This monographic study of the New World genus Saba! (Arecaceae: Coryphoideae) recognizes 15 species. In addition to defining species limits and distributions, the study addresses broader questions concerning likely modes of speciation in the group and biogeographic radiation. The systematic treatment incorporates results from extensive field work and studies of leaf anatomy and flavonoid phytochemistry, ecology and biogeography, and morphology. Distribution maps and a key to the taxa are provided. Solutions are offered for the many nomenclatural problems that existed in the genus. A phylogenetic hypothesis, the first for the genus, is proposed. Moreover, phytochemical and anatomical features are examined in an ecological perspective, and hypotheses about their function and evolutionary significance are presented.
Allozyme data, combined with traditional morphological and anatomical data, were used to evaluate the genetic status of the island endemic, Cercocarpus traskiae (Catalina mahogany). Comprising only seven adult plants and close to 70 seedlings, C. traskiae is confined to Wild Boar Gully on the southwest side of Santa Catalina Island in Los Angeles County, California Electrophoretic examination of 22 enzyme loci revealed that all but two of the seven adult C. traskiae trees were unique allozymically. Furthermore four of the seven C. traskiae individuals were morphologically and/or anatomically intermediate between “true”C. traskiae and the more abundant Cercocarpus species on Santa Catalina, C. betuloides var, blancheae. Further electrophoretic analyses revealed that two of these four individuals possessed an additive “hybrid” enzyme phenotype indicating that these individuals were hybrid. Twenty‐five of the seedlings were also assayed but none of the seedlings displayed hybrid enzyme phenotypes. Given the evidence for hybridization described herein, we make two suggestions to enhance the long‐term preservation of C. traskiae. First, it may be desirable to eliminate the single C. betuloides var.: blancheae individual in Wild Boar Gully. Second, we suggest that established cuttings of true C. traskiae be transplanted to areas on Santa Catalina where the probability of hybridization is minimal Our data further demonstrate that accurate taxonomic identification and an understanding of population genetic structure are necessary for the enlightened management of small relict populations or island endemics.
Premise of research. Salvia is one of the most species-rich genera in the world. Its outstanding diversity and subcosmopolitan distribution have prevented the preparation of a modern comprehensive monograph and reevaluation of its classification. As phylogenetic efforts advance to untangle the evolutionary relationships of Salvia, the need for a solid taxonomic footing is increasingly imperative. Accordingly, we present an updated checklist of the species richness and distribution of Salvia subg. Calosphace, which constitutes more than half of the diversity of the genus. Methodology.A preliminary checklist of the species of Salvia subg. Calosphace was compiled through examination of the literature and online databases; this was revised and discussed by the authors in order to retrieve a consensus list. The distribution of each species by country or territory as well as by biome was also recorded from the sources consulted; affinities in composition were visualized with the unweighted pair group method with arithmetic mean based on a dissimilarity matrix (Sørensen's index).Pivotal results. Salvia subg. Calosphace comprises 580 species; 30 were qualified as unresolved and require further analysis. The countries with the highest species richness are Mexico (295 spp.), Peru (77 spp.), Colombia (60 spp.), Brazil (58 spp.), Guatemala (49 spp.), and Ecuador (41 spp.). The affinity in species composition between countries and between biomes is explained mainly by geographical proximity.Conclusions. The updated list of the species of Salvia subg. Calosphace will help to guide sampling for phylogenetic analyses, enabling the achievement of a more stable and solid phylogenetic hypothesis. At the same time, it is a potentially important tool for underpinning discussions toward a new sectional classification of the lineage.
Litter-trapping plants have specialized growth habits and morphologies that enable them to capture falling leaf litter and other debris, which the plants use for nutrition after the litter has decayed. Litter is trapped via rosettes of leaves, specially modified leaves and/or upward-growing roots (so-called 'root baskets'). Litter-trappers, both epiphytic and terrestrial, are found throughout the tropics, with only a few extra-tropical species, and they have evolved in many plant families. The trapped litter mass is a source of nutrients for litter-trapping plants, as well as food and housing for commensal organisms. Despite their unique mode of life, litter-trapping plants are not well documented, and many questions remain about their distribution, physiology and evolution.-
The conservation status of 134 species, subspecies and varieties of West Indian palms (Arecaceae) is assessed and reviewed, based on field studies and current literature. We find that 90% of the palm taxa of the West Indies are endemic. Using the IUCN Red List categories one species is categorized as Extinct, 11 taxa as Critically Endangered, 19 as Endangered, and 21 as Vulnerable. Fifty-seven taxa are classified as Least Concern. Twenty-five taxa are Data Deficient, an indication that additional field studies are urgently needed. The 11 Critically Endangered taxa warrant immediate conservation action; some are currently the subject of ex situ and in situ conservation projects in the region’s botanical gardens. We recommend that preliminary conservation assessments be made of the 25 Data Deficient taxa so that conservation measures can be implemented for those facing imminent threats.
ABSTRACfQualitative and quantitative wood features are reported for 38 species representing 22 genera, including the scandent genera Mendoncia and Thunbergia. Woods of Acanthaceae are characterized by relatively narrow vessels with simple perforation plates and alternate lateral wall pitting, septate libriform fibers, scanty vasicentric axial parenchyma, rays both multiseriate and uniseriate, erect ray cells abundant in rays (some species rayless or near-rayless), numerous small crystals or cystoliths in ray cells in a few genera (first documented reports of both characters in woods of Acanthaceae), and nonstoried structure. This constellation of features is very closely matched by woods of Gesneriaceae, Scrophulariaceae, Pedaliaceae, Martyniaceae, Bignoniaceae, and Myoporaceae (families listed in order ofdecreasing resemblance). Narrowness ofvessels in tropical Acanthaceae appears related to understory ecology. A few species in warm and seasonally dry areas have narrow, short vessel elements numerous per unit transection. Vasicentric tracheids occur in two nonscandent genera in dry areas. Vessel grouping is roughly proportional to dryness of habitat. Thunbergia alata, T. laurifolia, and all collections of Mendoncia have interxylary phloem (first report for Mendoncia). That feature, plus presence of occasional acicular crystals in rays and axial parenchyma and presence of large gelatinous fibers in phloem ally Mendoncia closely with Thunbergia, and Mendonciaceae is not justified for this and other reasons. Species of Thunbergia differ among themselves, and T. erecta and T. holstii resemble shrubby Acanthaceae more than they do Mendoncia in wood features. Thunbergia thus should not be segregated from Acanthaceae.
The Caribbean Islands are one of the world's 34 biodiversity hotspots, remarkable for its biological richness and the high level of threat to its flora and fauna. The palms (family Arecaceae) are well represented in the West Indies, with 21 genera (three endemic) and 135 species (121 endemic). We provide an overview of phylogenetic knowledge of West Indian Palms, including their relationships within a plastid DNA-based phylogeny of the Arecaceae. We present new data used to reconstruct the phylogeny of tribe Cryosophileae, including four genera found in the West Indies, based on partial sequences of the low-copy nuclear genes encoding phosphoribulokinase (PRK) and subunit 2 of RNA polymerase II (RPB2). Recently published phylogenetic studies of tribe Cocoseae, based on PRK sequences, and tribes Cyclospatheae and Geonomateae, based on PRK and RPB2 sequences, also provide information on the phylogenetic relationships of West Indian palms. Results of these analyses show many independent origins of the West Indian Palm flora. These phylogenetic studies reflect the complex envolutionary history of the West Indies and no single biogeographical pattern emerges for these palms. The present day distributions of West Indian palms suggest complicated evolutionary interchange among islands, as well as between the West Indies and surrounding continents. We identified six palm lineages that deserve conservation priority. Species-level phylogenies are needed for Copernicia, Sabal, and Roystonea before we can build a more complete understanding of the origin and diversification of West Indian palms.Resumen Las Islas del Caribe constituyen uno de los 34 "hotspots" de biodiversidad del mundo, notables por su riqueza biológica y el alto grado de amenaza de su flora y fauna. La familia Arecaceae esta bien representada en Las Antillas con 21 géneros (tres endémicos) y 135 especies (121 endémicas). Presentamos una síntesis del conocimiento filogénetico de las palmas de Las Antillas incluyendo su posición dentro de la filogenia de la familia Arecaceae basada en ADN cloroplástico. Construímos una nueva filogenia para la tribu Cryosophileae, Bot. Rev. (2008) 74:78-102
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.