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Background: Knowledge of Carex L. (true sedges) and Hypericum L. (St. John's wort) in the Neotropics is fragmentary. New information: As a result of a fieldwork campaign in Ecuador and revision of herbarium collections (K, QCA and QCNE), we present here relevant records of twelve Carex (Cyperaceae) and four Hypericum (Hypericaceae) species. Regarding Carex, we present the novel report for South America of C. aztecica, as well as the first Ecuadorian records for C. brehmeri, C. collumanthus, C. fecunda, C. melanocystis and C. punicola. The three later records have additional biogeographical significance, as they represent the new northern limit of these species. We also include observations for another five species included in the Ecuadorian Red List of Endemic Plants. As a result, the list of native Carex reported for Ecuador would now include 52 taxa. With regard to Hypericum, we include the new report of H. sprucei for the province of Bolívar, and the confirmation of the presence of three rare species (H. acostanum, H. matangense, H. prietoi) in their type localities, although with extremely low population sizes. We discuss their conservation status and implications. [ABSTRACT FROM AUTHOR]

The origins and evolution of the outstanding Neotropical biodiversity are a matter of intense debate. A comprehensive understanding is hindered by the lack of deep-time comparative data across wide phylogenetic and ecological contexts. Here, we quantify the prevailing diversification trajectories and drivers of Neotropical diversification in a sample of 150 phylogenies (12,512 species) of seed plants and tetrapods, and assess their variation across Neotropical regions and taxa. Analyses indicate that Neotropical diversity has mostly expanded through time (70% of the clades), while scenarios of saturated and declining diversity account for 21% and 9% of Neotropical diversity, respectively. Five biogeographic areas are identified as distinctive units of long-term Neotropical evolution, including Pan-Amazonia, the Dry Diagonal, and Bahama-Antilles. Diversification dynamics do not differ across these areas, suggesting no geographic structure in long-term Neotropical diversification. In contrast, diversification dynamics differ across taxa: plant diversity mostly expanded through time (88%), while a substantial fraction (43%) of tetrapod diversity accumulated at a slower pace or declined towards the present. These opposite evolutionary patterns may reflect different capacities for plants and tetrapods to cope with past climate changes. [ABSTRACT FROM AUTHOR]

Summary: Angiosperm lineages in aquatic environments are characterized by high structural and functional diversity, and wide distributions. A long‐standing evolutionary riddle is what processes have caused the relatively low diversity of aquatic angiosperms compared to their terrestrial relatives.We use diversification and ancestral reconstruction models with a comprehensive > 10 000 genus angiosperm phylogeny to elucidate the macroevolutionary dynamics associated with transitions of terrestrial plants to water.Our study reveals that net diversification rates are significantly lower in aquatic than in terrestrial angiosperms due to lower speciation and higher extinction. Shifts from land to water started early in angiosperm evolution, but most events were concentrated during the last c. 25 million years. Reversals to a terrestrial habitat started only 40 million years ago, but occurred at much higher rates. Within aquatic angiosperms, the estimated pattern is one of gradual accumulation of lineages, and relatively low and constant diversification rates throughout the Cenozoic.Low diversification rates, together with infrequent water transitions, account for the low diversity of aquatic angiosperms today. The stressful conditions and small global surface of the aquatic habitat available for angiosperms are hypothesized to explain this pattern. [ABSTRACT FROM AUTHOR]

Aim: The Neotropics currently host outstanding levels of species richness, with one‐third of the global tetrapod species. The underlying causes of these extraordinary levels of biodiversity are a topic debated in evolutionary ecology, but the main processes at work remain elusive. Location: Neotropics. Time period: Cenozoic and Mesozoic. Major taxa studied: Tetrapods. Methods: Using global phylogenies for amphibians, birds, lepidosaurs and mammals, biogeographical and time‐variable (trait‐dependent and trait‐independent) diversification models, we examined changes in speciation and extinction rates through time in the Neotropics in relationship to other areas of the world, and estimated the time of Neotropical colonizations. Results: We found that from the origin of lepidosaurs and mammals until the Pliocene (the Miocene for birds), diversification rates within the Neotropics were lower than rates in other regions (i.e., turnover was high). Afterwards, extinction decreased relative to speciation, and Neotropical diversification outpaced diversification in other regions. Dispersal out of the Neotropics also increased after the Pliocene (the Miocene for birds), exceeding into‐the‐Neotropics migrations. For amphibians, diversification rates in the Neotropics have been higher than in other areas through time, and dispersal out of the Neotropics decreased in the Cenozoic. Main conclusions: The common view that the Neotropics are an ancient source of world species diversity, with high in situ speciation, dispersal to other areas and low extinction, might be true only for amphibians. For mammals, birds and lepidosaurs, the Neotropics acted as a diversity sink from their origin until the Miocene–Pliocene (i.e., diversification rates were lower and turnover higher than in other areas). Only afterwards did the region turn into a diversity source. Our study highlights that models accounting for rates of diversification that vary through time could improve our capacity to assess evolutionary dynamics over long time‐scales. [ABSTRACT FROM AUTHOR]

Phylogenetic studies of globally distributed taxa are crucial to estimate the mode and tempo of common intercontinental biogeographic processes. However, few of these studies have focused on invertebrates, mainly because their taxonomy and species richness generally are highly neglected. Here we performed a morphological and mtDNA sequence-based species delineation analysis for 111 specimens of the cosmopolitan, speciose parasitoid wasp genus Spathius (Braconidae) and assessed its phylogenetic relationships and historical biogeography adding two nuclear markers. Seventy-one species of Spathius were delimited. Neither the monophyly of Spathiini, Spathius, nor its species groups were recovered. Based on the relaxed molecular clock and ancestral area reconstruction analyses, the Oriental appears as the most plausible region of origin for Spathius, whereas various intercontinental dispersal events probably played an important role in its species diversification. At least three and two dispersal events from the Oriental to the Ethiopian and Australian regions, respectively, were estimated to occur during the late Oligocene to mid-Miocene, c. 25-15 Mya. Dispersal to the Palaearctic and Nearctic from the Ethiopian region probably occurred during the early Miocene, c. 20 Mya. Our results overall reflect that the worldwide distribution of Spathius was acquired early in the evolutionary history of the lineage. [ABSTRACT FROM AUTHOR]

Many claims that uplift of the Qinghai‐Tibetan plateau (QTP) drove the divergences of extant high‐elevation biota have recently been challenged. For Mendacibombus bumblebees, high‐elevation specialists with distributions centred on the QTP, we examine broader explanations. We extend integrative biogeography to cover multiple contributing factors by using a framework of sequential filters: 1) molecular evidence from four genes is used to estimate phylogenetic relationships, with time calibration from a published estimate; 2) spatial evidence from current distributions is combined with the phylogeny and constrained by a model of short‐distance dispersal along mountain corridors to estimate ancestral distributions by both S‐DIVA and S‐DEC analysis; 3) geological evidence from the literature is used to constrain when high mountain ranges were uplifted to become potential corridors; and 4) climatological evidence from Mendacibombus niche‐evolution reconstructions and from palaeoclimate simulations is used to constrain when habitat was suitable in key gaps within corridors. Explanations for Mendacibombus distributions can be identified that require only short‐distance dispersal along mountain corridors, commensurate with the limited dispersal ability observed for bumblebees. These explanations depend on the timing of uplift of mountain ranges, regional climate change, and climate‐niche evolution. The uplift of the QTP may have contributed to the initial Oligocene divergence of the common ancestor of Mendacibombus from other bumblebees, but for the first two thirds of the history of Mendacibombus, only a single lineage has present‐day descendants. Divergence of multiple extant Mendacibombus lineages coincided with the Late Miocene–Pliocene uplift of externally connecting mountains, combined with regional climate cooling. These changes provided greater connectivity of suitable habitat, allowing these bumblebees to disperse out of the western QTP via new high bridges, escaping along the mountain corridors of the Tian Shan and Hindu Kush ranges, reaching eventually far to the west (Iberian Peninsula) and to the north‐east (Kamchatka). [ABSTRACT FROM AUTHOR]

Paliurus (Rhamnaceae) is a small genus with a narrow and disjunct distribution in East Asia and the Mediterranean. Fossil evidence from the Late Cretaceous to the present suggests it once had a broad geographic distribution, encompassing parts of India, North America, Asia, and Europe. To reconstruct the evolutionary history of Paliurus and understand the origin of the disjunction observed today in the Northern Hemisphere, phylogenetic and biogeographical reconstructions were performed based on ITS, trnL-F, and rbcL sequences. Paliurus is shown to be a monophyletic genus, which could be divided into two clades as suggested by previous studies. Biogeographical inference integrated with fossil information indicates that the origin and dispersal pattern of the genus coincide with the "Out-of-India" hypothesis. The genus may have originated in India or other parts of Gondwana and then dispersed to East Asia after the collision of the Indian subcontinent with Eurasia, and to North America via the Bering land bridge. Paliurus appears to have reached the Mediterranean region in the late Oligocene following closure of the Turgai Strait. The uplift of the Qinghai-Tibet Plateau and the advent of drying and cooling climates during the Miocene may have fragmented the distribution of the genus, shaping the biogeographical patterns observed today. Paliurus populations in different regions either became extinct or adapted to changes in local ecological conditions following global climatic shifts through geological time. [ABSTRACT FROM AUTHOR]

Global climate change and its impact on biodiversity levels have made extinction a relevant topic in biological research. Yet, until recently, extinction has received less attention in macroevolutionary studies than speciation; the reason is the difficulty to infer an event that actually eliminates rather than creates new taxa. For example, in biogeography, extinction has often been seen as noise, introducing homoplasy in biogeographic relationships, rather than a pattern-generating process. The molecular revolution and the possibility to integrate time into phylogenetic reconstructions have allowed studying extinction under different perspectives. Here, we review phylogenetic (temporal) and biogeographic (spatial) approaches to the inference of extinction and the challenges this process poses for reconstructing evolutionary history. Specifically, we focus on the problem of discriminating between alternative high extinction scenarios using time trees with only extant taxa, and on the confounding effect introduced by asymmetric spatial extinction - different rates of extinction across areas - in biogeographic inference. Finally, we identify the most promising avenues of research in both fields, which include the integration of additional sources of evidence such as the fossil record or environmental information in birth-death models and biogeographic reconstructions, the development of new models that tie extinction rates to phenotypic or environmental variation, or the implementation within a Bayesian framework of parametric non-stationary biogeographic models. [ABSTRACT FROM AUTHOR]

The Rand Flora is a well-known floristic pattern in which unrelated plant lineages show similar disjunct distributions in the continental margins of Africa and adjacent islands-Macaronesia-northwest Africa, Horn of Africa-Southern Arabia, Eastern Africa, and Southern Africa. These lineages are now separated by environmental barriers such as the arid regions of the Sahara and Kalahari Deserts or the tropical lowlands of Central Africa. Alternative explanations for the Rand Flora pattern range from vicariance and climate-driven extinction of a widespread pan-African flora to independent dispersal events and speciation in situ. To provide a temporal framework for this pattern, we used published data from nuclear and chloroplast DNA to estimate the age of disjunction of 17 lineages that span 12 families and nine orders of angiosperms. We further used these estimates to infer diversification rates for Rand Flora disjunct clades in relation to their higher-level encompassing lineages. Our results indicate that most disjunctions fall within the Miocene and Pliocene periods, coinciding with the onset of a major aridification trend, still ongoing, in Africa. Age of disjunctions seemed to be related to the climatic affinities of each Rand Flora lineage, with sub-humid taxa dated earlier (e.g., Sideroxylon) and those with more xeric affinities (e.g., Campylanthus) diverging later. We did not find support for significant decreases in diversification rates in most groups, with the exception of older subtropical lineages (e.g., Sideroxylon, Hypericum, or Canarina), but some lineages (e.g., Cicer, Campylanthus) showed a long temporal gap between stem and crown ages, suggestive of extinction. In all, the Rand Flora pattern seems to fit the definition of biogeographic pseudocongruence, with the pattern arising at different times in response to the increasing aridity of the African continent, with interspersed periods of humidity allowing range expansions. [ABSTRACT FROM AUTHOR]