When studying the phylogenetic relationships of closely related species, it is often difficult to find nuclear DNA regions that are both easy to amplify across taxa and contain informative characters. To address this problem, we have created a database of gene sequences specifically selected to greatly increase both the likelihood of amplification across the species of interest and the likelihood of retrieving nuclear regions that are variable among these species. This result is achieved by designing primers flanking putative intron splicing sites within highly conserved genes. Over 40 species were sampled spanning rosids (14 taxa), asterids (12 taxa), grasses (seven taxa) and other angiosperms, as well as several gymnosperms, a moss, and a green alga.

The application of genetic tools for studying species delimitation and relationships in Sphagnum (peatmosses) has demonstrated that evolutionary patterns are complex and include homoploid hybridization and multiple taxa of allopolyploid origin. We investigated evolutionary relationships in the so-called S. fimbriatum complex and tested hypotheses of species delimitation derived from patterns of morphological variation, and determined the origin of one species with diploid gametophytes. Plastid DNA sequences resolve a single haplotype shared by one described species, S. concinnum, and a morphotype that we had hypothesized to be another species (referred to informally as S. “diskoense”). All samples of the polyploid, S. tescorum, share an identical haplotype with most samples of S. girgensohnii. Sphagnum fimbriatum and S. girgensohnii share several plastid DNA haplotypes, and also share haplotypes with two other morphotypes that we had hypothesized to be distinct species (S. “obscurum” and S. “ubertum”). Fixed or nearly fixed heterozygosity at ten microsatellite loci show that S. tescorum is an allopolyploid. Genetic admixture analyses and computation of hybrid indices from microsatellite data, in combination with sequences from the plastid genome, support the hypothesis that S. fimbriatum and S. girgensohnii are progenitors of S. tescorum, with S. girgensohnii as the maternal parent. Data from 14 microsatellite loci demonstrate that S. concinnum, S. fimbriatum, S. girgensohnii, and S. tescorum are genetically distinct but the same data do not support separation of S. “diskoense,” S. “obscurum,” and S. “ubertum.” Homoploid hybridization between S. fimbriatum and S. girgensohnii is strongly suggested by genetic data and phylogenetic analyses.

The development of a gametophyte within the confines of the spore (i.e. endospory) is one essential innovation toward the evolution of seeds, but this feature also arose in seedless plants. In bryophytes, spores may begin to divide prior to dispersal and germination, but always develop into a free-living gametophyte. In hornworts, multicellular spores occur only in Dendroceros although they have also been observed in cultures of Phaeoceros carolinianus. Here, we describe a new species of Nothoceros, N. renzagliensis, from Pasto, Colombia, that differs from its congeners by its endosporic condition and Dendroceros-like spores. Gametophyte anatomy and sequence data from all cellular compartments place this species within the genus Nothoceros and as the sister taxon to all Neotropical Nothoceros. We re-evaluate the evolution of endospory in hornworts and we show two cases of parallel evolution of this trait across the hornwort phylogeny. Endospory seems to be a highly homoplastic feature across all bryophytes with several independent origins in mosses and liverworts.

Two new species of Blechnum from Para State, northern Brazil, are described along with a diagnostic key and illustrations: Blechnum areolatum and B. longipilosum (Blechnaceae). Blechnum areolatum can be distinguished by: partially anastomosing veins, one or two pairs of pinnae and one- to two-celled hairs present only on the abaxial side of leaf blade. Blechnum longipilosum is characterized by: partially anastomosing veins, one to three pairs of reduced proximal pinnae and long hairs on rachises, costae, veins, laminar tissue, and indusia between sporangia. Both plants belong to the B. occidentale L. complex. Blechnum areolatum is similar to some specimens of B. lanceola Sw. with one pair of pinnae, but the veins in the latter species are completely free. Blechnum longipilosum has no known close relatives. The only Neotropical species so far known with partially anastomosing veins is B. heringeri Brade, which has erect rhizomes (vs. short creeping in B. longipilosum) and short, two- to three-celled hairs on leaf blades, which are deltoid and truncate at base. A key to the Neotropical species of Blechnum with partially anastomosing veins is provided.

Philodendron section Schizophyllum comprises a small group with pinnatifid leaves with eight species: P. quinquelobum, P. squamiferum, P. pinnatilobum, P. bipennifolium, P. pedatum, P. ruthianum. and two new species, P. nadruzianum and P. longilobatum here described from Mata Atlântica forest, southeastern Brazil. The study includes also a key for the Philodendron section Schizophyllum species.

The monotypic genus Lorenzia E. G. Gonç. (Araceae — Spathicarpeae), with the type species Lorenzia umbrosa E. G. Gonç. is described and illustrated. It was collected in 2003 in Amapá state (Northern Brazil). Its novelty was predicted based on molecular phylogeny, but it was not until a cultivated specimen flowered in 2010 that was it possible to confirm its diagnostic morphological features. Evolutionary relationships (based on cpDNA marker matK) are discussed. Lorenzia is known only from a single remote locality in Serra do Navio, a moderately hilly portion of the Amazon, although it is possible that it also occurs in adjacent French Guiana.

A new species of Thismiaceae, Thismia betung-kerihunensis Tsukaya et H. Okada, found during a botanical survey of Betung-Kerihun National Park, West Kalimantan, Borneo, Indonesia, is described and illustrated. This species closely resembles Thismia clavigera (Becc.) F. Muell, which is distributed in Borneo, Sumatra, Langkawi, and Thailand; however, it differs in flower shape, size, and color, having conspicuous hood-like appendages at the tip of the brilliant blue-green colored mitre formed by the three inner tepals. Moreover, it differs in the shape of the anther connectives that lack acutely elongated apices and has rectangular glands. The smaller stature of the species also distinguishes it from T. clavigera.

We present a taxonomic revision of the Cohniella species occurring south of the Amazon River in South America. In this revision, we recognize a naturally occuring hybrid and six species, one of which is herein proposed as new, Cohniella caatingaensis, restricted to the Caatinga of northeastern Brazil. Furthermore, we clarify the specific circumscriptions and distribution range of C. binotii, C. cepula, and C. sprucei. Based on vegetative and floral morphology, we recognize two species groups, the C. jonesiana and the C. cepula complexes. Detailed taxonomic descriptions are given for all species, including short accounts of their distribution and ecology, diagnostic characters, variation range, taxonomic comments, and additional material examined. Relevant iconography is listed for each species. Additionally, a key and a table featuring diagnostic characters to distinguish between species are provided as well as distribution maps for each species-complex.

The systematic position of the little-known Andean species Spiranthes glabrescens, previously known only from Peru but here recorded for the first time from Ecuador, was investigated by means of parsimony and Bayesian analyses of cpDNA and nuclear DNA sequences. Our results indicate that this species is only distantly related to both Spiranthes and Cyclopogon, the genera in which it has been included by previous taxonomists. Instead it is recovered as sister to a clade formed by Eurystyles and Lankesterella, with strong support from the Bayesian analysis. The new, monotypic genus Quechua is proposed to accommodate former S. glabrescens, which differs from both Eurystyles and Lankesterella in habit as well as in vegetative and reproductive characters. The main ecological and structural features of Quechua glabrescens are discussed and compared with those of other genera of Spiranthinae.

Sisyrinchium (Iridaceae) is a New World genus of approximately 140 species. Seventy-five accessions from sixty species representing the geographical and morphological diversity present within the genus were included in this study. Maximum likelihood and Bayesian inference analyses utilized ITS and matK/trnK datasets, analyzed separately and combined. Based on this study the genus Sisyrinchium is monophyletic and is sister to Olsynium. The currently accepted subgenera, Echthronema and Sisyrinchium, are not monophyletic. Instead, all analyses revealed eight major clades, which correspond to named sections or are given informal clade names. Relationships among the eight major clades are resolved except for early diverging clades where topologies for the two DNA-region trees did not agree. Additionally, several widespread species are not monophyletic based on data from these two molecular markers.

Allium subgenus Melanocrommyum is a species-rich group of perennial onions with uniform karyology, ecology, and breeding system. Thus, the cytological, ecological, and physiological factors often correlated with genome size should have negligible effect on genome size variation in Melanocrommyum. We measured DNA content in subgenus Melanocrommyum using flow cytometry based on propidium iodide staining and analyzed the evolution of genome size in a phylogenetic context. The observed 2C genome size variation in 160 accessions of 70 species of the subgenus was high, varying from 26.26–78.73 pg. The significant phylogenetic signal in genome size data suggests that distribution of genome size is in accordance with phylogenetic clades identified by the analysis of nuclear ITS sequences. Estimation of ancestral genome sizes using generalized least squares revealed lineages with increasing as well as decreasing DNA content. We found within-species genome size variation to be mostly below 2.5%. In species where intraspecific genome size differences were in a range of 6–9%, we suggest the existence of cryptic species, as previously inferred by molecular markers. Thus, genome size variation reflects incipient speciation or diversification in Allium subgenus Melanocrommyum. About two-fold differences in DNA content in several Melanocrommyum species indicate the occurrence of diploid and tetraploid cytotypes in these taxa, which for some species has been confirmed by chromosome counts.

The genus Scutachne (Poaceae, Paniceae) is revised. This American genus, which included two species from the Caribbean, was circumscribed on the basis of morphological and molecular characters. To analyze both species of the genus, S. amphistemon and S. dura, a detailed study of the micromorphology of the upper anthecium and leaf anatomy, together with exomorphological characters, was performed. Both species differ in vegetative and reproductive characters, including blade distribution, ligules, presence of axillary inflorescences, consistency of upper glume, lower lemma, and lower palea, presence of a lower flower, upper anthecium ornamentation, and presence of a rachilla extension. Anatomically, S. dura is a C₄ PCK species, while S. amphistemon is a C₃, non-Kranz taxon. The molecular phylogenetic analysis supports these morphological differences. As a result, we concluded that Scutachne, as presently circumscribed, is a polyphyletic genus. Therefore, the genus is here redefined and S. amphistemon is transferred to the new genus Mayariochloa. Affinities of the new genus with other genera of Paniceae are also discussed.

Ichnanthus belongs to the grass subfamily Panicoideae and is characterized by the presence of winged appendages at the base of the upper lemma or by their scars. The genus includes about 30 species that predominate in Neotropical forests, with a great diversity found in Brazil. A new species, Ichnanthus longhi-wagnerii, is herein described, illustrated, and compared with its congeners. We also present geographical and ecological information, as well as SEM micrographs of the upper anthecium. This new species was previously collected in a submontane Atlantic moist forest in Southern Bahia, Brazil, but was not found during recent fieldtrips and is therefore considered endangered.

We investigated the phylogeny of the New World grass Dissanthelium to explore its monophyly, to examine relationships within the genus, and to investigate its relationship with Poa. Molecular phylogenetic analyses including a thorough sampling of Dissanthelium (seventeen of the 20 species) and DNA sequences from the nuclear ribosomal ITS and plastid trnT-trnL-trnF regions suggest that Dissanthelium is not monophyletic and is nested within Poa. However, ten species form a strongly supported clade (the Dissanthelium clade) in the ITS tree. We propose treating Dissanthelium and Tovarochloa as taxonomic synonyms of Poa. We erect two new sections in Poa: sect. Dissanthelium, comprising the Dissanthelium clade and D. peruvianum, and the monotypic sect. Tovarochloa. The necessary new combinations (Poa aequalis, P. amplivaginata, P. calycina var. mathewsii, P. gigantea, P. macusaniensis, P. rahuii, and P. trollii) and new names (Poa sections Dissanthelium and Tovarochloa, P. apiculata, P. arcuata, P. boliviana, P. congesta, P. deminuta, P. linearifolia, P. parvifolia, P. serpaiana, P. swallenii, and P. thomasii) are effected herein.

Piresia is a low growing perennial grass in the tribe Olyreae (Poaceae, Bambusoideae). It differs from other herbaceous bamboos in having dimorphic culms: aerial ones bear broad and flat leaf blades at the top and rarely develop an inflorescence, and decumbent ones usually bear reduced leaves or bladeless leaf sheaths, with inflorescences that are raceme-like, few-flowered, and often hidden under the litter. Four species are accepted in this genus, and a fifth one is described and illustrated herein, Piresia palmula. This new species resembles P. leptophylla in having narrow leaf blades, but differs in the number of aerial culms, texture of leaf blades, and in the number and size of inflorescences on both aerial and decumbent culms. Both species are associated with rainforest remnants, but display distinct patterns of geographic distribution and environmental conditions. Piresia leptophylla occurs in northern South America and northeastern Brazil (Bahia to Paraíba), often in sandy soils, especially in “Restinga” forests, whereas the new species is known only from Michelin's Ecological Reserve, in southern Bahia, growing on rocky substrate in a humid environment. For these reasons it is considered as CR (critically endangered) according to IUCN criteria.

Previous phylogenies based on molecular data indicated that segregate genera from both the Northern and Southern Hemispheres (Hepatica, Pulsatilla, Knowltonia, Oreithales, and Barneoudia) are embedded within Anemone and should be subsumed within the genus. Based on a new phylogeny that substantially increases the sampling of the austral anemones (especially from Africa), we present a formal reclassification of Anemone s. l. We analyzed combined sequence data (chloroplast atpB-rbcL spacer and nuclear ITS regions) for 55 species of Anemone s. l., using Bayesian inference, maximum likelihood, and maximum parsimony. The segregate genera, Oreithales and Barneoudia, nest within Anemone and are included in a well supported clade (subgenus Anemone, section Pulsatilloides) consisting largely of Southern Hemisphere species. The Mexican A. mexicana is sister to all remaining members of section Pulsatilloides, which consists of two clades: a poorly supported South American and Tasmanian clade (A. sellowii, A. helleborifolia, A. rigida, Barneoudia and Oreithales species, and A. crassifolia) and a highly supported southern African clade including nine species of Knowltonia and eight species of Anemone. Anemone antucensis (Chile, Argentina) falls in a separate clade (subgenus and section Anemonidium) that is sister to A. tenuicaulis (New Zealand). Anemone thomsonii (eastern Africa) and A. somaliensis (Somalia) are in a clade (subgenus and section Anemone) composed largely of Northern Hemisphere species. Anemone somaliensis is further associated with other Mediterranean tuberous anemones in subsection and series Anemone (A. coronaria, A. hortensis, and A. pavonina). The topology of both sections Pulsatilloides and Anemonidium suggest that anemones originated in the Northern Hemisphere and subsequently spread to the Southern Hemisphere, a pattern that is shared with other members of Ranunculaceae. We present a formal reclassification of Anemone s. l., including the following new combinations and taxa of Anemone subgenus Anemone: subsections Alchemillifoliae, Anemonanthea, Barneoudia, Crassifoliae, Helleborifoliae, Kilimansharicae, Mexicanae, Oreithales, Rigidae, and Sellowii; series Carolinianae of subsection Anemone; plus the new combination Anemone balliana (= Barneoudia balliana).

The North American creosote bush (Larrea tridentata, Zygophyllaceae) is a widespread and ecologically dominant taxon of North American warm deserts. The species is comprised of diploid, tetraploid, and hexaploid populations, and touted as a classical example of an autopolyploid taxonomic complex. Here we use flow cytometry and DNA sequence data (non-coding cpDNA and nuclear ribosomal DNA) to evaluate spatial and evolutionary relationships among cytotype races, as well as the origins of the species from its South American ancestors. We find the geographic distribution of North American cytotypes to be highly structured, with limited co-occurrence within populations. Diploids reside only in the Chihuahuan Desert, as reported in previous biosystematic surveys, but tetraploid and hexaploid populations interdigitate along the margins of the Sonoran and Mojave Deserts. In phylogenetic analyses, North American plants comprise a monophyletic grouping that is sister to the South American diploid species, L. divaricata. North American populations exhibit genetic signatures of rapid demographic expansion, including a star-shaped genealogy, unimodal distribution of pairwise haplotype differences, and low genetic structure. Nonetheless, polyploid cytotypes are consistently distinguished from diploid cytotypes by a cpDNA indel character, suggesting a single origin of tetraploidy in the species. These findings suggest a recent origin of the North American creosote bush via long distance dispersal, with establishment of polyploid populations accompanying its rapid spread through the Northern Hemisphere.

A taxonomic revision of the Neotropical dioecious genus Lacunaria (Quiinaceae / Ochnaceae s. l.) is presented including keys to the species and subspecies, descriptions, illustrations, nomenclature, typification, and geographical distribution of each species. Seven species are recognized within the genus, one subspecies, L. jenmanii subsp. subsessilis, is described newly, and the status of Lacunaria decastyla has been changed, transferring it to Lacunaria crenata subsp. decastyla. Leaf pubescence, number of secondary veins, and petal, stamen, and carpel number, although all quite variable, are the most important characters to distinguish the species.

Two new species of Tibouchina, tribe Melastomeae (Melastomataceae), are herein described, illustrated and compared with their congeners. Tibouchina bracteolata and T. comosa have dense inflorescences and pentamerous flowers, with two narrow and deciduous bracteoles, and are morphologically similar to T. regnellii Cogn. and T. nodosa Wurdack, respectively. Moreover, they can be distinguished by vegetative and floral characters, as well as by phytogeographic aspects. The two new species were found exclusively in mountainous areas of the Chapada Diamantina, Bahia, Brazil, they are endemic to this region and correlated with distinct vegetation types: ‘campo rupestre’ (T. comosa) or riparian forest (T. bracteolata). On the other hand, T. regnellii is known only to the Atlantic forest of southern Brazil, while T. nodosa occurs in the ‘cerrado’ vegetation from central and southern Brazil.

A taxonomic revision of the genus Hortia (Rutaceae) is presented. Hortia is a Neotropical genus with most of the species occurring in the Amazonian region. The species are woody, nearly all trees, with simple leaves crowded near the apices of the branches, showy broad corymbose terminal inflorescences, reddish to pink flowers, and berries with abundant oil glands. Ten species are recognized here, most of them occurring in Brazil. A key to the species, descriptions, synonyms, illustrations, as well as comments on the geographic distribution, ecology, and economic uses of each species are presented.

A new species, Jarandersonia pentaceoides (Malvaceae-Brownlowioideae), endemic to central Kalimantan, Borneo is described and illustrated. Salient morphological features of the new species that can be used to distinguish it from previously known species of the genus (i.e. J. clemensiae, J. parvifolia, J. purseglovei, J. rinoreoides and J. spinulosa) are tabulated. These include: the densely stellate-lepidote and dentate-lepidote edges of tertiary veins and honeycomb-like quaternary veins on the lower leaf surface, the kneed petiole that is swollen at both ends, and the sparsely stellate-lepidote and tufted-hairy seed coat. A key to the species of Jarandersonia is provided, as is a map of its distribution.

Tripodanthus consists of three species that are endemic to South America. While T. acutifolius and T. flagellaris have east-west distributions in tropical and subtropical South America, T. belmirensis is restricted to its type locality in the region of Belmira, Colombia. The objective of the present study was to reconstruct the phylogeny of the genus using molecular markers (nrDNA ITS and plastid atpB-rbcL and trnL-F regions) and to examine morphological characters in the variable species T. acutifolius. A total of 23 individuals of Tripodanthus, representing all species currently recognized in the genus, were sampled in the molecular phylogeny, while 73 individuals were measured for the morphological component of this study. Phylogenetic analyses of the combined ITS and plastid markers reconstructed two main clades within T. acutifolius that correspond to two geographic areas: the Andes and the eastern region of southern South America. This analysis also yielded a monophyletic T. flagellaris, although no geographic structure was obtained within this clade. Tripodanthus belmirensis and T. acutifolius together formed a clade that was sister to T. flagellaris. A principal component analysis of 70 individuals of T. acutifolius showed great variability in leaf morphological characters, leading to overlapping clusters for Andean and eastern mistletoes. The morphologically variable T. acutifolius was not well supported as monophyletic and possessed overlapping morphological features with T. belmirensis, calling into question whether T. belmirensis should be recognized as a distinct species.

The Californian Silene multinervia (Caryophyllaceae) and Eurasian members of section Conoimorpha in subgenus Behenantha are the only Silene species that have calyces with 15 or more prominent parallel, unbranched veins. We show that S. multinervia, which has been considered a recent introduction of the Asian S. coniflora (section Conoimorpha) to North America, is clearly not synonymous with the latter species based on morphological or molecular data. We present a chromosome count of S. multinervia (2n = 24), which is different from the base number x = 10, a putative synapomorphy for section Conoimorpha. Gene trees based on sequences from three different genomes fail to group S. multinervia with the European section Conoimorpha species. The S. multinervia sequences form a monophyletic group placed in an unresolved position within subgenus Behenantha.

Morphological and molecular evidence has recently revealed the paraphyly of Sebaea (Gentianaceae: Exaceae), and support the establishment of three genera corresponding to highly supported clades. Consequently, the reinstatement of both Exochaenium and Lagenias as genera segregated from Sebaea is proposed here. Exochaenium consists of 22 species distributed in tropical continental Africa that are characterized by papillate stigmas and cubical seeds with star-shaped testa cells. Lagenias is a monotypic genus endemic to the Western Cape Province of South Africa, which differs from Exochaenium and Sebaea by its medifixed anthers, the insertion of the filaments at the base of the corolla tube, and cubical seeds with polygonal testa cells. The synapomorphies of Sebaea s. s. are the presence of secondary stigmas along the style and seeds with rectangular testa cells arranged in parallel rows. Differences with the other genera of tribe Exaceae (Exacum, Gentianothamnus, Klackenbergia, Ornichia, and Tachiadenus) are discussed. In addition, diagnostic characters as well as keys to the genera of the tribe and species of Exochaenium are provided. To account for the new circumscription of Exochaenium, 12 new combinations are also published here (Exochaenium alatum, E. caudatum, E. clavatum, E. dimidiatum, E. fernandesianum, E. hockii, E. lineariforme, E. macropterum, E. oliganthum, E. perparvum, E. rotundifolium, and E. wildemanianum).

A new species Strychnos dantaensis was discovered in lowland forest of Poço das Antas Biological Reserve, and is the unique tree species of the genus Strychnos in Rio de Janeiro State. The new species is related to S. trinervis (Vell.) Mart., but differs by its arborescent growth form, absence of tendrils on branches, ovate calyx lobes, and oblong anthers. Strychnos dantaensis should be treated as endangered under IUCN red list criteria due to its restricted geographical distribution in the Atlantic Rain Forest, an ecosystem in continuous decline.

The present paper provides a large-scale taxonomic revision of Picris hieracioides, a highly polymorphic and taxonomically controversial species in Europe. Altogether, 104 populations were sampled and examined using multivariate morphometrics and genetic amplified fragment length polymorphism (AFLP) data. Two morphotypes are delimited, the ‘higher altitude’ and the ‘lower altitude’ morphotypes, which are congruent with the two main genetic groupings revealed by AFLP markers. It is concluded that two subspecies should be recognized within this species, P. hieracioides subsp. hieracioides, comprising annual to biennial plants occupying dry, sunny, often man-made habitats at low altitudes, and P. hieracioides subsp. umbellata, being mostly a short-lived perennial that grows in mesic, semi-natural or natural habitats at higher altitudes. This infraspecific treatment strongly contrasts with the traditional taxonomic concepts, which recognize up to 10 subspecies of P. hieracioides in Europe. An identification key and a nomenclatural account are presented, including the designation of lectotypes. Picris hieracioides harbors large genetic variation, and two lineages can be recognized within each subspecies, most likely reflecting their glacial survival and postglacial colonization routes. Long-distance dispersals, anthropogenic introductions and recent spread are suggested to have shaped their genetic structure as well. A Balkan endemic P. hispidissima, although morphologically and ecologically well defined, appears to be genetically close to P. hieracioides.

The Pacific species of the polyphyletic genus Schefflera belong to three main clades, of which the Melanesian Schefflera clade is best represented in the archipelagos of New Caledonia, Fiji, Vanuatu, and the Solomon Islands. Previous studies have helped to establish the monophyly of Melanesian Schefflera, but an informal, morphology-based classification system that recognizes five subgeneric groupings within this clade remains largely untested. To examine relationships among Melanesian Scheffleras, DNA sequence data from two spacer regions (ITS and ETS) of the nuclear rRNA genes were gathered from a nearly comprehensive sample of species and analyzed phylogenetically. Results confirm the monophyly of four of the five informal groupings, including ‘Plerandra’ (from Fiji, Vanuatu, Solomon Islands, and New Guinea), ‘Gabriellae’ (from New Caledonia, Fiji, and Vanuatu), ‘Canacoschefflera’ (New Caledonia), and ‘Dictyophlebes’ (Fiji and Solomon Islands). However, rDNA data do not agree with morphology in regard to the fifth group, ‘Dizygotheca,’ which appears polyphyletic in the cladograms based on ITS and ETS sequences.