Interspecific hybridization in the genus Hieracium s. str.: evidence for bidirectional gene flow and spontaneous allopolyploidization

Although reticulation has indisputably played an important role in the evolutionary history of the genus Hieracium s. str. (Asteraceae), convincingly documented cases of recent interspecific hybridization are very rare. Here we report combined evidence on recent hybridization between two diploid species, Hieracium alpinum and H. transsilvanicum. The hybrid origin of the plants from the Romanian Eastern Carpathians was supported by additive patterns of nuclear ribosomal DNA polymorphism (ITS), an intermediate position of hybrid plants in principal coordinate analysis based on amplified fragment length polymorphism phenotypes (AFLP), and additivity at one allozyme locus. Flow cytometric analyses and chromosome counting showed that two hybrids were diploid (2n ~ 2x ~ 18) while one was surprisingly tetraploid (2n = 4x = 36). To our knowledge, this is the first record of spontaneous polyploidization following interspecific crossing in the genus. Allozyme data, especially the presence of unbalanced heterozygosity at one locus, suggest the origin of this tetraploid via a triploid bridge with subsequent backcrossing to H. alpinum. According to PCR-RFLP analyses of the trnT-trnL intergenic spacer, all H. ×krasani hybrids examined had the H. alpinum haplotype while H. transsilvanicum served as a pollen donor. The hybrids occurred at the locality with abundant H. alpinum plants where paternal H. transsilvanicum was missing. Previously reported instances of interspecific hybridization between the same parental taxa showed an opposite direction of crossing and relative abundance of parental taxa. This suggests that the direction of hybridization might be influenced by the frequency of parental taxa at the locality.     

Dimorphism in inflorescence scent of dioecious wild grapevine

Wild grapevine (Vitis vinifera subsp. sylvestris) is the dioecious ancestral form of grapevine, from which the domesticated cultivars have derived (V. vinifera subsp. vinifera). Little is known about the floral scent compounds of wild grapevine that is considered as being partly insect pollinated. The knowledge of volatiles released by male and female inflorescence may contribute to the understanding of the pollination biology of this endangered taxon. Inflorescence scents of male and female individuals were collected by dynamic headspace and analysed by thermal desorption-GC/MS. A total of 17 compounds of C5-branched chain alcohols, aliphatics, aromatics, and terpenoids were identified with benzyl alcohol being most abundant in both sexes. Eight of the compounds were sex-specific and differences in 1,2-dimethoxybenzene were most obvious. This aromatic compound was a main constituent in the scent of females (30%), but it did not occur in males. Some of the main compounds of the scent samples are known to be detected by beetles (Cerambycidae) or attract sweat bees (Halictidae) and honey bees (A. mellifera), all well-known inflorescence visitors in wild grapevine. The data presented here are an important step in understanding the chemical communication between wild grapevine and its inflorescence visitors/potential pollinators.     

Hybridogene Merkmals-Introgression zwischenGalium rubrum L. s. str. undG. pumilum Murr. s. str

Ohne Zusammenfassung     

Zur Cytologie vonClavaria s. str

Zusammenfassung BeiClavaria sphagnicola tritt im gleichen Hymenium sowohl Chiastoals auch Stichostellung der meiotischen Spindeln auf. Der Verschmelzungskern erfährt die I. Teilung entweder in der Tiefe der Basidie, dann steht die I. Spindel anscheinend immer längs, oder er wandert vorher in den Scheitel der Basidie, dann kommen beide Stellungen vor. Die Meiose läuft in sehr verschieden alten Basidien ab, vermutlich erfolgt auch die Kernfusion zu verschiedenen Zeiten und oft auffallend spät.Die Chromosomenzahl ist deutlich höher als n=4 und beträgt mindestens n=8, wahrscheinlich aber noch mehr, vielleicht 12.Die Sporen und die Myzelzellen sind zweikernig, die Zellen des Fleisches der Fruchtkörper werden unter entsprechender Vergrößerung sekundär vielkernig (bis 56kernig); Kern- und Zellteilung verlaufen in ihnen sehr unregelmäßig.Die Zweikernigkeit der Spore wird durch eine Mitose in der jungen Spore erreicht, die zusätzlich zu einer postmeiotischen Mitose in der Basidie abläuft.     

Ontogeny of the translator inAsclepiadaceae s.str.

The ontogeny of the translator is analysed inFockea edulis, Pachycarpus dealbatus, andCalotropis procera. The three species show a similar basic pattern in the construction of the corpusculum. Each side wall consists of two originally separate flanks. In the primitive state (Fockea), these flanks remain separate throughout their development, only the two inner flanks fuse along their base. In the derived state, the two flanks on each side fuse to form solid side walls, and the corpusculum develops a floor by additional secretion. The primitive state of divided flanks is recapitulated in early ontogeny. InFockea, the pollinia are attached apically and dorsally to the outer flanks by means of unmoulded adhesive material; in more advanced translators, caudicles are inserted as new elements between the outer flanks and the pollinia. The caudicles are attached to the lower part of the corpusculum. Within the four tribes of the family, many species have retained parts of the primitive structure in their corpuscula. Flanks divided in the lower part of the corpusculum and caudicles attached dorsally to the outer flanks seem to be common inMarsdenieae andStapelieae. InAsclepiadeae andGonolobeae the side walls are solid throughout the length of the corpusculum. — The question of cellular mechanisms underlying the formation of the translator is discussed. In all probability, the main factor responsible for the complex structure of the corpusculum is a differential secretory activity of the glandular field. This, in turn, points to differential genetic activity as a regulating factor of the ontogeny of the translator.     

中国的石松科植物

本文对国产石松科(狭义)进行了分类学研究,共记载本科植物6属15种3变型。文中引用新建 立的1属,即拟小石松属Pseudolycopodiella Holub,并包含1个新命名：Lycopodium neopungens H．S．Kung et L．B．Zhang,1个新变型：Palhinhaea hainanensis C．Y. Yang f．glabra H．S．Kung et L．B．Zhang和9个新 异名：Lycopodium annotinum L．var．brevifolium Christ(=L ．zonatum),L．annotinum L．var．aciculare Christ (=L．zonatum),L.alticola Ching(=L．zonatum),L．simulans Ching et H．S．Kung ex Ching(=L．japoni- cum),L．interjectum Ching et H．S．Kung ex Ching(=L．japonicum),L. taliense Ching(=L．japonicum),L．pseudoclavatum Ching(：=L．japonicm．),L． pseudoclavatum Ching var．yunnanense Ching(=L．japonicum),及L. centro-chinense Ching(=L. japonicum)．本文还记述了有关分类群的地理分布,并认为中国没有Dipha- siastrum wightianum(Wall．ex Grev．et Hook．)Holub的分布。     

The reclassification of Lycopodiaceae (s. str.) in China

The fern-allied family Lycopodiaceae(s. str. ) in China is reclassified in the present paper. Six genera, fifteen species and three forms are recorded. The genus Pseudolycopodiella Holub (1983) is adopted, one new name, Lycopodium neopungens H. S. Kung et L. B. Zhang, is given to replace the invalid name L. pungens Desv., one new form is described: Palhinhaea hainanensis C. Y. Yang f. glabra H. S. Kung et L. B. Zhang, and nine names are treated for the first time as synonyms: L. annotinum L. var. brevifolium Christ( = L. zonatum Ching), L. annotinum L. var. aciculare Christ( = L. zonatum Ching), L. alticola Ching( = L. zonatum Ching), L. simulans Ching et H. S. Kung ex Ching( = L. japonicum Thunb. ex Murray), L. interjectum Ching et H. S. Kung ex Ching( = L. japonicum Thunb. ex Murray), L. taliense Ching(＝L. japonicum Thunb. ex Murray), L. pseudoclavatum Ching( = L. japonicm Thunb. ex Murray.), L. pseudoclavatum Ching var. yunnanense Ching( = L. japonicum Thunb. ex Murray), and L. centro-chinense Ching( = L. japonicum Thunb. ex Murray). The distribution of all the taxa is also given. Additionally, some taxonomic discussions are made and it is considered that there is no Diphasiastrum wightianum (Wall. ex Grev. et Hook. ) Holub( = Lycopodium wightianum Wall. ex Grev.et Hook. ) in the flora.     

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.

     

狭义干蘑属( 蘑菇目) 概要及新的系统学处理

对狭义干蘑属( Xerula s . str .) 的范围进行了重新界定, 该属仅包括模式种干蘑( X. pudens) 及其周围的几个种。属的特征是担子果金钱菌状, 有假根; 菌盖及菌柄表面干燥, 被有黄色至褐色直立、披针形的刚毛; 菌褶边缘无不育带; 子实层有近梭形的小担子。这些特征可以将干蘑属的物种从干蘑属- 小奥德蘑属复合群中分开。现知干蘑属包含六种, 本文提供了这些种的检索表, 并对各种进行了描述、图示或讨论。其中, 硬毛干蘑( X. strigosa) 是一新种, 它与干蘑( X. pudens) 和中华干蘑( X. sinopudens) 相似, 但与干蘑不同在于其担孢子较长, 锁状联合稀少, 侧生囊状体顶端壁薄; 与中华干蘑的区别在于其侧生囊状体壁厚, 顶端有头状至近头状膨大并覆盖有结晶, 担孢子宽椭圆形至椭圆形。中华干蘑和小刺干蘑( X. setulosa) 分别为我国和哥斯达黎加的新记录种。干蘑属虽然广布北半球, 但未见东亚- 美洲或欧亚广布的物种分布类型。     

Taxonomical investigations onHelleborus viridis s. l. (Ranunculaceae) in Northern Italy

The taxon commonly namedHelleborus viridis in Lombardy (NW. Italy) differs from both, subsp.viridis and subsp.occidentalis, and is shown to fall within the variation range ofH. odorus subsp.laxus which has been reported so far for NE. Italy only. TrueH. viridis within Italy grows only in the Maritime Alps.     

Remarques sur le genre Cyclops s. str. (Crust. cop.)

Sans résumé     

Fruit micromorphology and anatomy of Valeriana officinalis s. str. (Valerianaceae)

Fruits of two varieties of Valeriana officinalis s. str. (var. officinalis , var. nitida ) are similar in general construction, but differ in details of external and internal structure. The outer cells of the pericarp form a regularly punctuated surface in both taxa. Scanning electron microscopy demonstrates variation in cuticular sculpturing of the outer epidermal cell walls and the presence of epicuticular wax. The surface of fruit hairs varies from micropapillate in var. officinalis to linear warty in var. nitida . In the mature rericarp there occur three distinct histological zones: an outer exocarp, a central mesocarp, and an inner endocarp. The seed is small, enclosed in the indehiscent fruit, with thin seed coat and a straight embryo. Endosperm is absent. The results of this carpological study, especially the SEM characters of pericarp surface, may provide criteria useful for delimitation of V officinalis varieties.     

Speciation and Phylogenetic Distances within Paxillus s. str. (Basidiomycetes, Boletales)

Abstract: This study aimed to elucidate the phylogenetic relationships within Paxillus 5. str. Collections of the Paxillus involu-tus complex from different habitats have been compared. DNA sequence data were generated from the nuclear encoded 28S gene and the ITS region. Phylogenetic analyses of the two data sets showed three clearly differentiated groups within Paxillus s. str. Collections from gardens and park areas under Betula, Cory-lus, Populus, Quercus and Tub showed to have a very close relationship to the North American species Paxillus vernalis , but are separated from P. involutus collections found in forests as well as from P. filamentosus . Possible taxonomic conclusions are discussed.     

The Phytogeography of Caprifoliaceae s. str. with Its Implications for Understanding Eastern Asiatic Flora

The Caprifoliaceae s. str. as here defined consists of 4 tribes and 12 genera: Caprifolieae (Lonicera, Leycesteria), Linnaeeae (Symphoricarpos, Abelia, Zabelia, Linnaea, Dipelta, Kolkwitzia, Heptacodium ), Diervilleae (Diervilla, Weigela ), Triosteae (Triosteum). Based on chorology, fossil records and dominant woody habit, the family may be considered as a fairly old one and probably originated in the Late Cretaceous or the Early Tertiary. In the light of facts, such as a number of phylogenetic series of Abelia, Triosteum and Weigela occurring in east Asia, Heptacodium, endemic to East Asia, as a link between the tribe Caprifolieae and the tribe Linnaeeae, and existence in East Asia of a high percentage of both palaeoendemic genera and some neoendemics, East Asia seems to be the centerof diversity of the family. Six Eastern Asiatic endemic genera might be grouped under three categories, Heptacodium, Dipelta and Kolkwitzia as palaeoendemics, Weigela as active epibiotics, and Zabelia and Leycesteria as neoendemics. The above inferences are made only on the basis of three main attributes, systematic position of genera isolated or not, their geographical distribution continuous or discontinuous with the closest relatives and the degree of diversification of forms or distinction between species within a genus, without consideration of insufficient fossil records and cytological data.     

Phylogeography and systematics of Acanthogammarus s. str., giant amphipod crustaceans from Lake Baikal

Daneliya, M. E., Kamaltynov, R. M. & Väinölä, R. (2011). Phylogeography and systematics of Acanthogammarus s. str., giant amphipod crustaceans from Lake Baikal. —Zoologica Scripta, 40, 623–637. To illustrate the dynamics of evolution of the rich endemic crustacean diversity in the ancient Siberian Lake Baikal, we explored the phylogenetic relationships and intralake phylogeographic structure in members of the genus Acanthogammarus Stebbing (Amphipoda, Gammaridea, Acanthogammaridae), which involves some of the most spectacular gigantic freshwater amphipods in the world. Mitochondrial cytochrome oxidase I gene sequence data gave only partial support to either of the recent competing views of systematic diversity. The three species Acanthogammarus victorii, Acanthogammarus maculosus and Acanthogammarus lappaceus along with a fourth, undescribed taxon endemic to the Ushkanii archipelago, made a monophyletic group corresponding to the subgenus Ancyracanthus. A sister relationship of the vicarious ‘subspecies’A. victorii and A. maculosus was not supported, rather the southerly A. victorii was basal to the cluster of the three other northerly, overlapping species. The data generally supported full species rank for the previously debated subspecies taxa, apart from the purported distinction between ‘Acanthogammarus longispinus’ and Acanthogammarus lappaceus, which seems to represent intraspecies morphological variation, partly related to sexual dimorphism. The sister status of Acanthogammarus godlewskii and A. gracilispinus (and thus subgenus Acanthogammarus) had weak support; reassessment of museum collections showed that they both are widespread and sympatric throughout the lake. The observed interspecies sequence differences were 13–22% (23–64% in terms of model‐based distance), suggesting divergence times of several million years under conventional calibrations, calling the applicability of external clocks into question. Strong patterns of intraspecific, intralake phylogeographic subdivision were found in A. lappaceus, A. maculosus and A. gracilispinus, each comprising several disjunct lineages with 1–5% divergence. Other species showed only slight differentiation. In all, the patterns of geographical differentiation were unique for each species, varying from moderate allele frequency differentiation to well‐established geographically segregated lineages, presumably of Early and Middle Pleistocene age. The patterns of differentiation in Acanthogammarus support an important role of allopatric diversification in the evolution of Lake Baikal fauna.