A NUMERICAL–TAXONOMIC STUDY OF THE GENUS BULNESIA (ZYGOPHYLLACEAE): CLUSTER ANALYSIS,ORDINATION AND SIMULATION OF EVOLUTIONARY TREES

Cluster analysis by four methods, ordination by principal component analysis (PCA) and simulation of evolutionary trees (Wagner Trees) were performed on morphological data from 43 characters of eight species of the South American genus Bulnesia (Zygophyllaceae). The results of cluster analysis and principal component analysis in general agree and show that there are three pairs of taxa that appear, or obviously are, closely related. These are the pairs B. arborea–B. carrapo, B. foliosa–B. schickendantzii and B. retama–B. chilensis. These methods also indicate that the southern species B. bonariensis occupies an intermediate position between the pair of northern tropical species (B. arborea, B. carrapo) and the remaining southern species. From the beginning it was assumed that these three multifoliolate species with large flowers may be rather primitive. The Prim network indicates that these three species are closely related among themselves. Also in two of the three Wagner Trees they are placed in a group. In all cases B. sarmientoi is shown as the more remote and isolated of all species. It is regarded as a unique, specialized arboreal species showing extreme reduction in number of leaflets and carpels, leaf and flower size, etc. All graphic representations (Fig. 1–3) show the phenetic similarity or the close phylogenetic relationships of the pairs B. foliosa–B. schickendantzii and B. retama–B. chilensis to each other. These four species would represent a rather advanced group. The most xerophytic species B. retama and B. chilensis are regarded as the most advanced taxa and the most specialized histophysiologically. These occupy extreme and distant positions in PCA diagrams and Prim network, and top positions in the Wagner Trees.     

Comparative morphometry as a diagnostic tool applied to species delimitation in the genus Gastridium P. Beauv. (Poaceae)

Based on critical examination of both fresh and dried specimens and a morphometric analysis of herbarium specimens we performed a comparative study of the three closely related Gastridium (Poaceae, Tribe: Poeae, Subtribe: Agrostidinae) species G. ventricosum, G. phleoides and G. scabrum collected in Italy. The study aimed to provide new diagnostic tools to improve the taxonomy of the genus and confirm species delimitation. Variation in floral morphology in the three species was explored using seven quantitative and ten qualitative characters measured on 318 spikelets, both awned and unawned. Statistical methods, including principal components analysis (PCA) and non‐metric multidimensional scaling (NMDS), were used. Numerical analyses showed a general distinctness of spikelets and florets, consistent with the three studied species, and revealed among and within species variation patterns in both spikelet types. Accordingly, the most informative quantitative characters appeared to be the width and length of glumes and the length of awns, useful to distinguish G. phleoides which has the narrowest glumes and longer awns than the other species, while G. scabrum has the widest glumes. The most informative qualitative characters appeared to be the presence/absence of thick hairs or minute tubercles on the upper side of the lemma. The autonomy of the three studied species was confirmed. The taxonomic significance of the results is briefly discussed, and notes on the species distribution are included. Some nomenclatural and taxonomic notes on G. scabrum, of which literature still showed evidence of a general unawareness, are provided.     

Molecular phylogeny of three groups of acacias (Acacia subgenus Phyllodineae) in arid Australia based on the internal and external transcribed spacer regions of nrDNA

The phylogeny of three groups of arid Australian acacias ‐ the Acacia victoriae, A. murrayana and A. pyrifolia groups ‐ was constructed based on parsimony analysis of sequence data from the internal and external transcribed spacers (ITS and ETS) of the nuclear ribosomal DNA. Forty ingroup taxa were sequenced, including multiple accessions for some taxa and two species (A platycarpa and A. longispinea) that had been identified in other analyses as relatives of these acacias. Acacia anthochaera was used as the functional outgroup.

The ITS and ETS regions proved to be sufficiently variable to resolve relationships at both the specific and intra‐specific level. Two main clades were resolved. One clade confirmed the monophyly of the Acacia murrayana group, and relationships of species were strongly supported. All taxa in this clade have a similar pattern of seedling leaf development. In the second clade, the A. pyrifolia group is nested within the A. victoriae group and all taxa have spinose stipules. Acacia platycarpa and A. longispinea are related to this clade. Phyllode nerve number (uninerved or plurinerved) proved to be homoplasious.

Acacia victoriae is a widespread and very variable species. The molecular data identified two major groups: a group of populations occurring across northern Australia and a group of populations from the Western, Central and Eastern deserts. Further analysis of population variation is required to assess the taxonomic status of various forms in this species complex.

The geographic distributions of sister taxa suggest predominantly allopatric speciation. The degree of molecular divergence and position of the clades within subgenus Phyllodineae suggest that the lineages are not of recent origin, but have a history that relates to increased aridity in the Australian Eremean region during the Cenozoic.     

BIOLOGICAL AND HISTORICAL FACTORS INFLUENCING GENETIC DIVERSITY IN THE SCUTELLARIA ANGUSTIFOLIA COMPLEX (LABIATAE)

Studies of genetic diversity at isozyme loci were used to examine the phylogenetic distribution of several frequently reported population-genetic parameters in a putatively monophyletic group of plant species, the Scutellaria angustifolia complex. The influence of taxon-specific differences in habitat preference, breeding system, degree of endemism, and phylogenetic relatedness was examined. Many characters of reproductive morphology traditionally used in phylogenetic inference vary with breeding system. To the extent that reproductive systems are conservative markers of phylogenetic relationships, one would expect the distribution of genetic variation to be similar in closely related taxa. Results showed that closely related taxa may exhibit very different genetic-diversity statistics and that distantly related taxa may exhibit very similar genetic-diversity statistics. This suggests that complex patterns of evolution of breeding systems and morphological characters have occurred in the ten taxa included in the Scutellaria angustifolia complex. Similarity in habitat is not associated with similarity in genetic diversity in this group of species.     

Allium purpureoviride sp. nov. (Alliaceae) from east Anatolia,Turkey

Allium purpureoviride M. Koyuncu & ?. Genç (sect. Melanocrommyum) is described as a new species from east Anatolia, Turkey. The new species is closely related to A. rothii Zucc. from Israel and some characters of the new taxon show similarity with A. cyrilli Ten. and A. asclepiadeum Bornm. The morphological characters of the related taxa are discussed and the distribution of the taxa is mapped. The diploid chromosome number is 2n = 16.     

Morphometrical analyses of Secale (Triticeae, Poaceae)

Some fifteen taxa ranked as species or subspecies have generally been recognized within Secale. However, most of these seem impossible to separate on morphology alone. Based on 14 morphological characters considered of diagnostic value and scored on 44 specimens representing most of the taxa a Principal Components Analysis (PCA) was carried out. Limited correlation was found between the characters and consequently the first three principal axes account for only about 60% of the total variation. The PCA shows only a weak separation of annual and perennial taxa. Further analyses mainly of spikelet characters support merging of most of the previously accepted taxa within each of these two groups. A total of three species with five infraspecific taxa are here proposed within the genus and a key is provided to the taxa.     

A proposed reclassification of Bryum,Anomobryum and Brachymenium (Musci,Bryaceae)

Abstract

The traditional generic classification in the Bryoideae (Bryaceae) is based primarily on details of the sporophyte, particularly peristome reduction and capsule inclination. Recent research, however, has suggested that closely related species in Anomobryum can have very distinct capsules, varying from complete peristomes and inclined capsules to reduced peristomes and erect capsules. The suggestion is made here that sporophyte features, especially those related to peristome features, may obscure phylogenetic relationships. A revised classification is proposed, based on analyses of 100 species of Bryum, Anomobryum, and Brachymenium and sixteen sporophytic and gametophytic characters. The revised classification groups species with similar gametophores but is supported by at least some sporophytic characters. Analysis of variance and principal components analysis indicate that both the traditional and revised classification provide effective summaries of the variation within the 100 species examined. The new classification consists of three informal groups of species which can be recognized at generic rank. One comprises Bryum species, including those with reduced peristomes and inclined capsules. A second comprises all species of Anomobryum, as well as species of Bryum and Brachymenium with similar gametophores. The third group consists of the rosulate species of Bryum and Brachymenium. Phylogenetically, the second group may be more closely related to Pohlia than to the species in the first and third groups. The third group appears to be most closely related to Rhodobryum and Plagiomnium. Suggested names are provided for groups one and three, while the name Bryum is retained for group two. No nomenclatural changes are made, however, until more research is done.     

Morphometric analysis of varieties of Acacia caven: (Leguminosae, Mimosoideae): Taxonomic inferences in the context of other Argentinean species

The aims of this study were to evaluate the degree of morphological differentiation between six varieties of Acacia caven and to examine their taxonomic validity in the context of other Argentinean species of the genus. To accomplish these purposes, morphological traits have been analyzed using multivariate methods (non parametric ANOVA, phenetic analysis and principal component analysis) on the varieties of A. caven and other six species of the genus, represented in Argentina. The phenogram obtained showed two principal clusters, one grouping all the species of subg. Acacia and the other grouping the species of subg. Aculeiferum. This result agreed with Vassal's infrageneric classification. However, the results of the principal PCA gathered the seven species here included in three groups, which were consistent with Bentham's infrageneric treatment. The ANOVA method indicated that most of the morphometric characters used were statistically sound for differentiation between varieties of A. caven. Further studies, including more species and characters, must be performed in order to clarify the position of Acacia boliviana and the relationships between A. caven and A. curvifructa.     

Morphologic comparisons of hatchery-reared specimens of Scaphirhynchus albus, Scaphirhynchus platorynchus, and S. albus × S. platorynchus hybrids (Acipenseriformes: Acipenseridae)

Extensive habitat modifications within the Mississippi and Missouri rivers have presumably interfered with the reproductive isolating mechanisms between the endangered pallid sturgeon, Scaphirhynchus albus, and the sympatric shovelnose sturgeon, Scaphirhynchus platorynchus, causing hybridization between these two species. Several character indices were developed to assist fisheries biologists in identifying specimens of S. albus, S. platorynchus, and their putative hybrids. The indices have numerous assumptions, including that pure strains of both parental species are within the sample analyzed and that hybrids are morphologically intermediate relative to their parents. If these indices have produced inaccurate identifications, then previous work on Scaphirhynchus studies in the Mississippi and Missouri rivers are questionable, including status surveys, captive propagation efforts, or the harvesting of tissues for genetic studies. In this study we tested indices by examining progeny of ‘known’ pallid, shovelnose, and hybrid sturgeon propagated, raised, and preserved at hatcheries. These 60 specimens [78–600 mm standard length (SL)] were propagated with breeding stock from the upper Missouri River drainage, where hybridization between these two species presumably does not occur. Existing indices did not correctly identify small (<250 mm SL) or a combination of small and large (>250 mm SL) sizes of S. albus, S. platorynchus, and their hybrids. Indices worked fairly well in identifying large S. platorynchus, but not in differentiating large S. albus from hybrids. We used principal components analysis (PCA) as an alternative approach to character indices. No a priori knowledge of the identity of the specimen is required with this multivariate technique, which avoids potential circular reasoning present in indices. We were able to completely or almost completely separate both sturgeon species and their hybrids by extracting principal components from a correlation matrix of 13 meristic characters in a standard PCA and extracting size‐corrected principal components from a covariance matrix of 51 morphometric variables using a sheared PCA. Additionally, we demonstrated that first generation hybrids were intermediate with respect to their parental species. Multivariate analyses with a reduced character set of six meristic and 12 morphometric variables also led to accurate and reliable specimen identification. Head spines and numerous qualitative characters are also extremely useful in differentiating between Scaphirhynchus species and their hybrids. In addition to all morphometric characters, some meristic characters and the degree of head spine fusion vary significantly with SL of sturgeons. Recording appropriate data from released specimens, including photovouchers, and making this information available is essential for researchers to have any scientific or legal basis for genetic or any other studies involving these sturgeons.     

瑞香属和荛花属的数量分类研究

瑞香属和荛花属为瑞香科瑞香亚科的落叶或常绿灌木,中国西南部是瑞香属和荛花属的重要分化中心。全世界共有瑞香属95种、荛花属70种,中国分布有瑞香属52种、荛花属49种。瑞香属和荛花属的分类学研究一直存在不同程度的分歧。花盘形状和果实类型在传统分类中一直是区分瑞香属和荛花属的典型特征,而花盘形态和果实类型在2个属中存在交叉和过渡,部分植物分类学家根据这些特征将两个属进行过不同程度的归并。该研究采用数量分类法对瑞香属77种(变种)和荛花属62种(变种)植物,选取32个形态学性状进行聚类分析和主成分分析。结果表明:聚类分析和主成分分析均显示两属均未形成单系类群。在主成分分析中,前3个主成分分析的贡献值为35.56%,传统分类中用来区分两属的花盘形状、叶序及果实类型等特征对前3个主成分贡献相对较小,因此,传统分类学中对这两个属进行区分的性状并没有典型的分类学意义。同时,聚类图和主成分分析得到的散点图均不能将这两个属区分开来。数量分类研究结果显示两属植物存在明显的交叉,支持瑞香属和荛花属不是两个独立自然类群的观点。     

A phenetic analysis on the genus Lolium (Poaceae) in Iran

In this study, 68 specimens of the genus Lolium were scored for 27 characters, comprising 12 vegetative, 12 inflorescence and 3 seed characters. The aim of the study was to investigate the species relationships within the genus in Iran. The data were analysed using principal components analysis (PCA) and cluster analysis. Both analyses separated L. perenne, L. persicum, L. temulentum, L. multiflorum from each other. According to previous authors, L. rigidum and L. loliaceum show little difference from each other and are not separable to a species level. In this study these two species separated clearly from the other species, but were most closely related to L. perenne following cluster analysis and to L. multiflorum following PCA. L. persicum was found to be the most distinct species within the genus Lolium in Iran.     

Phylogenetic relationships between two rare acacias and their common, widespread relatives in south-western Australia

Knowledge of phylogenetic relationships betweentaxa is particularly valuable for conservationmanagement of threatened taxa in anevolutionarily diverse flora such as that foundin the south-west of Western Australia. Acacia sciophanes and A. lobulata aretwo threatened species that have restricteddistributions at the edge of the range of theirwidespread relatives, A. anfractuosa andA. verricula respectively. The phylogenyof these species pairs was investigated usingRFLP analysis of cpDNA. Both restricted specieswere shown to be phylogenetically distinct.Acacia sciophanes and A. anfractuosaare sister species and display the characteristics of a relatively recent evolutionary lineage. In comparison A. lobulata shows significant divergence from A. verricula and is not closely related to the species group in which A. verricula is placed. Acacia lobulataappears to represent an ancient lineage and ismost likely a relictual species. Acaciaverricula also has characteristics of a moreancient evolutionary lineage than A.sciophanes and A. anfractuosa. Ifpriority setting processes based onphylogenetic principles were to be applied tothese species A. lobulata would have thegreater biodiversity value for conservationmanagement.     

CHROMOSOME NUMBERS IN THE LEGUMINOSAE. III. SPECIES OF THE SOUTHWESTERN UNITED STATES AND MEXICO

Turner, B. L., and Olin S. Fearing. (U. Texas, Austin.) Chromosome numbers in the Leguminosae. III. Species of the Southwestern United States and Mexico. Amer. Jour. Bot. 47(7) : 603–608. Illus. 1960.—Chromosome counts for 43 species of the Leguminosae from the southwestern United States and Mexico have been reported. These include first reports for 42 taxa of which 16 are for the subfamily Mimosoideae. Olneya tesota (2n = 18) is the only new generic count listed. Chromosome reports of particular significance include a single polyploid count for a North American species of Acacia, as well as diploid and tetraploid counts for closely related taxa in this genus. Four species of the genus Schrankia were found to be diploid with In = 26, indicating a base of x = 13 instead of the x = 8 reported by some previous workers. Leucaena pulverulenta was found to have a diploid count of 2n = 56 indicating a base of x = 14.     

The systematics of Australian Daphnia (Cladocera: Daphniidae). Multivariate morphometrics

Forty nine characters were measured in each of 76 male and 200 female Daphnia including specimens from all eleven taxa described from the genus in Australia, except D. jollyi. Separate multivariate analyses (cluster, principal components and discriminant) of males and females each revealed only five morphological groups in the genus corresponding to the species D. occidentalis, D. lumholtzi, D. cephalata, D. nivalis, and a conglomerate of all other taxa described from the D. carinata complex, D. carinata (sensu lato). Interpretation of the male results was straightforward, but that for females was not because of the occurrence of an environmentally induced seasonal change in morphology (cyclomorphosis) in females. Log transformations of the female data successfully isolated the effects of cyclomorphosis. The seasonal morphs formed two groups which were further differentiated into taxonomic groups.     

A multivariate morphological analysis of the Cardamine concatenata alliance (Brassicaceae)

Principal coordinate analysis using Gower’s similarity coefficient and canonical discriminant analysis were performed using morphological data to assess species distinctness in theCardamine concatenata alliance, comprising the eastern North American dentarias. The results of an overall principal coordinate analysis of the alliance using quantitative and qualitative characters revealed distinct and separate clusters that correspond to five previously recognized species (C. angustata, C. concatenata, C. diphylla, C. dissecta, C. maxima). One additional taxon,C. incisa, was found to group closely with theC. diphylla cluster. In a second principal coordinate analysis including only individuals fromC. diphylla andC. incisa, both are supported as distinct morphological entities. Canonical discriminant analysis of only above-ground quantitative characters was less effective in distinguishing previously recognized taxa, in keeping with the emphasis on qualitative characters in previous taxonomic treatments of the group.Cardamine incisa (Eames) Schumann (pro hybr.) is raised to the rank of species. A key to the species of theCardamine concatenata alliance is provided.