Étude cytotaxinomique de quelquesDipsacaceae d'Iran

Chromosome numbers for 28 Iranian populations ofDipsacaceae, corresponding to 14 taxa, are presented. New are those forScabiosa aff.olivieri var.pinnatisecta, S. persica, Pterocephalus canus, P. kurdicus, Dipsacus strigosus, Cephalaria dichaetophora, C. hirsuta, C. microcephala, C. subindivisa andC. aff.sublanata. Except forC. syriaca (x = 5) andC. dichaetophora (x = 7 : new basic chromosome number forCephalaria), all species examined are characterized by the basic chromosome number (x = 9). Instances of aneusomaty, B-chromosomes, aneuploidy, dysploidy, and polyploidy have also been found.

     

Fruit differentiation, palynology, and systematics in theScabiosa group of genera andPseudoscabiosa (Dipsacaceae)

Fruits ofDipsacaceae are single-seeded, have bristle-shaped calyx segments and are tightly enclosed by four fused bracts forming an epicalyx. Comparative morphological and anatomical studies reveal a great diversity of epicalyx and calyx, often relevant to fruit dispersal. The present contribution deals with theScabiosa group of genera, the core of theScabioseae tribe. Most of its taxa develop a diaphragma from a meristem on the inside of the epicalyx. This diaphragma, together with the lower part of the epicalyx encloses the fruit proper, whereas the upper parts form a so-called epi-diaphragma (ed) and a ± hyaline corona. Differences of the epicalyx with respect to the size and position of the ed, elaboration of the corona, origin of pits (=foveoles) and other morphological and anatomical specializations can be demonstrated. Together with palynological and karyological data these new facts support an improved concept of relationships and systematics for the taxa studied:Scabiosa sect.Scabiosa and sect.Cyrtostemma are closely related and should be united to form the genusScabiosa s. str.;Pycnocomon can be maintained as an independent genus, sister toScabiosa sect.Trochocephalus which then has to be treated as a genus,Lomelosia. In contrast, the following genera have to be included inLomelosia:Tremastelma asLomelosia sect.Callistemma, andScabiosiopsis as part ofLomelosia sect.Lomelosia. Pseudoscabiosa deviates in so many features that it has to be excluded from the redefinedScabioseae s. str.     

Hybridisation,genomic constitution and generic delimitation inElymus s. l. (Poaceae: Triticeae)

Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJ^e, J^e, J^eJ^b, and J^b can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.     

Über die weite Verbreitung lichenisierter Sippen vonDictyochloropsis und die systematische Stellung vonMyrmecia reticulata (Chlorophyta)

Catinaria grossa is lichenized withDictyochloropsis splendida var.gelatinosa, var. nova. When cultured isolated from the fungus the cells of this variety are covered individually by thick gelatinous envelopes. The phycobionts ofMegalospora gompholoma subsp.gompholoma andM. atrorubicans subsp.australis belong to a new variety ofD. symbiontica, i.e. var.pauciautosporica, which preferentially reproduces by zoo- and aplanospores. The phycobiont ofPseudocyphellaria aurata does not belong toMyrmecia reticulata as formerly thought, but toDictyochloropsis symbiontica. Specimens from one locality in Tenerife and from New Zealand are lichenized with a strain ofD. symbiontica var.symbiontica, those from another locality in Tenerife with a strain ofD. symbiontica var.pauciautosporica. These strains differ in certain characters from other lichenized strains of these varieties.

     

Phylogenetic relationships of JapaneseAster (Asteraceae, Astereae) sensu lato based on chloroplast-DNA restriction site mutations

RFLPs of cpDNA were examined for 18 species ofAster, six species ofKalimeris, two species ofMiyamayomena and one species and one variety ofHeteropappus from Japan, using 16 restriction endonucleases. Approximately 275 restriction sites were surveyed, and a total of 74 restriction site mutations was detected, and 31 of these were phylogenetically informative. Sixteen most parsimonious trees constructed from Wagner parsimony analysis indicated the polyphyly ofKalimeris andMiyamayomena sensu Kitamura;K. miqueliana belongs to a different clade from the remaining species ofKalimeris, and two species ofMiyamayomena did not make a single clade. This result suggests that the shortening or loss of pappus have happened parallelly in different evolutionary lineages. We must be careful to assess the pappus character in taxonomy and phylogeny, and it is desirable to examine their phylogenetic relationships using a molecular data.     

Sero-systematics ofCytisus sect.Trianthocytisus (Fabaceae)

The serological reaction of seed proteins provides evidence for a partly new systematic arrangement ofCytisus sect.Trianthocytisus and ofCytisus s.l. Proposed modifications agree with recent advances in morphological taxonomy. Sect.Trianthocytisus includes only two species,C. villosus andC. aeolicus. Its position is central within the genus, and this fact agrees with the proposed retypification ofCytisus (type species:C. villosus).C. emeriflorus, formerly included in the same section, constitutes the monospecific sect.Emeroides, which is intermediate towards the genusLembotropis. This is serologically isolated and includes onlyL. nigricans. It is confirmed thatC. sessilifolius should be removed from the genusCytisus as a monospecific genus:Cytisophyllum Lang which is closely allied toHesperolaburnum and toPodocytisus, the most primitive genera ofGenisteae.     

Mycena auricoma,a new species ofMycena sectionRadiatae from Japan,andMycena spinosissima,a new record in Japan

Two lignicolous species ofMycena (Agaricales, Basidiomycetes) are described and illustrated from eastern, Japan:Mycena auricoma sp. nov., forming ephemeral coprinoid basidiomata and belonging to sectionRadiatae, was found on a dead fallen twig ofQuercus serrata. It appears to close to a Malaysian species,“Trogia” crinipelliformis. Mycena spinosissima in sectionSacchariferae, new to Japan, was collected from dead bark ofAphananthe aspera, a dead fallen inflorescence ofCryptomeria japonica, and a dead fallen twig ofQuercus serrata.     

Heterostyly in species ofNarcissus (Amaryllidaceae) andHugonia (Linaceae) and other disputed cases

The hypothesis ofHenriques andFernandes that several Iberian species ofNarcissus (Amaryllidaceae) are tristylous is reconsidered. Contrary to the opinion ofBateman and most subsequent authors, we believe that the available evidence indicates that some populations ofN. triandrus andN. fernandesii, at least, are tristylous; other populations ofN. triandrus are distylous.Hugonia cf.penicillanthemum (Linaceae) from new Caledonia is distylous, but it remains possible that other species ofHugonia are tristylous. The disputed occurrence of heterostyly in S. African species ofBauhinia (Leguminosae),Cleome (Capparaceae) andAneilema (Commelinaceae), and inAgelaea (Connaraceae) is discussed.     

Thehermit transposable element of the Australian sheep blowfly,Lucilia cuprina, belongs to thehAT family of transposable elements

We report the cloning ofhermit, a member of thehAT family of transposable elements from the genome of the Australian sheep blowfly,Lucilia cuprina. Hermit is 2716 bp long and is 49% homologous to the autonomoushobo element,HFL1, at the nucleic acid level.Hermit has 15 bp terminal inverted repeats that share 10 bp with the terminal inverted repeats ofHFL1. Conceptual translation reveals a 583 residue open reading frame (ORF) that is 64% similar and 42% identical to theHFL1 ORF. However, the sequence of thehermit element contains two frameshifts within the putative ORF, indication thathermit is an inactive element. Analysis ofL. cuprina strains from within and outside Australia suggested thathermit is present as a single copy in all the genomes analysed.     

Neue Beobachtungen zur Bestäubung vonOphrys (Orchidaceae) in Südspanien,mit besonderer Berücksichtigung des FormenkreisesOphrys fusca agg.

An investigation of pseudocopulation behaviour in species ofOphrys from southern Spain confirms the close relationship betweenCampsoscolia ciliata (Scoliidae) andOphrys speculum, and betweenEucera nigrilabris (Apoidea) andOphrys tenthredinifera. It could be demonstrated thatEucera barbiventris is the pollinator ofOphrys scolopax subsp.scolopax, whereas other species ofEucera andTetralonia which are active at the same time show no interest at all for the flowers of this species. Special attention was paid to the forms of the taxonomically confusedOphrys fusca group:O. fusca s. str.,O. iricolor, O. omegaifera andO. atlantica. WhileO. fusca s. str. is widespread, small-flowered and has late anthesis,O. iricolor has very large flowers and early anthesis. Each of the four members ofO. fusca agg. in S. Spain is pollinated by a different bee, and selective experiments show that each of these four species of bees is specifically attracted only to one of theOphrys species:Andrena flavipes is the pollinator ofO. fusca s. str.,Colletes cunicularius infuscatus ofO. iricolor, Anthophora atroalba ofO. omegaifera, andChalicodoma parietina ofO. atlantica. These four pollinators belong to 4 different bee families (Andrenidae, Colletidae, Anthophoridae, Megachilidae). As this type of pollination represents a very effective pregamic isolation mechanism, these four taxa ofOphrys fusca agg., at least in southern Spain, behave and should be regarded as genuine species.

     

Nothobartsia,a new genus ofScrophulariaceae from southwest Europe

Recent systematic studies ofBartsia andOdontites showed the necessity to exclude the closely related perennial speciesBartsia aspera (Portugal and northern Morocco) andBartsia spicata (Central Pyrenees) from the genusBartsia as a segregate genus namedNothobartsia. Morphologically this new genus combines characteristic features ofBartsia and ofOdontites. Its autonomous systematic position is supported by the cladistic analysis, showing thatNothobartsia represents a relatively primitive genus standing close to the common ancestral root ofBartsia, Euphrasia, andOdontites.     

Three new species and a new combination in the genusTorulomyces from soil

Seven isolates ofTorulomyces from Asian and Australian soil samples were studied in comparison with known taxa of the genus and withMonocillium indicum, the type species ofMonocillium. Three new species,Torulomyces parviverrucosus, T. laevis, andT. ovatus, are described, andT. brunneus is described as a new combination. Conidial characteristics, especially their shape and surface structure, are useful taxonomic criteria for distinguishing species ofTorulomyces. Monocillium is considered to be a distinct genus.     

Some Entolomataceae (Agaricales) from Costa Rica

A preliminary account of Entolomataceae from Costa Rica is presented. Three new taxa are described, two inClitopilus, one inRhodocybe, and three new combinations are proposed inInocephalus. Five taxa ofClitopilus are reported for the first time from Costa Rica and a key to species is provided. Four species ofRhodocybe are discussed and a key to the six species known from Costa Rica is also provided.Alboleptonia earlei, Inocephalus murraii, Inocephalus quadratum, Rhodocybe incarnata andRhodocybe pseudonitellina are now known to occur in Costa Rica.     

Localized hybridization betweenSaxifraga aizoides andS. mutata (Saxifragaceae): Reproductive ecology ofS. ×hausmannii and implications for conservation

The roles of hybridization and of introgression as potential threats to small native populations are current topics of interest both for evolutionary and conservation biologists. Two factors are mainly involved in the threat to natural populations through hybridization: demographic swamping and genetic assimilation. At prealpine locations, twoSaxifraga species with very different growth habits,S. aizoides andS. mutata, form a hybrid,S. ×hausmannii. Investigation of meiosis and crossing experiments revealed regular pairing of the 26 chromosomes and development of viable seeds in the hybrid. Analysis of hybrid indices, GPI allozymes, germination experiments and seed sizes showed an intermediate position ofS. ×hausmannii between its parental species.Saxifraga aizoides andS. mutata were separated by only weak hybridization barriers. Introgression occurred mostly in direction ofS. aizoides, although to a small amount. There is no actual threat to small, prealpine populations ofS. aizoides andS. mutata through interspecific gene flow because hybridization is localized, resulting from different flowering phenologies of the parental species and from the narrow habitat requirements ofS. ×hausmannii, which are similar to those ofS. aizoides. The major threat to local, prealpine populations ofS. aizoides andS. mutata is the loss of landscape dynamics. Both species need open erosion slopes for successful recruitment.     

The fine structure of motile cells in the generaUlvaria andMonostroma,with special reference to the taxonomic position ofMonostroma oxyspermum (Ulvophyceae,Chlorophyta)

The zoospores and isogametes ofUlvaria obscura var.blyttii, the isogametes ofMonostroma bullosum, and the anisogametes ofM. grevillei have a flagellar apparatus with counterclockwise absolute orientation and terminal caps, and therefore belong to theUlvophyceae. On the basis of the absence or presence of body scales and the morphologies of certain flagellar apparatus components,Ulvaria obscura var.blyttii is retained in theUlvales, whileM. bullosum, M. grevillei andM. oxyspermum are referred to theUlotrichales. Differences in scale morphology, certain flagellar apparatus components, and early thallus ontogeny support the transfer ofM. oxyspermum to the genusGayralia. Mating structures and their positional relationships within the cell are described from the gametes examined. A plasmalemma-associated plaque that may be a degenerate mating structure occurs in someG. oxysperma motile cells.     

The phylogeny ofPapaver s. l. (Papaveraceae): Polyphyly or monophyly?

An RFLP analysis of the chloroplast genetrnK of 32 species of the generaPapaver, Roemeria, Stylomecon, andMeconopsis leads to the following conclusions: (1) AsianMeconopsis consists of two distinct clades and is paraphyletic in relation toPapaver, Roemeria, Stylomecon, and the W EuropeanMeconopsis cambrica. (2) Sister group relationships ofRoemeria toPapaver sect.Argemonidium and ofStylomecon toPapaver californicum are well-supported. (3)Meconopsis cambrica is nested withinPapaver (incl.Roemeria andStylomecon). The consideration of morphology, geographical distribution and ecology leads to the conclusion thatM. cambrica is best regarded as a member ofMeconopsis, and thatPapaver arose polyphyletically from within a paraphyleticMeconopsis in response to Tertiary climatic aridification. — The removal ofM. cambrica from the taxon matrix is discussed. It is concluded that this experiment illuminates the importance of critical taxon sampling, and shows that at least potentially the assessment of taxa as mono-, para-, or polyphyletic may characterize their present status only and need not reflect their phylogenetic history.     

rbcL sequences support exclusion ofRetzia,Desfontainia, andNicodemia from theGentianales

The taxonomic positions ofRetzia, Desfontainia, andNicodemia have been much discussed, and all three genera have been included inLoganiaceae (Gentianales). We have made a cladistic analysis ofrbcL gene sequences to determine the relationships of these taxa toGentianales. Four newrbcL sequences are presented; i.e., ofRetzia, Desfontainia, Diervilla (Caprifoliaceae), andEuthystachys (Stilbaceae). Our results show thatRetzia, Desfontainia, andNicodemia are not closely related toLoganiaceae or theGentianales. Retzia is most closely related toEuthystachys and is better included inStilbaceae. The positions ofDesfontainia andNicodemia are not settled, butDesfontainia shows affinity for theDipsacales s.l. andNicodemia for theLamiales s.l.     

The branching of the inflorescence and vegetative shoot and taxonomy of the genusKummerowia (Leguminosae)

A study of the branching of the inflorescence and the vegetative shoot of the genusKummerowia, consisting ofK. stipulacea (Maxim.) Makino andK. striata (Thunb.) Schindler, has led to the following conclusions: (1) the inflorescences of both species are reduced compound cymes, (2) the branching system of the inflorescence ofKummerowia is not clearly different from that of the vegetative shoot and there are some transitional forms between both systems, and (3) the inflorescence ofKummerowia is different from the racemose inflorescences ofLespedeza andCampylotropis. Based on the differences found in the branching system of the inflorescence,Kummerowia is distinctly separated fromLespedeza andCampylotropis and is more correctly treated as a distinct genus from the latter two.