The moss genus Taxithelium is reclassified into two subgenera: Taxithelium and Vernieri. The subgenus Vernieri can be distinguished from subgenus Taxithelium by the lanceolate leaves and filamentous pseudoparaphyllia in the former and ovate leaves plus foliose pseudoparaphyllia in the latter. The subgenus Vernieri is revised here and comprises eleven species; one from Africa, two from the Americas, and the remaining from Southeast Asia and Oceania. Keys, illustrations, and descriptions are provided.

The distribution of Sphagnum cuspidatum has been subject to controversy. Although historically reported from all continents except Antarctica recent authors consider S. cuspidatum to be endemic to Europe and eastern North America. Microsatellites from Australian plants morphologically identified as S. cuspidatum were compared to microsatellites of plants morphologically identified as S. cuspidatum collected from other regions. The species was found to occur in Australia as well as on every continent except Antarctica. The sample most closely related to the Australian plants was collected in the Philippines, and samples from Australia, the Philippines, Colombia, and Equatorial Guinea formed a subclade within S. cuspidatum. Microsatellites further show that S. cuspidatum is one of the parental species of the double allopolyploid S. falcatulum, a Holantarctic species which is reported from Tasmania, New Zealand, and Chile.

The genus Hexalobus consists of five species characterized by six basally fused petal lobes that are transversally folded in bud, which is unique within Annonaceae. The genus is widespread across tropical Africa occurring in rain forest, savanna, and woodland. The species H. callicarpus, occurring in Madagascar, is excluded from Hexalobus, so the genus is now restricted to continental Africa. The present revision provides a synthesis of previously published information and discussions on morphology, taxonomy, phylogeny, and palynology. Conservation status assessments are provided for each species, as well as a diagnostic key and detailed species descriptions. Furthermore, four species are illustrated and all species are mapped.

A new genus and species of mycotrophic orchid (Orchidaceae), Kalimantanorchis nagamasui Tsukaya, M. Nakajima et H. Okada, from Betung Kerihun National Park, West Kalimantan, Borneo, Indonesia, is described and illustrated. Kalimantanorchis resembles the genus Tropidia Lindl. in flower and stem morphology, namely, mycotrophic habit, branching stem, nonresupinate flowers with a saccate cymbiform lip bearing two longitudinal ridges along the margins, broadly triangular rostellum, acute, triangular anther cap, and winged or three-lobed column. It differs, however, in having a tuberous root system, pure ivory-white flower coloration and four pollinia. BLAST analyses based on DNA sequences of the chloroplast matK pseudogene and ITS of the nuclear ribosomal DNA also suggest that the closest genus is Tropidia Lindl., but the similarity is low and a molecular phylogenetic analysis did not support it to be a member of Tropidia, confirming the idea that this is an undescribed genus.

Two new species of Paniceae are here described, one belonging to Dichanthelium (Dichanthelium barbadense) and the other to Panicum sect. Laxa (Panicum harleyi). Both taxa grow in open areas of Central Brazil are described, illustrated, and compared with putative related species.

The Peruvian Poissonia eriantha is segregated from peripatric Poissonia orbicularis and reinstated as the third unifoliolate species of Poissonia and the second from the Apurimac River basin in Peru. Poissonia eriantha is distinguished phenotypically and by DNA sequences from the ITS and cpDNA trnD-T region and morphology. This overlooked species is known from the type specimen and a recent collection from north of the Apurimac River in westcentral Cuzco where seasonally dry tropical forest vegetation predominates that is rich in succulent taxa (e.g. Cactaceae). Poissonia orbicularis is known from downstream along the Apurimac River and is disjunct further north along the Mantaro River, all within the same kind of seasonally dry vegetation. This seemingly small geographic distinction belies large genetic and phenotypic differences, a finding that may be most common to species groups confined to seasonally dry Neotropical forest vegetation. The case of Poissonia eriantha exemplifies the potentially high degree of niche conservatism and dispersal limitation that seasonally dry succulent-rich woodlands can impose on its constituent lineages.

Three woody species of Coursetia from eastern Brazil are here classified into the Rostrata clade, Coursetia caatingicola, C. rostrata, and C. vicioides. All come from the Southern Sertaneja Depression of the caatinga, and the first of these is herein described. The antiquity of this geographically confined clade is suggested by its phylogenetic isolation within Coursetia and minimum age estimates of about 9 Ma for each of the species stem clades and about 17 Ma for the Rostrata stem. These age estimates were biased young and are associated with ITS rates of substitution of about 2–3 × 10^-9 substitutions per site per year, an expected rate for woody plant lineages. Multiple DNA sequence accessions coalesce with respect to nuclear ribosomal 5.8S and internal transcribed spacer (ITS) sequences for Coursetia caatingicola and C. rostrata, and with respect to chloroplast trnD-T sequences for Coursetia caatingicola. Coalescence of conspecific nuclear DNA sequence samples combined with relatively old minimum age estimates are suggestive of the evolutionary stability of local patches of seasonally dry tropical vegetation that are rich in succulent taxa. This phylogenetic signature is more likely to be found in lineages harbored by this than other types of Neotropical vegetation.

The Ficus petiolaris complex, comprised of F. brandegei, F. jaliscana F. petiolaris and F. palmeri, is a group of Mexican endemic fig species where disagreement on their recognition still exists. Sixteen populations belonging to these taxa were analyzed to resolve their taxonomic status. Data on morphological and micromorphological characters were gathered. Multivariate and univariate statistical analyses as well as diagnostic character analyses were carried out with populations as units of analysis. In addition, correlation tests and regression analyses were performed with continuous morphological characters, geographic location, and the amount of precipitation to detect any clinal variation. Results indicate that continuous quantitative characters traditionally utilized to differentiate taxa in the Ficus petiolaris complex exhibit clinal variation. Petiole length, leaf width, and fig area decrease with latitude and longitude. There is a positive relationship between petiole length and leaf width with latitude and precipitation. Statistical analyses did not identify diagnostic characters for the previously recognized species. Characters such as branch pubescence, color of leaf veins, and pubescence and spots over figs utilized for differentiating taxa were found to vary within and among populations. Therefore, Ficus petiolaris, the first name described in this complex, is recognized as the only species that should be recognized, with a wide distribution from Sonora to Oaxaca and in Baja California.

Croton section Pedicellati is described, with a disjunct distribution in Mexico and South America. It is recovered sister to Croton section Lamprocroton in Bayesian, Maximum Likelihood, and Maximum Parsimony analyses of nuclear ITS and chloroplast trnL-F DNA sequence data. Two new subsections, Croton subsection Lamprocroton and Croton subsection Argentini, are recognized within Croton section Lamprocroton. These well-supported sister clades include species with bifid and multifid styles, respectively. Croton breedlovei, a new lepidote species of section Pedicellati, endemic to Chiapas, Mexico, is described. Croton breedlovei is morphologically and phylogenetically closer to other lepidote species from Brazil than it is to the stellate C. tenuilobus, also from Mexico. This suggests two separate dispersal events from South America for the two Mexican species in the section. The replacement names C. longicolumellus and C. tenuicaulis are made for the later homonyms C. microcarpus and C. microstachys. Lectotypes are designated for C. andinus, C. angustifrons, C. burchellii, C. catinganus, C. cerino-dentatus, C. cerino-dentatus var. martii, C. cerino-dentatus var. warmingii, C. cuyabensis, C. eriocladoides, C. linearifolius, C. microcarpus, C. microstachys, and C. saxosus.

Phyllanthus comprises approximately 1,270 species, making it one of the world's largest plant genera. Molecular data so far are of limited value for understanding Phyllanthus because of the sheer size of the genus. They can, however, help sort-out cryptic species and provide information on the origin of suspected introduced species. One of the seemingly most widespread species is P. reticulatus, which has been recorded from Asia, Australia, Africa, and Jamaica. The name is based on a mixed collection from tropical Asia now in the Lamarck herbarium, and we lectotypify it here. We use nuclear ITS sequences to test the broad treatment of P. reticulatus in recent floras, identify records of “P. reticulatus” from Africa, and investigate the origin of P. reticulatus on Jamaica. A maximum likelihood tree for accessions of P. reticulatus from throughout its supposed range (plus relevant outgroups) shows that the Jamaican plants represent the Asian species, that the African plants called P. reticulatus belong to a separate clade for which P. polyspermus is the oldest available name, and that the sensu lato treatment of P. reticulatus in recent floras is unjustified. Treating the Asian entities P. reticulatus and P. microcarpus as separate species appears justified, and identical ITS sequences in Asian and Jamaican P. reticulatus indicate a recent introduction. The first “island botanists,” J. Macfadyen and N. Wilson, introduced many plants from India in the 1800s, and theirs are the oldest Jamaican collections of P. reticulatus. Since the species was introduced to Jamaica without its obligate Epicephala moth pollinators, it does not set fruit, persisting instead by vegetative growth.

New World Podostemaceae (riverweeds) comprise approximately 135 species in 21 genera, most of which are of tropical distribution, shed pollen in monads, and belong to subfamily Podostemoideae. We undertook a phylogenetic study of Neotropical Podostemoideae using molecular (ITS, rbcL, trnL) and morphological data, to assess the monophyly of genera and their interrelationships. Extensive taxon sampling (38 taxa in 15 genera) revealed that the large genera Apinagia and Marathrum are not monophyletic as currently circumscribed, although several species of the former comprised a clade that could be delimited morphologically by the shared character of upright stems (i.e. anchored to the substrate only basally). Marathrum species were split geographically, with Central and South American taxa resolving in different clades. Oserya also comprised two geographically disparate clades, with the type species belonging to the South American clade. To establish the monophyly of Oserya, we erected a new genus Noveloa to accommodate the Central American species N. coulteriana and N. longifolia. The Central American Marathrum clade included the monotypic Vanroyenella, which we transferred to that genus as Marathrum plumosum. The genera Castelnavia and Rhyncholacis were monophyletic in our analyses; C. multipartita f. pendulosa was elevated to species rank as Castelnavia pendulosa. The monotypic Lonchostephus resolved within Mourera, with which it shares a number of morphological features that are found also in Tulasneantha (also monotypic), but which otherwise are unique in Podostemaceae. We recommend that Lonchostephus and Tulasneantha be merged with Mourera and provide the new combination Mourera monadelpha for the latter. Finally, an unexpected clade of morphologically diverse genera, including members of Apinagia, Jenmaniella, Lophogyne, Marathrum, and Monostylis, resolved with strong support but uncertain morphological integrity, as sister to all ingroup taxa except Mourera. However, nomenclatural changes in this group have not been made, pending additional taxon sampling and procurement of further molecular and morphological evidence.

Graffenrieda glandulosa can be distinguished from other species in the genus by the 3-nerved leaves with barbate nerve bases on the abaxial surface, the calyptrate calyx, and the short connective appendages covered with glandular trichomes. This new species has been collected only in the western tip of the state of Acre, Brazil, near the border with Peru.

A taxonomic revision of Carapa (Meliaceae) in Ecuador is provided with the recognition of four species, C. megistocarpa which has cauliflorous inflorescences, C. nicaraguensis previously described and currently placed as synonym of C. guianensis and two new species (C. alticola and C. longipetala). The new species are close to C. guianensis based on their 4-merous flowers borne at the end of the branches. However, C. alticola differs from C. guianensis in having larger leaflets with prominent secondary veins, seeds with rounded edges and short poorly ramified inflorescences, while C. longipetala can be distinguised from C. guianensis in having distinctly pedicellate flowers and 6-ovulate ovary loculi. The new species are described, illustrated, and a key to the four species recognized in Ecuador is provided.

Tropical plants show a diversity of growth forms, yet few phylogenies are available to examine the transitions between trees, shrubs, and lianas. Here, we reconstruct relationships among 37 species of Ayenia, Byttneria, and Rayleya with cpDNA sequences, and use the resulting phylogeny to test hypotheses on the evolution of climbing plants and to examine biogeography of these plants. Results show that Rayleya is sister to a combined clade of Ayenia and Byttneria; Byttneria is paraphyletic with Ayenia nested within it. The common ancestor of the combined Ayenia/Byttneria/Rayleya clade is reconstructed as a neotropical tree or shrub. Within the Ayenia/Byttneria clade, there is a single transition to unarmed lianas, with subsequent radiations into the Asian and African tropics. A second independent transition from trees or shrubs to spiny, semi-scandent shrubs occurred in the neotropics. We found no evidence of transitions from lianas to any other growth form; however, we recovered a reversal from semi-scandent shrubs to fully upright plants. Within the neotropics, there are two independent radiations into seasonal, open habitats. Additional sampling of African species of Byttneria may yield more complicated scenarios in both biogeography and the evolution of growth forms.

Macroditassa mantiqueirae , a new species of Apocynaceae-Asclepiadoideae from Minas Gerais, Brazil, is presented. It is morphologically related to M. lagoensis and M. marianae because of the presence of cucullate corona lobes. Macroditassa mantiqueirae can be distinguished from M. lagoensis and M. marianae by the presence of papillose corolla lobes, inner corona lobes cucullate, and by the inflexed apex of the outer lobes.

Alectra sessiliflora (Orobanchaceae) is the most widespread species within the genus, occurring throughout sub-Saharan Africa, and into India, China and the Philippines. Three varieties are currently recognized (A. sessiliflora var. monticola, A. sessiliflora var. senegalensis, and A. sessiliflora var. sessiliflora) and are distinguished by geographic range, calyx pubescence and stamen filament pubescence. Due to the overlapping nature of the characters used to distinguish among these varieties, accurate assignment of a specimen to a single variety is nearly impossible. We undertook a phenetic study of morphological characters to assess the validity of these varieties. Principal coordinate analysis and the unweighted pair-group method using arithmetic averages were used to explore whether specimens would cluster into the currently recognized varieties. Our analyses revealed no clustering based exclusively on geographic distribution. A small cluster of seven specimens was seen in the principal coordinate analysis using Gower's coefficient of similarity as input values, but this cluster was not diagnosable by unique characters. Based on these results we recommend that Alectra sessiliflora be recognized without infraspecific taxa. Finally, additional names are included as synonyms under Alectra sessiliflora based on extensive study of field-collected and herbarium specimens.

DNA sequences from the nuclear gene waxy were used to assess phylogenetic relationships within Jaltomata, a group of approximately 60 species from Central and South America. Phylogenetic analyses identify two primary groups: a morphologically diverse group from western South America, characterized by orange fruits, and a primarily Mesoamerican clade with black/purple fruit and little morphological diversity. We also identify an early-diverging lineage of Jaltomata species with red fruits, which is sister to the rest of the genus. Ancestral character state reconstruction supports a view of the common ancestor of the genus originating in South America and having rotate corollas similar to many species of Solanum. In addition, we infer independent colonizations of lomas habitats by Jaltomata species and show a correlation between red nectar production and campanulate floral form in multiple lineages, suggesting a common evolutionary syndrome related to pollination.

Solanum series Conicibaccata is the second largest series in section Petota, containing 40 species widely distributed from southern Mexico to central Bolivia. It contains diploids (2n = 2x = 24), tetraploids (2 = 4x = 48) and hexaploids (2n = 6x = 72), and the limited number of species examined have been shown to be allopolyploids. Previous morphological and molecular studies using plastid DNA failed to discriminate clear species boundaries. Conserved orthologous nuclear DNA sequences (COSII) were used to compare the relationships among 72 accessions from 22 species from series Conicibaccata and 42 additional accessions from related series. The results supported previous studies showing the diploid members of series Conicibaccata to be related to other South American “clade 4” species, and showed all of the polyploids to be allopolyploids among members of clade 4 and other South American species of “clade 3” (series Piurana and related species). Low bootstrap support values and morphological similarity suggest recent origins and the need for a reduction in number of recognized species in series Conicibaccata.

Morphological variation within and between taxa of the Santolina rosmarinifolia L. aggregate were studied. This work demonstrates that polyploidy and hybridization may be effective evolutionary mechanisms of speciation, promoting the persistence and survival of new species, and ultimately increasing the diversity of plant species. The patterns of morphological variation of the S. rosmarinifolia aggregate indicate a recent diversification process for these taxa; as a consequence they are poorly differentiated. The intriguing taxonomic complexity of the taxa of the S. rosmarinifolia aggregate can probably be explained to a large degree by recurrent hybridization and subsequent interbreeding of the resulting genotypes, and by the absence of karyotypic divergence and of spatial isolation (except for S. impressa) between diploid taxa. Quantitative and qualitative data support two evolutionary lines that are not yet strongly differentiated in this aggregate. On one hand are the diploid and tetraploid cytotypes of S. pectinata and S. ageratifolia, and on the other the remaining taxa. Two new subspecies, S. rosmarinifolia subsp. castellana and S. pectinata subsp. montiberica, are described from the Iberian Peninsula.

The tribe Platycarpheae has three species; they are found from South Africa, to Namibia and Botswana. The three species have traditionally been placed in a single genus but were recently divided into two (Platycarpha and Platycarphella). All have ‘secondary heads’ formed by tightly clustered heads on the crown of the rhizome. The three species are easily separated from one another based on characters such as leaf type, head size, style and corolla length, and pollen type. Morphological and molecular data support Platycarpheae as a monophyletic group within the subfamily Cichorioideae but no firm sister-group relationship has been determined. The three species form a monophyletic group on a long branch: Platycarphella carlinoides and Platycarphella parvifolia share more characters and are sister-taxa; Platycarpha glomerata has the largest number of unique features and is the sister taxon to the other two species. The distributions and flowering times of the three species are different. Platycarphella carlinoides is the most widespread of the species and grows in northwestern South Africa, the central highlands of Namibia, and southwestern Botswana; its peak flowering time is March–July. Platycarphella parvifolia is found in north central to northeast South Africa and flowers mostly in August to October, and Platycarpha glomerata is from inland eastern South Africa and usually flowers from November to early February. The biogeographic pattern is consistent with one of a widespread ancestral species that became fragmented by the rise of the Great Escarpment and climate change.

Solidago houghtonii Torrey & A. Gray ex Gray is a federally threatened polyploid plant species likely of hybrid origin. Several hypothesized combinations of parental species have been suggested but none have been phylogenetically tested. Additionally, it is unclear whether the species is of single or polytopic origin. To study the evolutionary history of S. houghtonii we sequenced four noncoding cpDNA loci (accD-psaI, psbA-trnH, trnL-trnF, rps16-trnQ), and the ITS and 3′ETS regions for four accessions of S. houghtonii, which span its geographic range, and 25 other species of Solidago including all sympatric species. Polymorphisms within the direct nrDNA sequences of all S. houghtonii accessions indicated the presence of multiple homoeologue types. These were separated by molecular cloning of the 3055 bp 3′ETS — ITS region, allowing us to positively link the ETS and ITS homoeologue types. Phylogenetic analyses of the nuclear and chloroplast datasets revealed incongruent topologies. Analysis of cloned nrDNA sequence data indicated that S. riddellii, S. ptarmicoides, and S. ohioensis have contributed to the nuclear genome of S. houghtonii. Analysis of cpDNA sequence data revealed the presence of multiple insertions/deletions that are shared by all accessions. The unique pattern of cpDNA indels was also recovered in S. gigantea. Phylogenetic analysis of the cpDNA sequence data and coded indels indicate S. gigantea is the maternal genome donor. However, we did not recover a S. gigantea nrDNA sequence type. Taken together, these data reveal both a single origin and a complex pattern of reticulation that is consistent not only with the hypothesized allohexaploid nature of this species, but also with chloroplast capture of cpDNA from an unexpected source through introgression.

A new species of the Brazilian endemic genus Acritopappus from the Serra do Cabrai, in Minas Gerais state, is described. The new species, Acritopappus pereirae, is similar to A. confertus, the most widely distributed species in the genus, but differs in that the latter has conduplicate, chartaceous, glabrous to glabrescent, viscid leaves with entire margins, and an aristate pappus. The new species is illustrated, the affinities between the morphologically related species and A. pereirae are discussed and a key to the species from Minas Gerais is provided.

Recent molecular investigations place Heptacodium as sister to the Lonicera clade, whereas morphology suggests a close relationship with the Linnaea clade s. 1. (former tribe Linnaeeae). Zabelia has always been assumed to be closely related or even congeneric with Abelia. This study presents molecular and morphological data in an attempt to further clarify the systematic positions of Heptacodium and Zabelia as they are key genera to help us understand evolution in Dipsacales. Our molecular analyses strongly support a sister relationship between Heptacodium and the Lonicera clade. Zabelia, however, seems to be closer related to the Morina clade than to any other member of the Linnaea clade s. 1. None of our phylogenetic analyses suggest a close relationship between Abelia and Zabelia. Morphologically, Zabelia's relationship with the Morina clade is only supported by the shared presence of psilate pollen grains with an endocingulum. Fruit and seed morphology strongly indicate a close relationship between Abelia, Heptacodium, and Zabelia. Even though wood anatomy of Zabelia is unique in several aspects, it does not aid in unraveling the systematic position of the genus. In the case of Heptacodium, hybridization is a plausible scenario that could explain the uncertain systematic position of the genus. A better understanding of the intergeneric relationships of the Lonicera and Linnaea s. 1. clades is essential to solve this matter.