四方蒿的化学成分

从唇形科植物四方蒿（Elsholtzia blanda (Benth.)Benth.)中分离得到9个化合物,用光谱分析、化学方法及与已知化合物对照,分别鉴定为：5,6－二氢－6－苯乙类吡喃－2酮（1）、木栓桐（2）、4－羟基－3－甲氧基苯乙烯（3）、5,2′－二甲氧基－6,7－二氧亚甲基双氢黄酮（4）、5－羟基07－甲氧基－6－O[α－L－鼠李糖（1→2）－β－D－岩藻糖]黄桐甙（5）,5,5′－二羟基－7－乙酰氧基6,8,3″,3″－四甲基吡喃（3′,4′）黄酮（6）、5,5′－二羟基－5－（α－甲基）丁酰氧基－6,8,3″,3″－四甲基吡喃（3′,4′）黄酮（7）、5,5′－二羟基－6,7－二氧亚甲基－8,3″,3″－三甲基吡喃（3′,4′）黄酮（8）和丁香酸葡萄糖甙（9）。其中,6、7、8为新化合物,分别命名为四方蒿素Ⅰ、Ⅱ和Ⅲ。     

不同体重肩斑银鳞蛛和大腹园蛛圆网的结构特征

对在自然条件下不同体重肩斑银鳞蛛Leucauge blanda和大腹园蛛Araneus ventricosus所织圆网的结构特征进行测量研究.结果表明:体重小于35.1 mg的肩斑银鳞蛛所织圆网的捕丝长度、捕食面面积、捕丝间距和半径丝根数均与个体体重呈显著正相关,而体重大于35.1 mg的个体中,这种关系并不显著,但其圆网的上、下部捕丝长度比与体重呈显著负相关,即圆网随个体的体重增加而表现出更强的不对称性;体重小于144.9 mg的大腹园蛛所织圆网的捕丝长度和捕食面面积均与个体体重呈显著正相关,体重小于103.8 mg的大腹园蛛所织圆网的半径丝根数与个体体重呈显著正相关,而大于这一体重分界值的个体中,这种关系同样不显著.大腹园蛛圆网的平均捕丝间距与体重未呈现出相关关系,体重大于85.4 mg的个体中,其网的上、下部捕丝长度比与体重呈显著负相关.两种蜘蛛圆网结构特征的变化及圆网结构特征与个体体重关系变化的不同体重分界值,可能反映了它们在不同生境下不同生长阶段的捕食投入与捕食策略.     

3种中型蜘蛛卵袋形态特征与纤维组成结构

采用扫描电镜和氨基酸自动分析仪对球蛛科(Theridiidae)温室拟肥腹蛛(Parasteatodatepidariorum)、肖蛸蛛科(Tetragnathidae)肩斑银鳞蛛(Leucauge blanda)及狼蛛科(Lycosidae)猴马蛛(Hippasa holmerae)3种中型蜘蛛卵袋的超微结构和氨基酸组成进行了观察。形态观察表明,这3种蜘蛛的卵袋形态各异,温室拟肥腹蛛卵袋一头尖,呈梨状;肩斑银鳞蛛卵袋呈扁平状;猴马蛛卵袋呈椭球形。扫描电镜观察表明,温室拟肥腹蛛卵袋外覆盖层仅仅由一种均一直径的柱状腺丝组成,而另外2种蜘蛛卵袋外覆盖层主要由柱状腺丝与少量其他丝腺纺出的丝纤维组成。氨基酸组成分析表明,温室拟肥腹蛛卵袋外覆盖层的丝纤维的氨基酸组成与具有保守性的其他种类蜘蛛柱状腺丝心蛋白的氨基酸组成差异较大,这表明其可能含有新的丝心蛋白家族成员。本文根据氨基酸组成与扫描电镜的结果分析探讨了不同直径丝纤维的丝腺来源。     

Function of being colorful in web spiders: attracting prey or camouflaging oneself?

Bright body colorations of orb-weaving spiders have been hypothesizedto be attractive to insects and thus function to increase foragingsuccess. However, the color signals of these spiders are alsoconsidered to be similar to those of the vegetation background,and thus the colorations function to camouflage the spiders.In this study, we evaluated these 2 hypotheses by field experimentsand by quantifying the spiders' visibility to insects. We firstcompared the insect interception rates of orbs constructed bythe orchid spider, Leucauge magnifica, with and without thespider. Orbs with spiders intercepted significantly more insectsthan orbs without. Such a result supported the prey attractionbut not the camouflaging hypothesis. We then tested whetherbright body colorations were responsible for L. magnifica'sattractiveness to insects by manipulating the spiders' colorsignals with paint. Alteration of color signals significantlyreduced L. magnifica's insect interception and consumption rates,indicating that these spiders' bright body parts were attractiveto insects. Congruent with the finding of field manipulationswere the color contrasts of various body parts of these spiders.When viewed against the vegetation background, the green bodyparts were lower, but the bright parts were significantly higherthan the discrimination threshold. Results of this study thusprovide direct evidence that bright body colorations of orbweavers function as visual lures to attract insects.     

鸡肝散的引种和精油成分初步分析

鸡肝散(Elsholtzia blanda)种子在低温9℃左右,密藏24个月以上,种子发芽率仍可保持87％。种子从发芽生长至枯黄止,整个生育期为8—9个月。栽培植株精油含量随着生长发育日趋成熟而逐渐增加,为0.42—0.88％,主要成分芳樟醇、1,8-桉油素、苯乙酮、反-氧化芳樟醇、樟脑、龙脑等的含量,有一定的变化规律,其它成分含量变化差异较小。     

Memory of distances and directions moved as cues during temporary spiral construction in the spiderLeucauge mariana (Araneae: Araneidae)

The spider Leucauge marianaprobably uses the presence of temporary spiral (TSP) lines already in place to determine sites of attachment of currently produced loops of temporary spiral, but less rigidly than has been previously supposed for orb weavers. Memory of distances and directions traveled recently to and from TSP lines is implicated by the fact that adjustments to experimental and natural discontinuities in previous TSP lines occur gradually rather than being abrupt. Distances and directions traveled along both radii and previous TSP lines correlate with relative amounts of adjustment. Body size may also be used as a reference measure, but not in the simple, inflexible way suggested by R. W. G. Hingston (A Naturalist in Himalaya,Small, Maynard, Boston, 1920). Tensions on radii are not used as cues in any simple way, and may not be used at all, since experimental changes in tensions produced effects consistent with resulting changes in thread positions but inconsistent with tension differences.     

中国银鳞蛛属1新纪录种(蜘蛛目:肖蛸科)

肖蛸科Tetragnathidae银鳞蛛属Leucauge在我国陕西省采到2种。其中近蕾银鳞蛛Leucauge sebgemmea Boes.& Str。,1906系我国1新纪录种。