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排序方式: 共有321条查询结果,搜索用时 15 毫秒
1.
A new barbine cyprinid fish, Acrossocheilus multistriatus sp. nov., is described from the Zhujiang River(Pearl River) basin in South China. It is separated from all other barred congeners except A. monticola by its unique coloration pattern of 8–12 vs. 5–7 vertical dark bars on the dorsum and flank. Although 8 vertical black bars are also present in specimens of A. monticola, the new species is distinct from it by having a well-developed(vs. poor-developed) lower lip, with or without a median interruption(vs. with a median interruption which wider than 1/2 mouth width) on lower jaw, the lower jaw entirely covered(vs. uncoverd) by the lower lip, body depth 22.57%–25.22% SL(vs. 25.64%–32.26% SL). Additional characteristices as follows: last simple dorsal-fin ray soft without serration; dark stripes on membranes between dorsal-fin rays; dark stripes absent on membranes between anal fin rays; maxillary barbels longer than eye diameter, extending to posterior edge of eyes. 相似文献
2.
《Current biology : CB》2020,30(12):2260-2274.e6
3.
E. Mark Williams Mogens L. Glass Norbert Heisler 《Environmental Biology of Fishes》1993,37(4):407-413
Synopsis The oxygen transport characteristics and the acid-base status of carp blood was studied in vitro by equilibration of blood samples with and without addition of 5mmol l–1 of nitrite for 30 min at various Po2 values in combination with Pco2 of 1.5 and 5.7mmHg (0.2 and 0.76kPa). After equilibration pH, Po2, Pco2, and Co2 as well as methaemoglobin and HCO3
– concentration were determined and oxygen dissociation curves established. At Pco2 of 1.5mmHg (0.2kPa) oxygen affinity, expressed by a normal P50 of 3.3mmHg (0.44kPa) was unaffected by nitrite exposure, whereas at Pco2 5.7 (0.76kPa), nitrite exposure shifted P50 from 7.59mmHg (1.01kPa) to 21.9mmHg (2.92kPa). Methaemoglobin formation was greater at the higher Pco2 and increased with falling Po2. Erythrocyte shrinkage and rising plasma [HC03
–] during nitrite exposure indicated that the erythrocyte osmoregulation was significantly affected. The present results indicate significantly reduced oxygen affinity upon exposure of carp blood to nitrite. This result contrasts with findings in mammalian blood, where oxygen affinity is greatly enhanced. 相似文献
4.
5.
中国鲴亚科鱼类同工酶和骨骼特征及系统演化的探讨:鲤形目:鲤科 总被引:3,自引:1,他引:2
本文对鲴亚科Xenocyprinae共4属6种鱼和鲢亚科Hypophthal michthyinae的鲢、鳙Aristichihys nobilis进行了骨骼系统的研究,并对鲴亚科的6种鱼同工酶谱型,进行了分析比较。鲢亚科虽然具有鲴亚科的共同祖征和全部离征,但因其有较多的特化性状,仍将其列为和鲴亚科并列的一个亚科。应用分支系统学原理推导出鲴亚科的系统发育图。鲴亚科6种鱼的肝、肾、心、眼的晶状体、鳍、脑,肌肉等7种组织5种同工酶(LDH,MDH,ES,ADH,G6PDH)的电泳分析表明,生化分类和经典分类结果完全一致。 相似文献
6.
Cynthia A. Paszkowski 《Environmental Biology of Fishes》1986,17(3):227-233
Synopsis Laboratory experiments examined the foraging performances of a dietary generalist, bluegill,Lepomis macrochirus, and a dietary specialist, golden shiner,Notemigonus crysoleucas, as they fed from devices simulating four foraging sites (bottom substrate, water column, submerged macrophytes, and water surface). Fishes foraged in monospecific and mixed-species groups of two and four individuals. For monospecific groups, foraging rates of bluegills did not differ among the four sites, but golden shiners had significantly higher rates on bottom and midwater sites than on plant and surface sites. The size of monospecific groups did not affect foraging rates of either species. In mixed-species trials, bluegills removed more food items than golden shiners from plant and surface sites in two- and four-fish groups and from bottom sites in two-fish groups. Bluegills' foraging performances improved with experience, golden shiners' performances did not. Experimental results are discussed with respect to interactions between bluegills and golden shiners in natural assemblages. 相似文献
7.
Many recent studies have employed molecular markers to uncover important aspects of mating systems in teleost fishes. The fathead minnow (Pimephales promelas) is a nest‐building North American cyprinid that spawns multiply and exhibits exclusive male parental care. A battery of microsatellite markers was developed to analyse paternity in this species. The seven characterized loci possess four to 31 alleles and expected heterozygosities of 0.455–0.974. In combination, they elicit an exclusion probability of 0.999, a desirable level for paternity analysis. In addition, cross‐amplifications were conducted to test primer efficacy in 13 other taxa, including two congeners. 相似文献
8.
Most adult Barbus haasi , at a 1950 m-long site in Vallvidrera creek, were highly sedentary and resided within a home range <20 m (32 m2 ), while a small group were more mobile. On successive sampling occasions, between 52·3 and 64·9% of fish were recaptured in the same 10-m-long section in which they had previously been captured. Movements over long distances were infrequent, and only 5·6% of the fish moved >100 m. The movement pattern of the population was seasonally stable, although the mean distances were slightly greater in summer because of the medium-range movements of a few individuals. Overall, upstream and downstream movements were equally common but a significant downstream movement occurred in spring. The size of the fish did not influence the movement rate. Fish inhabiting those sections of the stream with greater depth, slower current and more cover had a lower movement rate than fish occupying shallower, exposed sections. The restricted movement of B. haasi could increase the survival of fish by increasing the probability of staying in the remaining pools during summer dry-out, and may therefore be of adaptive significance. 相似文献
9.
盘鮈属鱼类的分类研究及两新种记述(鲤形目:鲤科) 总被引:2,自引:2,他引:0
盘鮈属是我国鲤科鱼类的一个特有属,过去已记录7种,因早期发表的云南盘鮈原始描述简略,国内又无人察看过模式标本,造成一些种名归属混乱。本工作在核对多数种的模式标木或地模标本的基础上,对盘鮈属鱼类的分类性状重新估价,认为多鳞盘鮈 D.polylepis Huang不能成立,为长鳔盘鮈 D.macrophysallidos Huang的同物异名,予以归并,经整理本属鱼类可分为8个种,其中具2个新种,文中给出了分种检索表,还就过去分类中存在的其他问题进行了讨论。 相似文献
10.
Conservation status, identification, distribution, abundance, habitat and ecology, conservation actions and recommendations
of a endemic cyprinid fish, Cyprinus micristius were introduced based on data and knowledge from a GEF project in Lake Dianchi, Yunnan, China. 相似文献