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1.
A taxonomic study of the largely Mexican genusCarminatia is rendered. It is comprised of three closely related species:C. tenuiflora, C. recondita andC. anomala spec. nova. Illustrations, dot maps, keys to species and complete synonymy are presented.  相似文献   

2.
Neodiaptomus schmackeri and related species are redescribed. The synonymy of this species with N. strigilipes and N. handeli is discussed.  相似文献   

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Two new species of hyalellid amphipods, Hyalella crawfordi and H. gauthieri, are described from Lake Titicaca; H. echinus (Faxon, 1876) is redescribed. The H. echinus group of species is newly proposed for these three species, and a group diagnosis is provided. A key to the three species in the group is provided Full article published online at http://www.senckenberg.de/odes/06-10.htm.  相似文献   

5.
The endemic New Guinean genusIschnea F. Muell. (Asteraceae, Senecioneae, Blennospermatinae) is revised and four species are recognized. Characters of special interest are tubeless ray florets, male disc florets, and secretory spaces in leaves. A principal component analysis is made on theIschnea elachoglossa F. Muell. complex which shows great variation. One new species,I. capellana Swenson, from the Star Mountains, is described. A key, illustrations, and distribution maps to all species are supplied.  相似文献   

6.
Three species of the genusPicris L. are native in Tropical Africa:P. abyssinica Sch. Bip. (Ethiopia),P. xylopoda Lack, spec. nova (Nigeria, Ethiopia) andP. humilis DC. (Senegal, Mali). There are indications that the two perennial species,P. abyssinica andP. xylopoda, are related to and have evolved from a primitive Central Asiatic stock in a manner parallel to many African species ofCrepis L.P. humilis, on the other hand, is a small annual plant with a high number of derived characters. The introduced species of European origin growing south of the Sahara are briefly mentioned.  相似文献   

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The phycobiont of all species ofLempholemma analyzed is attacked by haustoria. The haustoria of these five species ofLempholemma and of two species with unknown apothecium but with a thallus quite similar toLempholemma are described. They show distinct morphological and functional characters which allow species delimitation.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.  相似文献   

9.
A new unicellular species of the genusChrysosphaerella (Chrysophyceae) was found in fresh-water ponds in Switzerland, Japan, and the U.S.A. It is described asC. solitaria. The genus is divided into two subgenera:Chrysosphaerella, comprising the colonial species, andPseudochrysosphaerella, the unicellular ones.  相似文献   

10.
The American amphipod species Melita nitida andIncisocalliope aestuarius have been found in the WesternScheldt estuary (the Netherlands). This is the first record of these species inthe north-east Atlantic. Shipping is the most likely vector of introduction.Thedistribution of both species is investigated and compared with the distributionand the microhabitat of co-occurring amphipod species. Melitanitida is known from both the east and west coast of North Americaand I. aestuarius originates from the east coast of NorthAmerica. Until now neither has been reported from other parts of the world. Inthe Netherlands both species are restricted to the mesohaline part of theWestern Scheldt. Melita nitida occurs predominantly underPacific oysters at the underside of boulders, mainly sublittorally.Incisocalliope aestuarius is associated to hydrozoans.Bothmicrohabitats are hardly utilized by other amphipod species. Therefore, thetheory that the existence of many empty niches in north-western Europeanbrackish waters make this environment particularly susceptible to invasions ofalien species is corroborated. The application of hard substrates in a regionoriginally predominated by soft bottoms moreover facilitates the introductionofexotic species. The species community on hard substrates in the mesohaline partof the Western Scheldt contains a high proportion of introduced species:approximately one third of the macrofauna species is of allochthonous origin.  相似文献   

11.
Summary Three dorsal ocelli are present inCaenis robusta (Ephemeroptera), Trichostegia minor, Agrypnia varia, andLimnephilus flavicornis (Trichoptera). The dioptric apparatus of the ocelli differs between the four species. InTrichostegia andAgrypnia a biconvex corneal lens is present, inLimnephilus the corneal lens is convexo-concave complemented by an underlying haemocoelic space, whereas a cellular vitreous body is found between the cuticle and the retinal layer in the ephemerid. In the three trichopteroid species the ocelli are surrounded by an array of longitudinally arranged tracheoles; inCaenis a layer of screening pigments is found in this position. In this species the rhabdoms formed by microvilli of neighbouring retinula cells have a randomly arranged meshwork pattern; in the three trichopteroid species the rhabdoms are isolated, built up of four retinula cells. Cells with basally situated nuclei and lamellar extensions between the retinular cells are found in the ocelli ofTrichostegia, Agrypnia, andLimnephilus.  相似文献   

12.
Karyotype analyses were conducted onCunninghamia konishii, Cunninghamia lanceolata, andTaiwania cryptomerioides, all members ofTaxodiaceae. The somatic chromosome number was found to be 2n = 2x = 22 in all species which concurrs with previous reports. The karyotypes are generally asymmetrical with the smaller chromosomes being more submedian than the larger ones. Chromosomes with unusual or specific structures, thought to be associated with the nucleolar organizing region, were found in each species.Cunninghamia species have a marker chromosome pair with an unusually long secondary constriction.Taiwania has an unusually long kinetochore region present in a submedian chromosome pair.  相似文献   

13.
A taxonomic study of the genusDelilia is presented. Two species are recognized:D. biflora, a widespread weed of tropical and subtropical regions of the New World, extending from Mexico to northern Argentina and recently introduced in the Cape Verde Islands; andD. repens, endemic to the Galapagos islands. A key to the species, illustrations, distribution maps, and complete synonymy are presented.  相似文献   

14.
The genusPlectranthus (Lamiaceae) shows remarkable radiation on the sandstones of southern Natal and northern Transkei in South Africa, where six endemic species occur. Two of these endemic species,P. hilliardiae andP. oribiensis, are included in this study, as well asP. reflexus, for which only limited data are available. The other species that were studied areP. ambiguus, P. ciliatus, P. ecklonii, P. madagascariensis andP. zuluensis. Four of these taxa,P. ambiguus, P. hilliardiae, P. reflexus andP. saccatus var.longitubus, have uniquely long corolla-tubes (20–30mm) and this is related to pollination by nemestrinid flies of the genusStenobasipteron that have proboscides of similar length. Other nemestrinid species of the genusProsoeca have shorter proboscides and pollinate two species ofPlectranthus with shorter corolla-tube lengths (6–15mm). Acrocerid flies, tabanid flies and anthophorid bees are also important visitors to these species. This study on the pollination of seven species of varying corolla-tube lengths shows a correlation between floral tube length and proboscis length of insect visitors, many of which are recorded for the first time as pollinators ofPlectranthus.  相似文献   

15.
David G. Frey 《Hydrobiologia》1993,262(3):133-144
Examination of many species of Pleuroxus from the entire World has revealed a major dichotomy in morphology, one line related to aduncus: the other to laevis both from Europe. Pleuroxus trigonellus (the type species of the genus) and Peracantha truncata are in two other distinct lines. The new subgenus Tylopleuroxus is proposed for the species related to aduncus, and the subgenus Picripleuroxus for those related to laevis. Tylopleuroxus is primarily Southern Hemisphere in distribution, Picripleuroxus primarily Northern Hemisphere. Evidence thus far suggests that probably most, perhaps all, of the taxa are confined to single continents or land masses. Deceased  相似文献   

16.
The two species ofPeratanthe, a genus allegedly endemic to the greater Antilles, are shown to be entirely within the variation range ofNertera granadensis (L.f.) Druce var.granadensis, a widespread, often weedy species.  相似文献   

17.
In an investigation of the phenology of the chironomid species of Lake Hald, Denmark, a very late flight activity (September–November) of the univoltine speciesProcladius choreus (Mg.) was observed. Among observations of the phenological patterns of univoltine chironomids inhabiting lakes of the Baltic type in Denmark, the phenological pattern ofProcladius choreus stands alone (JÓNSSON, 1987; LARSEN, 1991). Further two species of the genusProcladius Skuse,viz. Procladius crassinervis (Zett) andProcladius signatus (Zett), were found in the investigation and the phenological pattern of the three congeneric species was clearly allochronic, withProcladius crassinervis flying in spring,Procladius signatus flying in summer andProcladius choreus flying in autumn.  相似文献   

18.
A new genus, Cystobasidiopsis, and a new species, Cystobasidiopsis nirenbergiae, are described for a fungus isolated from an arable loess soil in Ahlum near Braunschweig, Niedersachsen, Germany. An integrated analysis of morphological, ecological, ultrastructural and molecular data indicates that the new species belongs to the Chionosphaeraceae within the Agaricostilbales. Relevant characteristics of the new species are discussed and compared with those of related taxa.  相似文献   

19.
Strophomenid brachiopods belonging to the generaLeptaena andLepidoleptaena are described from the uppermost Llandovery — Ludlow succession of Gotland, Sweden. In Gotland,Lepidoleptaena comprises the single speciesL. poulseni, andLeptaena includes four species:L. rhomboidalis, L. sperion, L. depressa andL. parvirugata n. sp.L. depressa shows a considerable amount of morphological variation, which is recognised in the two new subspeciesLeptaena depressa visbyensis n. ssp. from the Llandoverian — Wenlockian Visby Formation, andL. depressa lata n. ssp. from the mid-Wenlockian Slite Group. The distribution of the different species is largely substrate-dependent, withLeptaena rhomboidalis andLepidoleptaena poulseni adapted to high-energy environments with firm substrates, whereas the remaining species preferred fine-grained substrates in low-energy environments.   相似文献   

20.
Three species which contain both gyrophoric and lecanoric acids and possess perithecioid ascomata are recognized in the genusDiploschistes. D. badius andD. gyrophoricus are described as new, whileD. subcupreus is reduced to synonymy withD. sticticus. Two species occur in the southern hemisphere, whileD. badius is found in N. America.  相似文献   

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