http://amborella.net/2010PlantSystematics/DATA/3-24-APG%202003%20Bot%20J%20Linn%20Soc%20APGII.pdf

An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II

The Vegetation of South Africa, Lesotho and Swaziland

Thome, Robert F. (Rancho Santa Ana Botanic Garden, Claremont, CA 91711). Classification and geography of the flowering plants. Bot. Rev.58(3): 225–348. 1992.—This treatment of the flowering plants is the latest revision of my classification of the Class Angiospermae and replaces my 1983 and more recent 1992 synopses. An update is necessary because so much new information has been published in the last decade pertinent to the classification of the flowering plants. About 870 such recent books, monographs, and other botanical papers are cited in the Introduction, listed primarily by the botanical discipline that they represent. Also considerable changes in my classification have been necessitated by my narrowed family- and ordinal-gap concepts, acceptance of the ending “-anae” for superorders in place of the traditional but inappropriate “-iflorae,” and acceptance of more prior or more widely used names for the categories above the family. A new phyletic “shrub” replaces earlier versions, and attempts to indicate visually relative sizes and relationships among the superorders, orders, and suborders. One table includes a statistical summary of floweringplant taxa: ca. 233,900 species of 12,650 genera, 437 families, and 708 subfamilies and undivided families in 28 superorders, 71 orders, and 71 suborders of Angiospermae. Three other tables summarize the known indigenous distribution of the families and subfamilies of angiosperms about the world. The synopsis lists the flowering plant taxa from the class down to the subfamily (and in Asteraceae down to the tribe) with indication of the degree of confidence I place in the circumscription and placement of each category above the subfamily, the best available estimates of the number of genera and species for each category, and the known indigenous distribution of each subfamily and family. Table V lists alphabetically the geographical abbreviations used in the synopsis. The extensive bibliography of recent literature should be helpful to those persons interested in the classification of the flowering plants.

https://link.springer.com/content/pdf/10.1007/BF02858611.pdf

Classification and geography of the flowering plants

Physical dormancy (PY) is caused by a water-impermeable seed or fruit coat. It is known, or highly suspected, to occur in nine orders and 15 families of angiosperms (sensuAngiosperm Phylogeny Group 1998), 13 of which are core eudicots. The Zingiberales is the only monocot order, and Cannaceae (Canna) the only monocot family, in which PY is known to occur. Six of the nine orders, and 12 of the 15 families, in which PY occurs are rosids. Furthermore, six of the families belong to the Malvales. The water-impermeable palisade layer(s) of cells are located in the seed coats of 13 of the families, and in the fruit coats of Anacardiaceae and Nelumbonaceae. In all 15 families, a specialized structure is associated with the water-impermeable layer(s). The breaking of PY involves disruption or dislodgment of these structures, which act as environmental ‘signal detectors’ for germination. Representatives of the nine angiosperm orders in which PY occurs had evolved by the late Cretaceous or early Tertiary (Paleogene). Anatomical evidence for PY in fruits of the extinct species Rhus rooseae (Anacardiaceae, middle Eocene) suggests that PY had evolved by 43Ma, and probably much earlier. We have constructed a conceptual model for the evolution of PY, and of PY+ physiological dormancy (PD), within Anacardiaceae. The model begins in pre-Eocene times with an ancestral species that has large, pachychalazal, non-dormant (ND), recalcitrant seeds. By the middle Eocene, a derived species with relatively small, partial pachychalazal, orthodox seeds and a water-impermeable endocarp (thus PY) had evolved, and by the Oligocene, PD had been added to the seed (true seed + endocarp) dormancy mechanism. It is suggested that climatic drying (Eocene), followed by climatic cooling (Eocene–Oligocene transition), were the primary selective agents in the development of PY. An evolutionary connection between PY and recalcitrance is suggested by the relatively high concentration of these two character states in the rosids. Phylogenetic data and fossil evidence seem to support the PY→(PY+PD) evolutionary sequence in Anacardiaceae, which also may have occured in Leguminosae.

Taxonomy, anatomy and evolution of physical dormancy in seeds

An updated inventory of the vascular flora alien to Italy, providing details on the occurrence at regional level, is presented. The checklist includes 1597 species, subspecies, and hybrids, distributed in 725 genera and 152 families; 2 taxa are lycophytes, 11 ferns and fern allies, 33 gymnosperms, and 1551 angiosperms. 157 taxa are archaeophytes and 1440 neophytes. The alien taxa currently established in Italy are 791 (570 naturalized and 221 invasive), while 705 taxa are casual aliens, 4 are not assessed, 7 are of unknown regional distribution, 47 have not been confirmed in recent times, 3 are considered extinct or possibly extinct in the country, and 40 are doubtfully occurring in Italy. This checklist allows to establish an up-to-date number (9792) of taxa constituting the whole (native and alien) Italian flora.

/pdf/an-updated-checklist-of-the-vascular-flora-native-to-italy-2tuf9mb3d4.pdf

An updated checklist of the vascular flora native to Italy

Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world’s largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity.

/pdf/evolutionary-history-and-leaf-succulence-as-explanations-for-2v88yp3u3p.pdf

Evolutionary history and leaf succulence as explanations for medicinal use in aloes and the global popularity of Aloe vera

An inventory of Vhavenda useful plants

Trends in the evolution of dicotyledonous seeds based on character associations, with special reference to pachychalazy and recalcitrance

Documented Utility and Biocultural Value ofAloeL. (Asphodelaceae): A Review. The genus Aloe L. (Asphodelaceae) comprises 548 accepted species, of which at least one-third are documented as having some utilitarian value. The group is of conservation concern due to habitat loss and being extensively collected from the wild for horticulture and natural products. Cultural value is increasingly important in the effective conservation of biodiversity. The present study evaluated the biocultural value of the known uses of Aloe, excluding the domesticated and commercially cultivated A. vera. Over 1,400 use records representing 173 species were collated from the literature and through personal observation; this paper presents a synopsis of uses in each of 11 use categories. Medicinal uses of Aloe were described by 74% of the use records, followed by social and environmental uses (both 5%). Species yielding natural products, notably A. ferox and A. perryi, were most frequently cited in the literature. Consensus ratios indicate that the most valued uses of Aloe are in medicine and pest control against arthropods and other invertebrates.

Documented utility and biocultural value of Aloe L. (Asphodelaceae): a review.

Brummitt (2006) has identified the paraphyly-mono phyly controversy as the most important issue under debate in taxonomy today. In essence the argument is about the merits of the evolutionary (Darwinian) versus phylogenetic (cladistic/Hennigian) approaches towards plant classification. Brummitt's response is in support of the letter by Nordal & Stedje (2005) who pointed out, together with 148 co-signatories, that the rejection of paraphyletic groups as taxa in classification construction by the phylogenetic school is not only a logical impos sibility but is causing unnecessary chaos in plant tax onomy. As a field/herbarium taxonomist in the world's richest temperate flora, that of southern Africa, I can only but endorse this observation. To deny this fact, as some phylogeneticists tend to do (e.g., Dias & al., 2005), is to be out of touch with reality. With more than 20,000 plant species in South Africa alone, the practical value of classifications that are optimally stable, informative and predictive is of utmost importance to come to grips with such astounding diversity. Hence I would like to offer some observations in defense of paraphyletic groups from the perspective of an end-user of plant classifications. In this contribution I argue that practical considerations and the needs and expectations of society should provide the primary guidance in a debate that has hitherto focused mainly on academic issues. For the benefit of readers not familiar with the distinction between evolutionary and phylogenetic taxonomy (mainly espoused and debated in the zoological literature), concise information on the two approaches and its relevance to the current debate is provided. Since completion of the present contribution, the two approaches have also been discussed by H?randl (2007). Evolutionary and phylogenetic classification. ? Classification by its very meaning implies an ordering for practical purposes. It also implies the grouping of objects into classes based on shared characters (similarity). From its inception as folk taxonomies, plant classification has been an applied and practical activity. The success that Linnaeus' artificial sexual system enjoyed was largely due to its simplicity and practical advantages in identification. To address the needs of science, industry and broader society, taxonomists over the years have striven to produce general-purpose (multi-purpose) classification systems, not only by purely phenetic means (including taxomet rics), but since the inception of evolutionary theories increasingly by the use of the best available phylogenetic framework for incorporating attributes of plants from as many fields as possible. The aim is to construct evolu tionary classifications allowing us to store and retrieve information where it is known and predict its presence or absence where it is not. In this way plant taxonomy has not only fulfilled its essential role as an integrative and unifying discipline in botany, but has also enhanced the information storage and predictive value of classification systems. For practical plant identification and information storage and retrieval, the advantages of evolutionary clas sifications over phylogenetic ones (see below) are beyond question. Essentially evolutionary classification is based on the evolution of organisms, not just their phylogeny. Both the evolutionary classification and phylogenetic clas sification are genealogical, but the former is a genealogy of groups (classes) and the latter of clades. Mayr & Bock (2002) define evolutionary classification as 'a classifi cation that duly considers both evolutionary processes, the ecological adaptiveness of evolutionary divergence (degree of difference) and the genealogy (phylogeny) of the taxa.' Mayr & Bock refer to the phylogenetic approach as cladification (instead of classification) and define it as 'an ordering system in which branches of a cladogram, or parts of such branches, are arranged with reference to the sequence of the branching points in the cladogram and based on the principle of holophyly'?holophyly which refers to the cladists' definition of monophyly, namely 'pertaining to a branch of the phyletic tree (and the species on this branch) derived from a stem species (with the first apomorphy diagnostic of this branch) and all of its de scendants, no matter how different.' Inpractice, however, the two approaches have much in common, one of the main distinctions being recognition of paraphyletic taxa by evolutionary taxonomists (strictly speaking, paraphyly as a concept does not exist in an evolutionary classifica tion). The methodological differences between the two

Abraham E. Van Wyk

Papers

Evolutionary history and leaf succulence as explanations for medicinal use in aloes and the global popularity of Aloe vera

An inventory of Vhavenda useful plants

Trends in the evolution of dicotyledonous seeds based on character associations, with special reference to pachychalazy and recalcitrance

Documented utility and biocultural value of Aloe L. (Asphodelaceae): a review.

The end justifies the means