David J. Keil

Diploid and polyploid cytotype distribution in Melampodium cinereum and M. leucanthum (Asteraceae, Heliantheae)

Previous chromosomal studies within Melampodium (Asteraceae, Heliantheae) of Mexico and Central America have documented chromosome numbers n = 9, 10, 11, 12, 18, 20, 23, 25 ± 1, 27, 30, and 33. Some species also have been shown to exhibit infra- and interpopulational polyploidy. The presence of cytotype mixtures is especially pronounced in the white-rayed complex, which occurs in the southwestern United States and adjacent Mexico. This group includes M. cinereum (n = 10 and 20), M. leucanthum (n = 10 and 20), and M. argophyllum (n = 30). Cytotype distribution has been newly analyzed in 415 plants from 152 populations and added to existing data from 185 plants from 113 populations, yielding information from a total of 600 individuals from 265 populations. Within M. cinereum and M. leucanthum are parapatric distributions of cytotypes, with tetraploids centered in the eastern and diploids in the western portions of their ranges. Tetraploids are most likely of autopolyploid origin, forming recurrently, with adaptations that allow colonization and establishment in new ecological regions. Contact zones are relatively narrow and only two triploid individuals have been detected. The tetraploid cytotypes probably extended eastward into central and southern Texas to the natural barriers at the edge of the Edwards Plateau in M. leucanthum and the low sandy plains in M. cinereum. The hexaploid M. argophyllum is interpreted as a relict surviving in the low mountains of northern Mexico; it may be an allopolyploid of hybrid origin between ancestors of the evolutionary lines that eventually yielded M. cinereum and M. leucanthum.

Distribution of acetylenic thiophenes in the pectidinae

Abstract The distribution and quantitative significance of biosynthetically related di- and ter-thiophenes from 27 species representing seven genera of the Pectidinae (Heliantheae) was investigated by reverse-phase HPLC. Adenophyllum, Chrysactinia and Nicolletia , three previously unstudied genera, were found to contain thiophenes for the first time. Four derivatives, 5-(4-hydroxy-1-butenyl)-2,2′-bithiophene ( 1 ), 5-(4-acetoxy-1-butenyl)-2,2′-bithiophene ( 2 ), 5-(3-buten-1-ynyl)-2,2′-bithiophene ( 3 ) and 2,2′:5′,2″-terthiophene ( 4 ) were common constituents in most species of Adenophyllum, Chrysactinia, Dyssodia, Hymenatherum, Nicolletia and Porophyllum . One additional compound, 5-methyl-2,2′:5′,2″-terthiophene ( 5 ), was also present in extracts of Adenophyllum, Dyssodia and Hymenatherum , but was not detected in any other genus. Acetylenic thiophenes were not found in any of the 18 species of Pectis examined.

Plant Photosensitizers: A Survey of Their Occurrence in Arid and Semiarid Plants From North America

Various plants native to arid and semiarid habitats throughout the southwestern United States, Baja California, and northern Mexico were bioassayed for phototoxic natural products. Approximately 115 species representing 57 genera and eight plant families were assayed for phototoxic activity by standard antimicrobial techniques usingEscherichia coli andSaccharomyces cerevisiae. Phototoxic constituents were extracted from numerous members in the Asteraceae (Compositae) and occurred with highest frequency among species of the subtribe Pectidinae (tribe Heliantheae). Extracts ofPectis, the largest genus in the Pectidinae, had substantial light-activated biocidal action despite the paucity of acetylenic thiophenes, the phototoxins characteristic of most other genera in the subtribe. Leaf resin from the creosote bush [Larrea tridentata (Sesse & Mol. ex DC.) Coville; Zygophyllaceae], a dominant desert shrub, possessed potent antimicrobial activity in the absence of light; however, the toxicity of this extract was slightly enhanced in the presence of UVA irradiation. Phototoxic antimicrobials were not detected in extracts of selected species from the Asclepiadaceae, Chenopodiaceae, Hydrophyllaceae, Lamiaceae, Polygonaceae, or Solanaceae.

Two New Species of Pectis (Asteraceae: Tageteae) from South America

Pectis hassleri and P. pumila are new species, the former from the Gran Chaco area of Paraguay and the latter from southwestern Ecuador and northwestern Peru. Pectis hassleri differs from P. odorata by leaves that are glandular-punctate on the adaxial as well as the abaxial surfaces, by longer and wider ligules of the ray florets, and by ray pappi of awns and shorter bristles. Pectis pumila differs from the closely related R arida by its wider leaves and by its sessile or subsessile capitula with campanulate involucres and obovate phyllaries. A hexaploid chromosome count of 2n = 361 is newly reported for P. pumila.

New Species of Pectis (Asteraceae) from the West Indies, Mexico, and South America

Four new species ofPectis are described:P. ericifolia from Barbuda,P. luckoviae from west-central Mexico,P. arida from Ecuador and Peru, andP. cajamarcana from Peru. Chromosome counts forP. ericifolia (n=48) andP. luckoviae (n=12) are presented. Relationships of the newly described taxa are discussed.

Wildflowers of Orange County and the Santa Ana Mountains

This is a remarkable publication representing a love of nature and a dedication to sharing it. The authors have assembled an information-rich guide that is profusely illustrated with diagrams, maps, and attractive and informative photographs. It is far more than a wildflower guide. The authors ‘‘know’’ Orange County and the Santa Ana Mountains region and they lovingly describe its special places, its plant life, and some of its wildlife. The introductory chapter includes engaging discussions of the geology and geography of the region, plant features, plant classification, plant names, and plant communities. A section on Watching Wildflowers includes practical tips for observing, documenting, photographing, drawing, and gardening with wildflowers plus safety tips for the outdoors. One thing I would like to have seen in the introduction is a discussion of the authors’ criteria for deciding what to include or exclude; cattails, for instance are included as wildflowers whereas rushes, with more readily recognizable floral structures, are not. I wondered about some other inclusions or exclusions as well. The book is up-to-date, following modern classifications of major plant groups and is aligned for the most part with the second edition of the Jepson Manual (Baldwin et al. 2012). Although the arrangement of taxa within major groups is mostly alphabetical the authors have, in some cases, grouped morphologically similar genera to make comparisons easier. Plant descriptions are provided at various taxonomic levels along with habitat and locality information and natural history notes. The book does not include taxonomic keys, so identifications may be a challenge to users without an acquaintance with plant families. Scientific names used in the book are, for the most part, in agreement with those in the Jepson Manual. No standardization exists, however, for common names, and thus the choice of which common names to present to the public is a challenge to authors of a book of this nature. I noted various instances where the authors and I differ in our preferred common names. In some instances the authors include more than one common name for a species. Because of the negative connotation that may accompany the word weed, the authors have avoided many common names incorporating this word—thus tarweeds become tarplants, pygmyweeds become pygmy stonecrops, etc. Common chickweed— which is indeed a weed—is unchanged. The authors provide etymologies for specific epithets and for some generic names. An unexpected, unadvertised, and most informative feature of this book is the description of guilds of animals, especially insects, that are associated with particular species or groups of plants. These are accompanied by excellent photos—often stunning close-ups of insects and informative discussions. Scientific and common names are provided for the animals along with descriptions of their interactions with the plants and other natural history notes. Following the taxonomic treatments of plants and the occasional animal guild is a discussion of Where to go Wildflower Watching. This includes maps and directions plus highlights of what may be observed. In such an urbanized area it is very useful to discover that there are so many special places to see wildflowers and other natural features. End matters include a detailed list of references used in preparation of the guide, a glossary, an index to common and scientific names of plants and animals, and an index to plant common names organized by flower color. I look forward to using this book, and I highly recommend it. The authors are to be congratulated on an outstanding achievement.

Mimicking Fire for Successful Chaparral Restoration

Abstract Following disturbance, seed pre-treatment is essential for re-establishing many species with low germination rates. However, some seeds, such as those from chaparral plants, do not respond to common horticultural treatments. Instead, methods that mimic chaparrals natural succession cues (e.g., fire) should be used to improve seed germination and restoration success. Fire effects, such as heat, charate, leachate, smoke, and/or liquid smoke, are effective in breaking long-term seed dormancy in many chaparral plants. The challenge is to break seed dormancy in a cost- and time-efficient manner that can be used in large-scale restoration projects. Results of our study show that short-term exposure (10 minutes to one hour) to liquid smoke and/or heat enhances seed germination of Adenostoma fasciculatum Hook. & Arn. (chamise), Ceanothus cuneatus (Hook.) Nutt. (buckbrush), and Salvia mellifera Greene (black sage). Chamise seeds treated with liquid smoke have the greatest percent increase of seed germination odds: 394%, from the control (P < 0.000). Buckbrush seeds treated with liquid smoke and heat have the greatest percent increase of seed germination odds: 953%, from the control (P < 0.000). Black sage seeds treated with heat have the greatest percent increase of seed germination odds: 354%, from the control (P < 0.000). Implementing these procedures in restoration may reduce the seed costs of certain species by nearly 90%.

Lectotypification of Arctostaphylos hooveri (Ericaceae)

Abstract The holotype of Arctostaphylos hooveri P. V. Wells, cited as having been deposited in the Robert F. Hoover Herbarium, California Polytechnic State University (OBI), apparently is not extant. The isotype deposited in the University Herbarium (UC) at the University of California, Berkeley (Hoover & Wells 1960 — UC 1218855) is designated as the lectotype, and the isotype in the California Academy of Science Herbarium (CAS 423565) is thereby an isolectotype. Hoover 8520 (OBI 175682) is recognized as a paratype.

Pentachaeta aurea Subsp. Allenii (Asteraceae), a New Subspecies from Orange County, California

ABSTRACT Pentachaeta aurea Nutt. subsp. allenii Keil is described as new. It is apparently endemic to southwestern Orange Co., California. Lamina tips of ray corollas of living specimens of the plants are pale yellow in early morning but turn brilliant white after 1–2 hr in sunshine; laminae of subsp. aurea are solid yellow.