Understanding Phenotypical Character Evolution in Parmelioid Lichenized Fungi (Parmeliaceae,Ascomycota)

Parmelioid lichens form a species-rich group of predominantly foliose and fruticose lichenized fungi encompassing a broad range of morphological and chemical diversity. Using a multilocus approach, we reconstructed a phylogeny including 323 OTUs of parmelioid lichens and employed ancestral character reconstruction methods to understand the phenotypical evolution within this speciose group of lichen-forming fungi. Specifically, we were interested in the evolution of growth form, epicortex structure, and cortical chemistry. Since previous studies have shown that results may differ depending on the reconstruction method used, here we employed both maximum-parsimony and maximum-likelihood approaches to reconstruct ancestral character states. We have also implemented binary and multistate coding of characters and performed parallel analyses with both coding types to assess for potential coding-based biases. We reconstructed the ancestral states for nine well-supported major clades in the parmelioid group, two higher-level sister groups and the ancestral character state for all parmelioid lichens. We found that different methods for coding phenotypical characters and different ancestral character state reconstruction methods mostly resulted in identical reconstructions but yield conflicting inferences of ancestral states, in some cases. However, we found support for the ancestor of parmelioid lichens having been a foliose lichen with a non-pored epicortex and pseudocyphellae. Our data suggest that some traits exhibit patterns of evolution consistent with adaptive radiation.     

Phylogeography and divergence date estimates of a lichen species complex with a disjunct distribution pattern

Disjunct species distributions may result from a combination of geologic events and long-distance dispersal. The foliose lichen species complex Leptogium furfuraceum-L. pseudofurfuraceum has an intercontinental disjunction pattern. Populations of this species complex are found in western North America, southern South America, Africa, and southern Europe. We conducted a phylogenetic study to reconstruct the biogeographic history of this species complex using two ribosomal genes (ITS and LSU) and a protein-coding gene (partial RPB2). Results indicated that the complex comprises four geographically restricted genetic lineages. A sister relationship was found between populations from the same hemispheres, incongruent with previous data derived from morphological characteristics and geographical classification schemes. Incorporating Bayesian ancestral area reconstruction and Bayesian divergence time estimation, we proposed an evolutionary hypothesis for the species complex. The results suggested that processes of biotic expansion via transoceanic dispersal were responsible for the species divergence and distribution patterns observed today. This study also expands the view that cryptic speciation is not a rare phenomenon among fungi and lichens.     

Origin and diversification of major clades in parmelioid lichens (Parmeliaceae, Ascomycota) during the Paleogene inferred by Bayesian analysis

There is a long-standing debate on the extent of vicariance and long-distance dispersal events to explain the current distribution of organisms, especially in those with small diaspores potentially prone to long-distance dispersal. Age estimates of clades play a crucial role in evaluating the impact of these processes. The aim of this study is to understand the evolutionary history of the largest clade of macrolichens, the parmelioid lichens (Parmeliaceae, Lecanoromycetes, Ascomycota) by dating the origin of the group and its major lineages. They have a worldwide distribution with centers of distribution in the Neo- and Paleotropics, and semi-arid subtropical regions of the Southern Hemisphere. Phylogenetic analyses were performed using DNA sequences of nuLSU and mtSSU rDNA, and the protein-coding RPB1 gene. The three DNA regions had different evolutionary rates: RPB1 gave a rate two to four times higher than nuLSU and mtSSU. Divergence times of the major clades were estimated with partitioned BEAST analyses allowing different rates for each DNA region and using a relaxed clock model. Three calibrations points were used to date the tree: an inferred age at the stem of Lecanoromycetes, and two dated fossils: Parmelia in the parmelioid group, and Alectoria. Palaeoclimatic conditions and the palaeogeological area cladogram were compared to the dated phylogeny of parmelioid. The parmelioid group diversified around the K/T boundary, and the major clades diverged during the Eocene and Oligocene. The radiation of the genera occurred through globally changing climatic condition of the early Oligocene, Miocene and early Pliocene. The estimated divergence times are consistent with long-distance dispersal events being the major factor to explain the biogeographical distribution patterns of Southern Hemisphere parmelioids, especially for Africa-Australia disjunctions, because the sequential break-up of Gondwana started much earlier than the origin of these clades. However, our data cannot reject vicariance to explain South America-Australia disjunctions.     

Tracing the evolution of amniote chromosomes

A great deal of diversity in chromosome number and arrangement is observed across the amniote phylogeny. Understanding how this diversity is generated is important for determining the role of chromosomal rearrangements in generating phenotypic variation and speciation. Gaining this understanding is achieved by reconstructing the ancestral genome arrangement based on comparisons of genome organization of extant species. Ancestral karyotypes for several amniote lineages have been reconstructed, mainly from cross-species chromosome painting data. The availability of anchored whole genome sequences for amniote species has increased the evolutionary depth and confidence of ancestral reconstructions from those made solely from chromosome painting data. Nonetheless, there are still several key lineages where the appropriate data required for ancestral reconstructions is lacking. This review highlights the progress that has been made towards understanding the chromosomal changes that have occurred during amniote evolution and the reconstruction of ancestral karyotypes.     

Phylogeny, biogeography, and evolution of sex expression in the southern hemisphere genus Leptinella (Compositae, Anthemideae)

Leptinella is exceptional in the Anthemideae (Compositae) in its evolution of dimorphic sex expression. A molecular phylogeny including 40 of its 42 described taxa based on nucleotide sequences from two plastid regions (psbA-trnH and trnC-petN spacers) and one nuclear marker (nrDNA ITS) is presented. Phylogenetic reconstruction was hampered by inadequate phylogenetic signal indicating recent radiation of species during the last 5Ma and high level of reticulate evolution presumably caused by hybridisation and polyploidisation. Nevertheless, Leptinella is nested within a paraphyletic genus Cotula that also engulfs the South American genus Soliva. Within Leptinella, the highly polyploid and sexually polymorphic subgenus Leptinella is monophyletic, while subgenus Oligoleima as well as subgenus Radiata are polyphyletic. We found a basal split between a lineage of Australian and New Guinean taxa and one of largely New Zealand taxa. At least five long-distance dispersal events have to be assumed in order to explain the distribution pattern in Leptinella. Among those, one is from New Zealand to Australia, while the others are dispersals to South America and to several subantarctic islands. The phylogeny presented here indicates that the ancestral sex expression in Leptinella is monoecy and that dioecy and paradioecy are derived conditions. High ploidy is especially common in the dioica-group, where dioecy is also common. However, the occurrence of a dioecious sex expression in tetraploid representatives of this group and of polyploidy in other clades that only exhibit monoecious or paradioecious conditions indicate that there is no consistent correlation between these two characters.     

Mediterranean diversification of the grass-feeding Anisopliina beetles (Scarabaeidae, Rutelinae, Anomalini) as inferred by bootstrap-averaged dispersal–vicariance analysis

Aim The circum‐Mediterranean region is one of the most complex regions of the Earth in terms of geography and natural history. The Old World species of the beetle subtribe Anisopliina (Scarabaeidae) feed almost exclusively on the pollen of grasses (Poaceae). Within this group, the ‘anisopliine clade’ forms a monophyletic group distributed mainly in the circum‐Mediterranean region. Here, we reconstruct the biogeographical history of the anisopliine beetles in relation to the diversification of grasses, and compare this reconstruction with previous hypotheses concerning the evolution of the Mediterranean fauna and with palaeogeographical accounts of the history of this region. Location The Mediterranean region, including North Africa, the Western Mediterranean, Balkans–Anatolia, Middle East and Caucasus. Methods Dispersal–vicariance analysis (diva ) was used to reconstruct ancestral distributions based on the morphological phylogeny and to infer the biogeographical processes that have shaped the observed distribution patterns. To account for phylogenetic uncertainty in the biogeographical reconstruction, we ran alternative ancestral distributions derived by diva over a sample of trees obtained by bootstrapping the original data set, reflecting the relative confidence of the ancestral areas on the various clades in the phylogeny. Results The Eastern Mediterranean region and the Caucasus are inferred as the ancestral area of most of the anisopliine lineages. The Eastern Mediterranean region is also reconstructed as the source area of the majority of dispersal events, in particular towards North Africa and the Western Mediterranean. The Iberian Peninsula is inferred as part of the ancestral distribution of the anisopliine clade but also as the setting of several independent colonization events via both the North African platform (Anthoplia) and a European dispersal route (Anisoplia). Main conclusions Our results confirm the role played by the Eastern Mediterranean as an evolutionary cradle of diversity for Mediterranean lineages. This can be explained by a recent and intense orogenic activity that might have promoted isolation and allopatric speciation within lineages. Both the Anomalini fossil record and the close association of anisopliine beetles with grasses suggest that the anisopliine clade originated in the Late Tertiary and that its spatial and temporal evolution within the Mediterranean Basin coincided with that of its major food source, the Mediterranean Poaceae.     

Dynamism and context‐dependency in diversification of the megadiverse plant genus Solanum (Solanaceae)

Explosive radiations—substantial increases in net species diversification—have been considered one of the most intriguing diversification patterns across the Tree of Life, but the subsequent change, movement, and extinction of the constituent lineages make radiations hard to discern or understand as geological time passes. We used the megadiverse angiosperm genus Solanum L. (Solanaceae), with ca. 1200 currently accepted species distributed worldwide in a wide array of habitats, to explore these patterns on a global scale. We synthesized phylogenetic and distributional data for this ongoing radiation to show how dispersal events and past climatic changes have interacted to shape diversification. We find that, despite the vast diversity of Solanum lineages in the Neotropics, lineages in the Old World are diversifying more rapidly. This recent increase in diversification coincides with a long‐distance dispersal event from the Neotropics to regions where major climatic changes were taking place. Two separate groups of Solanum have migrated and established in Australia, but only the arid‐adapted lineages underwent significant increases in diversification rate, as they were able to adapt to the continent's long‐term climatic trend towards seasonally dry and arid biomes (a pattern observed in the diversification of other arid‐adapted groups). Our findings provide a clear example of how successful colonization of new areas and niches can—but does not always—drive explosive diversifications.     

Patterns of long-distance dispersal in Tiquilia subg. Tiquilia (Boraginaceae): implications for the origins of amphitropical disjuncts and Galapagos Islands endemics

Plant biogeographers have long argued whether plant disjunctions result from vicariance or dispersal. One of the classic patterns of plant disjunction involves New World amphitropical disjuncts, as exemplified by Tiquilia subg. Tiquilia (Boraginaceae). Subgenus Tiquilia forms a heterogeneous group of ~20 species that is amphitropically distributed in the deserts of North and South America, with four taxa endemic to the Galápagos Islands. The current study reconstructs the biogeographic history of subg. Tiquilia in order to explore the origins of New World amphitropical disjunction and of Galápagos endemism. A strongly supported phylogeny of the subgenus is estimated using sequence data from matK, ndhF, rps16, ITS, and waxy. Biogeographic analyses using combined and individual marker data sets reveal a complex history of long-distance dispersal in subg. Tiquilia. Biogeographic reconstructions imply a North American origin of the subgenus and its three major lineages and require at least four long-distance dispersal events to explain its current distribution. The South American taxa of subg. Tiquilia result from three independent and nonsimultaneous colonization events, while the monophyly and continental origins of the Galápagos endemics are unresolved. This study contributes to a growing body of evidence that intercontinental dispersal has been more common than previously realized.     

Paleogene radiation of a plant pathogenic mushroom

Background

The global movement and speciation of fungal plant pathogens is important, especially because of the economic losses they cause and the ease with which they are able to spread across large areas. Understanding the biogeography and origin of these plant pathogens can provide insights regarding their dispersal and current day distribution. We tested the hypothesis of a Gondwanan origin of the plant pathogenic mushroom genus Armillaria and the currently accepted premise that vicariance accounts for the extant distribution of the species.

Methods

The phylogeny of a selection of Armillaria species was reconstructed based on Maximum Parsimony (MP), Maximum Likelihood (ML) and Bayesian Inference (BI). A timeline was then placed on the divergence of lineages using a Bayesian relaxed molecular clock approach.

Results

Phylogenetic analyses of sequenced data for three combined nuclear regions provided strong support for three major geographically defined clades: Holarctic, South American-Australasian and African. Molecular dating placed the initial radiation of the genus at 54 million years ago within the Early Paleogene, postdating the tectonic break-up of Gondwana.

Conclusions

The distribution of extant Armillaria species is the result of ancient long-distance dispersal rather than vicariance due to continental drift. As these finding are contrary to most prior vicariance hypotheses for fungi, our results highlight the important role of long-distance dispersal in the radiation of fungal pathogens from the Southern Hemisphere.     

Towards a phylogenetic framework for the evolution of shakes, rattles, and rolls in Myiarchus tyrant-flycatchers (Aves: Passeriformes: Tyrannidae)

A phylogeny of 19 of the 22 currently recognized species of Myiarchus tyrant-flycatchers is presented. It is based on 842bp of mitochondrial DNA (mtDNA) sequences from the ATPase subunit 8 and ATPase subunit 6 genes. Except for the morphologically distinct M. semirufus, mtDNAs of the remaining 18 species fall into either of two clades. One comprises predominantly Caribbean and Central and North American taxa (Clade I), and the other is of predominantly South American taxa (Clade II). The phylogeny is only very broadly concordant with some vocal characters and also with the limited morphological diversity for which the group is well known. Paraphyly in several species (M. swainsoni, M. tuberculifer, M. ferox, M. phaeocephalus, M. sagrae, M. stolidus) suggests that morphological evolution, albeit resulting in limited morphological diversity, has been more rapid than that of mtDNA, or that current taxonomy is faulty, or both. A South American origin for Myiarchus is likely. Dispersal and vicariance both appear to have been involved in generating the present-day distribution of some species. Relatively recent dispersal events out of South America are inferred to have brought species of Clades I and II into broad sympatry. Jamaica has been colonized independently at least twice by members of Clades I and II. The phylogeny brings a historical perspective that in turn suggests that ecological study of closely related species from within each major clade where they are sympatric will be especially rewarding.     

Molecular phylogeny and adaptive radiation of the endemic Hawaiian Plantago species (Plantaginaceae)

Insular oceanic islands provide excellent opportunities for the study of evolutionary processes and adaptive radiation. The Hawaiian Plantago radiation comprises six endemic taxa showing considerable inter- and intraspecific morphological and ecological diversity. The rDNA internal (ITS) and external (ETS) transcribed spacers and two recently described chloroplast spacers, ndhF-rpl32 and rpl32-trnL, were sequenced to study phylogenetic relationships within this morphologically complex group. Phylogenetic analysis provided strong evidence for the monophyly of Hawaiian Plantago, suggesting that the lineage arose from a single long-distance dispersal event. Inconsistencies between nuclear and chloroplast phylogenies suggest a history of hybridization. The basal, unresolved dichotomy of the combined phylogeny is consistent with rapid phenotypic diversification of the major lineages early in the history of this group. Speciation has largely occurred allopatrically, with divergence a result of intraisland ecological shifts between bog and woodland habitats and interisland dispersal events. Most interisland colonizations were from older to younger islands with initial colonization of Kaua'i. In our analysis, P. pachyphylla is paraphyletic and taxonomic separation of the distinct morphotypes of this species appears justified. Furthermore, the apparent hybrid ancestry and unique morphology and habitat of the endangered P. princeps var. longibracteata support its recognition at the specific rank.     

High Levels of Diversity Uncovered in a Widespread Nominal Taxon: Continental Phylogeography of the Neotropical Tree Frog Dendropsophus minutus

Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae) is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and the 16S rhibosomal gene (16S) for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km². One of them occupies an area of almost one million km² encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered.     

PHYLOGENY OF THE TRIBE CERATAPHIDINI (HOMOPTERA) AND THE EVOLUTION OF THE HORNED SOLDIER APHIDS

The horned soldier aphids of the Cerataphidini, unlike most social insects that reside in nests, live on the open surface of plants. The lack of a nest and other obvious ecological correlates makes it unclear why secondary-host soldiers might have evolved. Here I present a molecular phylogenetic analysis of 32 species of the Cerataphidini, including 10 species from the genera Ceratovacuna and Pseudoregma that produce horned soldiers. The phylogeny suggests that horned soldiers evolved once and were lost once or twice. Most horned soldiers are a morphologically specialized caste and two species that have unspecialized soldiers are independently derived from species with specialized castes. The genus Ceratovacuna appears to have undergone a relatively rapid radiation. Mapping secondary-host plants and geographic ranges onto the phylogeny suggests that bamboos were the ancestral secondary-host plants and that the Asian tropics and subtropics were the ancestral geographic regions for the genera Astegopteryx, Ceratoglyphina, Ceratovacuna Chaitoregma, and Pseudoregma and possibly for the entire tribe. There is evidence for vicariant events that separate the tropical and subtropical lineages in all of the major lineages of the tribe and for dispersal of some lineages. Based on these results, I present hypotheses for the causes and consequences of horned-soldier evolution.     

Major clades of parmelioid lichens (Parmeliaceae, Ascomycota) and the evolution of their morphological and chemical diversity

Parmelioid lichens comprise about 1500 species and have a worldwide distribution. Numerous species are widely distributed and well known, including important bioindicators for atmospheric pollution. The phylogeny and classification of parmelioid lichens has been a matter of debate for several decades. Previous studies using molecular data have helped to establish hypotheses of the phylogeny of certain clades within this group. In this study, we infer the phylogeny of major clades of parmelioid lichens using DNA sequence data from two nuclear loci and one mitochondrial locus from 145 specimens (117 species) that represent the morphological and chemical diversity in these taxa. Parmelioid lichens are not monophyletic; however, a core group is strongly supported as monophyletic, excluding Arctoparmelia and Melanelia s. str., and including Parmeliopsis and Parmelaria. Within this group, seven well-supported clades are found, but the relationships among them remain unresolved. Stochastic mapping on a MC/MCMC tree sampling was employed to infer the evolution of two morphological and two chemical traits believed to be important for the evolutionary success of these lichens, and have also been used as major characters for classification. The results suggest that these characters have been gained and lost multiple times during the diversification of parmelioid lichens.     

Delimitation of major lineages within Cuscuta subgenus Grammica (Convolvulaceae) using plastid and nuclear DNA sequences

Subgenus Grammica, the largest and most diverse group in the parasitic genus Cuscuta, includes 130 species distributed primarily throughout the New World, with Mexico as its center of diversity. To circumscribe the subgenus and assess the relationships among its major lineages, we conducted the first phylogenetic study of Grammica using plastid trnL-F and nrITS sequences from a wide taxonomic sampling covering its morphological, physiological, and geographical diversity. With the exception of one species belonging elsewhere, the subgenus was found to be monophyletic. The results further indicate the presence of 15 well-supported major clades within Grammica. Some of those lineages correspond partially to earlier taxonomic treatments, but the majority of groups are identified in this study for the first time. The backbone relationships among major clades, however, remain weakly supported or unresolved in some cases. The phylogenetic results indicate that the fruit dehiscence character is homoplastic, thus compromising its value as a major taxonomic and evolutionary feature. While several striking cases of long-distance dispersal are inferred, vicariance emerges as the most dominant biogeographical pattern for Cuscuta. Species placed within one of the clades with a predominantly South American distribution are hypothesized to have substantially altered plastid genomes.     

Cape diversification and repeated out-of-southern-Africa dispersal in paper daisies (Asteraceae-Gnaphalieae)

The large daisy tribe Gnaphalieae occurs in extra-tropical habitats worldwide, but is most diverse in southern Africa and in Australia. We explore the age and evolutionary history of the tribe by means of a phylogenetic hypothesis based on Bayesian analysis of plastid and nuclear DNA sequences, maximum likelihood reconstruction of ancestral areas, and relaxed Bayesian dating. Early diversification occurred in southern Africa in the Eocene-Oligocene, resulting in a grade of mostly Cape-centred lineages which subsequently began speciating in the Miocene, consistent with diversification times for many Cape groups. Gnaphalieae from other geographic regions are embedded within a southern African paraphylum, indicating multiple dispersals out of southern Africa since the Oligocene to Miocene which established the tribe in the rest of the world. Colonisation of Australia via direct long-distance trans-oceanic dispersal in the Miocene resulted in the radiation which produced the Australasian gnaphalioid flora. The similarly diverse regional gnaphalioid floras of Australasia and southern Africa thus exhibit very different temporal species accumulation histories. An examination of the timing and direction of trans-Indian Ocean dispersal events in other angiosperms suggests a role for the West Wind Drift in long-distance dispersal eastwards from southern Africa.     

Ancient forest fragmentation or recent radiation? Testing refugial speciation models in chameleons within an African biodiversity hotspot

Aim East Africa is one of the most biologically diverse regions, especially in terms of endemism and species richness. Hypotheses put forward to explain this high diversity invoke a role for forest refugia through: (1) accumulation of new species due to radiation within refugial habitats, or (2) retention of older palaeoendemic species in stable refugia. We tested these alternative hypotheses using data for a diverse genus of East African forest chameleons, Kinyongia. Location East Africa. Methods We constructed a dated phylogeny for Kinyongia using one nuclear and two mitochondrial markers. We identified areas of high phylogenetic diversity (PD) and evolutionary diversity (ED), and mapped ancestral areas to ascertain whether lineage diversification could best be explained by vicariance or dispersal. Results Vicariance best explains the present biogeographic patterns, with divergence between three major Kinyongia clades (Albertine Rift, southern Eastern Arc, northern Eastern Arc) in the early Miocene/Oligocene (> 20 Ma). Lineage diversification within these clades pre‐dates the Pliocene (> 6 Ma). These dates are much older than the Plio‐Pleistocene climatic shifts associated with cladogenesis in other East African taxa (e.g. birds), and instead point to a scenario whereby palaeoendemics are retained in refugia, rather than more recent radiations within refugia. Estimates of PD show that diversity was highest in the Uluguru, Nguru and East Usambara Mountains and several lineages (from Mount Kenya, South Pare and the Uluguru Mountains) stand out as being evolutionarily distinct as a result of isolation in forest refugia. PD was lower than expected by chance, suggesting that the phylogenetic signal is influenced by an unusually low number of extant lineages with long branch lengths, which is probably due to the retention of palaeoendemic lineages. Main conclusions The biogeographic patterns associated with Kinyongia are the result of long evolutionary histories in isolation. The phylogeny is dominated by ancient lineages whose origins date back to the early Miocene/Oligocene as a result of continental wide forest fragmentation and contraction due to long term climatic changes in Africa. The maintenance of palaeoendemic lineages in refugia has contributed substantially to the remarkably high biodiversity of East Africa.     

Phylogeny, divergence times, and historical biogeography of New World Dryopteris (Dryopteridaceae)

? Premise of the study: Dryopteris is a large, cosmopolitan fern genus ideal for addressing questions about diversification, biogeography, hybridization, and polyploidy, which have historically been understudied in ferns. We constructed a highly resolved, well-supported phylogeny for New World Dryopteris and used it to investigate biogeographic patterns and divergence times. ? Methods: We analyzed relationships among 97 species of Dryopteris, including taxa from all major biogeographic regions, with analyses based on 5699 aligned nucleotides from seven plastid loci. Phylogenetic analyses used maximum parsimony, maximum likelihood, and Bayesian inference. We conducted divergence time analyses using BEAST and biogeographic analyses using maximum parsimony, maximum likelihood, Bayesian, and S-DIVA approaches. We explored the monophyly of subgenera and sections in the most recent generic classification and of geographic groups of taxa using Templeton tests. ? Key results: The genus Dryopteris arose ca. 42 million years ago (Ma). Most of the Central and South American species form a well-supported clade which arose 32 Ma, but the remaining New World species are the result of multiple, independent dispersal and vicariance events involving Asia, Europe, and Africa over the last 15 Myr. We identified six long-distance dispersal events and three vicariance events in the immediate ancestry of New World species; reconstructions for another four lineages were ambiguous. ? Conclusions: New World Dryopteris are not monophyletic; vicariance has dominated the history of the North American species, while long-distance dispersal prevails in the Central and South American species, a pattern not previously seen in plants.     

Fungal radiation in the Cape Floristic Region: an analysis based on Gondwanamyces and Ophiostoma

The Cape Floristic Region (CFR) displays high levels of plant diversity and endemism, and has received focused botanical systematic attention. In contrast, fungal diversity patterns and co-evolutionary processes in this region have barely been investigated. Here we reconstruct molecular phylogenies using the ITS and beta-tubulin gene regions of the ophiostomatoid fungi Gondwanamyces and Ophiostoma associated with southern African Protea species. Results indicate that they evolved in close association with Protea. In contrast to Protea, Ophiostoma species migrated to the CFR from tropical and subtropical Africa, where they underwent subsequent radiation. In both Gondwanamyces and Ophiostoma vector arthropods probably facilitated long-distance migration and shorter-distance dispersal. Although ecological parameters shaped most associations between ophiostomatoid fungi and Protea, there is congruence between fungal-host-associations and the systematic classification of Protea. These results confirm that the entire biotic environment must be considered in order to understand diversity and evolution in the CFR as a whole.     

Molecular and morphological phylogeny of hooded shrimps, genera Betaeus and Betaeopsis (Decapoda, Alpheidae): testing the center of origin biogeographic model and evolution of life history traits

The phylogenetic relationships of the alpheid shrimp genera Betaeus (Dana, 1852) (15 species) and Betaeopsis (Yaldwyn, 1971) (three species), collectively known as hooded shrimps, are analyzed with morphological, molecular (16S and H3) and combined "total evidence" (morphology+DNA) datasets. The tree topology resulting from morphological and combined analyses places Betaeus jucundus as sister to all the remaining species of Betaeus and Betaeopsis, rendering Betaeus paraphyletic. On the other hand, Betaeopsis is recovered as monophyletic. Betaeus australis is positioned as sister to the remaining species of Betaeus s. str. (excluding B. jucundus), which is composed of three well-supported and resolved clades. Mapping of biogeographic traits on the combined tree suggests at least two possible historic scenarios. In the first scenario, the North-East Pacific harboring the highest diversity of hooded shrimps (seven species of Betaeus), acted as the "center of origin", where species appeared, matured and eventually migrated toward peripheral regions. In the second scenario, Betaeus+Betaeopsis originated in the southern Indo-West Pacific and subsequently colonized the North-East Pacific, where a major radiation involving dispersal/vicariance events took place. The mapping of life history traits (symbiosis vs. free living and gregariousness vs. single/pair living) in the combined tree suggests (1) that different types of symbioses with dissimilar host organisms (sea urchins, abalones, other decapods, spoon worms) evolved independently more than once in the group (in B. jucundus and in various lineages of Betaeus s. str.), and (2) that gregariousness was ancestral in the Betaeus s. str. -Betaeopsis clade and later shifted toward single/pair living in several lineages.