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1.
Six new species of Lepraria are described from North America: L. barbatica, L. cryophila, L. disjuncta, L. moroziana, L. terricola, and L. xanthonica. Lepraria torii is discussed and its range extended to include boreal eastern North America. Lepraria aurescens is reported as new to North America from Florida. Preliminary keys to the genus in North America are presented.  相似文献   

2.
1. ‘Ecological fitting’ is the process whereby the suites of traits an organism carries from previous evolutionary relationships are used to enable colonisation of novel environments or resources. 2. The concept has much explanatory power in studies of novel host associations, particularly when data suggest a deviation from optimal foraging theory, but is often overlooked in studies of herbivore host selection behaviour in favour of evolutionary hypotheses. 3. In the present study, the concept was used to explain the unusual host selection behaviour of the New Zealand endemic oligophagous butterfly Lycaena salustius Fabricius, the larvae of which feed on endemic Polygonaceae species and the introduced and closely related Fagopyrum esculentum Moench. 4. In field cage oviposition choice assays involving only endemic plants, females preferred to oviposit on the rare Muehlenbeckia astonii Petrie. However, the novel host F. esculentum was overwhelmingly preferred in an additional greenhouse assay. In larval no‐choice performance assays, fitness indicators were variable for the novel host. 5. This imperfect relationship between oviposition preference and larval performance is discussed as a possible example of ecological fitting and highlights the potential use of the concept as an explanatory tool in novel host selection behaviour studies.  相似文献   

3.
Abstract

A reappraisal of the conservation status of the New Zealand frog fauna is presented using the 2008 version of the New Zealand Threat Classification System. Of New Zealand's four extant endemic species, three are judged to be ‘Threatened’ (Leiopelma hamiltoni being ‘Nationally Critical’, and L. pakeka and L. archeyi being ‘Nationally Vulnerable’) and one ‘At Risk’ (L. hochstetteri ‘Declining’). Three Leiopelma species are listed as extinct—they are known from bone deposits in caves throughout the country until some time in the last 1000 years. Three introduced and naturalised Litoria species are abundant in New Zealand although two (L. aurea and L. raniformis) are threatened in their country of origin (Australia). An additional unidentified frog taxon from northern Great Barrier Island is listed as ‘Data Deficient’.  相似文献   

4.
ABSTRACT

Aegilops L. includes wild species from which, over millennia, man has cultivated forms of Triticum L. Ten species of Aegilops occur in Italy. Three species are allochthonous and eight out of ten species are recorded in the Apulia region. Five out of the ten species have been included in Red Lists. Each taxon is presented and discussed, citing old and new sites of occurrence, by examining specimens from many different herbaria, and describing their ecology and habitats, according to the Directive 92/43 EEC. A new taxonomic key, for the identification of all Aegilops species growing in Italy, is provided. The occurrence of Aegilops caudata L., A. peregrina (Hack. in J. Fraser) Maire & Weiller and A. speltoides Tausch in Italy is doubtful.  相似文献   

5.
Five morphologically similar species of Acrapex Hampson (Lepidoptera, Noctuidae, Noctuinae, Apameini), from sub-Saharan Africa are reviewed, including four new species that are described: Acrapex mondogeneta Le Ru n. sp., A. mubale Le Ru n. sp., A. robe Le Ru n. sp. and A. rubona Le Ru n. sp. These five species belong to a species complex that we hereby define as the Acrapex minima group. Host plants of three species are recorded; Acrapex minima is recorded for the first time on a host plant, Digitaria natalensis Stent; A. mondogeneta on Hyparrhenia hirta (L.) Stapf and A. rubona on Imperata cylindrica (L.) P. Beauv. We also conducted molecular phylogenetics (using both Bayesian inference and maximum likelihood) and molecular species delimitation analyses (Poisson tree processes) on a six gene multi-marker dataset (four mitochondrial and two nuclear gene fragments; 4582 nucleotides in length) of 42 specimens and 22 species, including 23 specimens from the Acrapex minima group. The results of the corresponding analyses support the monophyly of the group and the species status of the newly described taxa.  相似文献   

6.
Purpose

The aim of this study was to estimate the level of genomic and phenotypic diversity as well as the genus and species position of bacterial strains isolated from root nodules of Lembotropis nigricans (family Fabaceae).

Methods

The genomic diversity of studied L. nigricans nodule symbionts was examined by using BOX-PCR and AFLP (amplified fragment length polymorphism) fingerprinting techniques. To assign bacteria to the genus, numerical analysis of phenotypic features and comparative analysis of 16S rDNA sequences were performed. The comparative analysis of combined atpD, dnaK, gyrB, and rpoB gene sequences (multilocus sequence analysis, MLSA) was used to determine the most closely related species to the studied bacteria.

Results

Both BOX-PCR and AFLP techniques revealed a high level of genomic heterogeneity of L. nigricans nodulators. Among 33 studied bacteria, 32 genotypes were delineated by the AFLP method and 27 genotypes were identified by the BOX-PCR fingerprinting. The numerical analysis of 86 phenotypic characteristics of L. nigricans nodule isolates and reference rhizobia showed that studied bacteria belong to the genus Bradyrhizobium. Affiliation of L. nigricans nodule isolates to the genus Bradyrhizobium was supported by comparative analysis of 16S rDNA sequences and the concatenation of atpD, dnaK, gyrB, and rpoB gene sequences. MLSA indicated also that L. nigricans microsymbionts are members of Bradyrhizobium japonicum.

Conclusion

L. nigricans root nodule symbionts are members of Bradyrhizobium japonicum and exhibit high phenotypic and genomic diversity important for their survival in soil.

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7.
【目的】将分离自猪肠道粘膜、食糜和粪便的乳酸菌,通过产乳酸能力、生长性能、耐酸和耐胆盐性能及抑菌能力评价,筛选适应养猪生产的潜在益生特性的菌株。【方法】共分离获得155株乳酸菌纯菌株,从中筛选出4株产酸能力较强的乳酸菌,结合生理生化试验及细菌16S rRNA测序鉴定其种属,评价候选乳酸菌的生长情况、耐酸、耐胆盐及抑菌特性。【结果】综合变色时间(8 h)、pH值(3.9)和乳酸含量(100 mmol/L),筛选出4株(L45、L47、L63和L79)候选菌株,经鉴定依次为罗伊氏乳杆菌、植物乳杆菌、约氏乳杆菌和粪肠球菌。该4株乳酸菌均可在体外快速生长;L47和L79能够耐受pH 2.5的酸性环境,L47能够耐受0.5%胆盐环境;各乳酸菌上清液与指示菌共培养,发现对E coli K88和沙门氏菌均产生了抑制作用,其中L47上清液对指示菌的抑制作用较强。【结论】L47具有较好的产酸性能与生长性能、可耐受猪胃酸和肠道胆盐环境,对E.coli K88和沙门氏菌具有较好的抑制作用,说明该乳酸菌具有潜在的益生特性。  相似文献   

8.
Abstract

Limnichthys polyactis n.sp., from the North Island of New Zealand, differs from its nearest relative, the more widespread L. rendahli Parrott, in having a shorter preanal distance (the origin of the anal fin precedes the origin of the dorsal fin, as in the other four species of Limnichthys), fewer cirri along the lower jaw, a shorter snout, and fewer vertebrae. The deepest known occurrence of L. polyactis is 6 m, compared to at least 165 m for L. rendahli. It is suggested that the families Creediidae and Limnichthyidae be combined, the former name having precedence. Notes are given on the taxonomy and distribution of the 13 recognised species, and characters for their separation are keyed.  相似文献   

9.

The flat-headed snake, Tantilla gracilis Baird and Girard is a small reptile belonging to the family Colubridae. Feces from a single T. gracilis from McCurtain County, Oklahoma, USA, was collected and examined for coccidia; it was found to be passing a new species of Caryospora. Oöcysts of Caryospora sargentae n. sp. are spheroidal to typically subspheroidal with a moderately-pitted bi-layered wall, measure (L × W) 20.7 × 19.2 µm, and have a length/width (L/W) ratio of 1.1; a micropyle and oöcyst residuum were absent but one to several small, irregular to spheroidal masses of non-refractile debris within the oocyst was present as well as a polar granule attached to the inner oöcyst wall. Sporocysts are ovoidal and measure 15.0 × 11.0 µm, L/W 1.4; a nipple-like Stieda body is present as well as a distinct rounded sub-Stieda body. The sporocyst residuum is composed of a large, dense, irregular mass of various sized granules located between and often obscuring the sporozoites. This is the third coccidian described from the flat-headed snake. In addition, we include some data on the endogenous development of the coccidian.

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10.
Summary

The first zoeal stages of eleven species of Sesarmidae from the Indo-West Pacific were obtained from ovigerous females. Those of Labuanium scandens, L. rotundatum, L. trapezoideum, L. politum, Metasesarma aubryi, Pseudosesarma crassimanum, Stelgistra stormi, and Sesarmops impressum, are described for the first time, while the first zoeal stages of Clistocoeloma merguiense, Metasesarma obesum and Sesarmops intermedium are re-described. Larval characters of all these species are compared with previously described ones for the family and morphological features are re-evaluated. Minute spines on the telson of the zoeae are described as a new larval character in Sesarmidae and their presence or absence in other grapsoid groups is discussed. The results demonstrate that a recurrent combination of reliable larval characters distinguishes zoeae and megalopae of the examined sesarmids from the rest of the Grapsoidea. This appears to be consistent with recent studies that redefine the Sesarmidae.  相似文献   

11.
S. Mario Sousa 《Brittonia》2010,62(4):321-336
The Lonchocarpus cruentus complex, within sect. Lonchocarpus, is described. This complex is characterized by the presence of a keeled vexillary margin on the pod. Five of the six species described and illustrated are new to science: Lonchocarpus aequatorialis, L. alternifoliolatus, L. guianensis, L. septentrionalis and L. trinitensis. A pronounced flower size difference in the north-south distribution of this complex is shown.  相似文献   

12.
Lixus petiolicola n. sp. is described from Northeastern Turkey. Ecological data and morphological characters are presented in comparison with closely related species Lixus furcatus Olivier from the Palaearctic subgenus Callistolixus Reitter. Host plant of the new species is Prangos sp. (Apiaceae). Female lays eggs in the petiole where immature stages then develop; one generation is produced per year. Lectotypes of Lixus sitta Sahlberg 1823; L. parallelus Boheman 1842; L. eversmanni Hochhuth 1847; L. ferulaginis Apfelbeck 1899, and L. furcatus longicollis Petri 1905 are designated. A new synonymy is established: L. furcatus Olivier 1807 [=L. eversmanni Hochhuth 1847, n. syn.]. The name of L. recurvus Olivier 1807 is resurrected, excluded from synonyms of L. furcatus and attributed to the L. iridis group.  相似文献   

13.
SUMMARY

The occurrence of a ventral sucker-like mouth form in certain populations of Labeo umbratus, which are free from competition by L. aapensis, is reported. It is proposed that this might be an adaptation to feeding off stones which enhances the fish's changes of survival. If this is so, the absense of mouth form variation in Orange River populations illustrates the force of interspecific competition with L. capensis.  相似文献   

14.

A new trace fossil, Lunulichnus tuberosus, is described from fluvial deposits of the Wasatch Formation (early Eocene) at Fossil Butte National Monument, southwestern Wyoming, USA. L. tuberosus are straight, vertical to obliquely oriented, unlined cylindrical burrows with pronounced crescent-shaped wall sculptings. In situ examples of these trace fossils are most commonly preserved as sand-filled casts emanating from the erosional bases of fluvial channel sandstone bodies into underlying floodplain mudstone/siltstone beds. L. tuberosus is interpreted as the dwelling trace of a stream-dwelling decapod crustacean. Excellent preservation of fine detail, particularly their diagnostic crescent-shaped wall sculptings, support the hypothesis that L. tuberosus were excavated in firm substrata subjacent to fluvial erosional surfaces. As such, they are interpreted as constituents of alluvial Glossifungites trace fossil assemblages.  相似文献   

15.
Two new species of Leptolobium from Brazil are described and illustrated. Leptolobium araguaiense, restricted to northern Brazil, is similar to L. panamense, but differs in raceme length, ovary pubescence, flower and bract length, hilum shape, habit, geographical distribution, and preferential habitat. Leptolobium multijugum, from midwestern Brazil, is perhaps most closely related to L. glaziovianum, but it has more numerous leaflets and smaller bracts and bracteoles than any other species in the genus.  相似文献   

16.
Abstract

Heavy metals phytoextraction potential of swollen duckweed (Lemna gibba Linn.) and lesser duckweed (Lemna aequinoctialis Welw.) was determined under greenhouse conditions by exposing to untreated industrial/municipal effluent for a period of 21?days. The nickel (Ni), lead (Pb), and cadmium (Cd) concentrations in water samples were measured weekly and in plant biomass at the termination of experiments. Significant differences (p?<?0.05) between initial and final physicochemical parameters and in heavy metal concentrations of plant and water samples were observed. Periodically measured metal concentrations in mediums revealed that removal percentage was dependent on initial Ni (2.15?mg L?1), Pb (1.51?mg L?1), and Cd (0.74?mg L?1) concentrations. The final metal removal percentages were in the sequence of Ni (97%) > Pb (94%) > Cd (90%) when treated with Lemna gibba L. as compared to control (9–12% reduction). High biomass production of Lemna gibba L. resulted in a large metal reduction in the growth medium and the total plant metal contents were in the sequence of Ni (427?µg) > Pb (293?µg) > Cd (105?µg). The lesser duckweed did not survive under experimental conditions. Based on these results, we concluded that Lemna gibba L. is a good candidate for phytoremediation of wastewater.  相似文献   

17.
18.
ABSTRACT

By employing comparative morphology and anatomy as well as mitochondrial phylogenetics, we have identified three species of Landouria Godwin-Austen, 1918 in Timor-Leste. One of these species is identified as L. cf winteriana (Pfeiffer, 1842), a species originally described from Java, but considered widespread throughout the Indonesian archipelago. The two other species are newly described as L. timorensis n. sp. and L. montana n. sp., respectively. Landouria timorensis n. sp. is similar to L. winteriana, but differs by a smaller shell and details of its penial morphology. Landouria montana n. sp. is only found at higher altitudes and is readily distinguishable by its distinctive shell. A mitochondrial phylogeny reveals L. omphalostoma from Yunnan as the sister lineage of all Sunda Islands species. Based on this observation, we maintain the systematic placement of the Sunda Islands species in Landouria despite some minor differences in their genital anatomy. Furthermore, our phylogeny demonstrates that the East Asian genus Aegista Albers, 1850 is the probable sister taxon of Landouria. However, we reject the proposal by Hirano et al. ([2014] Substantial incongruence among the morphology, taxonomy, and molecular phylogeny of the land snails Aegista, Landouria, Trishoplita, and Pseudobuliminus (Pulmonata: Bradybaenidae) occurring in East Asia. Molecular Phylogenetics and Evolution 70, 171–181) to synonymise both genera based on their markedly distinct reproductive anatomy.  相似文献   

19.
《Journal of bryology》2013,35(4):270-274
Abstract

A new species of Lepidopilidium (Pilotrichaceae, Hookeriales), L. crispifolium, sp. nov. from St Helena, South Atlantic Ocean is described and illustrated.  相似文献   

20.
Purpose

The present study was undertaken to evaluate in vitro prerequisite probiotic and technological characteristics of ten Lactococcus strains isolated from traditional goat skin bags of Tulum cheeses from the Central Taurus mountain range in Turkey.

Methods

All isolates were identified based on the nucleotide sequences of the 16S rRNA gene. Eight isolates belonged to Lactococcus lactis and two belonged to Lactococcus garvieae. Probiotic potential was determined from resistance to acid and bile salt, resistance to gastric and pancreatic juices, resistance to antibiotic, auto-aggregation, co-aggregation, diacetyl, hydrogen peroxide and exopolysaccharide productions. Technological properties were verified by alcohol, NaCl and hydrogen peroxide resistance and temperature tests.

Results

L. lactis NTH7 displayed high growth at all alcohol concentrations while L. lactis NTH4 grew very well even at NaCl concentrations of 10%. All strains showed to some extent resistance to acid and bile. Five strains exhibited desirable survival in gastric juice (pH 2.0), while three strains survived in pancreatic juice (pH 8.0). All Lactococcus isolates were sensitive to ampicillin, chloramphenicol, erythromycin, vancomycin, kanamycin, gentamycin and tetracycline. Also, only L. lactis NTH7 from among the isolates showed resistance against penicillin. L. lactis NTH10 and L. lactis NTH7 had higher auto-aggregation values in comparison with all other strains. All the strains demonstrated a co-aggregation ability against model food pathogens, particularly, L. lactis NTH10 which showed a superior ability with L. monocytogenes. All the ten strains produced H2O2 and exopolysaccharide (EPS); however, diacetyl production was detected for only four strains including L. lactis NTH10.

Conclusion

These results demonstrate that the L. lactis NTH10 isolate could be regarded as a favorable probiotic candidate for future in vivo studies.

  相似文献   

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