Life Sciences Commons^™

Shifting Paradigms In Island Biology, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

The ease of travel by jet aircraft has opened up island areas not only for study but also for introduction of weeds, pests, and pathogens. We are at a critical juncture in the study of island organisms, which have become more accessible at the same time that they are vanishing. With the urgency for study of island organisms, we have many new tools, especially molecular ones, which have validated the existence of long-distance dispersal in unexpected ways. These tools, together with the ease of staying for longer periods on islands, have permitted us to understand many aspects of evolutionary adaptation …

Plant Conservation In The Juan Fernandez Archipelago, Chile, Tod F. Stuessy, Ulf Swenson, Daniel J. Crawford, Gregory Anderson, Mario Silva O.

Aliso: A Journal of Systematic and Floristic Botany

Oceanic archipelagos often hold very specialized floras with high degrees of endemism. These floras are frequently highly vulnerable to disturbance by natural causes and human intervention. The Juan Fernandez Islands (Chile) in the Pacific Ocean are a small archipelago of only three islands. Since discovery in 1574 by Juan Fernandez, human activities have altered floristic composition and survival circumstances of the endemic species. In this paper we document past and present means of disturbance, both anthropogenic and natural, which have influenced the native vegetation. The most destructive past activities have been logging and .introduction of animals and plants, both deliberately …

Landscape Management Challenges On The California Channel Islands, William L. Halvorson

Aliso: A Journal of Systematic and Floristic Botany

Managing for sustained biodiversity and restoration of natural habitat has become increasingly important over the last two decades, first as mitigation for development (especially in wetlands), and , more recently in natural areas. The latter has come about as land managing agencies like the Department of Defense and Bureau of Land Management have seen the need to reverse the impact of past land uses and agencies like the National Park Service and The Nature Conservancy have taken on the responsibility for less-than-pristine lands.

On the California Channel Islands, the need for restoring and managing biodiversity is great, but this restoration …

Conserving Plants As Evolutionary Entities: Successes And Unanswered Questions From New Zealand And Elsewhere, Ian A. E. Atkinson

Aliso: A Journal of Systematic and Floristic Botany

Saving a species from extinction may not insure that its future will continue as before, even when the surviving population is in a wild habitat. Former selection forces may be missing or replaced by others so that the species develops along a different evolutionary pathway. Such disruption of evolutionary direction may be particularly important for island taxa given that modification by humans and their introduced organisms is making many islands more similar to continental habitats. In restoring habitats for island species, special attention should therefore be given to identify ing the major selective forces likely to have been operating during …

Plant Conservation In A Changing World, Peter H. Raven

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Wood Anatomy Of Resedaceae, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Quantitative and qualitative data are presented for seven species of four genera of Resedaceae. Newly reported for the family are helical striations in vessels, vasicentric and marginal axial parenchyma, procumbent ray cells, and perforated ray cells. Wood features of Resedaceae may be found in one or more of the families of Capparales close to it (Brassicaceae, Capparaceae, Tovariaceae). Lack of borders on pits of imperforate tracheary elements is likely a derived character state. Wood of Reseda is more nearly juvenile than that of the other genera in ray histology; this corresponds to the herbaceousness of Reseda. The quantitative features …

Wood Anatomy Of Portulacaceae And Hectorellaceae: Ecological, Habital, And Systematic Implications, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative wood data are given for 13 species of 10 genera of Portulacaceae (secondary xylem from additional species of Anacampseros and Lewisia were studied but not quantitatively analyzed). Most Portulacaceae show modifications that can be related to the succulent habit, including wide, tall rays mostly composed of thin-walled cells; total or partial substitution of axial parenchyma for libriform fibers ; and modified patterns of pitting on lateral walls of vessels. Pseudoscalariform pitting is more common in Portulacaceae than in other dicotyledon families. In vessels of Anacampseros wood, wide helical bands of secondary wall materi al are present. Similar …

Laboubeniales On Semiaquatic Heteroptera. Vii. Addenda To Species Of Triceromyces On Hydrometridae And Further Observations On Dioecism In The Order, Richard K. Benjamin

Aliso: A Journal of Systematic and Floristic Botany

Four new species of Triceromyces (Laboulbeniales) parasitic on Hydrometra (Heteroptera: Hydrometridae) were described and aspects of their morphology and development were discussed and illustrated with line drawings. Two of the species, T. floridanus and T. elongatus, are monoecious; T. floridanus, known only from Florida, U.S.A., has features allying it with T. elongatus, which ranges from Madagascar and Kenya in Africa to India, Indonesia, and Sri Lanka in Asia. The other two undoubtedly closely related species, T. lithophilus and T. terrestris, are dioecious and parasitize two closely related endemic species of Hydrometra thriving in a small region …

A Floristic Study In The Diamond Creek Drainage Area, Gila National Forest, New Mexico, Eric H. Roalson, Kelly W. Allred

Aliso: A Journal of Systematic and Floristic Botany

The Diamond Creek drainage is one of the major watershed systems of the Gila National Forest in southwestern New Mexico. The purposes of this study were to catalog the vascular plants of a portion of this drainage area, describe the vegetation zones, locate any threatened, endangered, or sensitive plant species, and assess plant regeneration in areas that have been burned. The study area is located in the eastern portion of the Gila National Forest along the Black Range in the northwest corner of Sierra County. It covers approximately 5600 hectares (14000 acres) and ranges in elevation from 2250 to 3000 …

Wood Anatomy Of Calyceraceae With Reference To Ecology, Habit, And Systematic Relationships, Sherwin Carlquist, Melanie L. Devore

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative data are presented for secondary xylem of 14 species of four genera of Calyceraceae; root wood is studied for acaulescent perennials and one annual. The wood anatomy of most species of Calycera has character states identical to those seen in wood of most Asteraceae (including phylads of Asteraceae thought to be basic in that family). Goodeniaceae have two features (tracheids, diffuse parenchyma) more primitive than corresponding conditions in Asteraceae and CaIyceraceae according to traditional criteria. Diversity in wood anatomy within Calyceraceae is explainable in terms of adaptation to particular ecological conditions. Although woods of the family as …

Nomenclatural Changes In Polemoniaceae, J. Mark Porter

Aliso: A Journal of Systematic and Floristic Botany

Recent molecular phylogenetic analyses of nuclear, chloroplast and mitochondrial DNA of Polemoniaceae have prompted a reexamination of morphological data and a reassessment of current taxonomy. These studies prompt several nomenclatural changes in the family. Eight taxa formerly included in Gilia section Giliastrum are transferred to the genus Giliastrum. In addition, two new tribes of Polemoniaceae are recognized.

Phylogeny And Adaptation In The Encelia Alliance (Asteraceae: Helliantheae), Curtis Clark

Aliso: A Journal of Systematic and Floristic Botany

The three related genera Encelia, Enceliopsis, and Geraea comprise the alliance. The first consists primarily of shrubs and the latter two of herbaceous perennials and an annual. With the exception of two Encelia species of arid South America, all inhabit southwestern North America. Enceliopsis and Geraea are sister groups, and together form the sister group to Encelia, which includes two major clades. Especially in Encelia, there are diverse morphologies and a variety of ecological strategies marked by differences in habitat, vestiture, water balance, and photosynthetic parameters. The North American species of all three genera are obligate …

A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos

Aliso: A Journal of Systematic and Floristic Botany

Pinus devoniana, a member of the Pinus montezumae complex (Ponderosae) of Mexico and Central America occurs as scattered populations from the western states of Jalisco and Nayarit to Chiapas in the east. Populations within regions, i.e., western or eastern Mexico, are separated by from 75 to 300 km, while the eastern and western populations are more that 700 km apart. Levels of gene flow between populations within regions and between eastern and western Mexico are assessed using the paternally inherited chloroplast genome as a marker. Twenty-five polymorphic restriction chloroplast sites were found in the 175 individuals surveyed; …

Cladistic Parsimony Analysis Of Internal Transcribed Spacer Region (Nrdna) Sequences Of Bouteloua And Relatives (Gramineae: Chloridoideae), J. Travis Columbus, Michael S. Kinney, Rashmi Pant, Maria Elena Siqueros Delgado

Aliso: A Journal of Systematic and Floristic Botany

Chloridoideae) employing cladistic parsimony analysis of nuclear ribosomal internal transcribed spacer region (ITS1 + 5.8S + ITS2) DNA sequences. Included were Aegopogon (2 of 4 species), Bouteloua (34 of 42), Buchloë (1 of 1), Buchlomimus (1 of 1), Cathestecum (2 of 4), Cyclostachya (1 of 1), Griffithsochloa (1 of 1), Hilaria (1 of 7), Opizia (2 of 2), Pentarrhaphis (2 of 3), Pleuraphis (2 of 3), Pringleochloa (1 of 1), Soderstromia (1 of 1), and five outgroup genera/species for a total of I8 genera, 56 species, and ten varieties. In all, the ITS region of 72 plants was sequenced and …

Plant Systematics: Beginnings And Endings, Billie L. Turner

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Phylogenetic Relationships Of Polemoniaceae: Inferences From Mitochondrial Nad1b Intron Sequences, J. Mark Porter, Leigh A. Johnson

Aliso: A Journal of Systematic and Floristic Botany

The most recent assessments of phylogenetic relationships and diversification in the flowering plant family Polemoniaceae have relied on nuclear ribosomal and chloroplast DNA sequences. We employed the mitochondrial nad1b intron, located within the second transcription unit of the first subunit of NADH dehydrogenase, for phylogenetic inference. Maximum parsimony analysis of these data provided evidence that Polemoniaceae are more closely related to families Fouquieriaceae, Diapensiaceae, Styracaceae, and Primulaceae than to families of the Solananae, where it has been classified. Fouquieriaceae are inferred to be the sister group of Polemoniaceae; however, when indels are treated as additional characters and given twice the …

Arabis Hirshbergiae (Brassicaceae), A Narrow Endemic From The Cuyamaca Mountains, San Diego County, California, Steve Boyd

Aliso: A Journal of Systematic and Floristic Botany

A narrow endemic from the Cuyamaca Mountains of southern California is described as a new species, Arabis hirshbergiae. Closest relationships appear to be with A. johnstonii and A. parishii, also narrow endemics from the San Jacinto and San Bernardino Mountains respectively. All three species are associated with pebble plain habitats in montane areas characterized by relatively gentle relief compared with surrounding canyons and ridge systems.

New Names And Combinations In Encelia Frutescens Sensu Lato (Asteraceae: Heliantheae, Curtis Clark

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Cheilanthoid Ferns (Pteridaceae: Cheilanthoideae) In The Southwestern United States And Adjacent Mexico-A Molecular Phylogenetic Reassessment Of Generic Lines, Gerald J. Gastony, David R. Rollo

Aliso: A Journal of Systematic and Floristic Botany

Cheilanthoids are the most commonly encountered fern species of the arid southwest and other xeric habitats throughout the world. Cheilanthes, Notholaena, Pellaea, and Bommeria are the best known southwestern genera, but some authors recognize segregate genera such as Argyrochosma, Aspidotis, Astrolepis, and Pentagramma. Others reject distinctions among some of these genera as artificial, leaving cheilanthoid generic concepts in a state of flux. This unsettled taxonomy is often attributed to morphological homoplasy associated with adaptation to xeric habitats, suggesting the need for new analyses that do not depend on potentially misleading morphology. Nucleotide sequences …

Ecophysiological Observations On Lane Mountain Milkvetch, Astragalus Jaegerianus (Fabaceae), A Proposed Endangered Species Of The Mojave Desert, Arthur C. Gibson, M. Rasoul Sharifi, Philip W. Rundel

Aliso: A Journal of Systematic and Floristic Botany

Astragalus jaegerianus, the Lane Mountain milkvetch, a perennial herbaceous legume, is a rare and very narrow endemic of the central Mojave Desert in San Bernardino County, California, and currently proposed to be listed as an endangered species. This herb grows in the protection of low shrubs. Anatomical observations revealed that leaflets are amphistomatic and have isolateral mesophyll, typical of full-sun desert leaves, and the green stem is an important photosynthetic organ, having abundant stomata and a cylinder of cortical chlore nchyma. Ecophysiological studies showed that this species requires high PFD (1400-1500 μmol m^-2s^-1) to achieve …

Introduction, Edward L. Schneider, Roy L. Taylor

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Aliciella, A Recircumscribed Genus Of Polemoniaceae, J. Mark Porter

Aliso: A Journal of Systematic and Floristic Botany

Recent phylogenetic analyses within Polemoniaceae have provided evidence that the current circumscriptionof Gilia recognizes and gives taxonomic status to a polyphyletic assemblage of species. As a first step in rectifying this problem, the genus Aliciella Brand (Polemoniaceae) is resurrected and recircumscribed to include Gilia section Giliandra and Gilia subgenus Gilmania sensu Mason & Grant, a monophyletic (=holophyletic) group as here described. Twenty-one recombinations are proposed: Aliciella cespitosa, A. formosa, A. haydenii, A. haydenii subsp. crandallii, A. heterostyla, A. humillima, A. hutchinsifolia, A. latifolia, A. latifolia subsp. imperialis. A. leptomeria. A. lottiae. A. mcvickerae.A. micromeria. A. nyensis, A. pentstemonoides, A. …