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1.
A new euglenoid genus and species, Tetreutreptia pomquetensis, is described from winter waters of Maritime Canada. This phototrophic species is characterized by four emergent heterodynamic flagella, two about the length of the cell and two less than one-half this length. Tetreutreptia pomquetensis has features in common with species of Eutreptiella while it differs in several respects from any of the described species of that genus. It could be assigned to the order Eutreptiales or Euglenamorphales sensu Leedale or the order Euglenales sensu Farmer. This new alga has a narrow range of temperature tolerance; it grows best from 0° to 7° C and dies at temperatures above 10° C. The optimum salinity for growth was near full-strength seawater. Growth conditions for the alga define the conditions whence this species was isolated.  相似文献   

2.
Species ofAnthostomella reported from Brunei have been re-examined and the data is summarized in this paper. Five species are accepted, four are synonyms of previously described species and one is a new species. The new speciesAnthostomella oblongata is described and illustrated and a list ofAnthostomella species known from Brunei and a key to these species are provided.  相似文献   

3.
Summary Diel activity patterns of carabids species caught in pitfall traps in a subalpine birch forest north of the Arctic Circle are described. Patrobus assimilis Chaud. and Notiophilus aquaticus L. were the most common species and were active at all times of the day with peak activity at noon. Seven less common species and the larvae of Notiophilus aquaticus L. showed similar activity patterns. There was a positive correlation between the mean diel variation in temperature and the activity of the different species. Although day to day variations in temperature influenced the level of activity, it had little effect on the daily activity patterns. The adaptive significance of the diurnal activity patterns of carabid beetles in northern areas is discussed in relation to low night temperatures and high predation pressure from birds.  相似文献   

4.
The second part of the publication is devoted to the Melamphaes species (family Melamphaidae), which are characterized by 20 and more rakers on the first gill arch, by seven soft rays in the ventral fin, by absence of a temporal spine, by 14–15 rays in the pectoral fin, and by 11 abdominal vertebrae. M. polylepis is characterized by circumtropical range (Atlantic Ocean, Indian Ocean, western and central Pacific Ocean). Newly described species M. falsidicus is described from the northern Atlantic Ocean, where it was sampled between 34°N and 58°N. Before, this species was defined as M. microps. Another newly described species, M. pachystomus, is described along the Peruvian Coast. M. macrocephalus is redescribed. This species inhabits the eastern tropical Pacific Ocean (approximately between 30°N and 23°S). One of the studied specimens of M. macrocephalus was characterized by larger body size (SL = 128 mm) than was described before for this species. M. leprus is known currently by single findings from the eastern tropical Atlantic Ocean (between 11°N and 4°S). This species was also found in the samples obtain in the Gulf of Guinea.  相似文献   

5.
Nakagiri  Akira  Newell  Steven Y.  Ito  Tadayoshi 《Mycoscience》1994,35(3):223-232
Two new pythiaceous fungi were obtained from decaying leaves submerged in saltmarsh environments of the east coast of the U.S.A., or fringing mangroves in the Bahama Islands, and are described here asHalophytophthora tartarea andH. masteri. The two species have superficially similar zoosporangia whose dehiscence tubes have ragged-looking apices. However, differences in fine structures and development of the dehiscence tube and plug, characteristics of the dehiscence plugs, and presence or absence of vesicles clearly distinguish the two species.Halophytophthora masteri is the only species ofHalophytophthora that has a zoospore release mechanism involving both an extruded plug and a vesicle. Cultural properties concerning growth and asexual reproduction at various salinities and temperatures are also different between the two, probably reflecting adaptation to their respective habitats. Though zoospore release inH. masteri occurs spontaneously from mature zoosporangia, it is remarkably enhanced inH. tartarea and alsoH. masteri by mildly dehydrating mature zoosporangia followed by rewetting with seawater, which suggests a possible relation between the asexual reproduction of these oomycetes and the tidal rhythm in their natural habitats.  相似文献   

6.
A new species of Campylocentrum from the Colombian Andes, C. guarinae, is described, illustrated and placed within a key to Colombian species of the genus. The new species resembles C. lansbergii from which it differs in vegetative and floral characters. The main differences between these species are described and illustrated.  相似文献   

7.
Bathylaimus anatolii sp. n. is described and illustrated. The new species resembles B. capacosus Hopper, 1962 but differs from the latter by shorter setae, body and by the c-index and has three onchs in the buccal cavity. The seasonal dynamics of abundance, proportion of adults and larvae, as well as the gravid and nongravid females and males were studied. An elongated breeding season from April to November and a long spring-summer peak of population density with a winter minimum at low temperatures for B. anatolii are characteristic in Peter the Great Bay.  相似文献   

8.
9.
Platoma abbottiana (Gymnophlaeaceae; Gigartinales), a new species of benthic red algae, is described from Isla Mejía and is the second member of this genus reported from the Gulf of California, Mexico. Vegetative anatomy and reproductive details of the carpogonial and auxiliary cell branches of the new species are described and illustrated. Geographical distributions of the seven previously described Platoma species are given. Their distinguishing morphological characteristics are compared to those of the new species. The correct time and place of valid publication of the generic name, Platoma, and some of its binomials are discussed.  相似文献   

10.
《Journal of bryology》2013,35(3):161-164
Abstract

The genus Lobatiriccardia Furuki is reported as new to China, from the Dulong River valley, Gaoligong Shan range, Yunnan Province and this material is described as a new species endemic to China, Lobatiriccardia yunnanensis Furuki & D.G. Long, the fifth known species in the genus. The differences between the new species and the other members of the genus are enumerated, along with a key to all known species of Lobatiriccardia.  相似文献   

11.
The discovery that cryptic species are more abundant than previously thought has implications for weed biological control, as there is a risk that cryptic species may be inadvertently released with consequences for the safety of the practice. A cryptic species of a biological control agent released for the control of the invasive alien macrophyte, water hyacinth, Eichhornia crassipes (C. Mart.) Solms. (Pontederiaceae), was recently discovered in South Africa. The two species were considered a single species prior to genetic analysis and interbreeding experiments. The original biological control agent retains the name Eccritotarsus catarinensis (Carvalho) (Heteroptera: Miridae) whereas the new species has been described as Eccritotarsus eichhorniae Henry. In this study, we compared the host specificity, efficacy, and thermal physiologies of the two species. The host specificity of the two species within the Pontederiaceae was very similar and both are safe for release in South Africa. Comparison of the per capita impact of the two species indicated that E. eichhorniae was the more damaging species but this is likely to be influenced by temperature, with E. catarinensis being more effective under lower temperatures and E. eichhorniae being more effective under higher temperatures. Releasing the correct species for the thermal environment of each release site will improve the level of control of water hyacinth in South Africa. This example highlights the need to keep populations of biological control agents from different native range collection localities separate, and to screen for host specificity and efficacy.  相似文献   

12.
13.
Lagerstroemia menglaensis C. H. Gu, M. C. Ji & D. D. Ma, a new species of Lythraceae from Xishuangbanna, Yunnan, China is described and illustrated. The morphological characteristics of the new species and two morphologically similar species (L. guilinensis and L. venusta) are compared, and a key to distinguish between them is provided.  相似文献   

14.
Chad Walter  T. 《Hydrobiologia》1994,(1):123-130
Two closely related and often confused species of Pseudodiaptomus from the Lobus-species group, P. lobipes and P. binghami are redescribed from various locations along the east coast of India. These species predominately occur in freshwater though they can survive temporary periods of increased salinity. The distinctive features of the species are found on: female caudal ramal setae, female and male urosome 1–2 spinulation patterns, and fifth legs. A new species P. mixtus from Bangladesh is described.  相似文献   

15.
《Journal of bryology》2013,35(2):251-262
Abstract

Thamnobryum cataractarum sp. nov. is described from Yorkshire, England. It is most closely related to T. fernandesii from Madeira and is also similar to T. angustifolium from Derbyshire, England. The three species are compared, and the habitat of the new species is described. T. fernandesii and T. cataractarum are retained in Thamnobryum rather than in Crassiphyllum Ochyra.  相似文献   

16.
Potentilla jiaozishanensis, a distinct new species of Rosaceae from Yunnan, China, is described and illustrated. Morphologically, it is closely related to P. stenophylla var. stenophylla but clearly differs from the latter by its bidentate leaflets, lanceolate epicalyx‐segments that are longer than the sepals, villose ovaries and achenes. Moreover, the pollen grains of P. jiaozishanensis are markedly different from those of P. stenophylla var. stenophylla in size and shape. The newly described species is endemic to the Jiaozishan Mountains, southwest China.  相似文献   

17.
Impatiens shimianensis Q. Luo (Balsaminaceae), a new species from Shimian county in southwestern Sichuan province, China, is reported and its morphological characteristics are described and illustrated. Pollen grain morphology and seeds under SEM are also described. The new species is somewhat similar to I. bahanensis, I. brachycentra, I. laxiflora, I. parviflora and I. racemosa, but differs mainly by having leaf blades with white short stiff adpressed hairs; basal lobes of lateral united petals triangular, distal lobes lanceolate; and lower sepal salver‐shaped. The distinguishing characters for these six Impatiens species are given in a table.  相似文献   

18.
Frisch  Dagmar 《Hydrobiologia》2001,(1):285-293
Life cycles of the freshwater cyclopoids Cyclops strenuus Fischer and Cyclops insignis Claus are described from populations of one permanent and two temporary waters in a floodplain area. The abundance of these two species was studied in detail, with special regard to instars surviving summer drought. Both species coexist in two locations during the flood period in the cold season. Cyclops insignis is strictly univoltine, whereas Cyclops strenuus may produce two generations. Differences in timing of egg production, mortality of juvenile instars at four different temperatures, and survival of resting stages in terrestrial conditions are discussed as possible characteristics facilitating the coexistence of the two species.  相似文献   

19.
20.
Type examination ofTrametes gilvoides revealed that it is distinct from the fungus hitherto known asPhellinus gilvoides in Japan.Phellinus setifer sp. nov. is described for the Japanese materials. This species is characterized by effusedreflexed basidiocarps with strigose pileus surface, often dentate dissepiments, subulate setae, and cylindrical basidiospores.Phellinus acontextus, known only from the type material collected in Nepal, is newly reported from Japan. This species is characterized by sessile and often pendent basidiocarps with multisulcate pileus surface, very thin context, lack of setae, and dark-colored basidiospores. Cultural characters of the two species are also described.Phellinus acifer comb. nov. is proposed.Phellinus contiguus andP. ferreus are newly reported from Japan.  相似文献   

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