Zur faktorenanalyse des schlüpfrhythmus der flugstadien von Baetis alpinus Pict. (Baetidae,Ephemeroptera)

Zusammenfassung Die Untersuchungen, die an der Biologischen Station Lunz/N.Ö. durchgeführt wurden, zeitigten folgende Ergebnisse:Im Experiment unter konstanten chemischen und Temperaturverhältnissen erfolgt im Naturtag die Häutung zur Subimago nur bei Licht und auf die Stunden zwischen 12 Uhr und Sonnenuntergang konzentrient. Im Dauerlicht läuft das Schlüpfen frei ab, im Dauerdunkel wird es unterdrückt. Die Dauer des Subimagostadiums ist unter natürlichen Bedingungen von der Temperature abhänig, das Schlüpfen der Imagines ist tageszeitlich nicht festgelegt. Dies bestätigen auch die experimentellen Untersuchungsergebnisse.

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Summary Observations were carried out at the Biological Station Lunz in Lower Austria.If chemical and temperature conditions are kept constant, the subimagines of B. alpinus emerge under natural illumination only in light, mainly between 12.00 and sunset. In permanent light the rhythmicity of emergence seems to be disturbed, in permanent darkness emergence is suppressed.Under natural conditions the duration of the subimago stage depends only on temperature and is not fixed to a particular time of day.

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Frau Univ.-Prof. Dr. Agnes Ruttner-Kolisko zum 60. Geburtstag gewidmet.     

Ephemerella readeri Müll. Hal. (Physcomitrella readeri (Müll. Hal.) I.G. Stone & G.A.M. Scott,Funariidae, Bryophyta): a genus and species new to Europe

Abstract

A morphological and molecular analysis of a Physcomitrella, collected from a reservoir margin in the north of England, revealed this to be P. readeri, a species new to Europe. The present study clarifies previous confusion over the taxonomy of P. readeri showing it to be clearly distinct in both sporophytic and gametophytic characters from P. patens and uniform across its world range from England to USA, Japan and Australasia. While phylograms of the ITS1 region from both the Physcomitrella species, Physcomitrium pyriforme (Hedw.) Bruch & Schimp., Enthosthodon attenuatus (Dicks.) Bryhn and Funaria hygrometrica Hedw., place the first two in separate clades, in ITS2 phylograms they occur as sister taxa. This, together with previous genealogical studies on the speciation history of the Physcomitrella–Physcomitrium species complex, and morphology, suggests that generic rank is appropriate for P. readeri. We therefore reinstate the original name Ephemerella readeri Müll. Hal. Recent records at several reservoirs in England indicate that E. readeri may be native to UK, though remarkable congruence in ITS1 with Australian plants also suggests recent arrival as an alternative possibility.     

Zur Nomenklatur der Gattungen Porochara Mädler 1955 (syn. Musacchiella Feist & Grambast-Fessard 1984) undFeistiella n. gen. (Charophyta)

The basal plate of the genusPorochara MäDLER 1955 (Porocharaceae, Charophyta) was proved to be divided into two parts by examining its type species. ThusMusacchiella Feist & Grambast-Fessard 1984 is a younger synonym ofPorochara. The genusFeistiella n. gen. is established for those species with undivided basal plates and it is described with the type speciesFeistiella bijuescensis n. sp. Six other species are attributed to this new genus. The relation between a fan shaped internal structure of the spiral cells and a brackish environment is discussed.     

Ecology,development and pathogenicity of Buddenbrockia plumatellae Schröder, 1910 (Myxozoa,Malacosporea) (syn. Tetracapsula bryozoides) and establishment of Tetracapsuloides n. gen. for Tetracapsula bryosalmonae

Buddenbrockia plumatellae, an enigmatic worm-like myxozoan, was observed as continuously writhing free and attached 'worms' and as free mature spores in the coelom of the freshwater bryozoans Plumatella fungosa, Hyalinella punctata, and Fredericella sp. 'Worm' numbers could double every three days. 'Worms' and spores could be expelled from colonies by external pressure. Some mature 'worms' exited actively, entraining release of free spores, and gradually ceased movement outside the host. Bryozoans sealed off infected regions of the colony. Infected colonies grew slowly, produced no statoblasts, and eventually regressed and died. Transmission was not achieved and prevalence was low. Electron microscopy of 'worms' revealed a single layer of mural cells on a fibrous basal lamina overlying four longitudinal muscle blocks and an inner sheet of two types of proliferating cells, an organization indicative of the bilaterian ancestry of the Myxozoa. Primary type A cells were attached directly by striated tubules to mural cells at positions between muscle blocks. Secondary type A cells had a secretory function. Type B cells underwent meiosis and subsequently developed to typical malacosporean myxozoan spores filling the internal cavity of the 'worms'. External tubes were formed during capsulogenesis in 'worms' from Fredericella sp. Tetracapsula bryozoides is synonymised with Buddenbrockia plumatellae and a new genus is proposed for Tetracapsula bryosalmonae.     

?Globorotalites westfalicus n. sp. aus dem Alb der Haard (Südliches Münsterland,Nordwestdeutschland)

From the Albian of the Southern Muensterland (Northwestern Germany) ?Globorotalites westfalicus n. sp. is described. That new species is suitable at least regionally for fine-stratigraphic correlations.     

Olpidiopsis antithamnionis n. sp. (Oomycetes,Olpidiopsidaceae), a parasite of Antithamnion floccosum (O. F. Müll.) Kleen from Newfoundland

Summary Olpidiopsis antithamnionis n. sp. (Oomycetes, Olpidiopsidaceae) parasitic on Antithamnion floccosum (O. F. Müll.) Kleen (Rhodophyta, Ceramiaceae) is described from three sites in Newfoundland, Canada, and from culture.Axial cells of the main and determinate branches of the host are the primary sites of fungal attack, although tetrasporangia and rhizoidal cells are also susceptible. Successful re-infection of A. floccosum was achieved in the laboratory although A. boreale and the trailliella-phase of Bonnemaisonia hamifera, both occurring with A. floccosum in the field, were immune. Regeneration of the host cells was observed, a phenomenon not previously reported in the fungal parasitism of other filamentous benthic marine algae.Studies in Biology from Memorial University of Newfoundland No. 256.     

Features of the formation of self-fertile euploid lines (2n = 42) by self-pollination of the 46-chromosome barley-wheat BC1 hybrid Hordeum marinum subsp. gussoneanum Hudson (= H. geniculatum All.) (2n = 28) × Triticum aestivum L. (2n = 42)

We studied some features of the development of self-fertile 42-chromosome lines on the base of self-pollination progeny of 46-chromosome plants obtained by backcrossing of barley-wheat hybrids Hordeum marinum subsp. gussoneanum Hudson (= H. geniculatum All.) (2n = 28) × Triticum aestivum L. (2n = 42). The stabilization of karyotypes, resulting in 42-chromosome plants of the wheat type was generally completed by generation BC₁F₁₀. The plants of all self-pollination progenies, including BC₁F₁₀, showed some phenotypic traits characteristic of wild barley. Plants of BC₁F₁₀ with the chromosome sets 2n = 42 and 2n = 42 + t were analyzed by RAPD with a set of 115 primers. Fragments of the wild barley genome were detected in RAPD patterns with 19 primers. Cross-hybridization confirmed that these fragments belonged to the wild barley genome. We raised four phenotypically different 42-chromosome lines from grains obtained from plants of generation BC₁F₁₀, and these lines proved to be cytogenetically stable and self-fertile when grown in the field.     

Poecilorhynchus perplexus n. g., n. sp. (Trypanorhyncha: Eutetrarhynchidae) from the brownbanded bambooshark, Chiloscyllium punctatum Müller & Henle, from Australia

A new genus of trypanorhynch cestodes is described from the brownbanded bambooshark, Chiloscyllium punctatum Müller & Henle (Hemiscylliidae) from off Nickol Bay, Western Australia. Poecilorhynchus perplexus n. g., n. sp. is placed in the Eutetrarhynchidae Guiart, 1927 because it is characterised by an elongate, acraspedote scolex with two oval bothria, the absence of bothrial pits, elongate bulbs, the presence of gland-cells within the bulbs and prebulbar organs, retractor muscles inserting at the base of each bulb and an acraspedote strobila. It can be distinguished from all other genera in this family by its possession of a poeciloacanthous typical armature, with a chainette composed of two longitudinal files of uncinate hooks on the external tentacular surface.     

Triloculotrema japanicae n. g., n. sp. (Monogenea: Monocotylidae) from the olfactory sacs of the Japanese topeshark Hemitriakis japanica (Müller & Henle, 1839) (Carcharhiniformes: Triakidae)

Triloculotrema japanicae n. g., n. sp. (Monogenea: Monocotylidae: Merizocotylinae) is described. The parasite inhabits the olfactory sacs of the Japanese topeshark Hemitriakis japanica (Carcharhiniformes: Triakidae), and possesses a distinctive haptor with only three loculi. Some comments are made on the evolution of monocotylid monogeneans.     

Seasonal studies on alginate and its composition II: Turbinaria conoides (J.Ag.) Kütz. (Fucales, Phaeophyceae)

The alginates extracted from ‘leaf’, ‘stem’ and entire thallus of Turbinaria conoides (J.Ag.) Kütz. were investigated for their viscosity and biochemical constituents namely, β-D-mannuronic acid (M-block}), α-L-guluronic acid (G-Block) and alternating sequences of β–D-mannuronic acid and α-L-guluronic acid (MG-block). Substantial seasonal variation was recorded with high yield of alginate during premonsoon. The yield of alginate was maximum in ‘leaf’ region. In contrast to this, viscosity and G-block were maximum in the ‘stem’ region. A significant positive correlation was observed between viscosity and G-block}. The ratio of guluronic: mannuronic acid was also assessed. Low levels of M/G ratio were recorded in the ‘stem’ region followed by ‘leaf’ and entire thallus.