Two new species of Verbesina section Ochractinia (Asteraceae) from South America

Two new species ofVerbesina sectionOchractinia are described:V. quetamensis from Colombia, a member of theV. synethes species group andV. carangolensis from Brazil, most closely allied withV. acuminata.     

Eudesmane derivatives from Verbesina species

The investigation of seven Verbesina species afforded, in addition to known compounds, several new eudesmane and germacrane derivatives, all bearing a cinnamate or derivatives as residue. Furthermore, a new bisabolene aldehyde and two acetophenone derivatives were isolated. The structures were elucidated mainly by spectroscopic methods and some chemical transformations. The chemotaxonomic situation is discussed briefly.     

Sectional limits and phylogenetic considerations in Carex section Ceratocystis (Cyperaceae)

Carex L. sectionCeratocystis Dumort. is distinct from the closely related sectionSpirostachyae (Drejer) L. Bailey. Differences in pistillate spike morphology, achene shape, and perigynium epidermis are augmented by chemical, cytological, and micromorphological evidence. Character compatibility analysis has been used to reconstruct the phylogenetic history of the sedges in sectionCeratocystis. The resulting network is shown to be robust when tested with cytological, ecological, and micromorphological data not included in its construction. Agmatoploidy has been the dominant process of chromosomal evolution in the section.     

Neue sesquiterpene aus Verbesina occidentalis

The investigation of the aerial parts of V. occidentalis affords six new sesquiterpenes their structures being elucidated by spectroscopic methods. All compounds are derived from muurolene. V. enceloides contains simple compounds, only one being new, which is closely related to a diacetate from Amphiachyris amoenum.     

Three new species of Dalechampia (Euphorbiaceae) from Venezuelan Guayana

Three new species ofDalechampia are described from the Guayanan region of Venezuela.Dalechampia attenuistylus belongs to sectionRhopalostylis and may be most closely related toD. parvibracteata Lanj.Dalechampia megacarpa belongs to sectionDioscoreifoliae, although it is not especially close to any species in the section.Dalechampia papillistigma is also an isolated member of sectionDioscoreifolieae.     

Five new species of calea (Compositae: Heliantheae) from planaltine Brazil

Described from the Planalto of Brazil are:Calea quadrifolia, C. heteropappa, andC. abbreviata of sectionMeyeria,C. intermedia of sectionLemmatium, andC. lutea of sectionCalea. The relationships of each are discussed and a key to the nearest relatives of each is provided. Additionally, all butC. intermedia are illustrated.     

Synopsis ofVerbesina sect.Ochractinia (Asteraceae)

A taxonomic revision ofVerbesina sect.Ochractinia is presented. 40 species plus 7 additional infraspecific taxa are recognized. A table of the distribution of the species, key to the species and synonymy are included. Relationships to other sections ofVerbesina and species relationships within sect.Ochractinia are discussed.     

Three new species of Dalechampia (Euphorbiaceae) from Brazil

Dalechampia fernandesii, from Ceará, belongs to sectionTiliifoliae and is related toD. affinis andD. tiliifolia.Dalechampia armbrusteri, of subsectionDalechampia, from Bahia, is close toD. brownsbergensis of Suriname but has well developed resiniferous bractlets.Dalechampia viridissima, from Bahia and Espírito Santo, is an isolated species with the 3-lobed leaves of species in sectionDalechampia subsectionDalechampia but the reduced indumentum and greenish bracts of species in sectionTriphyllae.     

Serological comparisons of seed proteins of some representatives of the genusAllium

Results obtained by comparison of similarity of seed protein spectra of 15 species of the genusAllium (in 22 samples) by means of immunochemical methods more or less correspond to the contemporary division of this genus. Species belonging to the sectionCepa (according to Vvedenskiy) andPhyllodolon have very similar spectra, which suggests that they either should be allocated to one sectionCepa or to two subsections (Cepa andPhyllodolon). Species belonging to the subgenusRhizirideum considerably differ in seed proteins. The investigated species of the subgenusMelanocrommyum show the most distinct spectrum of all the other analyzed representatives, less marked differences were found in the case of the representatives of the subgenusAllium.     

Chrysothamnus eremobius (Asteraceae): A new species from Nevada

Chrysothamnus eremobius, endemic to mountains of southern Nevada, is formally described and illustrated. Morphological and anatomical comparisons are made to related taxa. The new species has many features likePetradoria discoidea (=C. gramineus). Although it bears some similarity toC. depressus andC. vaseyi of sectionPulchelli, C. eremobius is better placed in sectionChrysothamnus nearC. viscidiflorus.     

Three new species of melastomataceae from the southeastern Atlantic Forest of Brazil

Three species are described here that occur in montane and high-montane forests in Southeastern Brazil.Miconia shepherdii belongs to sectionGlossocentrum and occurs on the Serra da Mantiqueira, on the border between the states of São Paulo, Minas Gerais, and Rio de Janeiro.Miconia kollmannii belongs to sectionHypoxanthus (formerChaenanthera) and occurs in the state of Espírito Santo.Ossaea suprabasalis was also collected in the state of Espírito Santo.     

A new species of penstemon (Scrophulariaceae) from southwestern Utah

Penstemon ammophilus, an endemic to Canaan Moutain in Washington Co., Utah, is described and illustrated. On the basis of anther characteristics it is placed in sectionGlabri, seriesVirgati, where it nearly links the group to sectionCristati. It is distinct from all the species of both sections with its peculiar papillose-glandular pubescence.     

Elemanolides from Verbesina seattonii

Two novel sesquiterpene lactones were isolated from Verbesina seattonii. Their structures were elucidated as elemanolides possessing an intramolecular hemiacetal function on the basis of an extensive spectral analysis and crystal structure determination.     

Studies in the cyperaceae of Thailand

Ten species ofCarex and one species ofKobresia from Thailand are taxonomically discussed, and some new range extensions into Thailand are noted. Described as new areCarex subinclinata andC. thailandica, both belonging to the sectionIndicae, andC. speciosa ssp.latifolia of the sectionRadicales. Two new combinations proposed areCarex helferi ssp.mapanifolia, andC. speciosa ssp.platyrhina.     

Three new species of Elleanthus (Orchidaceae) from Central America

Elleanthus stolonifer andE. tillandsioides are new species in theE. poiformis complex of sectionChloidelyna.Elleanthus lentii is a new species in sectionStachydelyna. Elleanthus stolonifer is widespread in the mountains of Costa Rica and Panama;E. tillandsioides is found only in the lowland forests of southeastern Costa Rica;E. lentii is limited to the Cordillera de Guanacaste of Costa Rica.     

Oreobroma megarhizum is a Calandrinia of section Acaules (Portulacaceae)

Oreobroma megarhizum is reassigned to the genusCalandrinia and placed in the sectionAcaules. The biogeographic and evolutionary consequences are evaluated in relation toOreobroma (Lewisia) andCalandrinia distribution patterns.     

Molecular evidence does not support the current division of Orthotrichum subgenus Gymnoporus

Eight Orthotrichum species of subgenus Gymnoporus were compared using the internally transcribed spacer regions-1 and -2 and the chloroplast trnH-psbA region. A phylogenetic analysis did not reflect the current division of this subgenus into sections Affinia and Leiocarpa. The investigated sequences revealed a close relationship between O. striatum, a typical species of section Leiocarpa and O. affine, a typical species of section Affinia. An easily distinguishable group was formed by samples of the dioecious O. lyellii, placed into section Leiocarpa. A large number of fixed differences between O. lyellii and other species of subgenus Gymnoporus raises doubts concerning its position within this subgenus. No marker mutations enabling to differentiate O. fastigiatum from O. affine have been found. In absence of such mutations for O. affine and O. striatum, the status of O. fastigiatum cannot be determined unambiguously.     

Eudesmane triols from Verbesina virgata

Chemical study of Verbesina virgata collected in several localities afforded two eudesmane triols as 4-cinnamates. Their structures were determined by chemical and spectroscopic means. The structure and stereochemistry of one of the triols was confirmed by X-ray crystallography.