Lúcia G. Lohmann

New Brazilian Floristic List Highlights Conservation Challenges

A comprehensive new inventory of Brazilian plants and fungi was published just in time to meet a 2010 Convention on Biological Diversity target and offers important insights into this biodiversitys global significance. Brazil is the home to the worlds richest flora (40,989 species; 18,932 endemic) and includes two of the hottest hotspots: Mata Atlântica (19,355 species) and Cerrado (12,669 species). Although the total number of known species is one-third lower than previous estimates, the absolute number of endemic vascular plant species is higher than was previously estimated, and the proportion of endemism (56%) is the highest in the Neotropics. This compilation serves not merely to quantify the scale of the challenge faced in conserving Brazils unique flora but also serves as a key resource to direct action and monitor progress. Similar efforts by other megadiverse countries are urgently required if the 2020 targets of the Convention on Biological Diversity and the Global Strategy for Plant Conservation are to be attained.

Untangling the phylogeny of neotropical lianas (Bignonieae, Bignoniaceae)

The tribe Bignonieae (Bignoniaceae) is a large and morphologically diverse clade of neotropical lianas. Despite being a conspicuous component of the neotropical flora, the systematics of the tribe has remained uncertain due to confusing patterns of morphological variation within the group. Chloroplast (ndhF) and nuclear (PepC) DNA sequences were used here to reconstruct the phylogeny of Bignonieae. Individual analyses of ndhF and PepC were highly similar to one another, yet localized differences in the placement of six species suggests some conflict between data sets. Combined analyses result in trees that are consistent with those from the individual analyses and provide greater support for the suggested relationships. This phylogeny provides important new insights into the systematics of the tribe. It identifies 21 strongly supported species groups, eight of which broadly correspond to currently recognized genera. In addition, each of these 21 species groups is supported by morphological synapomorphies. The consistency between morphological and molecular data suggests that the current phylogeny provides a solid framework for a formal revision of the generic-level classification and for addressing other aspects of the biology of Bignonieae.

Evolutionary biology in biodiversity science, conservation, and policy: A call to action

Evolutionary biologists have long endeavored to document how many species exist on Earth, to understand the processes by which biodiversity waxes and wanes, to document and interpret spatial patterns of biodiversity, and to infer evolutionary relationships. Despite the great potential of this knowledge to improve biodiversity science, conservation, and policy, evolutionary biologists have generally devoted limited attention to these broader implications. Likewise, many workers in biodiversity science have underappreciated the fundamental relevance of evolutionary biology. The aim of this article is to summarize and illustrate some ways in which evolutionary biology is directly relevant. We do so in the context of four broad areas: (1) discovering and documenting biodiversity, (2) understanding the causes of diversification, (3) evaluating evolutionary responses to human disturbances, and (4) implications for ecological communities, ecosystems, and humans. We also introduce bioGENESIS, a new project within DIVERSITAS launched to explore the potential practical contributions of evolutionary biology. In addition to fostering the integration of evolutionary thinking into biodiversity science, bioGENESIS provides practical recommendations to policy makers for incorporating evolutionary perspectives into biodiversity agendas and conservation. We solicit your involvement in developing innovative ways of using evolutionary biology to better comprehend and stem the loss of biodiversity.

A New Generic Classification of Tribe Bignonieae (Bignoniaceae)1

Abstract The history of classification of the tribe Bignonieae and its genera are reviewed as context for a comprehensive new genus-level classification of the tribe Bignonieae (Bignoniaceae, Lamiales). This new classification is based on a well-supported phylogeny based on multiple molecular markers from both chloroplast and nuclear DNA, a morphological survey, and a broad sampling of taxa. Genera are circumscribed here as clades that are well supported as monophyletic by molecular data and also recognizable by one or more morphological synapomorphies. Perianthomega Bureau ex Baill. is here transferred from Bignoniaceae tribe Tecomeae into Bignonieae, and 21 genera and a total of 393 species are recognized in Bignonieae: Adenocalymma Mart. ex Meisn. (82 species), Amphilophium Kunth (47), Anemopaegma Mart. ex Meisn. (45), Bignonia L. (28), Callichlamys Miq. (1), Cuspidaria DC. (19), Dolichandra Cham. (8), Fridericia Mart. (67), Lundia DC. (13), Manaosella J. C. Gomes (1), Mansoa DC. (12), Martinella Baill. (2), Neojobertia Baill. (2), Pachyptera DC. ex Meisn. (4), Perianthomega (1), Pleonotoma Miers (17), Pyrostegia C. Presl (2), Stizophyllum Miers (3), Tanaecium Sw. (17), Tynanthus Miers (15), and Xylophragma Sprague (7). Several genera are here circumscribed differently from previous classifications, in particular Memora Miers and Sampaiella J. C. Gomes are synonymized with Adenocalymma; Distictella Kuntze, Distictis Mart. ex Meisn., Glaziova Bureau, Pithecoctenium Mart. ex DC., and Urbanolophium Melch. are synonymized with Amphilophium; Cydista Miers, Clytostoma Miers ex Bureau, Macranthisiphon Bureau ex K. Schum., Mussatia Bureau ex Baill., Phryganocydia Mart. ex Bureau, Potamoganos Sandwith, Roentgenia Urb., and Saritaea Dugand are synonymized with Bignonia; Macfadyena A. DC., Melloa Bureau, and Parabignonia Bureau ex K. Schum. are synonymized with Dolichandra; Arrabidaea DC. is synonymized with Fridericia; Gardnerodoxa Sandwith is synonymized with Neojobertia; Leucocalantha Barb. Rodr. is synonymized with Pachyptera; and Ceratophytum Pittier, Periarrabidaea A. Samp., Paragonia Bureau, Pseudocatalpa A. H. Gentry, and Spathicalyx J. C. Gomes are synonymized with Tanaecium. The genera Adenocalymma, Amphilophium, Fridericia, Dolichandra, and Tanaecium are formally emended here as to diagnosis and circumscription. A natural key, complete morphological descriptions, and illustrations characterize the accepted genera, and full generic synonymy and a catalogue of their component species summarize their basic nomenclature and geographic range. Three new names are published: B. neouliginosa L. G. Lohmann replaces Phryganocydia uliginosa Dugand; B. neoheterophylla L. G. Lohmann replaces Cydista heterophylla Seibert; and Tanaecium neobrasiliense L. G. Lohmann replaces Sanhilaria brasiliensis Baill. Thirty-two generic names are newly synonymized, and 144 new nomenclatural combinations are made. A lectotype is designated for one genus, Periarrabidaea A. Samp., and 78 species names. One species name is neotypified, Memora campicola Pilg. (≡ Adenocalymma campicola (Pilg.) L. G. Lohmann).

Phylogenetic position and floral function of Siparuna (Siparunaceae: Laurales)

Nucleotide sequences for two chloroplast genome regions, the rbcL gene and the trnL-trnF spacer region, were obtained for 22 genera and 30 species representing all major lineages of Laurales, with a special sampling effort being made in the phylogenetically problematic Monimiaceae sensu lato. Magnoliaceae, Winteraceae, Austrobaileyaceae, and Saururaceae were used as outgroups. A morphological character matrix for the same taxa was compiled and includes new floral-anatomical data for Siparunaceae, a lineage traditionally placed in Monimiaceae. Phylogenetic analyses of the molecular and morphological data based on maximum parsimony reveal that Siparuna and its sister taxon, the monotypic West African genus Glossocalyx, are not closely related to the remaining Monimiaceae, supporting the view that the Monimiaceae in the wide sense are polyphyletic. Based on morphology and chromosome numbers, Siparuna forms a clade with Atherospermataceae and Gomortegaceae, while based on rcbL sequences, it is in a clade with Hernandiaceae, Atherospermataceae, and Gomortegaceae. The trnL-trnF sequences provide no resolution for basal nodes in Laurales but agree with the rbcL and morphological analyses in strongly supporting a placement of Siparunaceae away from Monimiaceae s.str. Based on the phylogenetic hypotheses, we analyze some of the reported floral-morphological trends noted in Monimiaceae and Laurales, such as miniaturization of ovules, increasingly complete enclosure of reproductive organs, and aquisition of functional syncarpy. Both Siparuna and Glossocalyx have polycarpellate gynoecia embedded in massive receptacles covered by a membrane and uniovulate carpels with unitegmic ovules. The membrane, or floral roof, has a small, central pore for the styles or anthers to emerge at anthesis. It is more developed and thicker in female flowers than in male ones. Consequently, the styles in particular are forced into close physical contact. Flowers are pollinated by gall midges that oviposit into them through the pore in the floral roof, whereby they contact stamens or styles. Anatomical studies of flowers representing eight species show that styles fuse postgenitally at the height where they emerge through the pore, resulting in a joint transmission track for pollen tubes that originally landed on different stigmas. Lateral growth of pollen tubes, which results in switching between carpels, was observed in an experimentally pollinated species that had received large pollen loads.

The rise and evolution of the cambial variant in Bignonieae (Bignoniaceae)

SUMMARY Cambial variants represent a form of secondary growth that creates great stem anatomical diversity in lianas. Despite the importance of cambial variants, nothing is known about the developmental mechanisms that may have led to the current diversity seen in these stems. Here, a thorough anatomical analysis of all genera along the phylogeny of Bignonieae (Bignoniaceae) was carried out in order to detect when in their ontogeny and phylogeny there were shifts leading to different stem anatomical patterns. We found that all species depart from a common developmental basis, with a continuous, regularly growing cambium. Initial development is then followed by the modification of four equidistant portions of the cambium that reduce the production of xylem and increase the production of phloem, the former with much larger sieve tubes and an extended lifespan. In most species, the formerly continuous cambium becomes disjunct, with cambial portions within phloem wedges and cambial portions between them. Other anatomical modifications such as the formation of multiples of four phloem wedges, multiple‐dissected phloem wedges, and included phloem wedges take place thereafter. The fact that each novel trait raised on the ontogenetic trajectory appeared in subsequently more recent ancestors on the phylogeny suggests a recapitulatory history. This recapitulation is, however, caused by the terminal addition of evolutionary novelties rather than a truly heterochronic process. Truly heterochronic processes were only found in shrubby species, which resemble juveniles of their ancestors, as a result of a decelerated phloem formation by the variant cambia. In addition, the modular evolution of phloem and xylem in Bignonieae seems to indicate that stem anatomical modifications in this group occurred at the level of cambial initials.

An overview of the anatomy, development and evolution of the vascular system of lianas

Background: Lianas present many interesting structural features that are linked to their climbing habit. Having lost substantial amounts of supporting tissue, these plants depend on external structures for support. Meanwhile, during their evolutionary history, they have gained additional conductive and storage tissues. The wood of lianas generally includes wider vessels, larger amounts of axial parenchyma, larger rays, and longer fibres than those of trees. Cambial variants represent another key anatomical feature of lianas. Aims: In this paper, we review various aspects of liana biology, including those associated with their vascular system and water conduction, secondary growth and seasonal responses to environmental variability, as well as aspects related to the evolution of their cambial variants. Methods: Examples from the Bignoniaceae and Leguminosae, the two most abundant liana taxa in the Neotropics, are presented in a series of case studies, bringing new data, such as the activity of the cambium during the dry seasons; the radial conducting elements that are associated with the habit; the cambial variant of Bignonieae that has evolved in a recapitulatory fashion; and the increased specialisation for photosynthate conduction by the phloem. Conclusions: Altogether, lianas represent an excellent model for studies on the convergent evolution of plants.

Checklist das Spermatophyta do Estado de São Paulo, Brasil

The Phanerogamic Flora of Sao Paulo State project has been dedicated to create an inventory of the flora for 20 years. More than 200 collaborators are involved, mostly from the State of Sao Paulo, with the contributions of researchers from other states and from abroad. Since 2001, seven books with monographs of 151 families were published, dealing with 3,237 species within 722 genera. This project was the starting-point of the gathering of information about the diversity of spermatophytes of the State of Sao Paulo. The current checklist, at this point, presents an updated and virtually complete list of species, all certified by specialists. It also contains references to scientific collections for most of the taxa (vouchers) or to bibliography referring to the natural or subspontaneous occurrence of the species in the State. The list now contains 7,305 species distributed in 1,776 genera and in 197 spermatophyte families (according to Cronquist 1981) or 195 (according to APG III). 23% of the 31,728 species of spermatophytes listed in the Flora of Brazil occur in Sao Paulo State. The most representative families are Orchidaceae (797 species), Asteraceae (676 species), Fabaceae (513 species), Poaceae (500 species), Myrtaceae (304), Rubiaceae (265 species) and Melastomataceae (253 species), which, altogether, accumulate 3,308 species and constitute 45% of total species of spermatophytes in the state. The wealth of the Brazilian plant diversity, partially expressed in Sao Paulo, shows how important is the continuity of floristic studies in a country that is very likely to hold the largest plant diversity in the planet.

Do extrafloral nectaries present a defensive role against herbivores in two species of the family Bignoniaceae in a Neotropical savannas

Despite the general belief that the interaction between extrafloral nectaries (EFNs) and ants is mutualistic, the defensive function of EFNs has been poorly documented in South American savannas. In this article, we evaluate the potential impact of EFNs (benefits and costs) on two species of plants from the dry areas of Central Brazil, Anemopaegma album and Anemopaegma scabriusculum (Bignoniaceae). In particular, we characterize the composition of substances secreted by the EFNs, test whether EFNs attract ants, and whether ants actually present a defensive role, leading to reduced herbivory and increased plant fitness. Histochemical analyses indicated that EFNs from both species of Anemopaegma secrete an exudate that is composed of sugars, and potentially lipids and proteins. Furthermore, EFNs from both species were shown to present a significant role in ant attraction. However, contrary to common expectations, ants were not found to protect plants against herbivore attack. No effect was found between ant visitation and flower or fruit production in A. album, while the presence of ants led to a significant decrease in flower production in A. scabriusculum. These results suggest that EFNs might present a similar cost and benefit in A. album, and a higher cost than benefit in A. scabriusculum. Since the ancestor of Anemopaegma occupied humid forests and already presented EFNs that were maintained in subsequent lineages that occupied savannas, we suggest that phylogenetic inertia might explain the presence of EFNs in the species of Anemopaegma in which EFNs lack a defensive function.

Complete Chloroplast Genome of Tanaecium tetragonolobum: The First Bignoniaceae Plastome

Bignoniaceae is a Pantropical plant family that is especially abundant in the Neotropics. Members of the Bignoniaceae are diverse in many ecosystems and represent key components of the Tropical flora. Despite the ecological importance of the Bignoniaceae and all the efforts to reconstruct the phylogeny of this group, whole chloroplast genome information has not yet been reported for any members of the family. Here, we report the complete chloroplast genome sequence of Tanaecium tetragonolobum (Jacq.) L.G. Lohmann, which was reconstructed using de novo and referenced-based assembly of single-end reads generated by shotgun sequencing of total genomic DNA in an Illumina platform. The gene order and organization of the chloroplast genome of T. tetragonolobum exhibits the general structure of flowering plants, and is similar to other Lamiales chloroplast genomes. The chloroplast genome of T. tetragonolobum is a circular molecule of 153,776 base pairs (bp) with a quadripartite structure containing two single copy regions, a large single copy region (LSC, 84,612 bp) and a small single copy region (SSC, 17,586 bp) separated by inverted repeat regions (IRs, 25,789 bp). In addition, the chloroplast genome of T. tetragonolobum has 38.3% GC content and includes 121 genes, of which 86 are protein-coding, 31 are transfer RNA, and four are ribosomal RNA. The chloroplast genome of T. tetragonolobum presents a total of 47 tandem repeats and 347 simple sequence repeats (SSRs) with mononucleotides being the most common and di-, tri-, tetra-, and hexanucleotides occurring with less frequency. The results obtained here were compared to other chloroplast genomes of Lamiales available to date, providing new insight into the evolution of chloroplast genomes within Lamiales. Overall, the evolutionary rates of genes in Lamiales are lineage-, locus-, and region-specific, indicating that the evolutionary pattern of nucleotide substitution in chloroplast genomes of flowering plants is complex. The discovery of tandem repeats within T. tetragonolobum and the presence of divergent regions between chloroplast genomes of Lamiales provides the basis for the development of markers at various taxonomic levels. The newly developed markers have the potential to greatly improve the resolution of molecular phylogenies.