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981.
Herbertia crosae (Iridaceae) is described from the stony grasslands of northwestern Uruguay. The new species resemblesHerbertia lahue but can be easily distinguished by the narrower leaves, slender habit, the smaller pale lilac flowers, the presence of yellow
spots at the base of the tepals, the red, adpressed hairs along the filament column, the presence of filaments free at the
apex, the channeled style arm, the recurved secondary divisions of the style arm, and the smaller fruits. A key to the species
of the genus is provided in which five species are now recognized. 相似文献
982.
Age and growth of ocellated icefish, Chionodraco rastrospinosus DeWitt and Hureau, 1979, from the South Shetland Islands 总被引:1,自引:0,他引:1
Age and growth of ocellated icefish, Chionodraco rastrospinosus, were investigated using counts of annual growth increments from sagittal otoliths. Samples were collected during research
surveys by benthic trawl carried out around Elephant and South Shetland Islands in January–February 2002 and December 2006–January
2007. A total of 290 specimens were selected for the study, consisting of 120 females and 170 males. The age of fish was estimated
by counting annuli on transverse sections obtained by grinding and polishing whole otoliths embedded in epoxy resin. The precision-of-age
estimates within and between readers were tested applying both the average percent error (APE) and the coefficient of variation
(CV). The estimated age-range was 1–12 for both sexes of C. rastrospinosus. Applying the von Bertalanffy growth function to the age–length data, a growth curve was obtained for each sex. The estimated
values of VB growth parameters L
∞
and k were, respectively, 47.9 cm and 0.28 for females and 42.9 cm and 0.36 for males. Compared to other congeneric species, the
growth performance of C. rastrospinosus was relatively high, being 2.82 and 2.81 in males and females, respectively. Age at sexual maturity was estimated to be about
4 years in both sexes. C. rastrospinosus captured in the studied area consisted mainly of adult specimens between 3 and 8 years, with few older fish. 相似文献
983.
South polar skuas, SPS, (Catharacta maccormicki) and brown skuas, BS, (C. antarctica lonnbergi) are regarded as opportunistic predators. When breeding in sympatry, BS feed mainly on penguin eggs and chicks, while SPS
forage almost exclusively at sea. The objective of this study was to determine the diet composition of adult SPS and BS breeding
in sympatry, in order to assess food resource partitioning between these species. The total number of food items consumed
was 375 for BS and 682 for SPS in 1992–93, and 427 for BS and 579 for SPS in 1995–96. The pellets composition was significantly
correlated between skua species for the same breeding season (r
s = 0.67, p = 0.0062 and r
s = 0.81, p < 0.001, for 1992–93 and 1995–96, respectively), and between breeding seasons for the same skua species (r
s = 0.71, p = 0.001 and r
s = 0.81, p < 0.001, for SPS and BS, respectively). Trophic niche breadth of BS was wider than that of SPS (B
A(BS) = 0.28 and B
A(SPS) = 0.24; Z = 7.67; p < 0.001). The trophic niche overlap between BS and SPS was over 65% in both breeding seasons. In agreement with other studies
on the diet of these skua species in situations of sympatry, SPS consumed more fish and BS consumed more birds. 相似文献
984.
Predicting species distributions across the Amazonian and Andean regions using remote sensing data 总被引:3,自引:1,他引:2
Wolfgang Buermann Sassan Saatchi Thomas B. Smith Brian R. Zutta Jaime A. Chaves Borja Milá Catherine H. Graham 《Journal of Biogeography》2008,35(7):1160-1176
Aim We explore the utility of newly available optical and microwave remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and QuikSCAT (QSCAT) instruments for species distribution modelling at regional to continental scales. Using eight Neotropical species from three taxonomic groups, we assess the extent to which remote sensing data can improve predictions of their geographic distributions. For two bird species, we investigate the specific contributions of different types of remote sensing variables to the predictions and model accuracy at the regional scale, where the benefits of the MODIS and QSCAT satellite data are expected to be most significant. Location South America, with a focus on the tropical and subtropical Andes and the Amazon Basin. Methods Potential geographic distributions of eight species, namely two birds, two mammals and four trees, were modelled with the maxent algorithm at 1‐km resolution over the South American continent using climatic and remote sensing data separately and combined. For each species and model scenario, we assess model performance by testing the agreement between observed and simulated distributions across all thresholds and, in the case of the two focal bird species, at selected thresholds. Results Quantitative performance tests showed that models built with remote sensing and climatic layers in isolation performed well in predicting species distributions, suggesting that each of these data sets contains useful information. However, predictions created with a combination of remote sensing and climatic layers generally resulted in the best model performance across the three taxonomic groups. In Ecuador, the inclusion of remote sensing data was critical in resolving the known geographically isolated populations of the two focal bird species along the steep Amazonian–Andean elevational gradients. Within remote sensing subsets, microwave‐based data were more important than optical data in the predictions of the two bird species. Main conclusions Our results suggest that the newly available remote sensing data (MODIS and QSCAT) have considerable utility in modelling the contemporary geographical distributions of species at both regional and continental scales and in predicting range shifts as a result of large‐scale land‐use change. 相似文献
985.
Pseudobagrus brachyrhabdion sp. nov., from the Yuan Jiang and Xiang Jiang of the middle Yangtze River drainage in Hunan and Guizhou Provinces, South
China, is described herein. It is distinguished from all other Pseudobagrus species with a truncate or slightly emarginated caudal fin by an unique combination of the following characters: supraoccipital
plate and nuchal plate broadly interspaced and covered with skin; nasal barbels only at most reaching anterior margin of eye;
maxillary barbels reaching slightly beyond posterior margin of eye; outer mandibular barbels extending to posterior margin
of eye; dorsal fin with a somewhat convex distal margin, origin nearer to pectoral-fin insertion than to pelvic-fin insertion;
dorsal-fin spine shorter than pectoral spine, with a somewhat serrated posterior margin; pectoral-fin spine with a smooth
anterior margin; anal fin with 20–23 rays, base length 23.8–32.0% of standard length, posterior end of anal-fin base anterior
to posterior end of adipose fin base; no longitudinal black band extending along flank; eyes large, diameter 16.3–23.7% of
head length; and number of vertebrae 5 + 43–46. 相似文献
986.
D. J. Nicholas Hind 《Kew Bulletin》2008,63(3):515-516
Summary New combinations are provided for nine taxa in the Bolivian Compositae — four in Dendrophorbium (Senecioneae), four in Vernonia (Vernonieae) and one in Viguiera (Heliantheae) — in advance of an on-line publication of a ‘Preliminary checklist of the Compositae of Bolivia’. 相似文献
987.
988.
SYSTEMATIC DESCRIPTION AND PHYLOGENETIC AFFINITY OF TUBULAR MICROFOSSILS FROM THE EDIACARAN DOUSHANTUO FORMATION AT WENG'AN, SOUTH CHINA 总被引:1,自引:0,他引:1
PENGJU LIU SHUHAI XIAO† CHONGYU YIN CHUANMING ZHOU‡ LINZHI GAO FENG TANG 《Palaeontology》2008,51(2):339-366
Abstract: This paper provides a systematic treatment of tubular microfossils collected from dolomitic phosphorites of the Ediacaran Doushantuo Formation at Weng'an, South China. These microfossils were investigated using petrographic, acid extraction and re-embedding techniques. Four morphological genera and five morphospecies are described: Ramitubus increscens gen. et sp. nov., Ramitubus decrescens gen. et sp. nov., Sinocyclocyclicus guizhouensis , Quadratitubus orbigoniatus , and Crassitubus costatus gen. et sp. nov. They are characterized by cylindrical ( R. increscens , R. decrescens , S. guizhouensis and C. costatus ) or tetragonal ( Q. orbigoniatus ) tubes with closely spaced cross-walls. Ramitubus has mostly complete cross-walls, whereas all other taxa have regularly intercalated complete and incomplete cross-walls. Some of them branch dichotomously ( R. increscens and R. decrescens ), others have a longitudinal ridge running along a curved tube ( C. costatus ).
The palaeoecology, ontogeny, and phylogenetic affinity of these microfossils are still uncertain. They probably represent non-biomineralizing organisms in the Ediacaran ocean. Ramitubus (and possibly all other morphotaxa described in this paper) was probably benthic and grew unidirectionally and episodically. The incomplete cross-walls could have been formed through terminal addition or, alternatively, through intercalary insertion. It is possible that some or all morphotaxa described may represent ontogenetic or ecophenotypic variations of one or a few closely related biological species. If so, then the combination of morphological features (complete and incomplete cross-walls, tetraradial symmetry, and longitudinal ridge) can negate a cyanobacterial or algal interpretation, and point to a tentative cnidarian affinity. 相似文献
The palaeoecology, ontogeny, and phylogenetic affinity of these microfossils are still uncertain. They probably represent non-biomineralizing organisms in the Ediacaran ocean. Ramitubus (and possibly all other morphotaxa described in this paper) was probably benthic and grew unidirectionally and episodically. The incomplete cross-walls could have been formed through terminal addition or, alternatively, through intercalary insertion. It is possible that some or all morphotaxa described may represent ontogenetic or ecophenotypic variations of one or a few closely related biological species. If so, then the combination of morphological features (complete and incomplete cross-walls, tetraradial symmetry, and longitudinal ridge) can negate a cyanobacterial or algal interpretation, and point to a tentative cnidarian affinity. 相似文献
989.
This study describes the spawning of the fatheads Psychrolutes marmoratus and Cottunculus granulosus, two psychrolutid species that inhabit the shelf edge and continental slope of the south‐west Atlantic. Females lay large eggs of c. 2·5 mm (P. marmoratus) and 4·5–5·0 mm (C. granulosus); fecundity is from the hundreds (C. granulosus) to a few thousand eggs (P. marmoratus). Egg maturation is synchronous in P. marmoratus with an autumn–winter peak of spawning and group‐synchronous in C. granulosus, which reproduces all year round. In the fishery, females predominate among adult fish in both species, possibly indicating male nest guarding on hard grounds inaccessible to fishing vessels. The reproductive strategy of representatives of the Psychrolutidae is similar to that of other sculpins of the superfamily Cottoidea. 相似文献
990.
When Good Lawyers Write Bad History: Unreliable Evidence and the South China Sea Territorial Dispute
Bill Hayton 《Ocean Development & International Law》2017,48(1):17-34
The recent award by an arbitral tribunal in a case brought by the Philippines against China gives lawyers reason to reexamine the historical evidence put forward by claimants in the South China Sea disputes. While the Tribunal was barred from considering territorial or boundary questions, it did cast doubt on the historical narrative rule that China has asserted in support of its claims. Fresh evidence from other sources also suggests that discussions of these matters need to move beyond arguments put forward in a small number of papers published more than thirty years ago. A close examination of the references used in those papers shows that they relied upon highly partisan Chinese sources. Recent historical research has produced new facts about the development of the competing territorial claims in the South China Sea, but international legal discourse has yet to take these findings into account. This article examines some of the key works in the field and calls for them to be reassessed and for future discussion of the disputes to be based upon verifiable and contextualized evidence rather than on nationalist assertions. 相似文献