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— The genus Spigelia (Loganiaceae) is a Neotropical genus that includes more than 80 species distributed from the United States to Argentina. Systematic studies of the group have rarely considered the carpological characters, so their taxonomic importance has not been analyzed in detail. The aim of this study is to analyze the morphological characteristics of these organs to provide more information for a better species separation and for a more robust infra-generic classification. We provide a detailed description of Spigelia fruits and seeds of the Mexican species since the country represents one of its main centers of diversification. Fruits and seed samples from 54 individuals across 14 species were measured and photographed to describe each one, maintaining as much detail as possible. With the morphological matrix a DFA, PCA, and a dendrogram using the NJ method was performed. The fruits and seeds of the Mexican Spigelia species proved to be taxonomically useful, allowing the differentiation of four main clusters of species separated by the size of the analyzed structures in the three analyses (DFA, PCA, NJ). The results show the variation in size and shape of the structures analyzed, which shows the taxonomic importance of fruits and seeds of the genus Spigelia. Our work represents an advance in the detailed knowledge of structures, which are rarely considered in the descriptions, and which allows us to have a separation of species. A taxonomic treatment and photographs of the fruits and seeds are also included.

The genus Cenophengus LeConte (1881) includes 27 species, distributed from southern United States to northern Costa Rica. In order to test the monophyly of Cenophengus, a cladistic analysis based on 81 morphological characters, 28 species of Cenophengus and 27 outgroup species was conducted. A clade supported by three synapomorphies corresponds to Cenophengus as a monophyletic group according to the relationships obtained under both equaland implied weights. The systematic relevance of the coding of the characters from the wing is discussed and the sequence of the character state transformations for the veins (radial twenty [r3], posterior radial twenty [RP] size, and anterior cubital veins [CuA]) is optimized in the cladogram obtained under implied weights. Cenophengus species are distributed in the Nearctic and Neotropical regions, and particularly in the Mexican Transition Zone, where their greatest diversity is found.

—Rogiera (Guettardeae, Rubiaceae) is a Neotropical genus distributed from Mexico to northern South America that includes shrubs, treelets, or trees, which were previously treated in the taxonomically controversial and confused Rondeletia complex. Rogiera can be recognized among other Rubiaceae by the combination of multiflowered inflorescences, heterostylous flowers, quincuncial corolla aestivation, a hairy ring at the corolla mouth, and capsular fruits with loculicidal dehiscence. Despite the recent taxonomic circumscription of Rogiera there is not a comprehensive taxonomic treatment to it. Moreover, regional floristic treatments disagree on the species circumscriptions, with discrepancies in the number of species of Rogiera from 11 to 20. Based on molecular and morphological evidence studied on field and herbarium specimens, we present a taxonomic revision of Rogiera. We recognize ten species; Mexico is the center of diversity with nine species, four of them endemic. An identification key, descriptions, distribution maps, nomenclatural history, phenological data, and illustrations of all the species in the genus are provided for the first time. Several names required lecto- or epitypifications designated here.

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.]

—The recent rediscovery of Jatropha riojae, which was considered as probably extinct, led to a taxonomic re-evaluation of the species due to its problematic circumscription with respect to morphologically similar species of Jatropha section Loureira subsect. Loureira. Based on our study, J. riojae is accepted, taxonomic clarifications are made, including the designation of a lectotype for the name, a complete description of vegetative and reproductive structures is provided, and the species is illustrated and compared to others with which it has been confused. The geographical distribution of J. riojae is clarified as endemic to the municipality of Acatlán, Puebla, Mexico in the south of the Balsas River Basin. To determine the conservation status of the species, the risk assessment method of the Mexican Red List (NOM 059-SEMARNAT-2010) was applied, indicating that J. riojae should be assigned to the “Endangered” category. A re-evaluation of the species under the IUCN criteria indicated that it should be assigned in the “Critically Endangered” (CR) category.

Seventeen morphologically related genera have been considered as the Rondeletia complex, traditionally in Rondeletieae. Molecular studies agree that this is a polyphyletic group and some genera have been transferred to Guettardeae. Nevertheless, no solid morphological characters support this hypothesis. Our aim is to explore pollen morphology to see if this source of characters has systematic value. Our study uses light and scanning electron microscopy for 30 species of both tribes representing 14 genera. The most important characters are polar outline, endoaperture type and nexine discontinuities. Our results do not permit diagnosis of tribes, but they show that the genera formerly included in the Rondeletia complex, but now placed in Guettardeae, have nexine discontinuities in polar areas: endofissures (Rogiera) or endocracks (Arachnothryx complex: Arachnothryx-Gonzalagunia-Javorkaea-Renistipula). Palynological data also confirm a close relationship of Rondeletia with Stevensia, corroborating their synonymy, and of Arachnothryx with Gonzalagunia-Javorkaea-Renistipula, providing evidence of their close relationship. We conclude that pollen is a useful source of characters for supporting main lineages, but further research is still necessary for other genera, including Blepharidium, Machaonia, Mazaea and additional Rondeletia spp.

—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.

This work represents the first phylogenetic analysis of all genera belonging to the plant family Theaceae (sensu lato). The study is based on 60 morphological characters derived from herbarium specimens and an extensive literature review of 37 genera (including the outgroup). In contrast to the results from molecular data, Theaceae is here found to consist of one clade in which the recognition of two families or subfamilies would leave Theaceae s.s. paraphyletic. Within that clade, Ternstroemiaceae is supported as monophyletic and includes Adinandra, Anneslea, Archboldiodendron, Balthasaria, Cleyera, Eurya, Euryodendron, Ficalhoa, Freziera, Symplococarpon, Ternstroemia and Visnea. The paraphyletic Theaceae s.s. includes Apterosperma, Camellia, Dankia, Gordonia, Pyrenaria, Schima, and Stewartia. Tetrameristaceae (Pentamerista and Tetramerista) are supported as a monophyletic family, with Pellicieraceae (Pelliciera) as sister group, and that clade is sister to the rest of the taxa. Bonnetiaceae (Archytaea and Bonnetia) and Kielmeyeroideae of the Clusiaceae (Caraipa, Haploclathra, Kielmeyera, Mahurea, Marila, and Neotatea) are also supported as monophyletic. Given the differences between the results obtained from morphological and molecular data, we consider that there is still a need for further research, including combined analyses.

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.

The circumscription of Rondeletieae has changed considerably over time. Historically, 85 genera have been included, characterized by small trees, imbricate corolla aestivation and capsules. Molecular studies led to a narrower circumscription and stressed out that Rondeletieae is mainly an Antillean clade. As historically circumscribed, Rondeletieae is both polyphyletic (involving several tribes, including Condamineae, Sipaneeae, etc.) and paraphyletic with respect to Guettardeae. Uncertainties persist on the tribal circumscription, and its generic limits and relationships. We report results of phylogenetic analyses under parsimony, maximum likelihood and Bayesian analyses including 179 taxa, using concatenated datasets of three chloroplast DNA regions (petD, trnL–F and trnK–matK), their DNA microstructural characters as well as morphology. Our objectives are to: test the monophyly of Rondeletieae and evaluate phylogenetic relationships, evaluate potential characters for tribal and generic delimitation and propose a circumscription for Rondeletieae according to phylogenetic hypothesis using morphological characters. The tribes Guettardeae and Rondeletieae are strongly supported as sister: quincuncial aestivation and spathulate corolla lobes are proposed as a unique combination of characters supporting this relationship. We did not find synapomorphies for each tribe, but there is a set of character combinations that allows distinguishing both tribes that includes the corolla and pollen ornamentation as well as fruit and seed morphology. After evaluating other genera not included in the phylogenies, our proposal is that Rondeletieae contains approximately 120 species in 20 neotropical genera: Acrosynanthus, Acunaeanthus, Blepharidium, Donnellyanthus, Mazaea, Phyllomelia, Rachicallis, Roigella, Rondeletia, Rovaeanthus, Suberanthus, Tainus, plus one tentatively included and recently described (Jamaicanthus).

Soils rich in gypsum (CaSO4·2H2O) are both a challenge for plant growth and a trigger for plant evolution. Plants that grow only on this type of soils are known as gypsophiles, but there are also generalists that grow on and off gypsum, known as gypsovags. The Cuatro Cienegas municipality (CCM) in Coahuila is characterized by a complex mosaic of soils with different gypsum contents, ranging from massive, ancient gypsum evaporite bedrock, crystalline selenite, and anhydrite to very recent formations of secondary evaporites, often mixed with other salts, and gypsum dunes. These exposures of gypsum (gypsum outcrops) host a species-rich gypsophilic flora that has mostly been described in only the last 50 years, and aside from the well-known gypsum deposits of Cuatro Cienegas Basin (CCB) is still imperfectly known. To date there is no available comprehensive synthesis for where the gypsum outcrops occur within CCM or for the vascular plant species growing on them. In this chapter we use remote sensing techniques to reveal botanically unexplored gypsum outcrops and we present a checklist for the vascular plant species currently known to occur on gypsum outcrops within CCM. We report 297 species in 187 genera and 60 families of vascular plants growing on gypsum outcrops in the CCM, of which 31 species are gypsophiles, five are halogypsophiles (species that grow on soils with a mixture of sodium chloride and gypsum), and three are either gypsophiles or halogypsophiles; 15 are endemic to the municipality. Our results demonstrate that the method presented here for detecting potential gypsum outcrops is powerful, that CCM has an outstanding number of potential gypsum outcrops, many of which are unexplored botanically. The relatively high number of gypsophiles in CCM and the fact that new taxa continue to be discovered clearly indicate the need for continued botanical exploration of gypsum environments in the Cuatro Cienegas region and in Coahuila and the Chihuahuan Desert as a whole.

Two new species of Arachnothryx (Guettardeae, Rubiaceae) from the cloud forest of the Sierra Norte of Oaxaca, Mexico are described and illustrated. Arachnothryx axillaris together with A. heteranthera are the only two species in the genus with axillary inflorescences, but otherwise they are not similar. The new species is more similar to A. capitellata, but it differs in pubescence and inflorescence morphology. Arachnothryx flores-olverae can be confused with A. buddleioides mainly because they share discolorous leaves with densely tomentose pubescence, but they differ in stipule and inflorescence morphology. With these two new species the Sierra Norte of Oaxaca becomes more evidently the main hotspot of species diversity for the genus.

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.

This is the first phylogenetic study focused on the Pavetteae, one of the most species-rich and morphologically diverse tribes within the coffee family (Rubiaceae). Fifteen of the 17 currently recognized genera, represented by 85 taxa, were sequenced for rps16, trnT-F and ITS and analysed using Bayesian inference and maximum likelihood methods. The monophyly of the Pavetteae is confirmed. Four major lineages are identified, but their phylogenetic relationships are not fully resolved. The continental African genera Rutidea, Nichallea and Tennantia, the Madagascan genera Homollea and Robbrechtia, and the paleotropical genus Pavetta are monophyletic. Other genera are paraphyletic in their current circumscriptions and the following changes are made: Homolliella is placed in synonymy with Paracephaelis, and Coleactina and Dictyandra with Leptactina, resulting in four new combinations. The large paleotropical genus Tarenna is shown not to be monophyletic. In the future, the name Tarenna should not be used for continental African species. Most of these could be transferred to the hitherto monospe- cific genus Cladoceras, but other species might constitute altogether new genera. The relationship between the monophyletic Asian-Pacific and Madagascan Tarenna species remains unclear. The phylogeny of the Madagascan genera of the Pavetteae is largely unresolved and the largest Madagascar-centred genus Coptosperma was not recovered as monophyletic. The low resolution for the Madagascan taxa can be considered as an indication of rapid radiation. Further molecular and morphologi- cal studies are necessary to clarify the phylogeny of the Pavetteae, especially regarding the African Tarenna species and the Madagascan genera of the tribe.

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.

Senna acatlanensis is described and illustrated here. This species is restricted to a forest ecotone in southern Puebla (Mexico), and stands out by its unique large asymmetric flowers, with yellow petals that do not fade away to reddish-brown as they dry-out, heteromorphic and variable androecium; with four staminodes, ten or less fertile stamens; by its pendulous, cylindrical fruits, with chartaceous strigillose valves, and inter-seminal septa with a black-pulpy endocarp that surrounds exareolate seeds. These morphological attributes in addition to leaves with two pairs of leaflets, anthers with beaks, gynoecium multi-ovulated, and transversely oriented seed, turned broadside to the septa placed this new species within the series Bacillares. Illustrations, taxonomic comments, distribution and conservation status are provided with a key to the Mexican species of series Bacillares.

Rovaeanthus (Rondeletieae, Rubiaceae) is a Mesoamerican endemic genus of two species, characterized by a fleshy, pubescent ring at the corolla mouth. Despite the molecular evidence, which suggested that Rovaeanthus shares a most recent common ancestor with the rest of the tribe Rondeletieae, it was treated as a synonym of Rogiera (Guettardeae), with which it shares the pubescent ring at the corolla mouth. Although the species circumscription of Rovaeanthus is clear, its recognition as a separate genus is not yet widely accepted. An updated identification key for the two species of Rovaeanthus, descriptions, distribution maps, phenological data, conservation status, and illustrations are provided.

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.

We studied floral morphology and anatomy of seven genera of the tribe Hamelieae sensu Manns & Bremer with the goal to evaluate the potential of these characters in the circumscription of the tribe. Twenty two species of Hamelieae were studied as well as ten representative species of the Cinchonoideae, Ixoroideae, and Rubioideae subfamilies for comparative purposes. The Hamelieae members had stamens adnate to the corolla base, anther dorsifixed with introrse dehiscence, amphivasal vascular bundle in the filament, endothecium of one layer of cells, papillose stigma, axile placentation, orthotropous and unitegmic ovules, epidermal cells of the integument with tannins, and idioblasts with raphides in all whorls. Exostema and Hintonia (Cinchonoideae) share with Hamelieae the stamens adnate to the corolla base and the imbricate aestivation. However, these genera are unlike of the tribe because they have anthers with latrorse dehiscence, round filaments, ovoid styles with a constriction, anatropous ovules with basipetal orientation, and idioblasts with druses or crystal sands. Rubioideae and Cinchonoideae representatives unlike Hamelieae and species of Cinchonoideae studied have valvate and contorted to the left aestivation, anthers dorsifixed at the middle, stamens adnate to the throat of the corolla, and trichomes in the throat of the corolla tube. The imbricate aestivation, the occurrence of raphides, and the adnate stamens of the corolla base supported the relationships among Hamelieae and Cinchonoideae as suggested by molecular phylogenies.

This study aimed to test the phylogenetic relationships of the tribe Cacteae, the generic circumscription within the tribe, in particular, the monophyly of the genus Ferocactus, and to provide a biogeographical hypothesis about the origin of Cacteae. The analysis included 135 species from all of the 27 accepted genera and four outgroup species. Five chloroplast regions were sequenced, aligned, and coded postulating gaps, simple sequence repeats (SSRs), and inversions as potential synapomorphies, and their contributions to phylogenetic reconstruction were evaluated. The phylogenetic analyses recovered 63% of the genera as monophyletic. The contribution of rpl16, trnL-F and psbA to the phylogenetic signal was higher than in the two more slowly evolving genes (rbcL, matK), but the gaps and SSRs supported some of the genera. This result differs from those of previous phylogenetic studies in which less than 35% of the genera were recovered as monophyletic. In this work, Astrophytum and Echinocactus were re-cir...

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.

We studied wood and bark anatomy of six (Deppea, Hamelia, Hoffmannia, Omiltemia, Pinarophyllon, and Plocaniophyllon) of the seven genera of the tribe Hamelieae sensu Robbrecht, and Syringantha with as main purposes to determine if there are characters that support the boundaries of the Hamelieae, to evaluate the status of Syringantha as a member of the Hamelieae, and to evaluate the taxonomic position of Hamelieae within the subfamilies Rubioideae or Cinchonoideae. In addition, we studied for comparative purposes representative species of Psychotria (Psychotrieae, Rubioideae), Exostema, and Hintonia (Portlandia group, Cinchonoideae), Randia (Gardenieae, Ixoroideae), and Bouvardia (incertae sedis). Bark of most genera studied had a single periderm, while a rhytidome was observed in Exostema and few species of Psychotria. The mineral inclusions allowed recognizing related genera, for example, raphides in Hamelieae and Psychotria, prisms in Exostema, and druses in Randia. Members of Hamelieae showed wood type II, distinctive by the occurrence of libriform septate fibres, vessels in radial multiples of 2–6 vessels (80–90%, vessel grouping index 1.79–2.74), and diffuse apotracheal parenchyma. Syringantha shares with members of Hamelieae the presence of an endodermis, raphides in the bark, and wood type II. The combination of other wood characters mainly lend quantitative support to the taxonomic delimitation of some genera within Hamelieae. Raphides and wood type II supported a close relationship between Hamelieae and Hillieae within Cinchonoideae; characters that distinguish them from the other members of Cinchonoideae. Our results suggest independent origins of wood type II within the Rubiaceae. In addition, vessel density and diameter are discussed as possible adaptations to the different forest types where members of Hamelieae occur.

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.

The tribe Hamelieae sensu Robbrecht comprises seven genera, and is traditionally placed in subfamily Rubioideae. Molecular data, however, places Hamelieae within Cinchonoideae. In this study, leaf architecture characters were examined in order to provide further evidence for the circumscription of Hamelieae and discuss its placement in the proposed subfamilies. Leaves from 34 species belonging to six genera of the Hamelieae, plus Syringantha and representative species of Psychotrieae (Rubioideae), Cinchoneae (Cinchonoideeae) and Gardenieae (Ixoroideae) were studied in order to describe and compare their leaf architecture. The results showed that there are macromorphological characters shared by members of Hamelieae. The venation of Hamelieae is brochidodromous, as in the other sampled taxa, except Bouvardia, which has actinodromous venation and Randia with eucamptodromous-brochidodromous venation. In Hamelieae and Psycho- trieae, marginal ultimate venation forms a fimbrial vein and raphides are present in the mesophyll, while in representatives of Cinchoneae and Gardenieae, marginal ultimate venation is incomplete and raphides are absent. Syringantha is distinguished by its narrow elliptical to lanceolate lamina, but shares several attributes with Hamelia and Hoffmannia. These attributes support the proposal to include Syringantha in Hamelieae. The results neither resolve the placement of Hamelieae in Rubioideae or Cinchonoideae. However, our current phylogenetic understanding of the family, placing this tribe in a clade within Cinchonoideae, suggests that raphides arised more than once independently, thus raphides should not be a taxonomic marker to define the Rubioideae. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Die Blattarchitektur der Hamelieae (Rubiaceae). Die Tribus Hamelieae sensu Robbrecht umfasst sieben Gattungen und wird traditionsgemas in die Unterfamilie Rubioideae gestellt. Molekulardaten verweisen die Hamelieae zu den Cinchonoideae. In dieser Untersuchung werden Merkmale des Blattbaus uberpruft, um die Tribus Hamelieae zu umgrenzen und die beiden vorgeschlagenen Unterfamilien kritisch zu beleuchten. Es wurden die Blatter von 34 Arten, die zu sechs Gattungen der Hamelieae gehoren, plus Syringantha und representative Arten der Psychotrieae (Rubioideae), Cinchoneae (Cinchonoideae) und Gardenieae (Ixoroideae) untersucht, um den Bau ihrer Blatter zu beschreiben und zu vergleichen. Die Ergebnisse zeigten, welche makromorphologischen Merkmale von den Mitgliedern der Hamelieae geteilt werden. Die Nervatur der Hamelieae ist brochidodrom so wie in anderen Tribus, auser Bouvardia, die eine actinodrome Nervatur hat, und Randia mit eucamptodromer Nervatur. Bei den Hamelieae und Psychotrieae bildet die letzte Randnervatur eine fimbriale Ader und Raphiden sind im Mesophyll vorhanden, wahrend bei den Vertretern der Cinchoneae und Gardenieae die letzte Randnervatur unvollstandig ist und die Raphiden fehlen. Syringantha zeichnet sich durch ihre schmale elliptische bis lanzettliche Blattspreite aus, teilt aber einige Merkmale mit Hamelia und Hoffmannia. Auf diese Merkmale stutzt sich der Vorschlag, Syringantha in die Hamelieae einzuschliesen. Die Anwesenheit von Raphiden und das Muster der letzten Randnervatur unterstutzen die traditionelle Einordnung der Hamelieae in die Rubioideae. Phylogenetische Beweise jedoch, die diese Tribus in einen Clade mit den Vertretern der Cinchonoideae stellen, geben zu erkennen, dass die Raphiden mehr als einmal unabhangig von einander entstanden sind.

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.

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.