Parsimony Approaches Research Articles

Origins of the Endemic Scaly Tree Ferns on the Galápagos and Cocos Islands

Premise of research. Successful long-distance dispersal is rarely observed in scaly tree ferns (Cyatheaceae). Nevertheless, recent molecular evidence has suggested that the four endemic scaly tree ferns on the Galápagos Archipelago (Cyathea weatherbyana) and Cocos Island (Cyathea alfonsiana, Cyathea nesiotica, and Cyathea notabilis), two oceanic island groups west of Central and northern South America, probably each originated from different mainland America ancestors. However, the phylogenetic relationships inferred among these endemics and their mainland relatives have been unclear. This study is aimed at better resolving the relationships and tracing the origins of these island endemics.Methodology. Five plastid regions from 35 Cyathea species were analyzed to reconstruct phylogenetic relationships using parsimony, likelihood, and Bayesian approaches. We also estimated divergence times of these species, and our chronogram was used to reconstruct their biogeographical range history.Pivotal results. Our well-resolved phylogenetic tree of Cyathea, which is in agreement with previous studies, shows that when the four Galápagos and Cocos endemics are included, they each belong to separate subclades. Our biogeographical study suggests that the four endemics originated from independent colonization events from mainland America and that there was no dispersal of Cyathea between the island groups. We reveal more detailed relationships among the endemics and their respective close mainland relatives; some of these relationships differ from previous studies. Our findings are corroborated by new morphological data from ongoing stem anatomy studies.Conclusions. The four scaly tree ferns endemic to the Galápagos and Cocos Islands each did indeed originate as independent colonization events from separate sources in mainland America, and their closest relatives are identified here.

Biogeography and evolution ofDolichandra(Bignonieae, Bignoniaceae)

Little information on evolutionary relationships of Neotropical organisms or on the factors that have shaped the diversity currently encountered in this region is available. However, it is clear that biotic interactions and abiotic aspects have played important roles for species diversification in the region. This study focuses on Dolichandra (Bignonieae, Bignoniaceae), a clade of Neotropical lianas that is distributed broadly across different habitats and with diverse pollination and dispersal systems. We used sequences from two plastid DNA markers (ndhF and rpl32-trnL) and one nuclear gene (PepC) to infer phylogenetic relationships in Dolichandra using parsimony and Bayesian approaches. We then used this phylogenetic framework as basis to study the biogeographic history, reconstruct the evolution of morphological characters and test the impact of morphology and environment on the diversification of the genus. More specifically, we: (1) time-calibrate the phylogenetic tree of Dolichandra; (2) estimate the ancestral areas of the various lineages; (3) estimate the ancestral states of discrete and continuous morphological traits; (4) test for phylogenetic signal in environmental and phenotypic data; and (5) test whether morphological characters and/or niche evolution are correlated with cladogenesis. All Dolichandra spp. are monophyletic in the combined molecular phylogeny; relationships among species are generally well resolved, although poorly supported in some instances. The genus is inferred to have originated 36.43–26.23 Mya, possibly in eastern South America. Ancestral state reconstructions of continuous and discrete floral characters inferred a mixed morphology as the ancestral condition for the group. Phylogenetic signal differed between perianth and sexual whorls and gradual evolution was recovered for all traits except style length and anther length. Environmental variables showed no phylogenetic signal and a pattern of variation that was not correlated with branch length, suggesting that environmental transitions were concomitant with speciation. Dispersal is inferred to be the main driver of the differential distribution observed among species. In addition, climatic preferences and floral characters seem to have been important reproductive barriers in Dolichandra. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, ●●, ●●–●●.

Improving intraspecific allele networks inferred by maximum parsimony

Summary Allele (or haplotype) networks are often used in phylogeographic studies to display genetic variation within a species or a group of closely related species. A global maximum parsimony approach to infer allele networks, arguably the method of choice to display genetic variation at the intraspecific level, consists in inferring all most parsimonious trees from a DNA sequence alignment and combining the corresponding phylograms into a single graph. However, it has been suggested that, while classic phylogenetic programs generate a single phylogram per most parsimonious tree, deriving all possible phylograms from them would allow identifying additional most parsimonious paths among alleles, thereby improving this network inference method. We test this prediction by analysing both simulated and empirical DNA sequence alignments. For this purpose, a computer program, CPN, was developed to implement the entire procedure, starting with a set of most parsimonious trees and combining all derived phylograms into a network. We show that including all possible most parsimonious phylograms indeed often results in finding additional most parsimonious paths in the network graph, thereby improving the search for a global maximum parsimony solution. We highly recommend the use of this approach in future phylogeographic studies, to ensure that all most parsimonious paths are included in the allele network, instead of an arbitrarily selected subset of those.

Molecular phylogenetics of the species-rich angiosperm genus Goniothalamus (Annonaceae) inferred from nine chloroplast DNA regions: Synapomorphies and putative correlated evolutionary changes in fruit and seed morphology

A phylogenetic study of the genus Goniothalamus (Annonaceae) is presented using maximum parsimony, maximum likelihood and Bayesian approaches, with 65 species sampled (48.5% of the genus) based on sequences of nine chloroplast DNA regions (11,214 aligned positions). The resultant phylogeny clearly indicates that Goniothalamus is monophyletic. Preliminary research initially focused on identifying synapomorphies and estimating the phylogenetic signal of selected morphological characters based on parsimony and likelihood ancestral character state reconstructions. This prescreening of characters enabled 40 to be selected for further study, and of these 15 are shown here to demonstrate significant phylogenetic signal and to provide clear synapomorphies for several infrageneric clades. Although floral structure in Goniothalamus is comparatively uniform, suggesting a common basic pattern of pollination ecology, fruit and seed morphology in the genus is very diverse and is presumably associated with different patterns of frugivory. The present study assesses correlations amongst fruit and seed characters which are putatively of functional importance with regard to frugivory and dispersal. One-way phylogenetic ANOVA indicates significant phylogenetically independent correlation between the following fruit and seed characters: fruits borne on older branches and/or on the main trunk have larger monocarps than fruits borne on young branches; and monocarps that contain seeds with a hairy testa are larger than those with glabrous seeds. We discuss fruit morphologies and potential explanations for the inferred correlations, and suggest that they may be the result of adaptation to different frugivores (birds, larger non-volant animal and primate seed dispersers, respectively).

Adaptive radiations in butterflies: evolutionary history of the genusErebia(Nymphalidae: Satyrinae)

We studied the speciose butterfly genus Erebia by reconstructing its phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification for its lineages and employed a biogeographical analysis in order to reconstruct its evolutionary history. DNA sequence data from one mitochondrial gene and three nuclear genes were analyzed for a total of 74 species in Erebia. The estimated dates of origin and diversification for clades, in combination with a biogeographical analysis, suggest that the genus originated in Asian Russia and started its diversification process around 23 Myr. An important event was the dispersal of a lineage from Asia to Western Europe between 23 and 17 Myr, which allowed the radiation of most of species in the genus. The diversification pattern is consistent with a model of diversity limited by clade richness, which implies an early rapid diversification followed by deceleration due to a decrease in speciation. We argue that these characteristics of the evolutionary history of Erebia are consistent with a density-dependent scenario, with species radiation limited by filling of niche space and reduced resources. We found that the Boeberia parmenio appears strongly supported in the genus Erebia and therefore we place Boeberia Prout, 1901 as a junior synonym of Erebia Dalman, 1816 (syn. nov.). (Less)

Phylogeny and classification of the East Asian Amitostigma alliance (Orchidaceae: Orchideae) based on six DNA markers.

BackgroundTribe Orchideae dominates the orchid flora of the temperate Northern Hemisphere but its representatives in East Asia had been subject to less intensive phylogenetic study than those in Eurasia and North America. Although this situation was improved recently by the molecular phylogenetic study of Jin et al., comparatively few species were analyzed from the species-rich and taxonomically controversial East Asian Amitostigma alliance. Here, we present a framework nrITS tree of 235 accessions of Orchideae plus an in-depth analysis of 110 representative accessions, encompassing most widely recognized species within the alliance, to elucidate their relationships.ResultsWe used parsimony, likelihood and Bayesian approaches to generate trees from data for two nuclear (nrITS, low-copy Xdh) and four chloroplast (matK, psbA-trnH, trnL-F, trnS-trnG) markers. Nuclear and plastid data were analyzed separately due to a few hard incongruences that most likely reflect chloroplast capture. Our results suggest key phylogenetic placements for Sirindhornia and Brachycorythis, and confirm previous assertions that the Amitostigma alliance is monophyletic and sister to the Eurasian plus European clades of subtribe Orchidinae. Seven robust clades are evident within the alliance, but none corresponds precisely with any of the traditional genera; the smaller and more morphologically distinct genera Tsaiorchis, Hemipilia, Neottianthe and Hemipiliopsis are monophyletic but each is nested within a polyphyletic plexus of species attributed to either Ponerorchis or the most plesiomorphic genus, Amitostigma. Two early-divergent clades that escaped analysis by Jin et al. undermine their attempt to circumscribe an expanded monophyletic genus Ponerorchis.ConclusionsWe provide a new framework on the complex phylogenetic relationships between Amitostigma and other genera traditionally included in its alliance; based on which, we combine the entire Amitostigma alliance into a morphologically and molecularly circumscribed Amitostigma sensu latissimo that also contains seven molecularly circumscribed sections. Our molecular trees imply unusually high levels of morphological homoplasy, but these will need to be quantified via a future group-wide review of the alliance based on living plants if morphology is to be fully integrated into our classification.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-015-0376-3) contains supplementary material, which is available to authorized users.

Phylogeographic evidence for a Florida panhandle-peninsula discontinuity in the distribution ofMelitara prodenialisWalker (Lepidoptera: Pyralidae), a native cactus-boring moth

Insects are highly underrepresented in the phylogeographic literature of the coastal plain region of the southeastern U.S., but they may contribute much to understanding the phylogeographic history of the area. The present study uses Melitara prodenialis Walker, a cactus-boring moth, to test two alternative hypotheses: Pleistocene changes in environment and coastline associated with population geographic change resulted in (i) a homogeneous Florida, USA, population of M. prodenialis or (ii) isolated subpopulations that gave rise to genetic divergence between regions. Melitara prodenialis larvae were collected from 23 sites (n = 42 larvae sampled). For each larva, a 791 bp sequence of the COI mitochondrial gene was sequenced. Bayesian and parsimony approaches were used to investigate relationships among haplotypes. Phylogeographic and demographic analyses were conducted to identify geographic patterns in haplotype diversity distribution and infer population dynamics over time. Bioclim climate variables from the last interglacial period and the present were used to assess the potential contribution of environmental conditions to phylogeographic patterns observed. Melitara prodenialis populations in the Florida panhandle and peninsula are distinct, and the geographic segregation between these regions is correlated with current and historic climate patterns. Results suggest that populations of M. prodenialis in the Florida peninsula have more recently expanded than those in the panhandle. These findings are consistent with M. prodenialis populations changing in size and distribution following land area and climatic shifts associated with North American cycles of glaciation, with panhandle and peninsula populations remaining segregated over the relevant timeframes.

Molecular phylogeny confirms the placement of enigmatic Stachys persepolitana in Lamium (Lamiaceae; subfam. Lamioideae)

The main purpose of this study was to test the hypothesis that Stachys persepolitana is extraneous in Stachys (tribe Stachydeae, subfam. Lamioideae, Lamiaceae) and instead belongs to the genus Lamium (Lamieae, Lamioideae). We investigated the phylogenetic position of S. persepolitana using plastid (rps16 intron, trnL-F and matK regions) and nuclear (nrITS) DNA sequence data with both parsimony and Bayesian phylogenetic approaches. Plastid and nuclear data strongly support that S. persepolitana is extraneous in Stachys and belongs in fact to the genus Lamium. Morphological characters also corroborate its placement in Lamium. Most of the morphological features used to distinguish S. persepolitana from the rest of Stachys fit with Lamium. Anterior pair of stamens bending outward after pollination, anthers hairy and mericarps triquetrous are the most important characters correlating S. persepolitana to Lamium.

Total evidence analysis of the phylogenetic relationships of Lycosoidea spiders (Araneae, Entelegynae)

Phylogenetic relationships within the superfamily Lycosoidea are investigated through the coding and analysis of character data derived from morphology, behaviour and DNA sequences. In total, 61 terminal taxa were studied, representing most of the major groups of the RTA-clade (i.e. spiders that have a retrolateral tibial apophysis on the male palp). Parsimony and model-based approaches were used, and several support values, partitions and implied weighting schemes were explored to assess clade stability. The morphological–behavioural matrix comprised 96 characters, and four gene fragments were used: 28S (~737 base pairs), actin (~371 base pairs), COI (~630 base pairs) and H3 (~354 base pairs). Major conclusions of the phylogenetic analysis include: the concept of Lycosoidea is restricted to seven families: Lycosidae, Pisauridae, Ctenidae, Psechridae, Thomisidae, Oxyopidae (but Ctenidae and Pisauridae are not monophyletic) and also Trechaleidae (not included in the analysis); the monophyly of the ‘Oval Calamistrum clade’ (OC-clade) appears to be unequivocal, with high support, and encompassing the Lycosoidea plus the relimited Zoropsidae and the proposed new family Udubidae (fam. nov.); Zoropsidae is considered as senior synonym of Tengellidae and Zorocratidae (syn. nov.); Viridasiinae (rank nov.) is raised from subfamily to family rank, excluded from the Ctenidae and placed in Dionycha. Our quantitative phylogenetic analysis confirms the synonymy of Halidae with Pisauridae. The grate-shaped tapetum appears independently at least three times and has a complex evolutionary history, with several reversions.

Characterization of Hawaiian freshwater and terrestrial cyanobacteria reveals high diversity and numerous putative endemics

SummaryFifty samples of cyanobacteria were collected and characterized as part of the Hawaiian Freshwater Algal Biodiversity Survey. Fifty‐two percent of the samples originated from Oahu, while the remainder were collected from Kauai (14%), Maui (20%) and Hawaii (14%). A diversity of habitats (e.g. streams, wet walls, taro fields, terrestrial areas and ditches) was represented by the collection sites, which is reflective of the abundance of suitable non‐marine algal substrata in these isolated, humid, subtropical islands. Most samples were isolated and cultured for observation of morphological features, and all were sequenced for both the Universal Plastid Amplicon (UPA) marker (partial 23S rRNA) and 16S rRNA gene. Alignments of both markers (separately and concatenated) with additional GenBank sequences for phylogenetic representation were analyzed using Maximum Likelihood, Bayesian and Maximum Parsimony approaches. Nodal support was highest for the concatenated UPA+16S rRNA gene alignment, and phylogenetic analyses indicated a monophyletic Nostochophycidae, and monophyly, although with low support, for the Oscillatoriophycidae and Synechococcophycidae. A conservative estimate is that 11 of the taxa are putative endemics to the Hawaiian Islands, further highlighting the uniqueness of this isolated and understudied flora, and the potential for discovery of novel taxa through taxon‐focused biodiversity surveys.

Mitochondrial phylogeny shows multiple independent ecological transitions and northern dispersion despite of Pleistocene glaciations in meadow and steppe vipers (Vipera ursinii and Vipera renardi)

The phylogeny and historical demography of small Eurasian vipers of the Vipera ursinii and V. renardi complexes were studied using mitochondrial DNA sequences analysed with Bayesian inference, Maximum Likelihood and Maximum Parsimony approaches, and mismatch distributions. Diversification in the group resulted from an initial dispersion in the later Pliocene – Pleistocene in two directions: north-westwards via the Balkans (V. ursinii complex) and north-eastwards from Asia Minor via the Caucasus (V. renardi complex). An independent, comparatively recent transition occurred from montane habitats to lowland grasslands in different mitochondrial lineages during the Late Pleistocene, when representatives of the both complexes had reached lowland steppes to the north. Effective population size showed clear signs of rapid growth in eastern V. renardi, triggered by colonization of vast lowland steppes, but in western V. ursinii complex grew during the Last Glaciation and experienced stabilization in Holocene. Expansion and population growth in lowland lineages of V. renardi was not strongly affected by Pleistocene climatic oscillations, when cold, dry conditions could have favoured species living in open grasslands. The high diversity of closely related haplotypes in the Caucasus and Tien-Shan could have resulted from repetitive expansion-constriction-isolation events in montane regions during Pleistocene climate fluctuations. The mitochondrial phylogeny pattern conflicts with the current taxonomy.

Integrative taxonomy of the stunt nematodes of the generaBitylenchusandTylenchorhynchus(Nematoda, Telotylenchidae) with description of two new species and a molecular phylogeny

Stunt nematodes are characterized by phenotypic plasticity, with overlapping morphology and morphometry leading to potential misidentification. Consequently, the application of integrative taxonomic approaches is useful to species delimitation based on a combination of different perspectives, e.g. morphology and DNA sequences. We conducted nematode surveys in cultivated and natural environments in Spain and the USA, from which we identified 18 known species of the family Telotylenchidae and two new taxa within the studied samples. These species were morphologically, morphometrically, and molecularly characterized. The results of light and scanning electron microscopic observations, and molecular and phylogenetic analysis also allowed two new species to be distinguished, described herein as Bitylenchus hispaniensis sp. nov. and Tylenchorhynchus mediterraneus sp. nov. The phylogenetic analysis was carried out using molecular data from nuclear ribosomal DNA genes [D2–D3 expansion segments of the large ribosomal subunit (28S), internal transcribed spacer (ITS), and partial small ribosomal subunit (18S)]. We also provide here a test of alternative hypotheses that confirms the monophyly of both Tylenchorhynchus and Bitylenchus sensu Siddiqi's classification but does not support Fortuner & Luc's conceptual view of Tylenchorhynchus as a large genus. Ancestral state reconstructions of several diagnostic morphological characters using a maximum parsimony approach showed congruence in morphological and molecular evolution for stylet knob inclination and tail tip annulation. Our analysis emphasizes some of the problems related to the taxonomy and phylogeny of nematodes of Telotylenchinae. © 2014 The Linnean Society of London

Concatabominations: identifying unstable taxa in morphological phylogenetics using a heuristic extension to safe taxonomic reduction.

For a variety of reasons, some phylogenetic data sets are replete with missing entries. Attitudes toward abundant missing data, specifically concerns over its potential to mislead or confound phylogenetic inferences, are varied. Thus, there is a current debate on the impact of missing entries upon the accuracy of phylogenetic inferences (Wiens 2006; Lemmon et al. 2009; Philippe et al. 2011; Wiens and Morrill 2011; Roure et al. 2013). Perhaps less controversial is that individual taxa may sometimes be relatively phylogenetically unstable by virtue of limited data and extensive missing data (e.g., Wilkinson 1996; Sanderson and Shaffer 2002; Wiens 2003; Wilkinson 2003). Wilkinson (1995) developed an approach for diagnosing taxon instability due to missing data a priori termed safe taxonomic reduction (STR). STR allows the identification of “rogue” taxa that can be removed from a data set safe in the knowledge that their removal will not impact upon the interrelationships that will be inferred among the remaining taxa under the parsimony criterion. The potential benefits of such deletion are reductions in numbers of optimal trees and run times and better resolved consensus summaries. STR has been fairly widely used, mainly by paleontologists confronted with relatively incomplete fossil taxa (see Anquetin 2012; Graf 2012; McDonald 2012; for some recent examples), and also in the context of the matrix representation with parsimony (Baum 1992; Ragan 1992) approach to supertree construction (e.g., Cardillo et al. 2004). Nonetheless STR is not always as effective as one might hope (e.g., Mannion et al. 2013). Here, we present a simple heuristic method for identifying potentially unstable taxa that may be useful in cases where STR does not succeed in ameliorating all the problems caused by missing data. We illustrate the approach through application to the saurischian data of Gauthier (1986), which was previously used to illustrate STR and thus is particularly appropriate for demonstrating the ability of the new method to achieve more than STR alone.

Systematic implications of seed morphological diversity in Portulacaceae (Caryophyllales)

The Portulacaceae are a monogeneric family with around 100 species distributed around the world. Seed morphology in the group is diverse, but its systematic significance is controversial, and its diversification patterns are unknown. In this study, the seed morphology and size of 63 samples representing 49 species, nine varieties, and two cultivars are evaluated under a phylogenetic framework. Eight seed features (including size) and DNA sequences were analyzed with parsimony and Bayesian methods and seed diversification patterns were estimated using ancestral character reconstruction under a parsimony approach. Analyses of the seed features retrieved an unresolved phylogeny, contrary to the phylogenetic estimate of the DNA data that was consistent with the clades and subclades obtained in previous studies. The analyses of a combined data matrix of seed features and DNA sequence data did not improve nodal support for the relationships within Portulacaceae. Although the hypothesis testing procedures could not reject the monophyly of major clades within Portulacaceae, ancestral character reconstruction analyses showed that the seed features are homoplasious and do not represent synapomorphies for those clades. Some character states were predominantly present in one clade and were rarely found in others. Seed size seemed to be relatively constant throughout the evolutionary history of Portulacaceae (<0.85 mm long), with multiple independent events of size increase. Although seed features do not reflect the evolutionary history of Portulacaceae, they still have a high taxonomic value, especially when used along with other features.

A phylogeny of the Gochnatieae: Understanding a critically placed tribe in the Compositae

AbstractSubfamily Gochnatioideae is the sister group of ∼96% of the species in Compositae (Asteraceae). It is of particular interest not only because of its position in the phylogeny, but also because, in recent molecular studies, the node it occupies is not strongly supported making difficult any inferences on the direction of character evolution in the family. The recognition of tribe Gochnatieae was one of the results of a comprehensive molecular analysis of the family that showed the traditional circumscription of the Mutisieae to be non–monophyletic. The four genera of Gochnatieae (Cnicothamnus, Cyclolepis, Gochnatia, Richterago) were defined by the presence of apiculate anther appendages and dorsally smooth style branches. Gochnatia, which contained about 70 species, was the largest and most complex genus and in the last decade some of its sections have been moved (or returned) to the rank of genus. This study includes a large selection of potential outgroups and over 60% of all species in the tribe, including all the genera and all but one of the sections of Gochnatia, to examine evolutionary relationships among the taxa. Both cpDNA and nrDNA were used in a phylogenetic analysis using parsimony, likelihood, and Bayesian approaches. The results suggest a non–monophyletic Gochnatia that is here resolved by the recognition of segregate genera. Morphological characters support these new genera and allow the adoption of a new classification for the Gochnatieae. A biogeographic analysis shows a possible southern South American/Andean origin followed by movement in three directions: into the Central Andes, into central and northern Brazil, and into Mexico and the Caribbean. The dating analysis gives an age of the split of the core Gochnatieae from the Wunderlichieae–Cyclolepis clade, and hence the age of the tribe, of 36–45 Ma and an age of 23–25 Ma for the first split within the core Gochnatieae (Andean vs. Brazil–Mexico–Caribbean). Cnicothamnus remains in Gochnatieae but Cyclolepis is designated incertae sedis.

&lt;span lang="EN-GB"&gt;Frullania subarctica—&lt;/span&gt;&lt;span lang="EN-GB"&gt;a new species of the Frullania tamarisci complex (Frullaniaceae, Marchantiophyta)&lt;/span&gt;

This study tests the phylogenetic affinity and clarifies the taxonomy of Frullania tamarisci s. l. in Russia and adjacent areas based on critical morphological reinvestigation and DNA analyses. More than 100 accessions of F. tamarisci s. l. from the collections of KPABG, VBGI and UBC were studied morphologically, and the nrITS1-5.8S-ITS2 and trnL–trnF cpDNA loci of sixteen accessions were sequenced. Molecular data were combined with accessions from GenBank and phylogenetic estimations by maximum parsimony, maximum likelihood and Bayesian approaches were performed. The tree topologies obtained were congruent and resolved the specimens previously referred to F. nisquallensis from Russian North in a clade together with an accession from Alaska. This clade is only distantly related to European F. tamarisci s. str. and temperate western North American F. nisquallensis. Taking into account the morphological differences, we describe a new species Frullania subarctica Vilnet, Borovich. &amp; Bakalin sp. nov. The species status for F. appendiculata occurring mainly in temperate East Asia was supported by molecular evidence, based on specimens from the Primorsky Territory of Russia. Populations of F. tamarisci s. str. from the Russian North West and the Caucasus Mountains are quite similar to those from European countries both morphologically and molecularly.

Molecular phylogeny and biogeography of the fern genus Pteris (Pteridaceae).

Pteris (Pteridaceae), comprising over 250 species, had been thought to be a monophyletic genus until the three monotypic genera Neurocallis, Ochropteris and Platyzoma were included. However, the relationships between the type species of the genus Pteris, P. longifolia, and other species are still unknown. Furthermore, several infrageneric morphological classifications have been proposed, but are debated. To date, no worldwide phylogenetic hypothesis has been proposed for the genus, and no comprehensive biogeographical history of Pteris, crucial to understanding its cosmopolitan distribution, has been presented. A molecular phylogeny of Pteris is presented for 135 species, based on cpDNA rbcL and matK and using maximum parsimony, maximum likelihood and Bayesian inference approaches. The inferred phylogeny was used to assess the biogeographical history of Pteris and to reconstruct the evolution of one ecological and four morphological characters commonly used for infrageneric classifications. The monophyly of Pteris remains uncertain, especially regarding the relationship of Pteris with Actiniopteris + Onychium and Platyzoma. Pteris comprises 11 clades supported by combinations of ecological and morphological character states, but none of the characters used in previous classifications were found to be exclusive synapomorphies. The results indicate that Pteris diversified around 47 million years ago, and when species colonized new geographical areas they generated new lineages, which are associated with morphological character transitions. This first phylogeny of Pteris on a global scale and including more than half of the diversity of the genus should contribute to a new, more reliable infrageneric classification of Pteris, based not only on a few morphological characters but also on ecological traits and geographical distribution. The inferred biogeographical history highlights long-distance dispersal as a major process shaping the worldwide distribution of the species. Colonization of different niches was followed by subsequent morphological diversification. Dispersal events followed by allopatric and parapatric speciation contribute to the species diversity of Pteris.

Evolution and Development of Tendrils in Bignonieae (Lamiales, Bignoniaceae)1

Abstract The tribe Bignonieae includes all Neotropical lianescent Bignoniaceae. The leaves of Bignonieae are generally 2- or 3-foliolate, with terminal leaflets modified into a tendril. These tendrils have varied morphologies and are thought to have been involved in the diversification of Bignonieae. Little, however, is still known about the biology and evolution of tendrils. This study investigated the evolution and development of tendril types in Bignonieae in order to further understand how changes in leaf morphogenesis led to current patterns of variation in tendril morphology. For that, we investigated the ontogeny of 11 species representing a wide diversity of tendril types (i.e., simple, trifid, and multifid) and used a recently published phylogeny of Bignonieae as the basis to reconstruct patterns of evolution for tendril types. For those analyses, we used maximum likelihood (ML) and maximum parsimony (MP) approaches, with both ACCTRAN and DELTRAN optimization schemes implemented in the latter. An...

A new genus of miniature cynolebiasine from the Atlantic Forest and alternative biogeographical explanations for seasonal killifish distribution patterns in South America (Cyprinodontiformes: Rivulidae)

The analysis of 78 morphological characters for 16 species representing all the lineages of the tribe Cynopoecilini and three out-groups, indicates that the incertae sedis miniature species ‘Leptolebias’ leitaoi Cruz &amp; Peixoto is the sister group of a clade comprising the genera Leptolebias, Campellolebias, and Cynopoecilus, consequently recognised as the only member of a new genus. Mucurilebias gen. nov. is diagnosed by seven autapomorphies: eye occupying great part of head side, low number of caudal-fin rays (21), distal portion of epural much broader than distal portion of parhypural, an oblique red bar through opercle in both sexes, isthmus bright red in males, a white stripe on the distal margin of the dorsal fin in males, and a red stripe on the distal margin of the anal fin in males. Mucurilebias leitaoi is an endangered seasonal species endemic to the Mucuri river basin. The biogeographical analysis of genera of the subfamily Cynolebiasinae using a dispersal-vicariance, event-based parsimony approach indicates that distribution of South American killifishes may be broadly shaped by dispersal events. The analysis supports south-eastern Brazilian coastal plains as the centre of dispersal for cynolebiasine killifishes. Alternative biogeographical explanations are compared and possible dispersal routes and means of dispersal are discussed.

Two new species of the liverwort genus Hygrobiella Spruce (Marchantiophyta) described from the North Pacific based on integrative taxonomy

The molecular and morphological variability of Hygrobiella laxifolia (Hook.) Spruce across its distributional area was investigated to verify its genetic entity. We sequenced nuclear ITS1–5.8S rDNA and three plastid genomic loci (trnL–F, trnG-intron and matK) of 31 specimens referred to H. laxifolia and gathered from remote regions: northwestern European and Far Eastern parts of Russia, as well as western USA. Three robustly supported clades within “H. laxifolia” were obtained by maximum parsimony, maximum-likelihood analyses and Bayesian approach. Haplotype network reconstruction also revealed three haplotype groups separated from each other by a row of missing haplotypes. The majority of Far Eastern accessions were composed of two genetic entities and were contrary to a third one containing all samples from northwestern European Russia, western USA and Bering Island as well. As a result of critical morphological reinvestigation for each of the discovered genetic entities, diagnostic characters were provided and a hypothesis of cryptic speciation in H. laxifolia was not supported. Accessions from removed localities united in a third clade were classified as typical H. laxifolia, whereas Far Eastern specimens from two other clades were applicable to new species—Hygrobiella intermedia Bakalin & Vilnet sp. nova and H. squamosa Bakalin & Vilnet sp. nova, which are described and illustrated here. The re-evaluation of species morphology indicated that the presence of secondary pigmentations, form of perianth and leaves, stem cross section anatomy and length of underleaves appear to be the main differentiation features. Available data suggest sympatric distribution of three Hygrobiella species in the northern Pacific region and the origin of two new species under the strong impact of volcanism.