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1.
Rhytisma polaris, which causes tar spot disease on Salix polaris on Spitsbergen Island, is described. The most characteristic morphological feature of this new species are ascospores distinctly broader than those of other Rhytisma species. rDNA ITS and LSU sequence analysis also indicated that R. polaris is sufficiently distinct from other Rhytisma species to justify the new species status.  相似文献   

2.
Two little known species of brown algae, Litosiphon mortensenii S. Lund and L. groenlandicus S. Lund, described from East Greenland have been compared with the type species of the genera Litosiphon Harv. and Asperococcus Lamour. They are distinguished from the genus Litosiphon by their basally sheathed hairs, hecatonematoid microthalli, mediate differentiation of embryospores, and lack of sympodial branching of the macrothallus. They are considered more primitive than Asperococcus by the absence of paraphyses and by the non-localized formation of reproductive structures. The new genus Trachynema is proposed to accommodate these plants; it finds a natural position in the Punctariaceae.  相似文献   

3.
Scytosiphon complanatus from Greenland was grown under long-day conditions on a temperature-gradient device with a temperature range from 5.4°C to 31.8°C. Growth was optimal between 16.0°C and 20.9°C. In a four week experimental period at 5.4°C and 7.5°C growth was slow and not measurable. The inoculated germlings died at temperatures between 24.0°C and 27.5°C. Under all temperatures the prostrate systems, knot filaments or ralfsioid thalli, as well as the parenchymatous macrothalli remained sterile during the experimental period. Prolongation of the growth period showed that formation of swarmers was prevented at temperatures above 18.6°C. The geographic distribution is discussed in relation to these results.  相似文献   

4.
Aesia gen. n. with the type species Aesia acerbiana sp. n. is described from Wrangel Island. The new genus belongs to the tribe Blondeliini (as indicated by a short prealar bristle of the mesonotum and by the cerci separated in apical 0.4). It is not similar to any Palaearctic genus of tachinids. In the key to the species of Blondeliini of North and Central America and the West Indies it comes to the genus Eucelatoria but differs from it in having eyes covered with long and dense hairs, the lower facial margin protruding forwards and well visible in lateral view, proboscis with elongate prementum, abdomen of the female not modified, without a keel and piercer. Aesia acerbiana sp. n. was reared from a larva of a tiger moth (Arctiidae), Acerbia alpina Quensel collected in the tundra landscape.  相似文献   

5.
《Journal of bryology》2013,35(1):41-49
Abstract

The reproduction of Pohlia nutans (Hedw.) Lindb. and Pleurozium schreberi (Brid.) Mitt. were compared in the surroundings of copper smelters at Harjavalta, Finland. Samples of both species were collected from 16 sample plots, which were situated on a 12-km transect at intervals of half a kilometre from the smelters. As a result of pollution the production of gametangia decreased in P. schreberi, and near the smelters most of the shoots were sterile. The biomass of shoots seems to have an effect on the production of perichaetia; reproducing females were always the largest ones in the colonies. The reproductive strategy of Pohlia nutans also varied. While, in moderately clean areas, colonies reproduced sexually and formed sporophytes, in the vicinity of the smelters caducous shoot apices were produced. The numbers of sporophytes in colonies were highest in moderately polluted areas and decreased further away from the smelters. The numbers of spores per capsule in P. nutans decreased at polluted sites and the proportion of aborted spores increased.  相似文献   

6.
Lecidea roseotincta sp. nov. is described from Norway. The species is mainly characterized by a white to grey or ± pink, amyloid thallus containing psoromic acid, black apothecia with a weakly developed proper margin, 16-spored asci without a well defined ocular chamber, and simple or 1-septate, medially constricted spores. It grows on bark of deciduous trees, mainly Alnus incana , in coastal sites.  相似文献   

7.
Two new species from Wrangel Island, Orthocladius (Eudactylocladius) tschernovi sp. n. and O. (E.) ushakovskiensis sp. n. (Orthocladiinae), are described and illustrated from on the male adults. Orthocladius (E.) tschernovi sp. n. is closely related to O. (E.) fuscimanus (Kieffer) and O. (E.) musester Sæther, but can be distinguished from both by an almost straight transverse sternapodema, a rounded triangular superior volsella, and a long phallapodema, as well as by the presence of a subapical crista dorsalis of the gonostylus and by the shape of the anal point. Orthocladius (E.) ushakovskiensis sp. n. differs from all the known species of the subgenus in the absence of superior and inferior volsellae and in the shape of both short gonostylus and the short and wide anal point.  相似文献   

8.
9.
We name and describe two new species,Isoetes jejuensis and I.hallasanensis, from Jeju Island, South Korea. These taxa are compared with related species in East Asia, including I.coreana andI. sinensis. The rugulate megaspore ornamentation ofI. jejuensis differs from those otherIsoetes species. Furthermore,I. hallasanensis varies fromI. asiatica in its microspore ornamentation and chromosome number, although both species have an echinate megaspore ornamentation. These new species are tetraploid (2n = 44), whereasI. coreana is hexaploid (2n = 66).  相似文献   

10.
David J. Horne 《Hydrobiologia》1986,139(2):119-122
Two new species of the genus Pseudocythere Sars are described, one each from British and Norwegian waters respectively.  相似文献   

11.
Montagna M 《ZooKeys》2011,(155):51-60
Pachybrachis sassii, new species is described from Giglio Island, of the Tuscan Archipelago (Italy). The new species belongs to the nominotypical subgenus and is closely related to Pachybrachis salfii Burlini, 1957, from which it differs in the shape of the median lobe of the aedeagus and in the pattern of the yellow raised spots on the elytra and pronotum. Ecological observations are made. The neotype of Pachybrachis salfii from Colloreto, Monte Pollino (Italy) is designated.  相似文献   

12.
The new species Squamarina scopulorum Haugan & Timdal (sect. Petroplaca ) is described from Norway. It differs from the sympatric and morphologically closely similar species S. magnussonii and S. pachylepidea mainly in the color of the apothecial disc and in the thallus chemistry. The delimitation of the genus Squamarina and the family Squamarinaceae are briefly discussed.  相似文献   

13.
海南岛苏铁属(苏铁科)一新种,即三亚苏铁。  相似文献   

14.
Spirogyra pseudotetrapla Kadi. sp. nov. is described from a coastal freshwater pond at Godhavn, W Greenland.  相似文献   

15.
Fend  Steven V.  Gustafson  Daniel L. 《Hydrobiologia》2001,463(1-3):13-22
Secubelmis limpida n. sp., n. gen., is described from Montana, U.S.A. The monotypic genus resembles the lumbriculid genera Rhynchelmis and Tatriella in having atria in X, spermathecae in VIII, and semi-prosoporous male ducts. It differs from Tatriella in having paired atria and spermathecae, and from Rhynchelmis in having petiolate atria. The single prostate gland is unique within the Lumbriculidae. The new species appears to have a restricted range in the northern Rocky Mountains.  相似文献   

16.
A new species of the fern genus Lygodium has been described in detail with photographs and illustrations from Saddle Peak in the North Andamans, India.  相似文献   

17.
Kerr PH 《ZooKeys》2011,(137):41-76
Six new species are described, raising the number of North American Acomoptera species to seven and the genus total to ten, and nearly doubling the number of species within the putative clade containing Acomoptera, Drepanocercus, and Paratinia. These novel species forms have implications for the concept of Acomoptera that in turn, may impact our understanding of its generic relationships and the evolution and composition of Gnoristinae and Sciophilinae. The new species, Acomoptera crispa, Acomoptera digitata, Acomoptera echinosa, Acomoptera forculata, Acomoptera nelsoni,and Acomoptera vockerothi, are compared with the type species of the genus, Acomoptera plexipus (Garrett), whose diagnostic features are imaged and illustrated for the first time. The European species, Acomoptera difficilis (Dziedzicki) is also illustrated and compared. Acomoptera spinistyla (Søli) comb. n. is transferred from Drepanocercus. A key to species is provided. Future work will seek to incorporate this knowledge into a systematic phylogenetic study of relationships between these species and their sister taxa.  相似文献   

18.
Dendrobium shompenii is described and illustrated as a new species from Great Nicobar Island, India. Affinities with the closely related species Dendrobium nathanielis are discussed.  相似文献   

19.
Polydactylus bifurcus sp. nov. is described on the basis of a single specimen collected from Lombok Island, Indonesia. The new species is distinguished from all other Indo-Pacific Polydactylus species by the following combination of characters: 15 pectoral fin rays, 5 pectoral filaments, 69 pored lateral line scales, 30 gill rakers, second spine of first dorsal fin very strong and lateral line bifurcated on caudal fin base, extending to posterior margins of upper and lower caudal fin lobes. Received: October 19, 2000 / Revised: April 21, 2001 / Accepted: April 25, 2001  相似文献   

20.
The chemistry of the essential oil of Thymus praecox Opiz ssp. arcticus (E. Durand) Jalas from Greenland was studied with the intention of comparing it with the results obtained earlier from Icelandic material. All the 17 samples collected at different localities of South–West Greenland were found to contain linalyl acetate as main component besides some sesquiterpene hydrocarbons and some oxygenated sesquiterpenes. The variable content of the sesquiterpene alcohols, nerolidol and hedycaryol in the essential oil gave reason to define four different chemotypes. The pattern of the chemotype characterizing compounds was identical with that of four of the seven chemotypes found earlier to be the most widely distributed in Iceland, namely chemotypes B, C, D, and F. No correlation between the occurrence of a certain type and special environmental conditions was found. That the essential oil chemistry and the appearance of polychemism in the Greenland Thymus plants accords so well with that of the Icelandic ones, indicates that the distance of nearly 300 km between Iceland and Greenland has not led to locally limited chemical races within Thymus praecox ssp. arcticus. These findings are contrary to the results obtained in some Mediterranean Thymus species.  相似文献   

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