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961.
《Journal of Natural History》2012,46(41-42):2577-2604
The influence of temporal variation in the host specificity of invertebrates to estimates of biodiversity is rarely considered. While patterns at large spatial scales have stimulated much attention, such comparisons are constrained for southern-hemisphere biomes because the patterning of invertebrates on plants is largely unknown. Here, we analyse variation of plant-dwelling Hemiptera from 15 understorey plant species over 18 months in the south-west Australian biodiversity hotspot. Analyses showed significant interactions in species composition between sampling period and plant species. Fauna that were “effectively specialized” (host-specificity index) to plants changed with season, although this was also related to the number of singletons and overall species richness. Sampling from a single season also overestimated the degree of host specificity by 52% and underestimated the perception of species richness when an outbreak of a particular herbivore occurred. High host-specificity values (12.7 hemipteran species per plant) support the case for high estimates of global arthropod richness. 相似文献
962.
963.
《Journal of Natural History》2012,46(3):489-506
Four new species within the crangonyctoid amphipod genus Paramelita are described from material collected from small streams in the southwestern Cape, South Africa. Two of the species are large, with robust second antennae which exceed the first in length, especially in adult males. The third species is recognized by its slender pereopods and its densely setose second antennae, and the fourth by its small size and relatively short, slender, unmodified second antennae. All of these species have an unmodified pereopod 3, and lack teeth, spines, ridges or lobes on antenna 2, features common to many of the known Paramelita species. Morphological similarities between the four new species and 19 previously known species of Paramelita are discussed. 相似文献
964.
《Journal of Natural History》2012,46(17-18):1113-1129
Eupelmus vesicularis (Retzius) is considered to be a widespread and polyphagous parasitoid recorded from more than 200 hosts. The aim of this study was to determine whether two colour forms of the putative species represent two different morphs of a single species or a pair of cryptic species. Three different methods – morphometric analysis, allozyme electrophoresis and evaluation of host preferences – were used to investigate the existence of two cryptic species. Bivariate and multivariate analyses clearly indicate two species that are also distinguishable electrophoretically at the Idh-2, G6pdh, Me, Pgm and Xdh loci. The evaluation of host preferences indicates some overlap in host range between the two species. 相似文献
965.
Habitat characterization and potential distribution of Tylototriton vietnamensis in northern Vietnam
《Journal of Natural History》2012,46(17-18):1161-1175
The habitat preferences of the endemic Vietnam Crocodile Newt, Tylototriton vietnamensis were investigated on two scales: (1) at Yen Tu Nature Reserve, Bac Giang Province, Vietnam, while compiling information about pond occupancy and developing a qualitative comparison among breeding sites and (2) by developing a Species Distribution Model based on climate and land cover data identifying further suitable habitats in northern Vietnam. A factor analysis followed by a multiple linear regression showed 94% support for our occupancy ranking model. Our results suggest that T. vietnamensis preferentially inhabits small pools with long hydroperiod and pH above 4.3. Suitable areas for the species have higher incidence in northern regions, where undisturbed vegetation and temperature-related variables seem to make greater contributions. Additionally, these potentially suitable areas are strongly fragmented and only a few are under IUCN protection, increasing their vulnerability towards further degradation. 相似文献
966.
通过监测紫金山南、北坡海拔约300m处的气温和湿度,发现紫金山南、北坡小气候存在差异,呈现南坡温暖干燥,北坡阴冷潮湿的特征,其中夏季南北坡温差可达2.6℃,相对湿度约相差6%.紫金山南、北坡海拔约300m地带主要植物群落的组成结构表明:南、北坡植物群落中有很多相同的优势种和伴生种,其中苦槠(Castanopsis sclerophylla)、女贞(Ligustrum lucidum)是最重要的常绿成分;落叶成分中,栎属(Quercus)树种和枫香(Liquidamba formosana)占重要地位.但在南坡与北坡观察到的偶见种却有明显不同.综合分析小气候与植物群落物种组成的关系表明:小气候的微弱差异虽然不影响紫金山南、北坡植物群落中的优势成分和伴生成分,但对群落中的偶见种成分却有明显影响,紫金山南坡植物群落中多生长喜暖、耐干燥的偶见种,而北坡的偶见种大多是耐寒、喜湿物种. 相似文献
967.
ABSTRACT The formation of scientific names for species may be challenging for modern systematists without a background in Latin or familiarity with the International Code of Zoological Nomenclature. Therefore, presented here are 10 pragmatic and simplified strategies for creating zoological species names. They are intended to demystify the derivation and construction of species names and facilitate the process of naming species for a broad audience of zoologists working in systematics. 相似文献
968.
Tomás M. Rodríguez-Cabrera L. Yusnaviel García-Padrón Andrés R. Acosta Galvis Rafael O. de Sá 《Journal of Natural History》2018,52(29-30):1883-1892
The Neotropical genus Leptodactylus is currently represented by three species in the West Indies (Leptodactylus albilabris, Leptodactylus fallax and Leptodactylus validus). Based on morphological, acoustic and molecular evidence, we document the presence of a fourth species in the Caribbean region, Leptodactylus fragilis (Brocchi, 1877). The species was found at two localities in western Cuba, and molecular data suggest a northern South American origin, possibly Venezuela, for these populations. We discuss the potential invasive status of L. fragilis, based on its known distribution, relative abundance, behaviour and possible impacts on native species of Cuban amphibians. 相似文献
969.
为了解贵州宽阔水国家级自然保护区白辛树(Pterostyrax psilophywus)群落物种组成及种群结构特征,选取保护区内白辛树群落主要分布范围进行调查分析.结果表明:调查群落样地内共有维管植物42科, 71属, 84种,其中蕨类植物1科, 1属, 1种;种子植物41科, 70属, 83种;无裸子植物,被子植物41科, 70属, 83种;单子叶植物4科, 5属, 7种;双子叶植物37科, 65属, 76种.物种组成较为单一.白辛树虽占据优势,但龄级结构不正常,呈"两头多,中间少".群落物种多样性指数及均匀度指数不高.白辛树幼苗和幼树极少,更新困难,且受林下金佛山方竹(Chimonobambusa quadrangularis)干扰较强,大径阶植株比重大,年龄结构总体呈衰退型.种群在该区处于濒危状态,亟待保护. 相似文献
970.
《Journal of Natural History》2012,46(6):1397-1441
The state of knowledge of Australian fish parasitic ascardioids is briefly reviewed. The following species are described in full: Hysterothylacium cornutum, H. pelagicum, H. scomberoidei n. sp. Additional data are provided for Iheringascaris inquies. Maricostula n. gen. is established for those species that have lips with lateral flanges, deep postlabial grooves, interlabia, and elongate intestinal caecum, pyriform ventriculus, long sac-like ventricular appendix, an expanded filamentar excretory system and excretory pore near the nerve ring. The males of all the species have precloacal crests. Species included are: M. caballeroi (Deloya), M. cenatica n. sp., M. histiophori (Yamaguti), M. incurva (Rudolphi), M. makairi n. sp. and M. tetrapteri n. sp. All are recorded from billfishes, and all but M. caballeroi are recorded from Australian waters. The systematic position of the genus is discussed. New characters of taxonomic utility used in the discrimination of fish parasitic ascaridoids are discussed. These include fine details of alae, male caudal crests and papillae. We demonstrate that these characters can be used to separate species of Maricostula. Remarks are also given on nomenclatural problems within the Indo-Pacific fish parasitic Ascardioidea. 相似文献