Showing papers in "Systematic Botany in 2017"
TL;DR: It is concluded that the cottons of Wake Atoll do in fact represent a new species of Gossypium, here named Gossypeium stephensii, chosen to commemorate the eminent natural historian, evolutionary geneticist, and cotton biologist, S. G. Stephens.
Abstract: Wake Atoll is an isolated chain of three islets located in the Western Pacific. Included in its endemic flora is a representative of the genus Gossypium colloquially referred to as Wake Island cotton. Stanley G. Stephens pointed out that “Wake Island cotton does not resemble closely either the Caribbean or other Pacific forms.” Taking into consideration morphological distinctions, the geographic isolation of Wake Atoll, and newly generated molecular data presented here, we conclude that the cottons of Wake Atoll do in fact represent a new species of Gossypium, here named Gossypium stephensii. This name is chosen to commemorate the eminent natural historian, evolutionary geneticist, and cotton biologist, S. G. Stephens.
70 citations
TL;DR: Sapindaceae tribe Paullinieae is newly recognized and morphologically characterized by zygomorphic flowers, thyrses with lateral cincinni, corollas of 4 petals, and alternate leaves with a well-developed distal leaflet.
Abstract: The current study examines all genera of Sapindaceae tribe Paullinieae sensu Acevedo-Rodriguez et al. (2011). Based on molecular phylogenetic analyses of trnL intron and ITS sequence data along with critical evaluation of morphology, supertribe Paulliniodae is newly recognized and morphologically characterized by zygomorphic flowers, thyrses with lateral cincinni, corollas of 4 petals, and alternate leaves with a well-developed distal leaflet. Paulliniodae contains four successively nested subclades designated as tribes Athyaneae, Bridgesieae, Thouinieae, and Paullinieae. Athyaneae contains Athyana and Diatenopteryx, and is composed of trees with exstipulate pinnately compound leaves, and isopolar, spherical, colporate pollen grains. Bridgesieae contains the monospecific shrub genus Bridgesia with exstipulate, simple leaves, and isopolar, spherical, tricolporate pollen grains. Thouinieae is resurrected and amended to include three genera of trees or shrubs with exstipulate trifoliolate or unifoli...
46 citations
TL;DR: A previously-unidentified clade of Southeast Asian endemic taxa is found, including one species formerly classified in Andropogon, and addition of species from mainland Southeast Asian finds unexpected phylogenetic diversity.
Abstract: The grass tribe Andropogoneae is distributed in warm regions around the globe but has been poorly studied in mainland Southeast Asia. This is particularly true for the cosmopolitan genera Andropogon and Schizachyrium, with several species that appear to be narrowly distributed in this region. Additionally, lesser-known species in the genera Hemisorghum, Kerriochloa, and Pseudosorghum also occur inmainland Southeast Asia. A phylogeny is needed to address questions of taxonomy and trait evolution. Whole chloroplast genomes of Andropogoneae species and two outgroup species of Garnotia (tribe Arundinelleae) were analyzed using maximum likelihood (ML) and Bayesian inference (BI). Ancestral character states were reconstructed usingML for four morphological characters key to Andropogon and Schizachyrium identification.Apreviously-unidentified clade of Southeast Asian endemic taxa is found, including one species formerly classified in Andropogon. Other Southeast Asian taxa fall in an unresolved grade outside the major radiation of the tribe. Andropogon and Schizachyrium are both polyphyletic. Convergent evolution and reversal of characters are common throughout Andropogoneae. Addition of species from mainland Southeast Asian finds unexpected phylogenetic diversity. Southeast Asian Schizachyrium sanguineum forms two separate clades, which could reflect cryptic species differentiation, hybridization, introgression, or some combination.
31 citations
TL;DR: Maytenus is segregated into two genera, re-established Tricerma, and maintain Fraunhofera and Plenckia as distinct genera that are morphologically distinct from each other, primarily based on fruit characters.
Abstract: Maytenus species are distributed in the New World from Argentina to the U. S. A. The genus delimitation has been controversial, especially in relation to the inclusion of Gymnosporia. Maytenus has been treated in a broad sense such that it was considered widely distributed in tropics and subtropics worldwide. Even in its current restricted circumscription, the genus remains paraphyletic with Fraunhofera and Plenckia nested within it. We increased taxon sampling relative to previous studies and sampled species representing the greatest morphological diversity from throughout the geographic distribution in order to confidently delimit monophyletic genera. The phylogenywas inferred using nuclear (ITS and 26S rDNA) and plastid (matK and trnL-F) gene regions together with morphological characters. The species currently recognized as Maytenus were resolved in three distinct clades. Delimitation of a single large genus, by including Fraunhofera and Plenckia within Maytenus, would result in a morphologically heterogeneous group. Instead we segregated Maytenus into two genera, re-established Tricerma, and maintain Fraunhofera and Plenckia as distinct genera. All of these genera are morphologically distinct from each other, primarily based on fruit characters. A total of 123 new combinations under the generic name Monteverdia are provided for species in the clade that does not contain the type of Maytenus.
23 citations
TL;DR: A phylogenetic analysis of maternal lineages based on 2,385 aligned nucleotides using maximum likelihood and Bayesian inference to explore genetic diversity and phylogenetic relationships among taxa and suggests multiple origins for at least four polyploid taxa.
Abstract: The moonwort genus, Botrychium s. s., includes diploid and polyploid taxa that occur primarily in the northern hemisphere. Their evolutionary history, morphologically cryptic taxa and deep divergence of the family in the phylogeny of ferns has long fascinated pteridologists. Previous molecular studies did not include a complete taxonomic sampling of the taxa in the genus, nor multiple specimens from throughout the known geographical range of each taxon. Therefore, to investigate evolutionary relationships of the major clades of Botrychium s. s., we increased both taxonomic representativeness (multiple accessions per taxa), as well as phylogenetic resolution by including additional new chloroplast markers. To confirm identification and provide evidence from both maternal and paternal parentage of allopolyploids, we also included specimens that have been characterized by allozyme profiles determined by electrophoretic analysis of 20 nuclear enzyme loci for each taxon. We analyzed four chloroplast regions (matK intron, trnHGUG
—psbA, andtrnLUAA
—trnFGAA
intergenic spacers, and rpL16 intron region) of 365 specimens fromAsia, Europe, North America, Oceania, and South America, sampling the geographical range of 34 of 35 accepted Botrychium s. s. taxa and thirteen putatively new taxa. We conducted a phylogenetic analysis of maternal lineages based on 2,385 aligned nucleotides using maximum likelihood and Bayesian inference to explore genetic diversity and phylogenetic relationships among taxa. We found strong support for themonophyly of three major clades: Lanceolatum, Lunaria, and Simplex-Campestre, and resolved 15 subclades. Our results suggest multiple origins for at least four polyploid taxa (B. boreale, B. michiganense, B. yaaxudakeit, and B. watertonense). The Simplex-Campestre clade had the largest number of species, despite having a similar total number of haplotypes as the Lunaria clade (62 and 59, respectively), which has the broadest worldwide distribution. In total, our new molecular phylogeny comprises 47 taxa, of which thirteen are discussed for possible taxonomic recognition.
20 citations
TL;DR: Patterns of genetic diversity of staminate and pistillate Rafflesia flowers growing on the same Tetrastigma host plants indicate that the R. lagascae complex is monoecious and that host plants are regularly infected by multiple Raffleia plants.
Abstract: Rafflesia lagascae is a rare endo-holoparasitic species with a disjunct distribution on Luzon Island. It is morphologically very similar to R. manillana from nearby Samar. This study aims to contribute to the taxonomy and conservation of R. lagascae and R. manillana (i.e. the R. lagascae complex) by resolving their patterns of genetic diversity and structure. The results of analyses of a microsatellite data set indicate that despite their frequently extremely small sizes and geographic isolation, Rafflesia populations display moderate genetic diversity and do not show evidence of pronounced inbreeding. Most populations appear to have limited gene flow among them. Patterns of genetic diversity of staminate and pistillate Rafflesia flowers growing on the same Tetrastigma host plants indicate that the R. lagascae complex is monoecious and that host plants are regularly infected by multiple Rafflesia plants. PCoA and Bayesian cluster analyses show that the complex is composed of three genetically isolated taxa. One of these constitutes R. manillana, supporting the morphology-based hypothesis that it is taxonomically distinct from R. lagascae. The second taxon in this complex is composed of a morphologically cryptic R. lagascae population from Mt. Labo, which is genetically distinct from all remaining R. lagascae populations that were studied and that form the third taxon. We recommend that these three taxa are managed as different conservation entities.
20 citations
TL;DR: It is argued that P. braunii has expanded to its circumboreal range in the recent past, though it has a relatively ancient origin, and the two origins were in Beringia.
Abstract: Although some polyploids in the genus Polystichum are well studied and have well-resolved evolutionary histories, the origin of the circumboreally distributed allotetraploid Polystichum braunii remains obscure. We use the chloroplast markers rbcL, rps4-trnS, and trnL-F as well as the nuclear markers pgiC and gapCp to demonstrate that P. braunii is a single allotetraploid with a minimum of two origins. The two variants isolated from the nucleus resolve with divergent clades, one eastern Asian and one North American. However, they do not have near allies among morphologically appropriate taxa in our sample; the North American progenitor appears to be extinct. A divergence-time analysis based on the cpDNA markers yielded evidence of an older time of origin for P. braunii than for an array of well-known allotetraploids in the eupolypod ferns. Niche modeling in the light of geological and paleontological evidence leads to the conclusion that the two origins were in Beringia. Since P. braunii is genetically undifferentiated but widely distributed, we argue that it has expanded to its circumboreal range in the recent past, though it has a relatively ancient origin.
19 citations
TL;DR: The phylogenetic results suggest an African origin for the genus Xylopia and reveal complex biogeographic patterns, likely facilitated by long-distance dispersal.
Abstract: The floristic treatment of Engler and Diels, published in 1901, provides the only infrageneric classification of the pantropical genus Xylopia (Annonaceae) Here we test and extend that classification using molecular and seed morphology characters Phylogenetic relationships were reconstructed using data from four plastid regions obtained from 44 of the approximately 165 species in the genus, recovering four well-supported major clades Seed characters were examined for these taxa, and six aril morphologies, three previously undocumented, were distinguished; we also document the presence of a sarcotesta on the seeds of many species Molecular and seed data support recognition of five sections within the genus; one, Xylopia sect Rugosperma, is proposed here as new Our phylogenetic results suggest an African origin for the genus and reveal complex biogeographic patterns, likely facilitated by long-distance dispersal
18 citations
TL;DR: The results imply that the ecology of the earliest angiosperms is critical to understand the pre-Cretaceous evolution of flowering plants, and that the true ages are likely between the authors' extremes.
Abstract: Gaps between molecular ages and fossils undermine the validity of time-calibrated molecular phylogenies. An example of the time gap surrounds the age of angiosperms' origin. We calculate molecular ages of the earliest flowering plant lineages using 22 fossil calibrations (101 genera, 40 families). Our results reveal the origin of angiosperms at the late Permian, ∼275 million years ago. Different prior probability curves of molecular age calculations on dense calibration point distributions had little effect on overall age estimates compared to the effects of altered calibration points. The same is true for reasonable root age constraints. We conclude that our age estimates based on multiple datasets, priors, and calibration points are robust and the true ages are likely between our extremes. Our results, when integrated with the ecophysiological evolution of early angiosperms, imply that the ecology of the earliest angiosperms is critical to understand the pre-Cretaceous evolution of flowering plants.
18 citations
TL;DR: This work reconstructs the phylogeny of the Cephalocereus group using molecular data from seven chloroplast regions, and proposes the transfer of all species of Neobuxbaumia, Cephalecreus, and PseudomitrocereUS to a single genus, in which Cephalancereuses takes priority over the other names.
Abstract: Cephalocereus, Neobuxbaumia, and Pseudomitrocereus (Cactaceae, Cactoideae, Echinocereeae) are related genera of columnar cacti native to Mexico with current ambiguous circumscription. We applied maximum parsimony and Bayesian inference methods to reconstruct the phylogeny of the Cephalocereus group using molecular data from seven chloroplast regions (petL-psbE, psbA-trnH, rpl16, rpl32-trnLUAG, trnL-F, trnQrps16, andycf1), simple coded indels, and 46 structural characters. The Cephalocereus group was recovered as monophyletic with high support values, whereas Neobuxbaumia appeared as paraphyletic, due to the polyphyly of Cephalocereus and the derived position of Pseudomitrocereus within this group. Topology was mostly congruent among the different phylogenetic methods explored, and three pervasive clades were observed. Two structural characters were confirmed as synapomorphies for the Cephalocereus group: prismatic crystals in the dermal system and a perianth woody cap persistent in the fruit. The derived position of Pseudomitrocereus suggests that new hypotheses must be explored regarding the possible hybrid origin of this taxon. We propose the transfer of all species of Neobuxbaumia, Cephalocereus, and Pseudomitrocereus to a single genus, in which Cephalocereus takes priority over the other names. Based on our results, a new circumscription for Cephalocereus is proposed, including a taxonomic synthesis, two new combinations (Cephalocereus multiareolatus and Cephalocereus sanchezmejoradae), and a key for species.
18 citations
TL;DR: Fruit anatomical and micromorphological structures from 28 species of Heracleum and three species of Angelica as outgroups were examined under light microscopy to identify characters useful in delimiting clades circumscribed in a previous molecular phylogenetic study.
Abstract: Fruit anatomical and micromorphological structures from 28 species of Heracleum and three species of Angelica as outgroups were examined under light microscopy to identify characters useful in delimiting clades circumscribed in a previous molecular phylogenetic study Maximum parsimony analyses of 20 fruit structural characters resulted in a generally poorly resolved strict consensus tree, yet one whose major clades matched those revealed previously Angelica apaensis and Heracleum xiaojinense are best treated as the single species Angelica apaensis within Angelica s s All remaining Heracleum species share a highly lignified hypendocarp and a lignified endocarp, vascular bundles in marginal wings situated in the middle of the wing, and a commissure width the same as the mericarp width These Heracleum species are recognized in four major clades with the following fruit structural features: (1) Heracleum s s, having non-septate, clavate dorsal vittae that do not extend to the bottom of the see
TL;DR: Biogeographic analysis suggests a New World origin for the Calypsoinae subtribe, with two major shifts to the Old World and one shift back to the New World.
Abstract: Calypsoinae are a small, largely temperate subtribe that are diverse with respect to trophic strategy (many species have an unusual winter leaf and several are leafless) and pollinium stalk morphology. Here we sought to re-evaluate the placement of Yoania and recently proposed genera and to examine trophic strategy, pollinium stalk type, and geographic distribution in a phylogenetic context. We analyzed ITS and matK sequences from all accepted genera using maximum likelihood and parsimony on individual and combined data sets. The only supported disagreement among trees was between the combined ML and parsimony analyses for the placement of Dactylostalix and Ephippianthus; the trees from one analysis reflected the nuclear pattern, while the other resembled the plastid pattern. A group of genera related to Calypso and a group related to Corallorhiza were resolved. Yoania is closely related to Calypso; the recently proposed Yunorchis is a species of Yoania, while Didiciea is part of Tipularia. Examining leaf morphology on the tree revealed two originations of the winter leaf morphology and four losses of leaves (and shifts to mycoheterotrophy). Pollinium stalks evolved in three directions, two of which resulted in epidermally-derived stalks (tegulae) and one that comprises the entire rostellum (a hamulus). Biogeographic analysis suggests a New World origin for the subtribe, with two major shifts to the Old World and one shift back to the New World.
TL;DR: A phylogenetic analysis of 11 species of Caamembeca based on nrITS, matK, thetrnL intron, and trnL-trnF intergenic spacer is presented, providing an improved understanding of the genus.
Abstract: Caamembeca (Polygalaceae) is a genus of 13 species endemic to South America. The genus is morphologically distinctive, e.g. supported by the putative morphologic synapomorphy of paired glands in a stipular position and on the rachis. However, its monophyly has not been robustly tested as only four species have been included in previous phylogenetic analyses. We present a phylogenetic analysis of 11 species based on nrITS, matK, the trnL intron, and trnL-trnF intergenic spacer. Relationships among Caamembeca species are discussed, and three new combinations are made, Caamembeca amazonensis, Caamembeca autranii, and Caamembeca formosa, providing an improved understanding of the genus.
TL;DR: This research clarifies species boundaries within this challenging group, and is the first to use molecular phylogenetic data to support hybridization as an evolutionary force within the S. cernua species complex.
Abstract: Two major obstacles to quantifying biodiversity are reticulate evolution and the evolution of genetically distinct but morphologically overlapping cryptic species. The Spiranthes cernua species complex (Orchidaceae) has defied satisfactory species delineation, often described as intractable, due to morphological variability within species, overall morphological similarity between species, possible cryptic speciation, and suspected hybridization. Weutilized low copy nuclear, nuclear ribosomal, and chloroplast molecular phylogenetic datasets, in addition to expansive field and herbarium research, to clarify long-standing questions regarding species boundaries within the S. cernua species complex. Our results justify: 1) narrowing the concept of S. cernua; 2) the description of a new cryptic species, Spiranthes arcisepala; 3) the description of a new geographically restricted species of cryptic and ancient hybrid origin, Spiranthes niklasii (S. cernua × S. ovalis); 4) a new combination for a biogeographically specific cryptic species of ancient hybrid origin, Spiranthes incurva (S. cernua×S. magnicamporum); and 5) the description of a new localized hybrid, Spiranthes ×kapnosperia (S. cernua × S. ochroleuca). We also propose formal synonymization of federally endangered Spiranthes parksii under S. cernua s. s. Our research clarifies species boundaries within this challenging group, and is the first to use molecular phylogenetic data to support hybridization as an evolutionary force within the S. cernua species complex.
TL;DR: A new species of Microlicia (Melastomataceae) from Goiás state is described and illustrated, and a discussion on leaf microscopy is provided, and the presence of a bright golden cuticle covering the glandular trichomes is reported here for the first time in Micro Licia.
Abstract: A new species of Microlicia (Melastomataceae) from Goias state is described and illustrated, and a discussion on leaf microscopy is also provided. Microlicia chrysoglandulosa sp. nov. resembles M. martiana, M. psammophila, and M. tenuifolia by the slender and fastigiate branches, triangular sepals, and stamens with tetrasporangiate thecae. However, it differs by the remarkable indumentum of spherical short-stalked glandular trichomes on the internodes, abaxial leaf surfaces andmargins, pedicels, hypanthium and sepals. The presence of a bright golden cuticle covering the glandular trichomes is reported here for the first time in Microlicia.
TL;DR: Information on the rare and poorly known species of the genus Sesvium is compiled and issues concerning species concepts in Sesuvium, which impede species identification are addressed.
Abstract: Sesuvium and Cypselea are closely related succulent genera within the Sesuvioideae (Aizoaceae). Since Cypselea is nested in Sesuvium in molecular studies and both genera share traits separating them from other members of the subfamily, we propose to include Cypselea in Sesuvium. Sesuvium (incl. Cypselea) comprises 14 species and is distributed worldwide with centres of diversity in southern Africa and North and Central America. Sesuvium comprises erect to procumbent herbs with opposite leaves that often bear conspicuous sheath-like lateral appendages on the petioles (pseudostipules). These and the many-seeded capsules are diagnostic traits, separating Sesuvium from the closely related genera Trianthema and Zaleya. Sesuvium is usually found in coastal or otherwise saline areas and is phylogenetically divided into an African (5 spp.) and an American lineage (9 spp.). While all African species are C4 plants, the American lineage also comprises a derived C3 lineage, which includes the cosmopolitan species S. portulacastrum. Some floras provide descriptions and keys for locally relevant species, but currently no comprehensive taxonomic treatment is available for Sesuvium. In this paper, a key and descriptions for all species are provided. Furthermore, we compile information on the rare and poorly known species of the genus and address issues concerning species concepts in Sesuvium, which impede species identification. The inclusion of Cypselea in Sesuvium leads to three new combinations: Sesuvium humifusum, Sesuvium mezianum and Sesuvium rubriflorum.
TL;DR: A comprehensive sampling of Indian and Australian species formed three well-supported clades based on analyses of molecular sequence data and concluded that Corynandra is not related to the Australian species as discussed by the authors.
Abstract: Novel molecular data and morphological studies have provided support for the segregation of numerous genera from Cleome s. l. (Cleomaceae). Corynandra has been proposed as a segregate genus including Indian and Australian species based on floral and seed morphology. Contrasting seed coat micro-morphology between Indian and Australian species included in Corynandra raised questions over the monophyly of that genus concept. Relationships among the Indian and Australian species remain unclear due to limited sampling in previous molecular analyses. We expanded the sampling of taxa from India and Australia in order to clarify relationships between these species and the circumscription of Corynandra. Comprehensive sampling of Indian and Australian species formed three well-supported clades based on analyses of molecular sequence data and we conclude that Corynandra is not related to the Australian species. The genus Arivela Raf. is reinstated for the majority of Australian species. The new genus Areocleome is described to accommodate the unusual Australian C4 species Cleome oxalidea. The following new combinations are made: Areocleome oxalidea, Arivela arenitensis, Arivela bundeica, Arivela cleomoides, Arivela insolata, Arivela kenneallyi, Arivela limmenensis, Arivela linophylla, Arivela lophosperma, Arivela microaustralica, Arivela tetrandra, Arivela uncifera, Corynandra aspera, and Corynandra simplicifolia. Arivela microphylla is raised to species level and provided with a new combination.
TL;DR: Ancestral state reconstruction of pollination systems among Old World Ruellia suggest a minimum of two transitions from short-tongued insect pollination to nocturnal moth pollination, one from Short-Tongued Insect to bird pollination and one reversal fromNocturnal moths pollination back to short- tongued insects pollination.
Abstract: The genus Ruellia (Acanthaceae) consists of some ca. 350 species that are concentrated in tropical and subtropical regions of the world. Old World Ruellia have never been the focus of explicit phylogenetic study, yet comprise the earliest diverging lineages in the genus and contain upwards of 100 species. We sampled 52 accessions representing 29 OW species of Ruellia for phylogenetic analysis. Results yielded five clades that were strongly supported and marked by morphological synapomorphies. Analyses additionally recovered a newly recognized lineage within the tribe Ruellieae, a small radiation of plants in the deserts of Namibia and Angola, and the name Dinteracanthus is available for reinstatement. Divergence time analysis using a primary fossil calibration revealed relatively young estimates for crown ages of all five clades of OWRuellia (2.5 Ma - 630,000 ypb) as well as for Dinteracanthus (2.0 Ma). Ancestral state reconstruction of pollination systems among OW Ruellia suggest a minimum of two transitions from short-tongued insect pollination to nocturnal moth pollination, one from short-tongued insect to bird pollination, and one reversal from nocturnal moth pollination back to short-tongued insect pollination. We formally delimit the five clades of OW Ruellia as sections and present a key to aid in their identification: sect. Eusiphon, sect. Dipteracanthus, sect. Madagasikara, sect. Pseudoruellia, and sect. Discifolia. We provisionally treat 77 of 97 species of OW Ruellia among these five sections, with the remaining names considered to be unresolved.
TL;DR: The genus Rorida is strongly supported as monophyletic by molecular data and is also morphologically very distinctive, with simple leaves, four stamens, and triangular, very shortly clawed, dimorphic petals, appendaged at the base.
Abstract: The genus Rorida J.F. Gmel. is resurrected for Cleome L. sect. Thylacophora Franch. within the non-monophyletic Cleome. Rorida is strongly supported as monophyletic by molecular data and is also mo ...
TL;DR: Phylogenetic analyses of sequence data recovered six major clades but sects, and Psammiris, Pseudoregelia, and Regelia, are not monophyletic as currently circumscribed.
Abstract: Subgenus Iris is wholly Eurasian, distributed in temperate regions from northeastern China to eastern and southern Europe where they occur in mountainous and/or dry rocky sites from near sea level to elevations of 4,500 m. These species have an easily discerned synapomorphy, a multicellular beard on each petaloid sepal. Currently two large and relatively well known and four smaller and less known sections are recognized in the subgenus. This study investigated the monophyly of circumscribed sections and relationships among these sections. Seventy-one taxa, representing each of the six sections and about 80% of the recognized species in subgen. Iris, and 11 outgroup taxa were included in the study. Also included were five Asian species that share some morphological characteristics with subgen. Iris but are typically considered in other subgenera. Phylogenetic analyses of sequence data recovered six major clades but sects. Psammiris, Pseudoregelia, and Regelia, are not monophyletic as currently cir...
TL;DR: Divergent topologies suggest chloroplast capture of T. chinensis by Japanese T. sieboldii and Ulleungdo hemlocks are distinct from other northeastern Asian species in leaf and cone morphology and phenologically in common-garden observations, and are described as a new species, T. ulleungensis.
Abstract: Species delimitation in Pinaceae is often challenged by limited morphological differentiation and introgression. In Tsuga (hemlocks), species delimitation has been most challenging among northeastern Asian taxa, where the species are weakly marked morphologically and range in number from three to five in previous studies. Two low-copy nuclear four-coumarase-ligase (4CL) genes andmorphology strongly support a clade of the Japanese endemic T. diversifolia and T. sieboldii from Japan and Ulleung island (Ulleungdo) in Korea. This clade is here referred to as the oceanic hemlocks. 4CL strongly supports a sister-group relationship of the widespread northeastern Asian T. chinensis and eastern North American T. caroliniana. In contrast, chloroplast genomes, which are markedly reduced in Tsuga and relatives, strongly support Japanese T. sieboldii as sister to T. chinensis and moderately support T. caroliniana as sister to a clade of T. diversifolia and hemlocks fromUlleungdo. These divergent topologies suggest chloroplast capture of T. chinensis by Japanese T. sieboldii. Ulleungdo hemlocks are distinct from other northeastern Asian species in leaf and cone morphology and phenologically in common-garden observations. We therefore describe these hemlocks as a new species, T. ulleungensis.
TL;DR: Cyphostemma dehongense and C. auriculatum are morphologically similar, but differ in ovary size, style length, and fruit size, and molecular data were used to determine the phylogenetic position of the new species and the newly recorded taxon.
Abstract: A new species, Cyphostemma dehongense, is described from Dehong, Yunnan, China, and C. auriculatum is newly recorded from Vietnam. These are the first records of the genus Cyphostemma from the two countries, extending both the easternmost and northernmost distribution limit of Cyphostemma. Through field explorations over two years, we discovered four populations of C. dehongense and collected specimens of the species with both flowers and fruits. Cyphostemma dehongense and C. auriculatum are morphologically similar, but differ in ovary size, style length, and fruit size. In addition to morphological comparisons, molecular data were used to determine the phylogenetic position of the new species and the newly recorded taxon. Ten nucleotide variation sites were detected between C. dehongense and C. auriculatum based on five chloroplast loci (atpB-rbcL, rps16, trnC-petN, trnH-psbA, and trnL-F) and the nuclear ribosomal internal transcribed spacer (ITS). An identification key is provided for the three species of Cyphostemma from Asia.
TL;DR: Stemodia cipoensis is similar to S. harleyi, S. lobata, and S. stellata, being characterized by the presence of long, stiff, curved, eglandular trichomes and has been assessed as CE (critically endangered) under criteria B1ab(ii) and B2ab(iii), following IUCN guidelines.
Abstract: The Serra do Cipo, part of the central portion of the Espinhaco Range in Minas Gerais, Southeast Brazil, is known to have been extensively investigated over the past three decades, especially because of the “Flora da Serra do Cipo” project Nevertheless, some areas have been poorly collected as the efforts were largely concentrated near the roads Various new species, in several families, have been recently discovered in the campos rupestres of the Serra do Cipo Here we report the discovery of a new species of Stemodia (Plantaginaceae) from the northwestern slopes We describe and illustrate the new species based on morphological and micro-morphological evidence, provide information on its taxonomy, habitat, geographical distribution, and conservation status, along with a key to distinguish it from the related species Stemodia cipoensis is similar to S harleyi, S lobata, and S stellata, being characterized by the presence of long, stiff, curved, eglandular trichomes It has been assessed as
TL;DR: The first comprehensively sampled phylogeny of American and African Senegalia is presented, however Asian species are not sampled, suggesting a more complicated evolutionary history of the genus than previously considered, including probable transatlantic dispersal events.
Abstract: Senegalia is a genus of the legume family (Leguminosae: Mimosoideae) that has a pantropical distribution with centers of diversity in Brazil, Mexico and southern Africa. The genus is characterized by plants having bipinnate leaves, presence of petiolar nectaries, prickles on the branches, and pollen grains arranged in polyads with 16 grains. Morphology is an important tool for identification of Senegalia species, but it is not sufficient to resolve all taxonomic issues and elucidate the evolutionary history of this genus. Prior molecular analyses of Mimosoideae have lacked breadth of samplingwithin Senegalia, leavingmany relationships uncertain, particularly the relationship among Brazilian species and other members of the genus. The aim of this study was to identify Senegalia s. s. lineages that contain Brazilian species, and to investigate the relationship of these species with non-Brazilian Senegalia species. We present the first comprehensively sampled phylogeny of American and African Senegalia, however Asian species are not sampled.We sequenced four plastid and one nuclear DNA (ITS) regions for 125 samples of 59 Senegalia and one Parasenegalia species. Both Bayesian andmaximum likelihood analyses were performed.Neither the American or African species form monophyletic lineages. The lack of monophyly of these groups suggests a more complicated evolutionary history of the genus than previously considered, including probable transatlantic dispersal events.
TL;DR: A molecular phylogenetic analysis of the major genera of the American species of Acacia s.
Abstract: Studies have shown that the genus Acacia Miller s. l. is polyphyletic, consisting of at least seven distinct groups of species. One of these major groups, Senegalia s. l., was also determined to be non-monophyletic. This has resulted in the recent recognition of two new genera, Parasenegalia Seigler and Ebinger, consisting of seven species, and Pseudosenegalia Seigler and Ebinger, consisting of two species. A molecular phylogenetic analysis of these genera and sister taxa, especially Mariosousa Seigler and Ebinger, determined that each is monophyletic, although Parasenegalia visco (Lorentz andGrisebach) Seigler and Ebinger is weakly supported as sister to the rest of Parasenegalia. Pseudosenegalia is sister to the rest of the ingroup, however the node containing Parasenegalia, Mariosousa, and the remaining ingroup grade of Ingeae and Acacia s. s. is poorly supported. These results provide a phylogenetic resolution for the major genera of the American species of Acacia s. l., but full phylogenetic...
TL;DR: This article provides a key to separate the six species included in series Tricolores, with updated species descriptions, synonymy, typification, distribution, and illustrations of characteristics (i.e. stamens, seeds, calyces).
Abstract: Lycianthes tricolor was first described (in Solanum) in 1813, based on a painting from the Sesse and Mocino expedition to New Spain. In 1904, the similar L. arrazolensis was described (also in Solanum), and since that time, plant collectors have had difficulty separating L. tricolor from L. arrazolensis. Since then four more species allied to L. tricolor and L. arrazolensis have been described: L. surotatensis in 1948, L. jalicensis in 1998, and more recently L. venturana and L. michaelneei in 2014. This article provides a key to separate the six species included in series Tricolores, with updated species descriptions, synonymy, typification, distribution, and illustrations of characteristics (i.e. stamens, seeds, calyces). We include discussion of specimens that belong in series Tricolores, but are difficult to place and require additional study, as well as the uncertain status of L. arrazolensis var. patentipila.
TL;DR: An additional phylogenetic analysis of Elatine found that both polyploids probably are allopolyploids, in a pattern consistent with the placement of the putative parental taxa in previous phylogenetic analyses of ITS, matK/trnK, and rbcL sequence data.
Abstract: The study of hybridization in aquatic plants is complicated by rarity of flower production, absence of roots, and asexuality. Elatine is a cosmopolitan genus of aquatic flowering plants with about 25 species worldwide. Historically, there has been little concern regarding hybridization in the genus due to the prevalence of autogamy (i.e. self-pollination), which potentially limits xenogamous pollen transfer among the species. Two morphologically complex species (Elatine hexandra and E. americana) are the only known polyploids in the genus. In previous phylogenetic analyses, both species resolved incongruently in gene trees obtained from nuclear (ITS) versus plastid (matK/trnK and rbcL) regions. Suspecting that the phylogenetic incongruence might be a consequence of past hybridization events, we tested that hypothesis by conducting an additional phylogenetic analysis of Elatine, which incorporated sequences from a low copy nuclear gene (phyC). Elatine hexandra and E. americana were the only Elatin...
TL;DR: The species comprising the African Asclepias complex cannot be readily partitioned into monophyletic genera, and the approximately unbiased test did not reject the monophyly of the African species of As Clepias nor the segregate African genera.
Abstract: We infer phylogenetic relationships and test the monophyly of genera of the African Asclepias complex with three non-coding plastid DNA regions, rpl16 intron, trnC-rpoB spacer, and trnS-G spacer/trnG intron. We find that Asclepias (Trachycalymma) pseudofimbriata forms a polytomy with a clade of all other sampled African species of Asclepias s. l. and a clade of the American Asclepias s. s. Asclepias s. l. and the African species classified in Asclepias are both paraphyletic groups since segregate genera are all nested among species of African Asclepias. Most segregate genera are not monophyletic, i.e. Gomphocarpus, Pachycarpus, Stathmostelma, Xysmalobium, Schizoglossum, and Aspidoglossum; however, Glossostelma is monophyletic. Due in part to low levels of divergence in the sampled plastid markers, the approximately unbiased test did not reject the monophyly of the African species of Asclepias nor the segregate African genera, although the monophyly of Asclepias circumscribed to include American a...
TL;DR: Field work conducted over the past fifteen years in the Sierra Juárez of Oaxaca, Mexico, has resulted in three new species of grammitid ferns and a new state distribution record, including Ceradenia margaritata, which was previously known in Mexico from Chiapas.
Abstract: Field work conducted over the past fifteen years in the Sierra Juarez of Oaxaca, Mexico, has resulted in three new species of grammitid ferns and a new state distribution record. Two of the new species, Ceradenia sacksii and Lellingeria labiakii, are known only from the vicinity of Cerro Pelon and Humo Chico, in the Sierra Juarez. The third new species, Mycopteris martiniana, is also known from similar habitats in the states of Mexico and Veracruz. All three species are illustrated with line art and photographs and distinguished from their most similar relatives. The new record, Ceradenia margaritata, was previously known in Mexico from Chiapas. With these new additions, 37 species of grammitid ferns distributed in ten genera are now known from Mexico. Twenty eight of these species occur in Oaxaca, which remains the Mexican state with the overall highest diversity of ferns.
TL;DR: The phylogeny of Cochlospermaceae is reconstructed to evaluate the monophyly of the family and its two genera, to resolve interspecific relationships, and to interpret patterns of morphological evolution.
Abstract: Cochlospermaceae (Malvales) is a small family of two genera, Amoreuxia and Cochlospermum. Cochlospermum has a pantropical distribution with species present in Mexico, Central and South America, the West Indies, Africa, India, Southeast Asia, and northern Australia, whereas Amoreuxia has a more restricted distribution in the Americas. Amoreuxia is comprised of four herbaceous species, and Cochlospermum has seven tree species and five that are suffrutescent subshrubs. The two genera also differ in floral symmetry, corolla coloration patterns, and stamen morphology. The goals of this study were to reconstruct the phylogeny of Cochlospermaceae to evaluate the monophyly of the family and its two genera, to resolve interspecific relationships, and to interpret patterns of morphological evolution. In addition, a minor goal was to examine its relationship to sister families, such as Bixaceae, a family in which Cochlospermaceae has been variously placed. Phylogenetic analyses were carried out using DNA se...