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Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking noncoding regions, gene tree/species tree methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic, edaphic, and morphological diversity in the group. We found that the combination of exons and flanking noncoding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple evolutionary origins of bee pollination from ancestral hawkmoth pollination, edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively reconstruct the recalcitrant history of a rapid radiation. [Gypsum endemism; Oenothera sect. Calylophus; Onagraceae; phylogenomics; pollinator shift; recent radiation; target enrichment.]

—Molecular and morphological evidence supports a new species in the genus Antiphytum from the Sierra Madre del Sur, in the state of Guerrero, Mexico, here described as Antiphytum brevicalyx. This species is unique in the genus by possessing a calyx shorter than the corolla tube at anthesis; it is similar to A. floribundum in inflorescence arrangement, but differs from that species in lacking a basal leaf rosette and having appendages on the corolla throat. According to phylogenetic analysis of nuclear ITS and plastid ndhF-rpl32 sequences representing seven of the eight North American species of the genus besides the proposed new species, accessions of A. brevicalyx form a well-defined clade within Antiphytum, corroborating its distinctive morphology. However, the analyses do not resolve the phylogenetic position of A. brevicalyx within the genus.

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking non-coding regions, summary coalescent methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic and morphological diversity in the group. We found that the combination of exons and flanking non-coding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple origins of the evolution of bee pollination from ancestral hawkmoth pollination, the evolution of edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively address a relatively common but recalcitrant problem in evolutionary biology.

Premise of the study The Caryophyllales contain ~12,500 species and are known for their cosmopolitan distribution, convergence of trait evolution, and extreme adaptations. Some relationships within the Caryophyllales, like those of many large plant clades, remain unclear, and phylogenetic studies often recover alternative hypotheses. We explore the utility of broad and dense transcriptome sampling across the order for resolving evolutionary relationships in Caryophyllales. Methods We generated 84 transcriptomes and combined these with 224 publicly available transcriptomes to perform a phylogenomic analysis of Caryophyllales. To overcome the computational challenge of ortholog detection in such a large data set, we developed an approach for clustering gene families that allowed us to analyze >300 transcriptomes and genomes. We then inferred the species relationships using multiple methods and performed gene-tree conflict analyses. Key results Our phylogenetic analyses resolved many clades with strong support, but also showed significant gene-tree discordance. This discordance is not only a common feature of phylogenomic studies, but also represents an opportunity to understand processes that have structured phylogenies. We also found taxon sampling influences species-tree inference, highlighting the importance of more focused studies with additional taxon sampling. Conclusions Transcriptomes are useful both for species-tree inference and for uncovering evolutionary complexity within lineages. Through analyses of gene-tree conflict and multiple methods of species-tree inference, we demonstrate that phylogenomic data can provide unparalleled insight into the evolutionary history of Caryophyllales. We also discuss a method for overcoming computational challenges associated with homolog clustering in large data sets.

The conceptualization and coding of characters is a difficult issue in phylogenetic systematics, no matter which inference method is used when reconstructing phylogenetic trees or if the characters are just mapped onto a specific tree. Complex characters are groups of features that can be divided into simpler hierarchical characters (reductive coding), although the implied hierarchical relational information may change depending on the type of coding (composite vs. reductive). Up to now, there is no common agreement to either code characters as complex or simple. Phylogeneticists have discussed which coding method is best but have not incorporated the heuristic process of reciprocal illumination to evaluate the coding. Composite coding allows to test whether 1) several characters were linked resulting in a structure described as a complex character or trait or 2) independently evolving characters resulted in the configuration incorrectly interpreted as a complex character. We propose that complex characters or character states should be decomposed iteratively into simpler characters when the original homology hypothesis is not corroborated by a phylogenetic analysis, and the character or character state is retrieved as homoplastic. We tested this approach using the case of fruit types within subfamily Cinchonoideae (Rubiaceae). The iterative reductive coding of characters associated with drupes allowed us to unthread fruit evolution within Cinchonoideae. Our results show that drupes and berries are not homologous. As a consequence, a more precise ontology for the Cinchonoideae drupes is required.

Understanding the evolution of biodiversity on Earth is a central aim in biology. Currently, various disciplines of science contribute to unravel evolution at all levels of life, from individual organisms to species and higher ranks, using different approaches and specific terminologies. The search for common origin, traditionally called homology, is a connecting paradigm of all studies related to evolution. However, it is not always sufficiently taken into account that defining homology depends on the hierarchical level studied (organism, population, and species), which can cause confusion. Therefore, we propose a framework to define homologies making use of existing terms, which refer to homology in different fields, but restricting them to an unambiguous meaning and a particular hierarchical level. We propose to use the overarching term "homology" only when "morphological homology," "vertical gene transfer," and "phylogenetic homology" are confirmed. Consequently, neither phylogenetic nor morphological homology is equal to homology. This article is intended for readers with different research backgrounds. We challenge their traditional approaches, inviting them to consider the proposed framework and offering them a new perspective for their own research. ispartof: SYSTEMATIC BIOLOGY vol:68 issue:5 pages:767-780 ispartof: location:England status: published

Antecedentes y Objetivos: El número de especies del género Rogiera aún es debatible, varía entre 11 y 20 dependiendo de los criterios utilizados por diferentes autores en su delimitación. México está considerado como el centro de riqueza de este género con hasta 14 especies reconocidas que se distribuyen principalmente en bosque mesófilo de montaña y selva alta perennifolia.Métodos: El material botánico colectado como parte de un estudio florístico y fitogeográfico de la porción noroeste del municipio Metztitlán, Hidalgo, se comparó con ejemplares de especies de Rogiera depositados en las colecciones ENCB, F, FCME, MEXU y MO. Después de revisar los tipos nomenclaturales y protólogos de todas las especies de Rogiera, se determinó que este material corresponde a una especie nueva.Resultados clave: Se describe e ilustra Rogiera metztitlensis, una especie nueva de la zona árida de Metztitlán, Hidalgo, México. Esta especie tiene similitud morfológica con Rogiera amoena, R. cordata y R. ehrenbergii en la orientación de la estípula al madurar, (excepto en R. ehrenbergii) tamaño y color de las flores. Difiere de éstas por ser un arbusto de hasta 1 m de alto, las estípulas más pequeñas, de 3 a 4 mm de largo, la garganta de la corola con anillo de tricomas blancos y las semillas sin alas.Conclusiones: Rogiera metztitlensis es endémica de Hidalgo, se desarrolla en hábitats áridos, en contraste con los hábitats húmedos en los que predomina el resto de las especies de este género.

Antecedentes y Objetivos: Loganiaceae es un grupo de plantas tropicales que se han estudiado escasamente en México. Algunos de sus taxones son poco conocidos en cuanto a su taxonomía y distribución, como el caso del género Mitreola, en el que además algunas de sus especies tienen problemas nomenclaturales. Este trabajo presenta una revisión taxonómica de Mitreola petiolata y resuelve los problemas nomenclaturales que ha tenido a lo largo de los años.Métodos: Se revisaron especímenes en diferentes herbarios, literatura especializada para la obtención de descripciones y claves taxonómicas, número de especies del género y su distribución; así como la circunscripción y problemas nomenclaturales del taxon. Para la obtención de los datos palinológicos, se acetolizó material de flores maduras y se revisó en el microscopio electrónico de barrido. A partir de los datos obtenidos se obtuvo una evaluación de la situación de conservación.Resultados clave: Mitreola petiolata tiene una distribución pantropical y es la única especie del género presente en el país. La especie se extiende desde Tamaulipas y Sinaloa hasta la Península de Yucatán. A pesar de la variación morfológica de estructuras como las hojas o los lóbulos de la cápsula, los caracteres de importancia taxonómica (inflorescencias dicotómicas, flores subsésiles y estambres insertos cerca de la base de la corola) se mantienen constantes. Se proporciona una revisión para M. petiolata, una clave dicotómica, datos sobre su distribución y estado de conservación en el país. Se presenta información detallada sobre la micromorfología de los granos de polen, la primera hecha para la especie. Se sugiere la categoría de preocupación menor por su amplia distribución.Conclusiones: La constante revisión y curación de las colecciones biológicas mantiene actualizado el conocimiento de los taxones. Tal es el caso de M. petiolata, para la cual se proporciona una actualización de su sistemática, distribución y estado de conservación.

ResumenSe estudió la anatomía de corteza y madera de 42 especies de 8 tribus de Rubiaceae con la finalidad de evaluar si los caracteres anatómicos permiten la separación de las especies de los géneros presentes en México y si hay caracteres relacionados con el ambiente donde viven o su hábito. El fenograma mostró 2 grupos que corresponden a la madera tipo I y II sensu Koek-Noorman. No todas las especies de Bouvardia ni de Psychotria se agrupan en su respectivo género y Notopleura anomothyrsa es diferente del resto por tener fibrotraqueidas septadas y punteaduras intervasculares escalariformes. El grupo de Arachnothryx, Chione, Exostema, Hintonia y Randia con madera tipo I presenta ritidoma, bandas de esclereidas y 3 tipos de cristales en el floema; son árboles o arbustos de selva baja caducifolia y bosque mesófilo. El grupo con madera tipo II tiene una peridermis, endodermis, grupos de fibras/esclereidas y rafidios en el floema; son arbustos de selva alta perennifolia, baja caducifolia, bosque mesófilo y de pino-encino. Los anillos de crecimiento en estas especies sugieren estar asociados con aspectos fenológicos y las condiciones del hábitat, pero no así el diámetro y densidad de los vasos que parecen tener una fuerte señal filogenética.AbstractWood and bark anatomy of 42 species of Rubiaceae from 8 tribes were studied with the aim to assess whether the anatomical characters allow separation of species belonging to the different genera in Mexico and whether characters are related to the environment where they live or their habit. Two groups resulted in the phenogram, corresponding to wood type I and II sensu Koek-Noorman. Not all species of Bouvardia and Psychotria grouped in their respective genera and Notopleura anomothyrsa is different from the other species having fibertracheids and scalariform intervascular pits. The Arachnothryx, Chione, Exostema, Hintonia and Randia group with wood type I presents rhytidome, bands of sclereids and 3 types of crystals in the phloem, and are trees or shrubs of the seasonal dry forest and the cloud forest. The group with wood type II has a single periderm, endodermis, groups of fibers/sclereids and raphides in the phloem, and are shrubs of the tropical rainforest, seasonal dry forest, cloud forest, and pine-oak forest. Growth rings in these species may be associated with phenology and habitat conditions, but vessel diameter and density appear to have a strong phylogenetic signal.

Structural data were combined with trnL-F and internal transcribed spacer sequences from other studies and with new sequences representing ten additional species to clarify the phylogenetic relationships of Rhus s.s. These data indicate that Rhus s.s and both subgenera, Rhus and Lobadium, are monophyletic. The genus Rhus is supported as monophyletic by the presence of red glandular hairs on the berries and inflorescence axis, cilia on the sepals and glands on the leaf blades. Subgenus Rhus can be identified by the presence of more than seven resin channels in the petiole, weakly percurrent tertiary veins and a type I vascular system in the mid-vein. Subgenus Lobadium is characterized by the presence of short bracteoles and pedicels. This subgenus is divided into four sections, Lobadium, Rhoeidium, Styphonia and Terebinthifolia. Section Lobadium has trifoliate leaves; section Rhoeidium is monotypic, including only Rhus microphylla; section Styphonia is supported by five synapomorphies, including an incomplete marginal vein, fibres in the petiole, a thick cuticle, two layers of palisade parenchyma and prismatic crystals in the mesophyll; and section Terebinthifolia has gelatinous xylary fibres in the petiole. Hypotheses about the evolutionary changes of these characters are presented based on the cladograms. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176, 452–468.

ResumenSe describen e ilustran 2 especies nuevas de la familia Rubiaceae de la sierra de los Tuxtlas al sur de Veracruz, México: Arachnothryx pumae (Guettardeae) y Hoffinannia altipetens (Hamelieae). La especie A. pumae se parece morfológicamente a A. buddelioides y a A. villosa; se distingue por la estípula triangular de 2.0 a 3.0mm de largo, la inflorescencia laxa, brácteas florales de 3.0mm de largo y 1.0mm de ancho, el fruto 10-costillado y la semilla plegada; la especie H. altipetens se caracteriza por los cistolitos en las nervaduras de las hojas, inflorescencias con 2 a 6 ejes por nodo y frutos blancos.AbstractTwo new species of Rubiaceae are described from Sierra de los Tuxtlas in southern Veracruz, Mexico: Arachnotrhyx pumae (Guettardeae) and Hoffmannia altipetens (Hamelieae). Arachnotrhyx pumae is similar to A. buddleioides and A. villosa, but it differs by the triangular stipules, 2.0 to 3.0mm long, lax inflorescence, floral bracts of 3.0mm long and 1.0mm width, 10-ribbed fruit and the folded seed. Hoffmannia altipetens is characterized by cystoliths on the leaf veins, inflorescences with 2 to 6 axis per node and white fruits.

Fil: Arias, Salvador. Universidad Nacional Autónoma de México; México Fil: Berendsohn, Walter G.. Freie Universität Berlin; Alemania Fil: Borsch, Thomas. Freie Universität Berlin; Alemania Fil: Flores Olvera, Hilda. Universidad Nacional Autónoma de México; México Fil: Ochoterena, Helga. Universidad Nacional Autónoma de México; México Fil: von Mering, Sabine. Freie Universität Berlin; Alemania Fil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina

A cladistic analysis including for the first time all taxa of Anulocaulis, five species and four varieties, is presented. Sixteen potentially related taxa classified within Boerhavia, Commicarpits, Cyphomeris, Nyctaginia, and Okenia were used as outgroup to test the monophyly and phylogenetic position of Anulocaulis; Mirabilis glabrifolia was used to root the tree. Forty-one characters were included in the matrix, which was analyzed using the parsimony criterion. Our results are in partial agreement with previous studies using molecular data. Here, the monophyly of Anulocaulis is corroborated, but the sister group remains ambiguous depending on whether the multistate characters are treated as additive or nonadditive. In the first case, Anulocaulis is sister to Nyctaginia-Okenia, while in the second it is sister to Boerhavia anisophylla. The morphological characters which have been used in the traditional taxonomy and classification of the genus are analyzed and discussed under a phylogenetic cont...

Kohautia Cham. & Schltdl. belongs to the predominantly herbaceous Rubiaceae tribe Spermacoceae. Species of Kohautia can easily be distinguished from other Spermacoceae by their monomorphic short-styled flowers in which anthers and stigma are included in the corolla tube, with the stigma always positioned below the anthers. Mainly because of this unique floral morphology, Kohautia was considered to be a distinct genus. Molecular data (atpB-rbcL, petD, rps16, trnL-trnF, ETS, ITS) confirm that the genus is biphyletic. Two distantly related clades correspond to the subgenera Kohautia and Pachystigma Bremek. A similar type of floral organisation thus seems to have evolved twice independently, resulting in similar, but distantly related lineages. In order to translate the biphyletic nature of Kohautia into a formal classification, the two subgenera are recognized at generic level. A substitute name, Cordylostigma Groeninckx & Dessein is proposed for K. subg. Pachystigma because of the existence of Pachystigma Hochst. in the Rubiaceae tribe Vanguerieae. Floral, pollen and seed characters were studied to morphologically characterize Kohautia s.str. and Cordylostigma. By optimizing pollination syndromes and pollen characters onto the molecular phylogeny, we investigated pollination shifts and pollen evolution within the two genera. Detailed floral morphological studies show that the nectar guides in the psychophilous species of Kohautia s.str. and Cordylostigma evolved in different ways but result in the same visual effect.

Algorithms that minimize putative synapomorphy in an alignment cannot be directly implemented since trivial cases with concatenated sequences would be selected because they would imply a minimum number of events to be explained (e.g., a single insertion/deletion would be required to explain divergence among two sequences). Therefore, indirect measures to approach parsimony need to be implemented. In this paper, we thoroughly present a Global Criterion for Sequence Alignment (GLOCSA) that uses a scoring function to globally rate multiple alignments aiming to produce matrices that minimize the number of putative synapomorphies. We also present a Genetic Algorithm that uses GLOCSA as the objective function to produce sequence alignments refining alignments previously generated by additional existing alignment tools (we recommend MUSCLE). We show that in the example cases our GLOCSA-guided Genetic Algorithm (GGGA) does improve the GLOCSA values, resulting in alignments that imply less putative synapomorphies.

We examined 532 specimens representing eight species of Didymaea (Rubiaceae) to describe their leaf architecture. Characters observed in the herbarium specimens and cleared leaves were leaf base, apex, and margin; trichome type and distribution; vein orders from primary to higher order veins, veinlets, and ultimate marginal vein. Six morphometric variables were analyzed using variance and principal component analysis to identify which characters are useful to distinguish species. Most of the species present brochidodromous venation pattern, except D. hispidula, which has eucamptodromous venation pattern; Didymaea floribunda is unique in having cylindrical and bicellular trichomes. Principal component analysis revealed that 78% of the total variation is mainly related to leaf maximum width. Variance analysis showed significant differences between D. microflosculosa and the other species. Architectural features were useful for differentiating all the species, and an identification key for the species of Didymaea based only on leaf characters is presented.

In its current circumscription, the herbaceous tribe Spermacoceae s.l. (Rubiaceae, Rubioideae) unites the former tribes Spermacoceae s. str., Manettieae, and the Hedyotis–Oldenlandia group. Within Spermacoceae, and particularly within the Hedyotis–Oldenlandia group, the generic delimitations are problematic. Up until now, molecular studies have focused on specific taxonomic problems within the tribe. This study is the first to address phylogenetic relationships within Spermacoceae from a tribal perspective. Sequences of three plastid markers (atpB-rbcL, rps16, and trnL-trnF) were analyzed separately as well as combined using parsimony and Bayesian approaches. Our results support the expanded tribe Spermacoceae as monophyletic. The former tribe Spermacoceae s. str. forms a monophyletic clade nested within the Hedyotis–Oldenlandia group. Several genera formerly recognized within the Hedyotis–Oldenlandia group are supported as monophyletic (Amphiasma Bremek., Arcytophyllum Willd. ex Schult. & Schult. f., Dentella J. R. Forst. & G. Forst., Kadua Cham. & Schltdl., and Phylohydrax Puff), while others appear to be paraphyletic (e.g., Agathisanthemum Klotzsch), biphyletic (Kohautia Cham. & Schltdl.), or polyphyletic (Hedyotis L. and Oldenlandia L. sensu Bremekamp). Morphological investigations of the taxa are ongoing in order to find support for the many new clades and relationships detected. This study provides a phylogenetic hypothesis with broad sampling across the major lineages of Spermacoceae that can be used to guide future species-level and generic studies.

In this study, foliar and petiole anatomy of several genera was compared to determine whether there are characteristics that can be used to reevaluate the circumscription and taxonomic position of Hamelieae (Rubiaceae). Our sample included a total of 36 species, which were sectioned using conventional embedding and staining methods. From these species, 23 represented six of the seven genera of Hamelieae sensu Robbrecht; Syringantha Standl. was included in order to reevaluate its putative inclusion within Hamelieae. For comparative purposes, the sample also included representative species of tribes Psychotrieae (Rubioideae), the Portlandia informal group (Cinchonoideae), and Gardenieae (Ixoroideae). Our results indicated that foliar and petiole anatomy contained taxonomic information that can be used in systematic studies. Members of Hamelieae shared the following characters: cuticle more than 3 µm, dorsiventral mesophyll, a single palisade parenchyma cell layer, loose spongy parenchyma, raphides,...

Putative synapomorphy assessment (primary homology assessment) is distinct for DNA strings having a codon structure (hereafter, coding DNA) versus those lacking it (hereafter, non-coding DNA). The first requires the identification of a reading frame and of usually few in-frame insertions and deletions. In non-coding DNA, where length variation is much more common, putative synapomorphy assessment is considerably less straightforward and highly depends on the alignment method. Appreciating the existence of evolutionary constraints, alignments that consider patterns associated with specific putative evolutionary events are favored. Once the sequences have been aligned, the postulated putative evolutionary events need to be coded as an additional step. In order for the alignments and the alignment coding to be falsifiable, they should be carried out using justified and explicitly formulated criteria. Alternative coding methods for the most common patterns present in alignments of non-coding DNA are discussed here. Simpler putative synapomorphy assessment will not always correlate to more reliable phylogenetic information because simplicity does not necessarily correlate to the degree of homoplasy. The use of non-coding DNA can result in more laborious coding, but at the same time in more corroborated hypotheses, mirroring their accuracy for phylogenetic inference.

A parsimony cladistic analysis based on 55 morphological characters was performed for the Cascabela Raf.–Thevetia L. species complex (Apocynaceae), including 22 terminals, sampling at least one species of each genus in Plumerieae sensu Endress and Bruyns. The consensus of the 12 most parsimonious trees (length = 164, consistency index = 0.50, retention index = 0.75) can be correlated to three previous subtribal classifications. The topology supports the monophyly of the Cascabela–Thevetia species complex, but it is not conclusive to whether Cascabela should be recognized as a genus or as a subgenus of Thevetia. Because there are two important and easy-to-diagnose characters supporting each clade (digitiform suprastaminal appendages and embryos not compressed in Cascabela; reniform fruits and segmented endocarp in Thevetia), the recognition of two genera is preferred here. Therefore, the new combination C. pinifolia (Standl. & Steyerm.) Alvarado-Cardenas & Ochot.-Booth is proposed. Keys and synopt...

Psychotria chamelaensis C. M. Taylor & E. Dominguez-Licona was previously confused with P. erythrocarpa Schlechtendal, but this new species can be recognized by its longer narrow calyx lobes and moderate to dense, usually appressed pubescence. It is well documented by specimens from the Chamela Biological Station in Jalisco, Mexico, and is so far known only from at or near that site.

Cerdia is a poorly understood genus of minute cushiony plants endemic to Mexico that is traditionally placed in subfamily Paronychioideae, tribe Polycarpeae (Caryophyllaceae). Morphological observations and phylogenetic analysis of ITS DNA sequences were carried out to determine the number of species, heretofore controversial, that constitute the genus as well as its position within Caryophyllaceae. Samples of Cerdia were collected through its entire range of distribution and together with previous specimens were used in morphological analyses. Nineteen terminal taxa were considered in a phylogenetic analysis with representatives of the different lineages in Caryophyllaceae. Results indicated that Cerdia is a monotypic genus, including only one variable species, C. virescens, but its phylogenetic affinities remain doubtful. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 152, 1–13.

The Caryophyllales constitute a major lineage of flowering plants with approximately 12?500 species in 39 families. A taxonomic backbone at the genus level is provided that reflects the current state of knowledge and accepts 749 genera for the order. A detailed review of the literature of the past two decades shows that enormous progress has been made in understanding overall phylogenetic relationships in Caryophyllales. The process of re-circumscribing families in order to be monophyletic appears to be largely complete and has led to the recognition of eight new families (Anacampserotaceae, Kewaceae, Limeaceae, Lophiocarpaceae, Macarthuriaceae, Microteaceae, Montiaceae and Talinaceae), while the phylogenetic evaluation of generic concepts is still well underway. As a result of this, the number of genera has increased by more than ten percent in comparison to the last complete treatments in the “Families and genera of vascular plants” series. A checklist with all currently accepted genus names in Caryophyllales, as well as nomenclatural references, type names and synonymy is presented. Notes indicate how extensively the respective genera have been studied in a phylogenetic context. The most diverse families at the generic level are Cactaceae and Aizoaceae, but 28 families comprise only one to six genera. This synopsis represents a first step towards the aim of creating a global synthesis of the species diversity in the angiosperm order Caryophyllales integrating the work of numerous specialists around the world. © 2015 BGBM Berlin.

This work evaluates the phylogenetic relationships between Stephaniellaceae, Arnelliaceae, Southbyaceae, and Gymnomitriaceae, and between genera and species of the Stephaniellaceae. We analysed morphological data obtained from herbarium specimens and from the literature under the parsimony criterion using equal weightings and implied weightings. The inclusion of Stephaniella and Stephaniellidium within Arnelliaceae, Southbyaceae or Gymnomitriaceae is not supported in this analysis. The clade Stephaniellaceae had a moderately high Jackknife support and the family was characterized by the following synapomorphies: presence of paraphyllia and presence of longitudinal folds in female bracts. Within the Stephaniellaceae, Stephaniella is corroborated as monophyletic and Stephaniellidium is resolved as its sister group. The relationship between Stephaniella uncifolia Winkler and Stephaniella hamata Stephani was strongly supported in both analyses while the relationship between Stephaniella paraphyllina Jack and Stephaniella boliviensis Stephani was weakly supported. With these results, S. boliviensis is proposed as a synonym of S. paraphyllina. We propose changes in the taxonomic position of Stephaniella and Stephaniellidium and in their classification in consideration of the complex morphology of the species and the lack of sexual structures and collections.

The Caribbean islands are a well-known biodiversity hotspot of global importance. Hispaniola (Dominican Republic and Haiti) is a highly diverse island with 42% of its species endemic. Here we describe the new monotypic genus Tainus (Rubiaceae, Rondeletieae), which is endemic to the Sierra de Bahoruco-La Selle. This taxon was originally published as Rondeletia pitreana, but its taxonomic status has been doubtful. We performed phylogenetic analyses with three chloroplast regions (petD, trnK-matK and trnL-F) in order to test the relationships of R. pitreana to other species of Rondeletia and allied genera. Our molecular phylogeny underscores that R. pitreana does not belong to Rondeletia, but has an isolated position within Rondeletieae, whereas Acrosynanthus is sister to an assemblage of Mazaea, Phyllomelia, Rachicallis, Roigella and Rondeletia. The recognition of the genus Tainus is supported by molecular (simple sequence repeats) and morphological characters, among which the most conspicuous is the densely papillate ornamentation of the corolla mouth and lobes. Our findings reveal another case of endemism at a deeper phylogenetic level in flowering plants on Hispaniola. Furthermore, they emphasize the importance of exploring, collecting and performing phylogenetic analyses integrating samples from larger geographical areas across countries as a basis to support nature conservation.

Helopini is a diverse tribe in the subfamily Tenebrioninae with a worldwide distribution. The New World helopine species have not been reviewed recently and several doubts emerge regarding their generic assignment as well as the naturalness of the tribe and subordinate taxa. To assess these questions, a preliminary cladistic analysis was conducted with emphasis on sampling the genera distributed in the New World, but including representatives from other regions. The parsimony analysis includes 30 ingroup species from America, Europe and Asia of the subtribes Helopina and Cylindrinotina, plus three outgroups, and 67 morphological characters. Construction of the matrix resulted in the discovery of morphological character states not previously reported for the tribe, particularly from the genitalia of New World species. A consensus of the 12 most parsimonious trees supports the monophyly of the tribe based on a unique combination of characters, including one synapomorphy. None of the subtribes or the genera of the New World represented by more than one species (Helops Fabricius, Nautes Pascoe and Tarpela Bates) were recovered as monophyletic. Helopina was recovered as paraphyletic in relation to Cylindrinotina. One Nearctic species of Helops and one Palearctic species of Tarpela (subtribe Helopina) were more closely related to species of Cylindrinotina. A relatively derived clade, mainly composed by Neotropical species, was found; it includes seven species of Tarpela, seven species of Nautes, and three species of Helops, two Nearctic and one Neotropical. Our results reveal the need to deeply re-evaluate the current classification of the tribe and subordinated taxa, but a broader taxon sampling and further character exploration is needed in order to fully recognize monophyletic groups at different taxonomic levels (from subtribes to genera).

In the analysis of sequence-based data matrices, the use of different methods of treating gaps has been demonstrated to in? fluence the resulting phylogenetic hypothe? ses (e.g., Eernisse and Kluge, 1993; Vogler and DeSalle, 1994; Simons and Mayden, 1997). Despite this influence, a well-justi? fied, uniformly applied method of treating gaps is lacking in sequence-based phyloge? netic studies. Treatment of gaps varies widely from secondarily mapping gaps onto the tree inferred from base characters

Trees or tree-like plants are defined here broadly as perennial, self-supporting plants with a total height of at least 5m (without ascending leaves or inflorescences), and with one or several erect stems with a diameter of at least 10cm. We continue our compilation of an updated list of all native Mexican tree species with the dicotyledonous families Asteraceae (36 species, 39% endemic), Leguminosae with its 3 subfamilies (449 species, 41% endemic), and Rubiaceae (134 species, 24% endemic). The tallest tree species reach 20m in the Asteraceae, 70m in the Leguminosae, and also 70m in the Rubiaceae. The species-richest genus is Lonchocarpus with 67 tree species in Mexico. Three legume genera are endemic to Mexico (Conzattia, Hesperothamnus, and Heteroflorum). The appendix lists all species, including their original publication, references of taxonomic revisions, existence of subspecies or varieties, maximum height in Mexico, and endemism status.

† Background and Aims Within Chenopodioideae, Atripliceae have been distinguished by two bracteoles enveloping the female flowers/fruits, whereas in other tribes flowers are described as ebracteolate with persistent perianth. Molecular phylogenetic hypotheses suggest ‘bracteoles’ to be homoplastic. The origin of the bracteoles was explained by successive inflorescence reductions. Flower reduction was used to explain sex determination. Therefore, floral ontogeny was studied to evaluate the nature of the bracteoles and sex determination in Atripliceae. † Methods Inflorescences of species of Atriplex, Chenopodium, Dysphania and Spinacia oleracea were investigated using light microscopy and scanning electron microscopy. † Key Results The main axis of the inflorescence is indeterminate with elementary dichasia as lateral units. Flowers develop centripetally, with first the formation of a perianth primordium either from a ring primordium or from five individual tepal primordia fusing post-genitally. Subsequently, five stamen primordia originate, followed by the formation of an annular ovary primordium surrounding a central single ovule. Flowers are either initially hermaphroditic remaining bisexual and/or becoming functionally unisexual at later stages, or initially unisexual. In the studied species of Atriplex, female flowers are strictly female, except in A. hortensis .I n Spinacia, female and male flowers are unisexual at all developmental stages. Female flowers of Atriplex and Spinacia are protected by two accrescent fused tepal lobes, whereas the other perianth members are absent. † Conclusions In Atriplex and Spinacia modified structures around female flowers are not bracteoles, but two opposite accrescent tepal lobes, parts of a perianth persistent on the fruit. Flowers can achieve sexuality through many different combinations; they are initially hermaphroditic, subsequently developing into bisexual or functionally unisexual flowers, with the exception of Spinacia and strictly female flowers in Atriplex, which are unisexual from the earliest developmental stages. There may be a relationship between the formation of an annular perianth primordium and flexibility in floral sex determination.

In the 1990s Rubiaceae became a hot spot for systematists, mainly due to the comprehensive treatment of the family by Robbrecht in 1988. Next to the exploration of macromolecular characters to infer the phylogeny, the palynology of Rubiaceae finally received the attention it deserves. This article aims to present a state-of-the-art analysis of the systematic palynology of the family. The range of variation in pollen morphology is wide, and some of the pollen features are not known from other angiosperm taxa; e.g., a looplike or spiral pattern for the position of apertures in pantoaperturate grains. We compiled an online database at the generic level for the major pollen characters and orbicule presence in Rubiaceae. An overview of the variation is presented here and illustrated per character: dispersal unit, pollen size and shape, aperture number, position and type, sexine ornamentation, nexine pattern, and stratification of the sporoderm. The presence/absence and morphological variation of orbicules at the generic level is provided as well. The systematic usefulness of pollen morphology in Rubiaceae is discussed at the (sub)family, tribal, generic, and infraspecific levels, using up-to-date evolutionary hypotheses for the different lineages in the family. The problems and opportunities of coding pollen characters for cladistic analyses are also treated. ispartof: Botanical review vol:71 issue:3 pages:354-414 status: published

One of the major goals of systematics is to provide a synthesis of knowledge on the diversity of a group of organisms, such as flowering plants. Biodiversity conservation and management call for rapid and accurate global assessments at the species level. At the same time the rapid development of evolutionary biology with a spectrum of approaches to test species relationships and species limits, has revolutionised and is still revolutionizing the science of plant systematics including taxonomy. We explore the relevant scientific and technological developments with the aim to suggest a conceptual framework for an integrated monographic synthesis which can reach global coverage. Our exemplar group are the Caryophyllales, which are a lineage of worldwide distribution, comprising approx. 5% of flowering plant species diversity. The current situation of classification is marked by a transition from pre-phylogenetic treatments to taxonomic treatments increasingly evaluated in an evolutionary context. Structured data (both molecular and morphological), linked to well-documented specimens will be important as fundamental entities of information that can be subjected to evolutionary analysis. As a result, taxon concepts are established as hypotheses which then can be used as basis for a classification system in a second step. Global syntheses need to provide information and use a classification system that reflects the current state of knowledge. In order to accommodate the constantly improved understanding of the organisms, eventually also resulting in the change of taxon concepts, the treatments need to be dynamic. The workflow for a global monographic synthesis as outlined here is supported by currently available biodiversity informatics tools such as the EDIT Platform for Cybertaxonomy. The availability of electronic sources (names, protologues, type images, literature) greatly facilitates the access to information, but as our case shows, considerable efforts for data curation and research are still needed. The implementation of a global monographic synthesis such as the Caryophyllales requires the involvement of the global scientific community. Fil: Borsch, Thomas. Freie Universität Berlin; Alemania. Berlin-Brandenburg Institute of Advanced Biodiversity Research; Alemania Fil: Hernández Ledesma, Patricia. Freie Universität Berlin; Alemania Fil: Berendsohn, Walter G.. Freie Universität Berlin; Alemania. Berlin-Brandenburg Institute of Advanced Biodiversity Research; Alemania Fil: Flores Olvera, Hilda. Universidad Nacional Autónoma de México. Departamento de Botánica; México Fil: Ochoterena, Helga. Universidad Nacional Autónoma de México. Departamento de Botánica; México Fil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: von Mering, Sabine. Freie Universität Berlin; Alemania. Botanischer Garten und Botanisches Museum Berlin-Dahlem; Alemania Fil: Kilian, Norbert. Freie Universität Berlin; Alemania. Botanischer Garten und Botanisches Museum Berlin-Dahlem; Alemania