Peroxidasemuster und Systematik vonArgyranthemum undChrysanthemum s. str. (Asteraceae-Anthemideae)

Leaf extracts of several taxa ofArgyranthemum (nanophaneroand chamaephytes endemic to the Macaronesian Islands) andChrysanthemum s. str. (therophytes of the West Mediterranean region) were subjected to polyacrylamide disc gel electrophoresis and analysis of peroxidase isoenzymes. The differences between the two genera are small; this points to their close affinity. The taxonomic subdivision ofChrysanthemum s. str. is confirmed. ForArgyranthemum the inclusion ofA. callichrysum andA. ochroleucum into sect.Ismelia is suggested.A. foeniculaceum may fit better into the otherwise isolated sect.Monoptera but somewhat approaches sect.Ismelia. Isoenzyme patterns inA. frutescens s. l. seem to reflect a geographical differentiation of the group on 5 Canary Islands.

     

Origin and evolution of the endemic Macaronesian Inuleae (Asteraceae): evidence from the internal transcribed spacers of nuclear ribosomal DNA

The tribe Inuleae (Asteraceae) has 10 species endemic to the Macaronesian islands, including the three endemic genera Allagopappus, Schizogyne, and Vierea. Phylogenetic analyses of DNA sequence data from the internal transcribed spacers (ITS) of the nuclear ribosomal DNA of 47 taxa were performed using all Macaronesian endemics and representative species from 21 of the 36 genera of the Inuleae. The resulting ITS phylogeny reveals that Allagopappus is sister to a large clade that contains all genera with a predominantly Mediterranean distribution. This finding suggests that Allagopappus may represent an ancient lineage that found refuge in the Canary Islands following the major climatic and/or geologic changes in the Mediterranean basin after the Tertiary. The Macaronesian endemic genus Schizogyne is sister to Limbarda from the Mediterranean. The third Macaronesian endemic genus, Vierea, is sister to Perralderia, which is restricted to Morocco and Algeria. Pulicaria canariensis is sister to P. mauritanica, a species endemic to Morocco and Algeria. In contrast, P. diffusa from the Cape Verde Islands is sister to a broadly distributed species, P. crispa, that occurs from North Africa to the Arabian peninsula. Based on the ITS data, the genera Blumea, Inula, and Pulicaria are not monophyletic. The ITS trees suggested that Blumea mollis belongs to the tribe Plucheeae, a finding that is congruent with recent morphological evidence. A possible southern African origin for the core of the Laurasian taxa of the Inuleae is also suggested.     

Isozyme differentiation in the endemic genusArgyranthemum (Asteraceae: Anthemideae) in the Macaronesian Islands

The genusArgyranthemum (Asteraceae: Anthemideae) comprises 38 taxa and is restricted to the archipelagos of the Canaries, Selvagens, Madeira, and Desertas in the Macaronesian biogeographic region. An electrophoretic study, including 17 enzyme loci and at least one population of each of the described taxa, was carried out. High identity (low distance) values between taxa (mean of 0.893) were obtained despite the old age of the islands, their close proximity to the African continent, and the fact thatArgyranthemum is the most species-rich and variable genus in Macaronesia. These results suggest that the genus is monophyletic and that it has evolved very rapidly in these islands. There is little correspondence between taxonomy and neighbor-joining analysis based on Roger's genetic distances, but in several instances populations from the same islands cluster together despite being from different species or even different sections. It is suggested that repeated genetic bottlenecks associated with the founding of new populations during radiation of the genus resulted in lineage sorting of ancestral allozyme polymorphisms. Because every population has a high average identity with all other populations, lineage sorting could result in populations of different taxa being slightly more similar than populations of the same taxon. Gene flow between different species on the same island could account for some populations clustering by island of origin rather than taxonomic disposition. Average allozyme diversity within populations (0.098) is 50% higher than the mean total diversity for species endemic to oceanic islands.     

Recent origin,active speciation and dispersal for the lichen genus Nephroma (Peltigerales) in Macaronesia

Aim We reconstructed the phylogeny of the lichen genus Nephroma (Peltigerales) to assess the relationships of species endemic to Macaronesia. We estimated dates of divergences to test the hypothesis that the species arose in Macaronesia (neo‐endemism) versus the oceanic archipelagos serving as refugia for formerly widespread taxa (palaeo‐endemism). Location Cosmopolitan with a special focus on the archipelagos of the Azores, Madeira and the Canary Islands. Methods DNA sequences were obtained from 18 species for three loci and analysed using maximum parsimony, maximum likelihood and Bayesian inferences. Divergence dates were estimated for the internal transcribed spacer (ITS)‐based phylogeny using a relaxed molecular clock. Reconstruction of the ancestral geographical range was conducted using the Bayesian 50% majority rule consensus tree under a parsimony method. Results The backbone phylogenetic tree was fully supported, with Nephroma plumbeum as sister to all other species. Four strongly supported clades were detected: the Nephroma helveticum, the N. bellum, the N. laevigatum and the N. parile clades. The latter two share a common ancestor and each includes a widespread Holarctic species (N. laevigatum and N. parile, respectively) and all species endemic to Macaronesia. The data suggest a neo‐endemic origin of Macaronesian taxa, a recent range expansion from Macaronesia of both widespread species, a range expansion limited to the Mediteranean Basin and south‐western Europe for another taxon, and a long dispersal event that resulted in a speciation event in the western parts of North America. Main conclusions The Macaronesian endemic species belong to two sister clades and originated from a most recent common ancestor (MRCA) shared with one widely distributed taxon, either N. parile or N. laevigatum. Estimates of the mean divergence dates suggest that the endemics originated in the archipelagos after the rise of the volcanic islands, along with the ancestor to the now widespread species, which probably expanded their range beyond Macaronesia via long‐distance dispersal. This study provides the first phylogenetic evidence of Macaronesian neo‐endemism in lichenized fungi and provides support for the hypothesis that oceanic islands may serve as a source for the colonization of continents. However, further data are needed to properly assess the alternative hypothesis, namely colonization from western North America.     

Phylogenetics of Eulophiinae (Orchidaceae: Epidendroideae): evolutionary patterns and implications for generic delimitation

Eulophiinae comprise c. 270 species divided into nine genera, with the species‐rich terrestrial genus Eulophia representing 60% of this diversity. Remarkable ecological and morphological variation, and an absence of clear diagnostic characters have led to uncertain generic delimitation in the subtribe. Using a combination of new and previously published DNA sequences, we created a dataset representing 122 taxa and all genera of Eulophiinae and inferred a complete generic‐level phylogeny for the subtribe for the first time. Our sampling focused on analysing Afro‐Madagascan taxa and therefore included representatives of the four mostly epiphytic Madagascan endemic genera, the near Madagascan endemic Oeceoclades and additional sampling of the predominantly African genera Eulophia and Orthochilus. In total, 104 new accessions were collected for this study in Zambia and Madagascar (88 of which represented 36 Eulophia spp. and 12 Oeceoclades spp.). Independent plastid and nuclear phylogenetic trees were inferred using Bayesian and maximum‐likelihood algorithms, which recovered strong support for a monophyletic Eulophiinae, the first‐branching position of the mostly epiphytic Madagascan endemic genera, and increased support for recognition of the terrestrial genera Oeceoclades and Orthochilus. Eulophia, the largest genus in the group, was recovered as polyphyletic, but with implications for its classification and that of Geodorum, that was nested in the main Eulophia clade. Although relationships among several genera were resolved with some confidence, the positions of the South African endemic genus Acrolophia and the epiphytic Madagascan endemic Paralophia require further work. Taxon sampling of Asian Eulophia is a priority for future work on the systematics of this group. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 43–56.     

Molecular evidence for a Mediterranean origin of the Macaronesian endemic genus Argyranthemum (Asteraceae)

The internal transcribed spacers (ITS) of nuclear ribosomal DNA were sequenced for 52 species from 32 genera and eight subtribes of Anthemideae. Phylogenetic analyses of ITS data generated trees that are largely incongruent with the recent classification of Anthemideae; most of the subtribes examined are not resolved as monophyletic. However, ITS trees are congruent with morphological, isozyme, phytochemical, and chloroplast DNA (cpDNA) restriction site data in supporting a Mediterranean origin for Argyranthemum, the largest endemic genus of the Atlantic oceanic islands. A combined analysis of ITS sequences and cpDNA restriction sites indicates that Argyranthemum is sister to the other three genera of Chrysantheminae (i.e., Chrysanthemum, Heteranthemis, and Ismelia). Times of divergence of Argyranthemum inferred from the ITS sequences ranged between 0.26 and 2.1 million years ago (mya) and are lower than values previously reported from isozyme and cpDNA data (1.5-3.0 mya). It is likely that rate heterogeneity of the ITS sequences in the Anthemideae accounts for the low divergence-time estimates. Comparison of data for 20 species in Argyranthemum and Chrysantheminae indicates that the cpDNA restriction site approach provided much more phylogenetic information than ITS sequences. Thus, restriction site analyses of the entire chloroplast genome remain a valuable approach for studying recently derived island plants.     

Intercontinental disjunctions in Cryptotaenia (Apiaceae, Oenantheae): an appraisal using molecular data

Aim The angiosperm genus Cryptotaenia (family Apiaceae, tribe Oenantheae) exhibits an anomalous distribution pattern, with five of its eight species being narrow endemics geographically isolated from their presumed relatives. We examined the monophyly of the genus and ascertained the phylogenetic placements of its constituent members in order to explain their distribution patterns. Location Eastern North America, eastern Asia, the Caucasus, southern Italy, Macaronesia and Africa. Methods In total, 173 accessions were examined for nuclear rDNA ITS sequence variation, representing nearly all major lineages of Apiaceae subfamily Apioideae and seven species of Cryptotaenia. Sampling of tribes Oenantheae, Scandiceae and Pimpinelleae was comprehensive. Phylogenetic analyses included Bayesian, maximum parsimony and neighbour‐joining methods; biogeographical scenarios were inferred using dispersal–vicariance analysis (diva ). Results Cryptotaenia is polyphyletic and includes three distant lineages. (1) Cryptotaenia sensu stricto (C. canadensis, C. japonica, C. flahaultii and C. thomasii) is maintained within tribe Oenantheae; C. canadensis and C. japonica, representing an eastern North American–eastern Asian disjunction pattern, are confirmed to be sister species. (2) Cryptotaenia elegans, endemic to the Canary Islands, is placed within Scandiceae subtribe Daucinae along with two woody endemics of Madeira, Monizia edulis and Melanoselinum decipiens. The phylogeny of these Canarian and Madeiran endemics is unresolved. Either they constitute a monophyletic sister group to a clade comprising some Mediterranean and African species of Daucus and their relatives, or they are paraphyletic to this clade. The herbaceous/woody genus Tornabenea from Cape Verde, once included in Melanoselinum, is not closely related to the other Macaronesian endemics but to Daucus carota. (3) The African members of Cryptotaenia (C. africana, C. calycina and possibly C. polygama) comprise a clade with some African and Madagascan umbellifers; this entire clade is sister group to Eurasian Pimpinella. Main conclusions Elucidating the phylogeny of the biogeographically anomalous Cryptotaenia sensu lato enabled hypotheses on the biogeography of its constituent lineages. Cryptotaenia sensu stricto exhibits a holarctic distribution pattern, with its members occurring in regions that were important glacial refugia. The genus probably originated in eastern Asia and from there dispersed to Europe and North America. For the Macaronesian endemic species –C. elegans, M. edulis and M. decipiens–diva reconstructs either a single dispersal event to Macaronesia from the Mediterranean/African region, or a single dispersal followed by a back‐dispersal to the mainland. The radiation of Tornabenea from Cape Verde followed a second dispersal of Daucinae to Macaronesia. Woodiness in Melanoselinum/Monizia and Tornabenea, therefore, is a derived and independently acquired trait. The African members of Cryptotaenia are derived from an ancestor arriving from the Middle East.     

A phylogenetic analysis of the palm subtribe Oncospermatinae (Arecaceae) based on morphological characters

Subtribe Oncospermatinae (Arecaceae: Arecoideae: Areceae) is a diverse group of spiny Old World palms. The subtribe includesOncosperma, a widespread Asian genus of five species, along with seven monotypic genera, all endemic to the Seychelles and Mascarene Islands of the western Indian Ocean. A phylogenetic analysis was conducted in order to test the monophyly of subtribe Oncospermatinae with respect to other Old World genera of tribe Areceae. A matrix of 38 morphological characters was scored for 29 taxa, including 11 species of the Oncospermatinae. A single most parsimonious tree was found, resolving the subtribe as a polyphyletic group of two distinct clades. One clade containingAcanthophoenix, Deckenia, Oncosperma, andTectiphiala was placed as sister to a large group that includes members of subtribes Archontophoenicinae, Arecinae, Iguanurinae, and Ptychospermatinae. The other clade of Oncospermatinae, including the Seychelles endemic generaNephrosperma, Phoenicophorium, Roscheria, andVerschaffeltia, was resolved as sister to the Madagascar endemic subtribe Masoalinae, and may have arisen in the western Indian Ocean region.     

AND IF ENGLER WAS NOT COMPLETELY WRONG? EVIDENCE FOR MULTIPLE EVOLUTIONARY ORIGINS IN THE MOSS FLORA OF MACARONESIA

The Macaronesian endemic flora has traditionally been interpreted as a relict of a subtropical element that spanned across Europe in the Tertiary. This hypothesis is revisited in the moss subfamily Helicodontioideae based on molecular divergence estimates derived from two independent calibration techniques either employing fossil evidence or using an Monte Carlo Markov Chain (MCMC) to sample absolute rates of nucleotide substitution from a prior distribution encompassing a wide range of rates documented across land plants. Both analyses suggest that the monotypic Madeiran endemic genus Hedenasiastrum diverged of other Helicodontioideae about 40 million years, that is, well before Macaronesian archipelagos actually emerged, in agreement with the relict hypothesis. Hedenasiastrum is characterized by a plesiomorphic morphology, which is suggestive of a complete morphological stasis over 40 million years. Macaronesian endemic Rhynchostegiella species, whose polyphyletic origin involves multiple colonization events, evolved much more recently, and yet accumulated many more morphological novelties than H. percurrens. The Macaronesian moss flora thus appears as a complex mix of ancient relicts and more recently dispersed, fast‐evolving taxa.     

Molecular phylogeny in endemic weevils: revision of the genera of Macaronesian Cryptorhynchinae (Coleoptera: Curculionidae)

A molecular phylogeny and lineage age estimates are presented for the Macaronesian representatives of the weevil subfamily Cryptorhynchinae, using two mitochondrial genes (cytochrome c oxidase subunit 1 and 16S). The Bayesian reconstruction is supplemented by observations on morphology, ecology, and reproductive biology. The present study often corroborates the groups previously outlined in higher‐level informal taxonomies. These and further groups are now assigned new taxonomic status. The following genera and subgenera are described (formerly Acalles): Aeoniacalles gen. nov. , Canariacalles gen. nov. , Ficusacalles gen. nov. , Madeiracalles gen. nov. , Silvacalles gen. nov. (with Tolpiacalles subgen. nov. , Tagasastacalles subgen. nov. ), Sonchiacalles gen. nov. , Echiumacalles gen. nov. (monotypic), Lauriacalles gen. nov. (monotypic), and Pseudodichromacalles gen. nov. (monotypic; formerly Dichromacalles). For the western Palaearctic genus Acalles Schoenherr, 1825 the first subgenus Origoacalles subgen. nov. is described and for the genus Onyxacalles Stüben, 1999 the first subgenus Araneacalles subgen. nov. ; Paratorneuma Roudier 1956 resyn. Except for one species of Acalles (Origoacalles), all of these new higher taxa are endemic to the Macaronesian Islands. All new taxa are presented, together with their host plants and further data, in a synoptic tabular overview. Based on the results of our phylogenetic analysis, we advocate the hypothesis that the evolution of the species in the new genera (of which most group into a ‘Macaronesian clade’) began in the comparatively arid succulent bush zone and that the shady and humid laurel forest of the thermo‐Canarian and thermo‐Madeiran zone was entered much later. Our reconstruction implies that the Canarian and Madeiran archipelagos were colonized by Cryptorhynchinae at least seven times from the continent but saw only one considerable adaptive radiation. It also becomes apparent that it is the ancestor species of the genus Canariacalles– and not Pseudodichromacalles– that features a close connection to the south‐western European and north‐western African species of Dichromacalles s.s. Finally, a key is presented for all genera and subgenera of the Macaronesian Cryptorhynchinae. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 40–87.     

Bird–flower interactions in the Macaronesian islands

Aims Several bird‐pollinated or ornithophilous flowers are present on the Macaronesian archipelagos, the Canary Islands and Madeira, but absent from nearby NW Africa and Europe. In Macaronesia, no specialist nectar‐feeding birds are found, but several generalist passerine bird species visit flowers for nectar. Two hypotheses attempt to explain the origin and evolution of ornithophily in the Macaronesian flora. According to ‘the island de novo hypothesis’, bird‐flowers evolved from mainland insect‐pollinated ancestors after island colonization. Alternatively, ancestors of the ornithophilous Macaronesian plant species evolved bird‐flowers before reaching the islands (‘the relict hypothesis’). In this study we first compile information of Macaronesian bird–flower interactions from the literature and our own field observations. Secondly, we discuss the two hypotheses of origin of ornithophily in the light of evidence from recent molecular plant phylogenies, palaeontology, historical biogeography of the African avifauna and flora, and present‐day ecological patterns. Location Madeira and Canary Islands. Results At least eleven endemic Macaronesian plant species from six genera have typical ornithophilous floral traits. These genera are: Canarina and Musschia (Campanulaceae), Isoplexis (Scrophulariaceae), Echium (Boraginaceae), Lotus (Fabaceae) and Lavatera (Malvaceae). These lineages have clear affinities to the Mediterranean region, except for Canarina whose closest relatives grow in East African mountains. Six generalist passerine bird species of Sylvia, Phylloscopus (Sylviidae), Serinus (Fringillidae) and Parus (Paridae) visit this flora for nectar. Main conclusion We suggest that the origin and evolution of ornithophilous traits in these plant species took place mostly in mainland areas prior to island colonization. In Canarina and Lavatera, it is well supported that ornithophily is a relict condition, which originated in mainland areas possibly in association with specialist nectar‐feeding birds. For the remaining plant species except Echium wildpretii bird floral traits probably also are a relict condition. These species may be derived from ancestors, which were visited by specialist nectar‐feeding birds during geological periods when the Mediterranean and the Ethiopian vegetation were intermingled in mainland Africa. Probably, these mainland ancestors went extinct due to severe climatic fluctuations, while their Macaronesian descendants survived in ‘refuge’ on the islands. Finally, the island de novo hypothesis may explain the evolution of a mixed bird/insect‐pollination system in the neo‐endemic red‐flowered Echium wildpretii.     

From Scilla to Charybdis – is our voyage safer now?

The genus Charybdis Speta (previously Urginea maritima agg.) was investigated karyologically and genetically throughout its geographic range in the Mediterranean. The different ploidy levels show a strong geographic pattern. Diploid populations are mainly found along the northern coast of Africa with C. pancration extending northwards from Tunisia to southern Italy. Tetraploid populations are most densely distributed in the eastern Mediterranean but are also found in North Africa, on the Balearic and Canary Islands. Hexaploid populations are restricted to the Iberian Peninsula and adjacent Morocco and Algeria. Chloroplast microsatellite data suggest that determination of ploidy levels alone is insufficient to adequately describe the existing populations. Especially the tetraploid and hexaploid populations exhibit additional genetic differentiation and geographic structuring. AFLP data indicate that tetraploid populations from southern Italy are of hybrid origin. Phylogenetic analysis further revealed that the genera Urginea Steinh. and Charybdis are not directly related to each other but have strong ties to genera from southern Africa. A possible colonization scenario of the Mediterranean via NW Africa and Iberia is discussed.     

Origin of the Woody Macaronesian Sempervivoideae and the Phylogenetic Position of the East African Species of Aeonium

Evolutionary relationships among the genera of Macaronesian Sempervivoideae, Aeonium, Aichryson, Greenovia, and Monanthes, were studied using sequence variation of the chloroplast DNA trnL (UAA) - trnF (GAA) spacer and the nuclear ribosomal Internal Transcribed Spacer 2 (ITS2). Phylogenetic analysis indicates that the Moroccan Sedum sect. Monanthoidea is the sister taxon of the Macaronesian Sempervivoideae. In combination with the terminal position in the Macaronesian Sempervivoideae of the East African A. leucoblepharum, which has formerly been assumed to be the sister taxon of the other species of Macaronesian Sempervivoideae (i.e. Aichryson and Monanthes), a recent remigration to Africa is suggested. Statistical support for the terminal position of A. leucoblepharum using only spacer sequences is without homoplasy but not high since only single mutations in both the chloroplast and nuclear sequence characterize the clade containing A. leucoblepharum. A. leucoblepharum and the Canarian species with a similar growth-form share 50% of the RAPDs. Within a clade comprising woody species with yellow flowers and a herbaceous rosette, the highest genetic divergence, as determined with RAPDs, is found between A. simsii and the woody Macaronesian and African species. The extremely close genetic ties among the woody and branched (sub)shrubs indicate that, when compared to the other species of the genus, the woody, African Aeonium species are not the sister group of the Macaronesian Sempervivoideae and substantiate the view that an ancestor of A. leucoblepharum recently migrated from the Canary Islands to East Africa and Arabia through long distance dispersal, rather than being a relict of an African Aeonium flora from the Tertiary.     

Biogeographic patterns in Mediterranean and Macaronesian species of Saxifraga (Saxifragaceae) inferred from phylogenetic analyses of ITS sequences

A biogeographic study of Saxifraga section Saxifraga was performed based on phylogenetic analyses of ITS (internal transcribed spacer) sequences of nuclear ribosomal DNA. ITS sequences from 21 species and 31 populations were examined to identify colonization patterns for the two species of Saxifraga occurring in Macaronesia and for S. globulifera in the west Mediterranean basin. Phylogenetic analysis of the sequence data yield a single most parsimonious tree with many of the major clades well supported by bootstrap and decay values. The ITS tree provided resolution at specific and populational levels that points to two biogeographic patterns within the genus. In contrast to the molecular evidence provided by other authors for a Mediterranean origin of several Macaronesian genera of angiosperms, our results indicate that the Madeiran archipelago was colonized a single time by a species of Saxifraga originating from the Eurosiberian region. On the other hand, the molecular evidence also suggests that populations of S. globulifera from North Africa have been isolated for a long time from populations occurring in the Iberian Peninsula, and that the endemic S. reuteriana has evolved from the Iberian populations of S. globulifera. The Mediterranean Sea has probably been an effective isolating barrier for some plant groups that occur in Europe and North Africa.     

Febraina: a new subtribe of Alticini with cladistic analysis based on morphology (Coleoptera: Chrysomelidae: Galerucinae)

A new subtribe Febraina subtr.n. is established with Febra Clark designated as the type genus. Cladistic analysis based on morphological characters is carried out to reveal the composition of a new subtribe and to test its monophyly. Subtribe includes the following genera: Chilocoristes Weise; Halticorcus Lea; Setsaltica Samuelson; Maaltica Samuelson; Axillofebra Samuelson; Profebra Samuelson. Bionomical features of the genera of the subtribe are summarised. The syndrome of hemisphery is recorded for the genera of the subtribe, and morphological transformation resulting in hemisphery is described and discussed. Correspondence between direction of morphological transformation, phylogenetic arrangement of genera, and distributional pattern is recorded and discussed.     

Phylogeny of the Genus Chrysanthemum L.: Evidence from Single-Copy Nuclear Gene and Chloroplast DNA Sequences

Chrysanthemum L. (Asteraceae-Anthemideae) is a genus with rapid speciation. It comprises about 40 species, most of which are distributed in East Asia. Many of these are narrowly distributed and habitat-specific. Considerable variations in morphology and ploidy are found in this genus. Some species have been the subjects of many studies, but the relationships between Chrysanthemum and its allies and the phylogeny of this genus remain poorly understood. In the present study, 32 species/varieties from Chrysanthemum and 11 from the allied genera were analyzed using DNA sequences of the single-copy nuclear CDS gene and seven cpDNA loci (psbA-trnH, trnC-ycf6, ycf6-psbM, trnY-rpoB, rpS4-trnT, trnL-F, and rpL16). The cpDNA and nuclear CDS gene trees both suggest that 1) Chrysanthemum is not a monophyletic taxon, and the affinity between Chrysanthemum and Ajania is so close that these two genera should be incorporated taxonomically; 2) Phaeostigma is more closely related to the Chrysanthemum+Ajania than other generic allies. According to pollen morphology and to the present cpDNA and CDS data, Ajania purpurea is a member of Phaeostigma. Species differentiation in Chrysanthemum appears to be correlated with geographic and environmental conditions. The Chinese Chrysanthemum species can be divided into two groups, the C. zawadskii group and the C. indicum group. The former is distributed in northern China and the latter in southern China. Many polyploid species, such as C. argyrophyllum, may have originated from allopolyploidization involving divergent progenitors. Considering all the evidence from present and previous studies, we conclude that geographic and ecological factors as well as hybridization and polyploidy play important roles in the divergence and speciation of the genus Chrysanthemum.     

Molecular phylogeny ofCheirolophus (Asteraceae:Cardueae-Centaureinae) based on ITS sequences of nuclear ribosomal DNA

The genusCheirolophus has an interesting western Mediterranean and Macaronesian distribution. Here we investigate the delimitation of the genus and its exclusion from the large genusCentaurea, the systematic position of the related genusPaleocyanus, the delimitation of some species and the phylogeny of the group. We have carried out a phylogenetic analysis of the PCR-generated sequences of the internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA. The results suggest that the genus, includingPaleocyanus crassifolius is monophyletic; thus, a new combination of this species underCheirolophus is proposed. The Macaronesian group of species is also monophyletic, indicating a single colonization of the archipelago. The poor resolution of microspecies in the Macaronesian group reinforces the hypothesis of a very recent differentiation of the group.     

Relationships of the Macaronesian and Mediterranean floras: molecular evidence for multiple colonizations into Macaronesia and back-colonization of the continent in Convolvulus (Convolvulaceae)

A molecular phylogenetic analysis of the Macaronesian endemic species of Convolvulus was undertaken using data from the nuclear ribosomal internal transcribed spacer (ITS) regions. The results of the analysis support two introductions into Macaronesia from distantly related clades within Convolvulus and a subsequent back-colonization to the continent from within one of the clades. Hypothesized relationships between Macaronesian species and New World taxa and between the Canarian endemic C. caput-medusae and the Moroccan C. trabutianus are refuted. Both Macaronesian clades are shown to have Mediterranean sister groups although one is predominantly western Mediterranean and the other predominantly eastern Mediterranean in distribution. The patterns of colonization into Macaronesia demonstrated by Convolvulus and also by other multiple colonizing genera conform to either a pattern of phylogenetic distinctiveness or a checkerboard distribution of island lineages. Both are consistent with the hypothesis that niche preemption is responsible for the limited number of colonizations into the region. A review of sister group relationships demonstrates that, in common with Convolvulus, most Macaronesian groups have sister groups distributed in the near-continent (i.e., western Mediterranean). Disjunct sister group relationships (including Eastern Mediterranean disjunctions) occur in only 18% of groups.     

Two new taxa of subtribe Rhaconotina (Hymenoptera: Braconidae,Doryctinae, Doryctini) from Africa,with a key to subtribe genera

A new genus, Grangerdoryctes gen. n. (with type species Aivalykus niger Granger), from Madagascar and a new subgenus Pararhacon subgen. n. of the genus Rhaconotus Ruthe (type species R. (P.) haeselbarthi sp. n.) from South Africa are described and illustrated. A discussion of genera without a second radiomedial vein of the fore wing in the tribe Doryctini is presented. The position and content of the subtribe Rhaconotina are discussed and a key for determination of the genera of this subtribe is proposed.