4种生态因子对虎斑乌贼幼体生长与存活的影响

旨在研究温度、盐度、饵料种类、投饵量对虎斑乌贼（Sepia pharaonis）幼体生长与存活率的影响,以确定其生长发育的最佳生态条件,为人工育苗提供理论依据。在室内控制条件下,采用单因子试验研究了不同温度（18、21、24、27、30和33℃）、不同盐度（18、21、24、27、30和33）、不同饵料种类（虾糜、活糠虾、卤虫无节幼体、桡足类、死糠虾、虾糜＋强化卤虫后无节幼体、强化卤虫后无节幼体）、活糠虾不同投饵量（0、2、4、6、8和10 g/d）对虎斑乌贼幼体生长发育的影响。结果显示：不同温度对虎斑乌贼幼体生长影响显著（P〈0.05）,最适温度为24-27℃,在最适温度下,存活率为84.4%-91.1%,特定生长率为4.82%-6.13%,存活率（y）与温度（x）的函数关系为y=-0.15x3＋30.637x-447.002（r2=0.923）。幼体适宜盐度为24-33,最适盐度为27,在最适盐度条件下,其存活率为（90.0±5.29）%,特定生长率为（3.71±0.34）%。投喂7种开口饵料,以活糠虾效果最佳,存活率为（96.7±2.94）%,特定生长率为（3.77±0.23）%;强化卤虫后无节幼体效果次之,存活率为（95.6±2.31）%,特定生长率为（2.54±0.15）%,其余各组培养效果均不理想。投喂活糠虾,随着投饵量的增加,其存活率随之提高,摄食量（y）与个体重（x）的回归方程为y=0.227x-0.063（r2=0.921）。     

湖北省钟祥市粘虫发生规律研究

为了明确粘虫Mythimna separata(Walker)在湖北省钟祥市的发生规律,对小麦玉米轮作田粘虫成虫和幼虫种群的发生动态、粘虫雌蛾卵巢发育进度以及粘虫越冬虫量作了调查,分析了粘虫种群虫源性质。结果表明,钟祥市为1代粘虫多发区,其虫源为外地迁入的越冬代成虫,1代粘虫危害高峰期在4月中下旬,羽化盛期在5月中下旬,羽化后以迁出为主。第2代粘虫发生量很小,羽化后基本全部迁出;在田间未调查到第3代粘虫幼虫,本区发现的第3代成虫可能为由北方南迁的过境种群;第4代粘虫发生量也很小,羽化后全部迁出,不在本区繁殖危害。在田间未调查到准备越冬的粘虫。     

Faecal case architecture in the gibbosus species group of Neochlamisus Karren, 1972 (Coleoptera: Chrysomelidae: Cryptocephalinae: Chlamisini)

Constructions composed of faeces are rare in insects, but occur in certain leaf-beetle clades. Members of the subfamily Cryptocephalinae share a complex behavioural and morphological synapomorphy, involving portable faecal cases that house the immature stages. A maternally initiated egg case is expanded and enlarged through four larval stadia, then sealed to provide a pupal chamber from which adults eventually emerge. We analyse and compare faecal-case architecture in ten taxa of the cryptocephaline genus Neochlamisus , and assess structural variation within a life cycle, between different 'host forms' of Neochlamisus bebbianae , and among species. These cases proved to be comprised primarily of faeces, with plant trichomes representing the only common secondary component. General architectural trends reflected variation in shape, faecal texture, and the incorporation and density of trichomes. Deviations of the Neochlamisus case from a simple geometrical gnomon reflect the changing body size of the animal, differential application of faeces, and shifts in the orientation of the carriage of the case. Neochlamisus cases are presumably energetically costly to produce, carry, and maintain, and some adaptive hypotheses of case evolution are proposed. Additionally, literature on case morphology in other camptosomates is reviewed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 315–351.     

光周期对中华通草蛉自然越冬成虫及实验种群幼虫耐寒能力的影响

【目的】滞育诱导期进行短光照处理可影响昆虫耐寒性。为明确光周期对中华通草蛉Chrysoperla sinica (Tjeder)耐寒性的影响, 针对中华通草蛉滞育解除过程及非滞育虫态的耐寒性进行了一系列研究。【方法】测定了中华通草蛉自然越冬成虫的过冷却点（supercooling point, SCP）以及长光周期（15L∶9D）和短光周期（9L∶15D）条件下自然越冬成虫在滞育解除过程中在-12℃下的死亡率, 并测定了室内长、 短两种光周期下实验种群2龄和3龄幼虫的过冷却点（SCP）、 结冰点（freezing point, FP）以及-7℃下的死亡率。【结果】中华通草蛉12月份的自然越冬成虫SCP集中在-10~-14℃之间。SCP低于-12℃的个体占43.70%, 且-12℃处理1 d死亡率为62.00%。-12℃处理1 d条件下的长、 短光周期处理自然越冬成虫, 除处理0 d外, 长光周期处理死亡率均高于短光周期处理的, 且在处理15 （P=0.012）, 20 （P=0.01）和25 d （P=0.001）差异显著。中华通草蛉试验种群相同龄期幼虫在短光周期下的SCP和FP均高于长光周期下, 但差异不显著(P>0.05); 但在-7℃下, 2龄幼虫短光周期下的低温死亡率为67.00%±4.04%, 显著低于长光周期下的低温死亡率（78.00%±1.33%）（P=0.011）, 3龄幼虫短光周期条件下低温死亡率为24.33%±1.33%, 显著低于长光周期下的低温死亡率（53.00%±3.46%）（P=0.002）。【结论】中华通草蛉为结冰敏感型, 诱导滞育的短光照处理可提高其幼虫期及滞育解除过程中成虫的耐寒能力。     

Timing and size of blooms of the ctenophore Mnemiopsis leidyi in relation to temperature in Narragansett Bay, RI

The ctenophore Mnemiopsis leidyi is at the northern extreme of its geographic range in Narragansett Bay, an estuary on the northeast coast of the United States. Blooms have typically been observed in late summer and fall according to records from 1950 to 1979. We document an expansion of the seasonal range of this important planktonic predator to include springtime blooms during the 1980s and 1990s. This shift to an earlier seasonal maximum is associated with increasing water temperature in Narragansett Bay. Temperatures in spring have risen, on average, 2 °C from 1950 to 1999 with warm years being associated with the positive phase of the North Atlantic Oscillation. During 1999, M. leidyi appeared earlier in spring and was more abundant than during any previous year for which records are available. Changes in the seasonal pattern and abundance of this predator are likely to have important effects on planktonic ecosystem dynamics of Narragansett Bay. These include reduction of zooplankton abundance in spring followed by increases in size and frequency of summer phytoplankton blooms. Earlier blooms of M. leidyi may also reduce survival of eggs and larvae of fish because, as in 1999, they coincide with the period of peak spawning.     

使用冷冻方法防治昆虫标本虫害

皮蠹幼虫对昆虫标本的蛀蚀是我国北方地区标本保藏时需要注意的首要问题。经12次的试验观察表明,花斑皮蠹幼虫TrogodermavariabileBallion在冰柜中放置位置不同其冷冻致死率亦不相同置于冰柜表层的,死亡率介于0～50%;上层的死亡率为95%～100%;中上层及中层死亡率达100%。放置在表层及上层的皮蠹幼虫,在经2d以上的冷冻处理后部分个体出现复活。因此,对那些原先放置上层及表层的标本,第1次冷冻结束后,间隔数天应再进行第2次冷冻,以提高和巩固冷冻杀虫效果。经3年的实践证明,采用冷冻方法治理皮蠹幼虫为害效果明显,可以推广普及。     

Ontogenetic changes in spot configuration (numbers,circularity, size and asymmetry) and lateral line in Neurergus microspilotus (Caudata: Salamandridae)

Coloration in three of four species of the genus Neurergus including N. microspilotus is characterized by the presence of yellow spots on a dark skin, but there is no available information about changes in spot configuration, speed of development and degree of association between melanophore‐free region and the lateral line. In this study, spot numbers, spot circularity, spot size and spot asymmetry were studied during larval to adult growth in N. microspilotus during July 2012 to June 2015. The mean numbers of spots increased during the late larval stage till postmetamorphic period from 13.33 ± 3.77 to 22.53 ± 4.09 and reached 42.62 ± 4.06 in adults. At the same time, the extent of spots gradually decreased in size from 5.80 ± 1.00 to 3.57 ± 0.97 mm² and reached 3.55 ± 1.42 mm² in adults, but the spot circularity increased from 0.48 ± 0.23 to 0.78 ± 0.49 and reached 0.80 ± 0.15 in adults. In adults, the numbers, circularity, size and asymmetry of spots remain stable with little but non‐significant changes during the study period. Histological study shows that formation of a melanophore‐free region correlates with the development of the lateral line receptors. This study demonstrates that the effects of lateral line on chromatophores persist through middle larval stages but diminish as metamorphosis completes.     

Distribution of ichthyoplankton in the eastern Peter the Great Bay,Sea of Japan,in June and July of 2007

Comparison of the results of ichthyoplankton surveys conducted at 97 stations in the eastern part of the Peter the Great Bay of the Sea of Japan, in June–July 2007 with the similar research data of the 1950s shows that at present, as was the case 50 years ago, flatfish eggs belonging mainly to the yellowfin sole Limanda aspera and brown sole Pleuronectes herzensteini prevail in the local ichthyoplankton (up to 86%). The highest concentrations of these species’ eggs were recorded in the Vostok Bay and Strelok Bay. The spawning activity of flatfish in 2007 is found to be lower than in the mid 1900s, but the significance of the eastern part of the Peter the Great Bay for flatfish reproduction remains large. The importance of long-term monitoring in this area, which is being subjected to steadily growing anthropogenic impacts, is also proven.     

Temperature and the biology and predation of Ilione albiseta (Diptera: Sciomyzidae) — Potential biological control agent of liver fluke

The effect of temperature on predation by Ilione albiseta (Diptera: Sciomyzidae) on Lymnaea peregra was investigated at 14°, 17°, 20°, 23° and 26°C. The mean dry weight of snail tissue (Lymnaea peregra) attacked and consumed per day by first and second instar I. albiseta larvae was highest at 20°C while for third instar and total larval duration period it was greatest at 23°C. The mean number of snails killed per day during the third instar was also highest at 23°C. The total amount of snail tissue consumed by I. albiseta larvae increased significantly from first to second instar and from second to third instar at each constant temperature. Mean survival period of unfed first instar larvae decreased from 28.4 days at 14°C to 11 days at 26°C and the mean length of the second instar cephalopharyngeal skeleton decreased with increasing temperatures. As temperature increased the rate of consumption of oxygen (dissolved in water) by first and third instar larvae rose.     

Survival, growth and feeding of vendace, Coregonus albula (L.), larvae in net enclosures

Vendace, Coregonus albula (L.), larvae reared in net enclosures anchored in the littoral zone of Lake Ylä-Enonvesi, eastern Finland, were observed for a period of 44 days in order to determine the effects of density on mortality, growth and feeding of the larvae. The ratio of newly-hatched fish to their food was regulated by controlling the number of fish stocked into the enclosures. Prey animals were expected to move freely in and out of the enclosures. The effect of nylon mesh (500 μm) on the penetration of zooplankters into the enclosures was negligible. The influence of possible starvation was determined by analysing the growth of the larvae, their Fulton condition factor, the instantaneous amount of food ingested, and the food composition in their guts. All these indicators were inversely correlated with larval density. Vendace larvae were found to be resistant to mortality from direct starvation. At all densities the survival rate was over 60%. At the time of complete yolk absorption, there was no increase in mortality.