial insertion event in the plastid trnSGGA – rps4 IGS region occurred in the common ancestor of the Pacific clade of Anthospermeae. Exclusion/inclusion of this locus in phylogenetic analyses had a strong impact on topological results in the Pacific clade.

In this study of evolutionary relationships in the subfamily Rubioideae (Rubiaceae), we takeadvantage of the off-target proportion of reads generated via previous target capturesequencing projects based on nuclear genomic data to build a plastome phylogeny andinvestigate cytonuclear discordance. The assembly of off-target reads resulted in a comprehensive plastome dataset and robust inference of phylogenetic relationships, where mostintratribal and intertribal relationships are resolved with strong support. While the phylogenetic results were mostly in agreement with previous studies based on plastome data, novelrelationships in the plastid perspective were also detected. For example, our analyses ofplastome data provide strong support for the SCOUT clade and its sister relationship to theremaining members of the subfamily, which differs from previous results based on plastiddata but agrees with recent results based on nuclear genomic data. However, severalinstances of highly supported cytonuclear discordance were identified across the Rubioideae phylogeny. Coalescent simulation analysis indicates that while ILS could, by itself,explain the majority of the discordant relationships, plastome introgression may be the better explanation in some cases. Our study further indicates that plastomes across the Rubioideae are, with few exceptions, highly conserved and mainly conform to the structure, genecontent, and gene order present in the majority of the flowering plants.

In this study of evolutionary relationships in the subfamily Rubioideae (Rubiaceae), we takeadvantage of the off-target proportion of reads generated via previous target capturesequencing projects based on nuclear genomic data to build a plastome phylogeny andinvestigate cytonuclear discordance. The assembly of off-target reads resulted in a compre-hensive plastome dataset and robust inference of phylogenetic relationships, where mostintratribal and intertribal relationships are resolved with strong support. While the phyloge-netic results were mostly in agreement with previous studies based on plastome data, novelrelationships in the plastid perspective were also detected. For example, our analyses ofplastome data provide strong support for the SCOUT clade and its sister relationship to theremaining members of the subfamily, which differs from previous results based on plastiddata but agrees with recent results based on nuclear genomic data. However, severalinstances of highly supported cytonuclear discordance were identified across the Rubioi-deae phylogeny. Coalescent simulation analysis indicates that while ILS could, by itself,explain the majority of the discordant relationships, plastome introgression may be the bet-ter explanation in some cases. Our study further indicates that plastomes across the Rubioi-deae are, with few exceptions, highly conserved and mainly conform to the structure, genecontent, and gene order present in the majority of the flowering plants.

Wendlandia, as currently circumscribed, is a genus of Rubiaceae comprising about 90 species mainly in tropical and subtropical Asia. By sampling species from all four series (Clavigerae, Euexsertae, Montigenae, Subinclusae) and all tribes in the subfamily Dialypetalanthoideae, we examined the monophyly of Wendlandia based on phylogenetic reconstruction using the nuclear ribosomal internal transcribed spacer and four plastid DNA regions. Wendlandia was resolved as biphyletic, consisting of two distantly related lineages that correspond to the monotypic series Clavigerae (Wendlandia pendula), sister to the Chinese endemic genus Trailliaedoxa, and a clade containing the remainder sampled members of Wendlandia. Based on the isolated phylogenetic position of W. pendula and its unique morphological characteristics compared to the recognized tribes of the Vanguerieae alliance, we herein erect a new monotypic genus, Clavistigma, and a new tribe, Clavistigmeae to accommodate the unique species. The secondary pollen presentation and the unique seed morphology were firstly described for the species. The divergence time between Clavistigma and Trailliaedoxa was dated back to 13.8 mya, coinciding with the climate change in northwestern Yunnan driven by the uplift Tibet Plateau and the river incision in the Hengduan Mountains during the Miocene and Late Pliocene.