Search

Sedum plumbizincicola X.H. Guo et S.B. Zhou ex L.H. Wu (Crassulaceae), a new species restricted to lead-zinc mining areas in Zhejiang Province, China, is described and illustrated. This taxon belongs to sect. Sedum (H. Ohba) S.H. Fu based on the adaxially gibbous carpels and follicles. It superficially resembles S. alfredii Hance and three other Sedum species found in the same area, but differs from these other taxa in bearing 4-merous flowers. Differences in geographical distribution, growth habit, phenology, macromorphology, leaf and stem anatomy, as well as seed micromorphology among S. plumbizincicola, S. alfredii and other related taxa in the genus Sedum are also reported. nrDNA internal transcribed spacers (ITS) sequences from seven populations of S. plumbizincicola support the recognition of this as a taxonomic entity distinct from S. alfredii. [ABSTRACT FROM AUTHOR]

Macrofossils of Carpinus have been widely reported from the Cenozoic of the Northern Hemisphere. However, the leaf cuticules of the genus have rarely been described. A new species, named Carpinus tengchongensis Dai et B.N. Sun, sp. nov., is identified based on 13 leaf fossils, collected from the late Pliocene Mangbang Formation, Tengchong County of Yunnan Province, China. The important characters of the fossil are its oblong-ovate leaf shape, obliquely cordate base, doubly serrulate margin, straight and moderately thick primary vein, pinnate secondary veins, percurrent tertiary veins, orthogonally reticulate areoles, absence of veinlets, anomocytic stomata with double-layered stomatal rim, well-formed T-pieces and trichome bases, which indicates an affinity within the genus Carpinus section Carpinus subsection Monbeigianae, especially with C. tsaiana. Carpinus fossils were present from the Eocene to Pliocene with disjunctive distribution in the North Temperate Zone, which broadly reflected the present distribution pattern and probably demonstrates the tolerance of Carpinus to environmental change. [ABSTRACT FROM AUTHOR]

This study examined the detailed pollen morphological structures of sixteen Hypericum taxa (four endemic, twelve non endemic) including eight sections showing the natural distribution in Turkey: H. sect. Ascyreia ( H. calycinum L.), H. sect. Heterophyllum ( H. heterophyllum Vent.), H. Sect. Taeniocarpium ( Hypericum confertum Choisy subsp. confertum, H. venustum Fenzl , H. linaroides Bosse), H. sect. Drosocarpium ( H. montbretii Spach, H. bithynicum Boiss.), H. sect. Crossophyllum ( H. adenotrichum Spach, H. orientale L.), H. sect. Olympia ( H. olympicum L. subsp. olympicum), H. sect. Origanifolia ( H. origanifolium Willd., H. avicularifolium Jaub and Spach subsp. depilatum (Freyn and Bornm.) Robson var. depilatum, H. avicularifolium Jaub. and Spach subsp. byzantinum) and H. sect. Hypericum ( H. tetrapterum Fries, H. perforatum L., H. triquetrifolium Tura). These taxa were studied under light microscope and scanning electron microscope for the first time. Of the taxa studied, H. tetrapterum has the smallest pollen grains (on average 15.85-17.20 × 15.45-16.05 μm); and H. olympicum subsp. olympicum the largest grains (on average 22.90-23.10 × 21.40-22.10 μm). The pollen grains of 15 taxa are subprolate and one taxon is prolate-spheroidal. The regular pollen grains of all 16 taxa are 3-zonocolporate. Ornamentation is microreticulate; lumina regularly spaced in eight taxa, tectum perforatum; tectal perforations regularly spaced in seven taxa and tectum perforatum; and tectal perforations grouped together in one taxon. Endoaperture is cruciform porus, with short lateral and meridional extensions in ten taxa, cruciform porus, transversally elongated, with very small lateral extensions in one taxon and lalongate colpus in five taxa. Basic pollen types are ten taxa in type X, five taxa in type IV and one taxon in type II. [ABSTRACT FROM AUTHOR]

The main aim of the present study was testing the value of the morphological and anatomical characteristics of the needles in distinguishing Cedrus atlantica, C. libani and C. brevifolia. Nine populations were sampled in their natural habit and 25 characters were used to describe the variation of the brachyblast needles and to analyze the differences between species. The results indicated that morphological and anatomical needle characters provide valuable tools in discrimination of the taxa. The scored differences were statistically significant, as revealed in the Tukey's t test, discrimination analysis and hierarchical analysis of variation. The results support treating C. libani, C. atlantica and C. brevifolia as independent species. [ABSTRACT FROM AUTHOR]

Despite their genetic homogeneity, many taxonomic species are described as European dogroses ( Rosa L. section Caninae (DC.) Ser.) with consistent morphological variability. Here we report a morphometric study of 27 hip and leaf characters of proximate dogrose populations that include Rosa agrestis, a member of the subsection Rubigineae, in Flanders. In principal components analysis one R. agrestis population in Kanne had intermediate morphology between R. canina and R. corymbifera, on the one hand, and three other R. agrestis populations, on the other, suggesting hybridogenic origin. Half-sib R. agrestis seedlings were grown under controlled conditions and their leaf characters were studied. A tendency toward deviating morphology in seedlings from the Kanne population, analogous to the mother plants in the field, and a correlation for specific leaf characters between mother plants and their corresponding seedlings reinforce a genetic basis for the observed divergence in the Kanne population. The assumed hybridogenic mother plants did not produce fewer seeds per hip than the others of the pure populations. In addition, for all sampled dogroses, which included six species, the diameter of the discus was correlated with the number of seeds per hip, whereas the diameter of the orifice was not correlated with this character. This implies that only the diameter of the orifice and not the diameter of the discus might be decisive for species identification among European dogroses. [ABSTRACT FROM AUTHOR]

Clematis s.l. (including Archiclematis and Naravelia) is a genus of approximately 300 species with cosmopolitan distribution. The diversity of its pollen was surveyed in 162 taxa belonging to all infrageneric groups of Clematis s.l. Pollen morphology was investigated by use of scanning electron microscopy to identify useful characters, test taxonomic and systematic hypotheses, and elucidate pollen character evolution on the basis of the molecular phylogeny. Clematis pollen is small to medium (14.8-32.1 μm × 14.2-28.7 μm), oblate to prolate ( P/ E = 0.9-1.4) in shape. The apertures may be tricolpate and pantoporate sometimes with 4-zonocolpate and pantocolpate pollen grains as transitional forms. The tricolpate pollen grains are predominant and occur in all the sections of the genus, whereas pantoporate pollen grains can be found in sect. Tubulosae, sect. Viorna, sect. Viticella, and Naravelia only. Phylogenetic mapping of aperture types reveals that the pantoporate pollen type may be the apomorphy in the genus and evolved several times. The surface ornamentation in all taxa studied is similar and characterized by microechinae evenly distributed on the microperforate tectum. The size and density of spinules on the tectum vary greatly but successive in the whole genus. According to the character syndromes of the ornamentation, separating sect. Brachiata from sect. Meclatis is supported. Though pollen morphology may contribute to investigation of problematic taxa, the taxonomic value of pollen morphology is limited at the species level. [ABSTRACT FROM AUTHOR]

Molecular characterization of Tulipa L. species can elucidate the relationships among the species and provide more information about the taxonomy of this valuable genus. In this study, the genetic relationship among 39 Tulipa accessions from Khorassan and Yazd Provinces, located in east and northeast Iran, were analyzed using inter-simple sequence repeat (ISSR) primers. Ten selected ISSR primers from 20 screened primers generated a total of 97 polymorphic DNA bands. Unweighted pair-group method of cluster analysis based on Dice similarity values separated the accessions into nine groups. Seven species were recognized within these groups, and T. micheliana Hoog was the most frequently encountered species. The subgroups formed within both T. micheliana and T. lehmanniana Merckl. revealed a low level of diversity within these species. T. biebersteiniana Schultes & Schultes fil. and T. biflora Pallas accessions made a separate clusters. The grouping of accessions was generally consistent with principal coordinate analysis (PCA) and clearly showed the position of species in the subgenera and sections of Tulipa. These results clearly showed the usefulness of DNA fingerprinting for identification of Tulipa accessions, and it is imperative to collect and characterize more genetic variability from the other distribution areas of this genus. [ABSTRACT FROM AUTHOR]

Nuclear genome size was determined to investigate the relationships between all 19 species of Araucaria de Jussieu. Species from the two other genera of Araucariaceae, Wollemia and Agathis, were also studied. The genome size of 17 out of the 19 species of Araucaria are reported here for the first time. All Araucariaceae have the same chromosome number 2 n = 26. However, the nuclear DNA contents (2C value) for Araucaria range from 31.3 to 45.4 pg. There is a good correlation between genome size and division in sections, and geographical distribution. The two species from South America have 44.7 and 45.4 pg, the two species from Australia have 35.7 and 44.4 pg and the two species from New Guinea 34.7 and 40.4 pg. All 13 species of New Caledonia and the one from Norfolk Island have a similar, if not identical, amount of nuclear DNA of, on average, 31.9 pg. This corroborates the identical DNA rbcL sequences found for the New Caledonian araucarias. It suggests that the species from New Caledonia diversified more recently and it questions their status as separate species . Compared with this 31.9 pg a strong increase seems to have occurred in the genome size of the 'mainland' araucarias. Genome sizes are evaluated and compared with available taxonomic treatments and extant geographic spreading. The nuclear DNA contents found within the sections are close, making it possible to assign an unknown plant to a section. A difference of 1 pg, which amounts to a difference of 978 Mbp, far exceeds a single character. Nuclear DNA content, as measured by flow cytometry, may conveniently be used to produce systematic data . It is applicable even with young plants or seeds for monitoring the trade in endangered species. [ABSTRACT FROM AUTHOR]

The origin and evolution of angiosperms can be unravelled by using fossil records to determine first occurrences and phytogeographic histories of plant families and genera. Many angiosperm families, for example the Onagraceae, have a poor macrofossil record, but are more common in palynological records. Modern Onagraceae produce pollen clearly distinct from that of other angiosperms. Combined morphological features obtained by use of light and scanning electron microscopy have enabled assignment of fossil Onagraceae pollen to extant genera, and therefore tracing of the origin and past distributions of extant Onagraceae lineages. We studied a Miocene palynoflora from the Daotaiqiao Formation of north-east China. Using the single-grain technique, we examined individual Onagraceae pollen/tetrads using both light and scanning electron microscopy. Fossil Onagraceae pollen is more frequent than macrofossil remains, but is still rare, and usually represented by a single taxon in palynological samples. Remarkably, samples from the Miocene of north-east China contain five different species: two of Circaea, one of Epilobium, and two of Ludwigia. Such a large number of Onagraceae taxa from a single palynoflora is unknown elsewhere. Whereas Ludwigia pollen is known from Cenozoic sediments of the northern hemisphere, the Circaea pollen is the first fossil pollen assignable to this extant genus. This is also the first fossil record of Epilobium from China. Although the young geological age of this sample does not enable consideration of time of origin for the genera encountered, the co-occurrence of Circaea, Epilobium, and Ludwigia in the mid to late-Miocene of East Asia sheds some light on their phytogeographic histories. [ABSTRACT FROM AUTHOR]

Calypogeia sphagnicola is one of nine species of the genus Calypogeia known in Europe. Occurrence of the species is closely connected with peat bogs. Nowadays, two forms of this species are distinguished- C. sphagnicola f. sphagnicola and C. sphagnicola f. paludosa. The results of the present study, based on two classes of markers-isozymes and sequences of chloroplast genom ( trnH- psbA, rpoC1)-unanimously support the genetic differentiation within the taxon and show that the present-day forms represent genetically distinct species. Phylogenetic analysis resolved two lineages that correspond with the present-day forms with high bootstrap support, which differ in ploidy level: C. sphagnicola f. sphagnicola is haploid, whereas C. sphagnicola f. paludosa is a diploid form. Allopolyploid origin of the diploid form was revealed by the isozyme pattern. Nei's genetic distance between the two present-day forms of C. sphagnicola was 0.472. The forms in Poland have an allopatric pattern of geographic distribution: C. sphagnicola f. sphagnicola occurs exclusively in the lowlands of the northern part of the country on raised peat bogs, whereas C. sphagnicola f. paludosa is found only in the mountains of southern Poland, mainly in the subalpine zone, where it grows on Sphagnum- Polytrichum hummocks on the upper part of north-facing slopes. Plants regarded in this study as C. sphagnicola f. sphagnicola morphologically correspond to the syntype specimen of C. sphagnicola. [ABSTRACT FROM AUTHOR]

Cuscuta (dodder, Convolvulaceae) is a genus of about 200 species of obligate stem parasites with subcosmopolitan distribution. The diversity of pollen and ovule production was surveyed in 128 species and ten varieties. Taxa were assigned to Cruden's mating system categories based on their pollen-ovule ratios. Variation and correlations among floral characters were analyzed using regression and ANOVA, while the mating system categories were subjected to a linear discriminant and canonical variates analysis to assess their cohesiveness. Our data strongly suggest that most Cuscuta species possess a wide range of mixed-mating systems. Whereas four ovules develop in each flower, pollen production varies over three orders of magnitude. Several Cuscuta taxa are highly outcrossing, but no species could be identified that are exclusively selfing. The transition from the one-style flowers of subg. Monogynella to the two-style flowers of subgenera Cuscuta and Grammica, and from simultaneous to sequential maturation of the two stigmas in the latter subgenus, has decreased the role of herkogamy as a facilitator of outcrossing. These evolutionary changes are associated with an increase of species richness in subgenus Cuscuta, and especially in subgenus Grammica. Morphological features were not individually found to have a strong correlation to the mating system, but in general, larger corollas and stigmas were associated with greater pollen-ovule ratios. Cuscuta presents some puzzling results when considered in light of the sex allocation theory, as only some infrageneric lineages demonstrate the predicted pollen size-number tradeoff, while Cuscuta gracillima complex (in subgenus Grammica) displays an unexpected negative relationship between pollen size and style length. The relationship between host range and mating system is discussed, prompting further research into the co-evolution of pollination systems and life history traits between parasites and their host species. [ABSTRACT FROM AUTHOR]

The tribe Stipeae with an estimated number of ca. 600 species is part of the grass subfamily Pooideae and has near worldwide distribution. Its species are often dominant constituents of steppe vegetation and other grasslands, especially in Eurasia, the Americas and Australia. The taxonomy of Old World Stipeae has been studied to date primarily on the basis of morphology and anatomy, while existing molecular phylogenetic investigations have mainly dealt with New World or Australian taxa. We studied 109 new ingroup taxa with a focus on Old World Stipeae (in addition with an extensive outgroup sampling) using chloroplast and nuclear ribosomal DNA sequences (3′ trnK region, ITS1-5.8S gene-ITS2), and discuss taxonomic key characters. Five highly supported monophyletic lineages were identified, some of which were rather unexpected: (a) the narrowly defined Stipa core clade, which is primarily Eurasian but extends into Africa north of the Sahara Desert, (b) the majority of Old World Piptatherum, (c) a 'Transcontinental Stipeae Clade' encompassing Eurasian, African, American and Australian lineages, (d) a Himalayan to E Asian clade and (e) the single species Achnatherum splendens. The large 'Transcontinental Stipeae Clade' contained several lineages of Eurasian Stipeae different from the Stipa core (a), i.e., genera Aristella, Celtica, Oloptum gen. nov., Stipella stat. et. gen. nov., species of Achnatherum, and the species-rich lineages of Nassella/ Jarava in America and of Austrostipa in Australia. In our circumscription Ptilagrostis was nested in (d), a clade (which included some species of Achnatherum and poorly studied Himalayan species ascribed to either Stipa or Orthoraphium) and whose internal structure remained unclear. Oloptum, gen. nov., is described, and the following combinations are made: Achnatherum pelliotii, comb. nov., Aristella keniensis, comb. nov., Oloptum miliaceum, comb. nov., Stipella, stat. et. gen. nov., S. capensis, comb. nov., S. nitens, comb. nov., S. parviflora, comb. nov., S. staintonii, comb. nov., and S. tigrensis, comb. nov. [ABSTRACT FROM AUTHOR]

The botanical survey of Wadi Wateer, located in the southeastern Sinai, revealed the presence of a plant that provides an important new record to the Flora of Egypt: Cocculus hirsutus (L.) Theob. This plant has not been recorded previously as existing in its wild form in the Flora of Egypt. The plant cover in Wadi Wateer is dominated by plant taxa belonging to the Saharo-Sindian phytogeographical element. However, many plants in the wadi have been attributed to the Sudanian chorotype, such as Acacia tortilis (Forssk.) Hayne subsp. raddiana (Savi) Brenan, Chrozophora brocchiana Vis., Lycium shawii Roem & Schult., Moricandia sinaica (Boiss.) Boiss., Cocculus hirsutus (L.) Theob. and Cocculus pendulus (J.R. & G. Forst.) Diels. The presence of Sudanian chorotype plant taxa [including the newly recorded Cocculus hirsutus (L.) Theob.] provides evidence that Wadi Wateer and Aqaba Gulf functioned as migratory tracks for these African plants, assisting their penetration into the Saharo-Sindian, Mediterranean and Irano-Turanian phytogeographical regions in the Sinai and Asia. This study suggests that Wadi Wateer should be declared a protected area for its habitat and climatic diversity as well as for its phytogeographical significance. [ABSTRACT FROM AUTHOR]

The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18-19 million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10 million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today's species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.). [ABSTRACT FROM AUTHOR]

Comparison of leaf morphometric variation and phylogenetic analyses based on nrITS and partial trnC-D cpDNA sequences were conducted for samples of Lysionotus pauciflorus sensu lato collected from China, Japan and Taiwan. In the morphometric comparison, leaves of plants from Japan proper and those from Taiwan proper were not significantly distinguishable by their leaf length to width ratio. In phylogenetic analyses, monophyly of L. pauciflorus s. l. samples was strongly supported, and Japanese and Taiwanese samples fell into a clade separate from Chinese samples. In the Japan-Taiwan clade, plants from Japan proper formed a sister clade to those from Okinawa Island (Japan) and Taiwan. The present results suggest that (1) the L. pauciflorus s. l. samples from China, Japan and Taiwan must be treated as a single species; (2) L. pauciflorus s. l. originated in China; (3) a single dispersal event, dispersal via a land-bridge during low sea levels in a Pleistocene glacial maximum, from China to Taiwan and Japan is proposed; (4) three oversea dispersal events, probably through anemochory, to Japan proper, across the Tokara Gap, to Okinawa islands crossing the Kerama Gap, and from Taiwan to Lanyu Island are proposed. The study gives further insight into the biogeographical dynamics between the Ryukyus and surrounding areas. [ABSTRACT FROM AUTHOR]

The first fossil record of the genus Nageia Gaertner from the Tertiary of southern China is reported. Nageia hainanensis sp. nov. is described from the Eocene Changchang Formation of Hainan Island. The extant species of Nageia are widely distributed in southeastern Asia, from northeastern India to southeastern China and southern Japan, and southward through Indochina to the Malay Archipelago and New Guinea. The fossil evidence of Nageia has been discovered from the Lower Cretaceous of the Far East of Russia and Japan. The distribution of both modern and fossil species of Nageia indicates that this genus could have originated in the northeastern part of Asia in the Early Cretaceous and spread to south China at least in the Eocene. Discovery of Nageia fossil record in south China provides important evidence for the geological and phytogeographic history of the genus. [ABSTRACT FROM AUTHOR]

The genus Dipteronia Oliv. endemic to central and southern China consists of two species, D. sinensis Oliv. and D. dyerana Henry, both of them are rare and endangered. In the present study, genetic variation in 17 populations of D. sinensis and four populations of D. dyerana was estimated using ten polymorphic chloroplast microsatellite loci (cpSSR). Forty-nine chloroplast haplotypes were identified from 204 individuals analyzed. Thirty-nine haplotypes were found in D. sinensis, while ten in D. dyerana. No haplotype was shared between the species. AMOVA analysis revealed that the majority of the genetic variation was partitioned among populations within D. sinensis ( F ST = 0.7980) and D. dyerana ( F ST = 0.654). Cluster analysis grouped the 21 populations into two groups according to their species delimitation. The populations of D. sinensis were further divided into two subgroups corresponding to their geographical distributions. Correlation analysis revealed significant correlation between geographical distance and genetic distance of these populations ( r = 0.326, p < 0.01 for D. sinensis vs. r = 0.777, p < 0.05 for D. dyerana). Genetic structure of these populations and a calculated pollen-to-seed flow ratio of (3.2:1 vs. 0.6:1) within the species suggested that little gene flow has occurred among the populations over an extended period. Thus, it implies that the genus Dipteronia might have experienced a genetic bottleneck and limited expansion during its evolutionary history. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships within the genus Pieris (Ericaceae) were investigated based on the rbcL and matK genes along with five spacer sequences of chloroplast DNA to address questions regarding the phylogeography of the genus in association with insular plants on the Ryukyu Islands. The most parsimonious trees indicated that P. floribunda from eastern North America is a sister taxon to the remaining taxa examined, and suggested that the East Asian taxa examined are monophyletic. A morphologically cohesive group, section Pieris, was revealed to be paraphyletic. Within the East Asian clade, insular endemics from the Ryukyu Islands, Taiwan, and mainland Japan formed a sister group to P. formosa from the Himalayas and southern China. Our data suggest that the insular endemics of the Ryukyu Islands and Taiwan arose via allopatric divergence as a result of a paleogeographical land configuration of a landbridge during the early–middle Pleistocene in the Quaternary Period. [ABSTRACT FROM AUTHOR]

A molecular study of the wetland pleurocarpous moss Hamatocaulis vernicosus (Mitt.) Hedenäs, based on the ITS region, the trnL- trnF region, and rpl16 revealed two cryptic species. One of these is widespread in Europe, and was also sampled from several localities in Minnesota (United States). The other cryptic species occurs only south of the boreal zone in Europe, and was in addition sampled from single localities in Peru and northernmost Asiatic Russian Federation. Although it seems likely that the southern species colonized parts of Europe from southern refugia after the last glaciation, its wide distribution outside Europe indicates that the speciation event is unrelated to the European glacial history. No correlations could be found between variation in habitat preferences (pH and electric conductivity) and molecular variation. [ABSTRACT FROM AUTHOR]

Floral isolation has been considered to be an important reproductive mechanism governing the species diversification in many genera. In a classic example Aquilegia, sympatric species from North America with diverse floral traits are generally associated with specialized pollinators that prohibit interspecific hybridization. It remains unclear whether species diversification in the genus from Eurasia is also maintained by floral isolation. We investigated floral phenology, floral characteristics and pollinators in three sympatric Aquilegia species ( A. ecalcarata, A. incurvata and A. yabeana) in the Qinling Mountains, Shanxi Province, China from 2001 to 2005. The spurless A. ecalcarata flowers earlier than the other two species with nectar spurs but their floral phenology overlaps. Major pollinators of A. ecalcarata are syrphid flies while bumblebees are major for A. incurvata and A. yabeana. Therefore our observations confirm that mechanical isolation through differential pollinators could contribute reproductive isolation between spurless and spurred species, as demonstrated by studies from North America. Whether floral isolation plays a major role in the reproductive isolation between two spurred species ( A. incurvata and A. yabeana), however, remains to be seen. Further studies are required to quantify the potential role of geographical isolation because they occupy different habitats. [ABSTRACT FROM AUTHOR]

Hybridization and polyploidization are important evolutionary processes in higher plants and have greatly enriched the diversity of the genus Potamogeton (Potamogetonaceae). To study the phylogenetic relationships and hybrid origin of Potamogeton species, 35 accessions representing 20 species, including diploids, tetraploids and hexaploids, and three hybrids were collected in China and their ribosomal internal transcribed spacers (ITS) were cloned, sequenced and statistically analyzed. The data showed that ITS sequences were informative to analyze the phylogeny of Potamogeton, and the phylogenetic tree revealed that Potamogeton species examined could be mainly divided into two groups (Group I and II), corresponding to subgenus Potamogeton and subgenus Coleogeton, respectively. Then, the evolutionary mechanism on the polyploidy of Potamogeton species was discussed. P. natans probably was an allotetraploid and one of its parent might result from aneuploidy change of species with 2n=28. P. hubeiensis might be derived from the hybridization between P. octandrus and P. cristatus. We suggested that both P. lucens and P. maackianus probably were allotetraploids, and P. obtusifolius might be a diploid hybrid between P. compressus and P. pusillus. Moreover, P. malainoides might have undergone biased concerted evolution toward one of its parent P. wrightii, and P. intortusifolius might be a synonymy of P. × anguillanus. [ABSTRACT FROM AUTHOR]

Turkish representatives of the genus Rhaponticoides Vaill. are examined. A key and distribution map of Rhaponticoides species occurring in Turkey are provided for the first time. R. hierroi Ö. Eren sp. nov., from Bakacak pass in the Western Taurus range, SW Anatolia, allied to R. mykalea (Hub.-Mor.) M. V. Agab. & Greuter is described as a species new to science and illustrated. Its habitat conditions and conservation status are considered. Pollen micrographs of R. hierroi and R. mykalea are presented using scanning electron microscopy. [ABSTRACT FROM AUTHOR]

The taxonomic status of Central European taxa Festuca pallens s.l., F. psammophila, F. polesica, and F. vaginata was revised using the multivariate morphological analysis of well karyologically documented plants, and AFLP analysis. Six species were recognised: F. pallens Host (relict rocky habitats; diploid); F. csikhegyensis Simonk. (base-rich rocks; tetraploid); F. psammophila (Čelak.) Fritsch (acidic sands) with two subspecies, F. p. subsp. psammophila (E Germany, Poland, Bohemia) and F. p. subsp. dominii (Krajina) P. Šmarda (SW Moravia, NE Austria, SW Slovakia, C and E Poland); F. vaginata Willd. (base-rich sands mainly in the Pannonian Lowland); F. polesica Zapał. (seaside and inland sand dunes); and F. pseudovaginata Penksza (base-rich sands in the Pannonian Lowland). Identification key and distribution maps as well as informations about type specimens, exsiccata collections, synonyms, and hybrids are provided. Evolutionary relationships with the assumed putative ancestor F. pallens and the rather isolated position of F. polesica are discussed. [ABSTRACT FROM AUTHOR]

The wild common bean ( Phaseolus vulgaris) is widely but discontinuously distributed from northern Mexico to northern Argentina on both sides of the Isthmus of Panama. Little is known on how the species has reached its current disjunct distribution. In this research, chloroplast DNA polymorphisms in seven non-coding regions were used to study the history of migration of wild P. vulgaris between Mesoamerica and South America. A penalized likelihood analysis was applied to previously published Leguminosae ITS data to estimate divergence times between P. vulgaris and its sister taxa from Mesoamerica, and divergence times of populations within P. vulgaris. Fourteen chloroplast haplotypes were identified by PCR-RFLP and their geographical associations were studied by means of a Nested Clade Analysis and Mantel Tests. The results suggest that the haplotypes are not randomly distributed but occupy discrete parts of the geographic range of the species. The current distribution of haplotypes may be explained by isolation by distance and by at least two migration events between Mesoamerica and South America: one from Mesoamerica to South America and another one from northern South America to Mesoamerica. Age estimates place the divergence of P. vulgaris from its sister taxa from Mesoamerica at or before 1.3 Ma, and divergence of populations from Ecuador-northern Peru at or before 0.6 Ma. As these ages are taken as minimum divergence times, the influence of past events, such as the closure of the Isthmus of Panama and the final uplift of the Andes, on the migration history and population structure of this species cannot be disregarded. [ABSTRACT FROM AUTHOR]

Biebersteiniaceae comprise a single genus with four species of perennial herbs occurring from central Asia to Greece. A previous molecular phylogenetic study placed one of the species in an isolated position in Sapindales, while morphological studies had placed Biebersteinia in or near Geraniaceae, albeit doubtfully. We tested the monophyly and placement of the family with data from the chloroplast genes rbcL and atpB obtained for all four species, other major clades of Sapindales and outgroups for a total of up to 114 taxa. Parsimony, Bayesian, and likelihood analyses place Biebersteinia in Sapindales, possibly as sister to the other eight families. Strict and relaxed molecular clocks constrained with fossils of Biebersteinia and up to eight other Sapindales suggest that the Biebersteinia crown group diversified in the Oligocene and Miocene, while the stem lineage dates back to the Late Paleocene. Ages for other sapindalean families are earlier than those obtained in more sparsely sampled analyses, although estimates for Burseraceae agree surprisingly well. Ancestral area analyses suggest that Biebersteinia expanded from the eastern part of its range (i.e. Tibet and Inner Mongolia) to the west, although analyses are hampered by the unclear sister group relationships. [ABSTRACT FROM AUTHOR]

European white oak species ( Quercus subg. Lepidobalanus) are known to share a substantial part of the nuclear and cytoplasmic genome. In spite of this fact, they have preserved their integrity. We analyzed genetic variation at thirteen isozyme loci in nine Quercus robur, ten Q. petraea, two Q. pubescens and two mixed (two-species) populations in Slovakia to assess the extent of allele sharing. Moreover, a detailed morphometric study based on thirteen leaf traits was done in the mixed stands. A Bayesian analysis of population structure in the set of pure populations revealed the existence of three clusters, which coincided with the supposed taxonomical identity of populations. However, the distribution of posterior probabilities of data was bimodal with a second peak at six groups, what indicates a possible substructure in the gene pools of the investigated oak species. Moreover, gene admixture was close to 50% in all investigated populations. Morphometric analysis of the two mixed stands revealed a clear morphological separation of the studied oak species, sharply contrasting with a high degree of gene admixture. Differentiation is not uniformly distributed over the genome. High levels of differentiation ( F ST > 0.10) were observed at only three out of thirteen loci. The hypotheses explaining extensive allele sharing (shared ancestral polymorphisms vs. high levels of interspecific gene flow) are briefly discussed. [ABSTRACT FROM AUTHOR]

As a member of the Sanguisorbinae, taxonomically complicated Polylepis Ruiz & Pav. from the South American Andes is one of the few wind-pollinated genera of Rosaceae. Here, it is suggested that problems traditionally faced in species delimitation and phylogeny reconstruction may be in part due to a combination of weak reproductive barriers and the large distances that can be covered by genetic information as a result of wind pollination. The pattern of species distribution as well as molecular data (AFLP) of Polylepis were contrasted with those of an unrelated, insect-pollinated genus of similar species number and distribution, Minthostachys (Griseb.) Spach (Lamiaceae). In the present case, extensive pollen-mediated gene flow may explain the homogenization of genetic variability over larger distances and a lower number of species restricted to individual countries in the wind-pollinated genus Polylepis, but more examples will have to be studied before arriving at final conclusions. [ABSTRACT FROM AUTHOR]

Maximum parsimony and Bayesian likelihood analysis of ribosomal DNA internal transcribed spacer (ITS) sequences from 55 samples representing 25 species, subspecies, and/or hybrids of Tropaeolum sect. Chilensia yielded a tree with a large proportion of well-supported nodes at the interspecific and intersubspecific level. However, the tree shows samples from two species, T.azureum and T. brachyceras, arising in two different positions. Samples representing subspecies of T. hookerianum and T. leptophyllum suggest that these species are polyphyletic. The data corroborate evidence for hybridization between T. brachyceras and T. tricolor. Consideration of interfertility data, past and present Chilean ecology, and empirical evidence for the behavior of phenotypic and genotypic characters in known hybrids suggest a high likelihood that reticulate evolution has played a role in the diversification of T. sect. Chilensia. This reticulate evolution may explain the discordance between the ITS tree and the conventional taxonomy. High divergence in ITS sequences between T. sect. Chilensia and other members of Tropaeolum prohibits reliable outgroup-rooting, but midpoint rooting places the root at a partition comprising taxa whose distribution conforms to a relictual eastern-western South American disjunction described for other taxa. Within the Chilean taxa, the analysis suggests that biogeographic diversification has been from the mesophytic southern habitats northward to central mediterranean and northern arid zones. [ABSTRACT FROM AUTHOR]

Paspalum simplex is a grass distributed throughout the phytogeographic Chaco region in South America from which sexual diploid and apomictic tetraploid races have been reported. We analysed native populations to determine their homogeneity of ploidy level, and the relationship between geographic distribution, ploidy levels, and reproductive systems. The ploidy level was established for 379 plants from 32 wild populations. Tetraploidy and apomixis constitute the most common combination for this species all over the Chaco region. Apomictic hexaploid plants were found associated with 4x populations. Diploids were confined to a small sector of the region. One sexual triploid plant arose from seed harvested in a pure 2x population, and one apomictic 3x plant was found in a mixed 2x-4x population. The results suggest that P. simplex is a core agamic complex characteristic of the Chaco region from which other apomictic polyploid species of the subgenus Anachyris could have evolved. [ABSTRACT FROM AUTHOR]

The flavonoid profiles of seven species of Abrotanella and one species of Ischnea have been shown to be based upon kaempferol 3- and quercetin 3- O-glycosides and a delphinidin glycoside. Glucosides, glucuronides, arabinosides, diglucosides, and rutinosides of the flavonols were identified. The profile of Ischnea consisted solely of quercetin 3- O-glucoside and 3- O-arabinoside whereas the profiles of the Abrotanella species were more varied. Although infraspecific variation was not investigated in this study, the flavonoid chemistry of the two genera is in accordance with the flavonoid variation described for other members of Senecioneae which are primarily flavonol producers. Based on the known phylogeny and biogeography, the flavonoid distribution from the perspective of long-distance dispersals across the Pacific is discussed. Such events should lead to genetic bottle-neck situations and depauperate flavonoid profiles. A summary of current flavonoid knowledge in the Senecioneae is supplied. [ABSTRACT FROM AUTHOR]

104 populations of 15 Nordic species (2x-16x) of the taxonomically complex genus Draba were investigated using enzyme electrophoresis. The polyploids were genetic alloploids showing high levels of fixed heterozygosity and electrophoretic variation; the diploids were homozygous and genetically depauperate. Thus, the data suggest that alloploidy in arctic-alpine Draba serves as an escape from genetic depauperation caused by inbreeding at the diploid level. Although some populations probably have local alloploid origins, electrophoretic data indicate that several polyploids have migrated repeatedly into the Nordic area. Draba crassifolia (2n = 40) is probably octoploid based on x = 5. A hypothesis on the evolutionary history of the polyploids based on x = 8 is presented. Diploids contributing to numerous polyploid genomes and multiple origins of polyploids have seriously blurred taxonomic relationships. Relationships inferred from genetic data do not always correspond to those based on morphology; two morphologically very similar polyploids, D. alpina and D. oxycarpa, were, for example, genetically distant and probably represent independent lineages. [ABSTRACT FROM AUTHOR]

The leaf-anatomy, palynology, seed-morphology, vegetative morphology and especially the highly complicated floral morphology of the Coryciinae s. str. ( Diseae: Orchidoideae: Orchidaceae) are described and illustrated in detail. On the basis of these characters the presumed phylogeny, based on a rigorous cladistic analysis, is presented. The cladistic biogeographical analysis of the Coryciinae s. str. shows that it is a member of the Afrotemperate Track, with a pattern of vicariance events typical of the members of this track. An analysis of the patterns of speciation shows that allopatric speciation appears to be rare, and that parapatric speciation across edaphic boundaries may be the most important factor. Proceeding from the information presented, a new classification of the group is proposed in which we recognize the four genera Ceratandra, Evotella, Pterygodium and Corycium. The new monotypic genus Evotella comprises a species originally described as Pterygodium rubiginosum. The three species of the genus Anochilus are transferred to Corycium and Pterygodium. P. magnum, which was originally described as Pterygodium but was transferred to Corycium lately, is placed in a monotypic section of Pterygodium. [ABSTRACT FROM AUTHOR]

Cyclamen somalense Thulin & Warfa, spec. nova, the first member of the genus known from tropical Africa, is described from the Al Miskat Mts in NE. Somalia. The new species is closely related to the E. Mediterranean C. persicum Mill. The disjunct Mediterranean element in the mountain flora of northern Somalia, to which C. somalense belongs, is believed to be largely a relict of Tertiary origin. [ABSTRACT FROM AUTHOR]

The assembly of Mediterranean pines in the sense of Mirov is inhomogeneous in respect to morphological, geographical and evolutionary affinities. Considering new or neglected characters (vegetative and particularly reproductive, cone scales, apophyses, mucros, seeds: Figs. 1-3) in extant populations and fossils, three groups are recognized. The group of coast and island pines extends from the Canary islands to the Himalaya region and is closely related to Caribbean and C. American taxa. This complex evidently has originated from haploxyl ancestors of sect. Parrya during the Mesozoic (Upper Jurassic/Lower Cretaceous) in the NW. Tethys area (Fig. 13). P. rzedowskii can be regarded as an extant survivor of this first phase of differentiation. The extremely variable P. canariensis (together with P. roxburghii in sect. Sula) marks a transitional phase towards the more advanced diploxyl species of sect. Pinea (with P. pinea, P. halepensis & P. brutia, and subsect. Oocarpae) and sect. Pinaster (with P. pinaster, etc.) (Figs. 4-12).-The second group consists of diploxyl mountain pines from the areas surrounding the Mediterranean. They are classified as members of the Eurasiatic sect. Pinus subsect. Sylvestres, have differentiated along the northern Parathetys area, and exhibit close links with E. Asiatic taxa. The third group includes the haploxyl mountain pines P. cembra and P. peuce which can be regarded as western outposts of the circumpacific centred sect. Strobus with a pre-Tertiary origin.-As an appendix, an improved classification scheme is presented for the pine groups discussed. [ABSTRACT FROM AUTHOR]

The evolution and taxonomic relationships in the Triticeae are discussed with the view to highlight aspects of this agronomically important group of plants, which may be of interest to molecular biology. Some of these aspects are addressed in more detail in adjoining papers in which specific genomic loci have been examined at the DNA sequence or isozyme level. Aspects discussed include the systematics and geographic distribution of the Triticeae species, isozyme and chromosome pairing studies on some of the species as well as more recent developments in DNA analyses. A survey of the systematics of the Triticeae indicated that the genomic system of Löve is probably the most useful starting point for interpreting molecular data even though the system has many problems from a taxonomic point of view. The geographical distribution of Triticeae species, using both published and unpublished data, suggested that information of this type taken together with the theory of continental drift provides a broad time-span for considering data from DNA sequence studies. The significance, and modes of analyses, of isozyme studies were assessed because they often provide valuable characters in determining relationships between species. The main character underlying Löve's and Dewey's analyses of the Triticeae, namely chromosome pairing, is discussed with particular reference to isozyme studies to show that in some cases, such as species of Hordeum sensu lato, consistent relationships are obtained. Finally, new developments in understanding chromosome structure are considered in relation to the above variables in the taxonomy and evolution of the Triticeae. [ABSTRACT FROM AUTHOR]

The phytogeographical territories of Israel and Sinai are revised using a large mass of species distribution data. With the help of chorotype frequencies for 25 km individual squares in Israel, territories were defined on the basis of the first two most frequent chorotypes. The similarity of boundaries in the resulting phytogeographical map with a physiognomic map suggests that the latter may be used in preliminary stages of the preparation of plant geographical maps. [ABSTRACT FROM AUTHOR]

Hypericum dogonbadanicum Assadi, a local species from the Quercus brandtii forests of the Zagros Mountains in south-western Iran, belongs to sect. Campylosporus ( Spach) R. Keller and is most closely related to a Socotran endemic, H. socotranum Good subsp. smithii N. Robson. Despite the inclusion of these forests in the Irano-Turanian Element of the Iran flora by Zohary (1963), H. dogonbadanicum appears to belong rather to the Mediterranean dwarf-shrub maquis type of community and therefore to be a member of Zohary's (1963) Mediterranean/Irano-Turanian group of Iranian species.-The key position of the Socotran endemics to the understanding of the inter-sectional relationships is discussed. [ABSTRACT FROM AUTHOR]

The geographic variation in Fritillaria graeca, an endemic of Greece, is explored, using multivariate techniques. Eleven morphological features were measured in each of 630 individual plants from 38 localities throughout the range of the species. Scheffe's a posteriori test revealed an almost continuous geographic variation and did not identify groups clearly. Discriminant analysis of the groups derived from an F significance test of Mahalanobis distance resulted in five major groups on the first two discriminant axes representing the subspecies graeca, ionica, guicciardii, thessala and its var. othria. A diagnostic key to the F. graeca subspecies is provided. [ABSTRACT FROM AUTHOR]

Nucleotide sequences from the internal transcribed spacer (ITS) regions of the 18S–26S nuclear ribosomal DNA have been studied from ten species of Quercus (representing four subgenera), Castanea sativa and Fagus sylvatica, as a preliminary molecular contribution to the still poorly understood systematics and evolution of Fagaceae. The resulting matrix has been used to calculate pair-wise sequence divergence indices and to construct a maximum parsimony tree for Quercus coding indels as a fifth state. Divergence is greater for Quercus vs. Fagus than for Quercus vs. Castanea. The tree for the Quercus taxa studied reveals two clearly divergent clades. In clade I the evergreen W Mediterranean Q. suber appears in a basal position as sister to more distal deciduous taxa, i.e. the E Mediterranean Q. macrolepis and the E Asiatic Q. acutissima (all formerly united as different sections under the apparently polyphyletic subg. Cerris), and Q. rubra (a representative of the N American subg. Erythrobalanus), forming a pair with Q. acutissima. In clade II the evergreen southeastern N American Q. virginiana is basal and sister to the remaining three branches, i.e. a pair of evergreen Mediterranean taxa with Q. ilex and Q. coccifera (subg. Sclerophyllodrys), the deciduous but otherwise plesiomorphic SE European/SW Asiatic Q. cerris (type species of subg. Cerris), and the related but more apomorphic European pair Q. petraea and Q. robur (subg. Quercus). These results partly conflict with current taxonomic classification but are supported by some anatomical and morphological characters. They document polyphyletic lines from evergreen to deciduous taxa and suggest Tertiary transcontinental connections within the genus. [ABSTRACT FROM AUTHOR]

Photosynthetic pathways are reported for 305 species of Chenopodiaceae from Africa, Asia and Europe. Ecological characteristics, phytogeography and life forms of all species are given, and their correlation with relevant CO2-fixation types are discussed. 205 species (67.2%) exhibit the C4-pathway and 100 species (32.8%) the C3-pathway of CO2-fixation. Most of the C4 species are of Irano-Turanian origin. The diversity of C4 species of the Irano-Turanian phytochoria, with very harsh winters, are interpreted by the active period of Chenopods in summer. There is a close relationship between some special morphotypes and respective photosynthetic type. Halophytes and xerophytes with articulated stems and stem succulents of Anabasis-type are exclusively C4. Leaf succulent halophytes and xerohalophytes are predominantly C4. Hygrohalophytes with leaf or stem succulence are often C3. Probably many C4 Salsoleae have been evolved in the Afroasiatic arid zone after the climatic changes of the Miocene. Among them there is a high proportion of annuals that have a younger origin. There is some evidence that the present Chenopods of the subfamily “ Salsoloideae” may have their ancient stock in NW Africa. We found close taxonomic relationships between photosynthetic pathways and infrageneric classification in genera with both types of C3 and C4, like Atriplex and Suaeda. [ABSTRACT FROM AUTHOR]