Bayesian tip-dated phylogeny and biogeography of Cissampelideae (Menispermaceae): Mitigating the effects of homoplastic morphological characters.

The integration of morphological and molecular data is essential to understand the affinities of fossil taxa and spatio-temporal evolutionary processes of organisms. However, homoplastic morphological characters can mislead the placement of fossil taxa and impact downstream analyses. Here, we provide an example of how to mitigate effectively the effect of morphological homoplasy on the placement of fossil taxa and biogeographic inferences of Cissampelideae. We assembled three data types, morphological data only, morphological data with a molecular scaffold and combined morphological and molecular data. By removing high-level homoplastic morphological data or reweighting the morphological characters, we conducted 15 parsimony, 12 undated Bayesian and four dated Bayesian analyses. Our results show that the 14 selected Cissampelideae fossil taxa are placed poorly when based only on morphological data, but the addition of molecular scaffold and combination of morphological and molecular data greatly improve the resolution of fossil nodes. We raise the monotypic Stephania subg. Botryodiscia to generic status and discover that three fossils previously assigned to Stephania should be members of Diploclisia. The Bayesian tip-dated tree recovered by removing homoplastic morphological characters with a Rescaled Consistency Index <0.25 has the highest stratigraphic fit and consequently generates more reasonable biogeographic reconstruction for Cissampelideae. Cissampelideae began to diversify in Asia in the latest Cretaceous and subsequently dispersed to South America around the Cretaceous-Palaeogene boundary. Two dispersal events from Asia to Africa occurred in the Early Eocene and the Late Eocene-Late Oligocene, respectively. These findings provide guidelines and practical methods for mitigating the effects of homoplastic morphological characters on fossil placements and Bayesian tip-dating, as well as insights into the past tropical floristic exchanges among different continents.

Fossil moonseeds from the Paleogene of West Gondwana (Patagonia, Argentina).

PREMISE OF THE STUDY: The fossil record is critical for testing biogeographic hypotheses. Menispermaceae (moonseeds) are a widespread family with a rich fossil record and alternative hypotheses related to their origin and diversification. The family is well-represented in Cenozoic deposits of the northern hemisphere, but the record in the southern hemisphere is sparse. Filling in the southern record of moonseeds will improve our ability to evaluate alternative biogeographic hypotheses. METHODS: Fossils were collected from the Salamanca (early Paleocene, Danian) and the Huitrera (early Eocene, Ypresian) formations in Chubut Province, Argentina. We photographed them using light microscopy, epifluorescence, and scanning electron microscopy and compared the fossils with similar extant and fossil Menispermaceae using herbarium specimens and published literature. KEY RESULTS: We describe fossil leaves and endocarps attributed to Menispermaceae from Argentinean Patagonia. The leaves are identified to the family, and the endocarps are further identified to the tribe Cissampelideae. The Salamancan endocarp is assigned to the extant genus Stephania. These fossils significantly expand the known range of Menispermaceae in South America, and they include the oldest (ca. 64 Ma) unequivocal evidence of the family worldwide. CONCLUSIONS: Our findings highlight the importance of West Gondwana in the evolution of Menispermaceae during the Paleogene. Currently, the fossil record does not discern between a Laurasian or Gondwanan origin; however, it does demonstrate that Menispermaceae grew well outside the tropics by the early Paleocene. The endocarps' affinity with Cissampelideae suggests that diversification of the family was well underway by the earliest Paleocene.

Phytogeographic implications of fossil endocarps of Menispermaceae from the Paleocene of Colombia.

PREMISE OF THE STUDY: Fossil leaves of Menispermaceae were previously described from the Paleocene of Colombia. Because of strong homoplasy of leaf characters, the fossils could not be placed more specifically within recognized clades, and additional data were needed to specify intrafamilial and paleogeographic relationships during the Paleocene. METHODS: Fossil endocarps of Menispermaceae were collected from the Cerrejón Formation, the recently discovered Bogotá flora, and Wyoming (∼60 Ma). We surveyed the endocarp morphology of almost all extant genera, conducted character optimization, a molecular scaffold analysis, and critically reviewed the related fossil genera. KEY RESULTS: Parallel syndromes of fruit characters have appeared in unrelated clades of the family according to current phylogenetic reconstructions. However, mapping selected endocarp characters across those clades that contain horseshoe-shaped endocarps facilitates identification and phylogenetic assessment of the fossils. Three fossil species are recognized. One of them belongs to the extant genus Stephania, which today grows only in Africa and Australasia. Palaeoluna gen. nov. is placed within the pantropical clade composed of extant Stephania, Cissampelos, and Cyclea; this morphogenus is also recognized from the Paleocene of Wyoming. Menispina gen. nov. shows similarity with several unrelated clades. CONCLUSIONS: The new fossils from Colombia reveal a complex paleobiogeographic history of the recognized clades within Menispermaceae, suggesting a more active exchange among neotropical, paleotropical, North American, and European paleoforests than previously recognized. In addition, the new fossils indicate that neotropical forests were an important biome for the radiation and dispersal of derived lineages in Menispermaceae after the Cretaceous-Paleogene boundary.

Polar compounds isolated from the leaves of Albertisia delagoensis (Menispermaceae).

Aqueous infusions of the leaves of the shrub Albertisia delagoensis (Menispermaceae) are used in South Africa in traditional Zulu medicine to alleviate a variety of symptoms, including fever, and intestinal problems. We report the analysis of such an aqueous extract using the HPLC-NMR technique. A number of polar compounds were identified, including proto-quercitol, nicotinic acid, allantoic acid, 3,4-dihydroxy-benzoic acid, phthalic acid and the aporphine alkaloid derivative roemrefidine. Allantoic acid and roemrefidine have been fully characterised by (1)H- and (13)C-NMR and mass spectrometry. Earlier reports of antiplasmodial activity of roemrefidine and of A. delagoensis extracts are correlated with this study and with the antipyretic properties of neutral aqueous extracts.

Estudo farmacobotânico de folhas de Cissampelos sympodialis Eichl. (Menispermaceae) / Pharmacobotanical study of the leaves of Cissampelos sympodialis Eichl., (Menispermaceae)

Cissampelos sympodialis Eichl. é uma espécie empregada na medicina popular do Nordeste do Brasil, cujos estudos farmacológicos são bastantes promissores no tratamento de doenças do trato respiratório. Neste trabalho realizou-se um estudo farmacobotânico de suas folhas, com o objetivo de elaborar morfodiagnoses macroscópicas e microscópicas que auxiliem sua caracterização. Realizaram-se secções paradérmicas (lâminas) e transversais de folhas (lâmina e pecíolo), posteriormente clarificadas e coradas com safranina e safrablue, respectivamente, e observadas ao microscópio óptico. Cissampelos sympodialis caracteriza-se pelas folhas peltadas, com as lâminas deltóides, nervação actinodroma-broquidodroma, e o pecíolo espessado nas extremidades. A epiderme é hipoestomática, com células de paredes anticlinais ondeadas na face adaxial e irregularmente sinuosa a ondeada na abaxial. O mesofilo é dorsiventral e o sistema vascular do pecíolo é formado de um anel de feixes isolados colaterais. Esparsos idioblastos de cristais prismáticos foram observados no parênquima peciolar. A morfologia foliar em conjunto com a anatomia da epiderme são caracteres distintivos para Cissampelos sympodialis.

Cissampelos sympodialis Eichl. is a plant species used in popular medicine in Northeast of Brazil, whose pharmacological studies are very promising in the treatment of diseases of the respiratory tract. In this work, a pharmacobotanical study of the leaves was performed with the objective to elaborate a macroscopical and microscopical morphodiagnosis to support its characterization. The microscopical morphodiagnosis was done with paradermic sections on the blades and cross sections on the blades and petioles followed by clarification and coloring with safranin and safrablue, respectively, and examined by optical microscopy. Cissampelos sympodialis has peltate leaves with deltoid blades with actinodromous -brochidodromous nervation, and the petioles are swollen at the extremities. The epidermis is hipostomatic with anticlinal walls of epidermal cells waved in the upper surface and irregularly sinuate to wavy on the lower surface. The mesophyll is dorsiventral and the vascular system of the petiole is formed by a ring of 6-7 free collateral bundles. Sparce idioblasts of prismatic crystals in parenchyma of petiole were observed. The morphology of the leaves and the anatomy of epidermis are distinguishing characters of Cissampelos sympodialis.