三突花蛛对小菜蛾幼虫的捕食效应

本文研究三突花蛛对小菜蛾幼虫的捕食功能反应及干扰因素对捕食作用的影响。结果表明,三突花蛛对小菜蛾幼诉捕食效应属ＨｏｌｌｉｎｇⅡ型反应,捕食作用率随捕食者－猪物比率上升而下降,雌蛛的捕食效应强于雄蛛。     

三突花蛛对小菜蛾幼虫的捕食效应

本文研究三突花蛛对小菜蛾幼虫的捕食功能反应及干扰因素对捕食作用的影响。结果表明,三突花蛛对小菜蛾幼虫的捕食效应属HollingⅡ型反应,捕食作用率随捕食者-猎物比率上升而下降,雌蛛的捕食效应强于雄蛛。     

三突花蛛有效活动的初步研究

提出了一个综合评价动物有效活动行为的指标——有效活动时间,研究了三突花蛛在不同温度条件下的有效活动时间。结果表明,在4种实验温度(5、15、25、35℃)条件下,三突花蛛的有效活动时间有极显著差异。(1)在4种实验温度条件下,蜘蛛的有效活动时间与蜘蛛的身体长度、身体重量、体重体长比无显著关系;(2)在温度为15、25℃条件下,雌蛛与雄蛛的有效活动时间无显著差异,而在温度为5、35℃条件下,雌蛛的有效活动时间显著低于雄蛛;(3)在4种温度条件下,无斑雌蛛的有效活动时间与有斑雌蛛没有显著差异;(4)在4种实验温度条件下,分别对不同性别的三突花蛛的有效活动时间进行方差分析,结果表明,4种实验温度条件下,三突花蛛雄蛛、雌蛛有效活动时间有极显著的差异。     

温度对三突花蛛个体发育和生殖行为的影响

本研究结果表明:(1)三突花蛛(Misumenops tricuspidatus)的卵在35℃恒温条件下不能孵化。(2)在15°-32℃恒温条件下随温度升高历期逐渐缩短,脱皮次数也随之减少,以25°-30℃恒温条件下幼蛛的存活率较高;同一温度梯度下雄蛛的平均历期均短于雌蛛。(3)在28℃恒温条件下产卵率为最高,产卵量最高;25℃下孵化率最高,30℃下生育力最强。(4)三突花蛛在繁殖力上具有种的稳定性。     

三突花蛛在落叶松人工林内生物学及作用的初步研究

三突花蛛在东北地区一年一代、越冬龄期不整齐。在落叶松林内，早春上树捕食害虫，６月中旬后，下迁至林下的灌木丛和草上，在植物叶上做囊产卵，该幼蛛自孵化起至越冬前，不再主动向高树冠部迁移，而仅在灌木、草上及小树上活动，三突花蛛能捕食多种木害虫，在早春，其种群密度往往高于其它害虫天敌，是一种极有利用前途的天敌。     

三突花蛛对茶小绿叶蝉的捕食作用及其模拟模型的研究

在室内条件下,测定结果表明三突花株亚成蛛对茶小绿叶蝉若虫及成虫的日捕食量分别为１８．３头／ｄ,１７．３头／ｄ,对成虫的功能反应曲线可用ＨＯｌｌｎｇ圆盘方程模拟：Ｎａ＝１．０５５８６Ｎｔ／（１＋０．０１３６５／Ｎｔ）自身密度反应用Ｈａｓｓｅｌ－Ｖａｒｌｅｙ模型拟合,Ｅ＝０．５１７Ｐ＾－０．６５６７,经Ｘ＾２检验,以上各方程理论值与实际值误差不显著（〈Ｐ０．１０）。温度（Ｔ）对功能反应的影响可用以下方     

油菜田三突花蛛的生物学特性初报

通过大田观察和室内饲养,发现武汉地区油菜田三突花蛛3月中旬开始出来活动,4月中旬达到高峰期,主要隐蔽于曲菜花丛中,以待猎物到来,不结网,有飞航习性,数量达225头/百株,占总捕食性天敌的82％,同时开始交配、产卵。不仅与蚜虫、叶蝉的发生正相关,也和油菜的长势呈现正相关性,并对害虫起到明显的控制作用。可见,是油菜田害虫的重要天敌。     

三突花蛛对桃蚜和桃粉蚜选择效应研究

三突花蛛是桃树上早春2种重要害虫桃蚜和桃粉蚜的主要天敌。对这2种害虫的捕食喜欢程度,受害虫种群密度的变化而变化。在二者等密度增加时,其捕食喜好程度相近;在桃蚜数量明显增加时,喜食桃蚜;在桃蚜数量剧增时,当两者密度值在50:50以下,喜食桃蚜,高于此值,则喜食桃粉蚜。     

食物以三突花蛛生长发育的影响：Ⅱ.食物对三突花蛛营养指标的影响

研究不同食物对三突花蛛相对生长率（ＲＧＲ）、相对取食量（ＲＣＲ）、食物利用率（ＥＣＩ）的影响。结果表明,三突花蛛各龄相对生长率以取食混合食物为高,取食单一食为低。各龄相对取食量对棉铃虫和果蝇较高,对摇纹则较低,食物利用率则以对摇蚊的利用率为最高,对棉铃虫和果蝇的利用率较低。     

Spinneret Microstructure of the Silk Spinning Apparatus in the Crab Spider, Misumenops tricuspidatus (Araneae: Thomisidae)

The silk spinning apparatus in the crab spider, Misumenops tricuspidatus was studied with the field emission scanning electron microscope (FESEM) and the main microstructural characteristics of the silk glands are presented. In spite of the fact that the crab spiders do not spin webs to trap a prey, they also have silk apparatus even though the functions are not fully defined. The crab spider, Misumenops tricuspidatus possesses only three types of silk glands which connected through the typical spinning tubes on the spinnerets. The spinning apparatus of Misumenops closely corresponds to that of wandering spiders such as jumping spiders or wolf spiders except some local variations. Anterior spinnerets comprise 2 pairs of the ampullates and 48 (±5) pairs of pyriform glands. Another 2 pairs of ampullate glands and nearly 20 (±3) pairs of aciniform glands were connected on the middle spinnerets. Additional 50 (±5) pairs of the aciniform glands were connected on the posterior spinnerets. The aggregate glands and the flagelliform glands which have the function of sticky capture thread production in orb‐web spiders as well as the tubuliform glands for cocoon production in females were not developed at both sexes of this spider, characteristically.     

The combined effects of temperature and diet on development and survival of a crab spider,Misumenops tricuspidatus (Fabricius) (Araneae: Thomisidae)

In the present study, the combined effects of temperature and diet on development and survival of a crab spider, Misumenops tricuspidatus (Fabricius) (Araneae: Thomisidae) in laboratory conditions were investigated. The experiments were carried out at five constant temperatures ranging from 15°C to 35°C on two kinds of diets, fruit flies (Drosophila melanogaster) and a mixed diet of fruit flies and dung flies. It was found that development rate of eggs increased with successive temperature increments, reaching a maximum at 30°C, then declined at 32°C and that eggs survived well between 20°C and 30°C (>70%), but no eggs survived to hatching at 35°C regardless of whether the spiders were fed on single or mixed diet. Juveniles completed development on both diets at all constant temperatures tested, but survival was low at the extreme temperatures. Juvenile development times decreased over successive temperature increments up to 30°C, then increased at 32°C. Females developed faster than males. Diet also influenced development time, survival and number of moults to reach maturity. Juveniles raised on the mixed diet composed of fruit flies and dung flies developed faster, survived better, and required fewer moults to reach maturity than on a diet composed of only fruit flies. Plots of development rates (reciprocal of mean development times) and survival rates (expressed as percentages) against constant temperatures indicated that M. tricuspidatus is well adapted to low temperatures, but detrimentally affected by high temperatures. Using linear regression, the lower development threshold (LDT) and the sum of effective temperatures (SET) for all life stages of M. tricuspidatus on each diet were estimated. LDT and SET varied among developmental stages and between diets.     

Feeding preferences of the spider Misumenops pallidus (Araneae: Thomisidae) on potential prey insects from alfalfa crops

The spider Misumenops pallidus (Thomisidae) is commonly found in alfalfa crops. We studied its predatory preferences on potential insect prey, particularly regarding agroecosystems pests. Two kinds of tests were done under normal laboratory conditions: simultaneous presentation of prey (n = 215) and alternative prey test (n = 45). The spiders preferred insects that were mobile, small, without defensive glands and with thin exoskeletons. According to the amount of prey consumed, we established four predation levels: high (> 55%, on adult Drosophila melanogaster flies); intermediate (30%-55% on the defoliator larvae of Rachiplusia nu and adult heteropterans: Horciasinus argentinus and Halticus spegazzinii); and low (10%-30% on the chrysomelids Colapsis sp. and Diabrotica speciosa). The pentatomid Piezodorus guildinii, the curculionid Naupactus sp. and the aphid Acyrthosiphom pisum were not accepted as food. Once the spider captured a prey item it did not accept another, independently of prey item species (82% of trials).     

Factors influencing the evolution of social behaviour in Australian crab spiders (Araneae: Thomisidae)

The social Diaea are non-territorial, periodically-social spiders that do not weave a snare web, a factor considered to be important in spider sociality. Maternal care and heritable retreats are factors common to most group living animals, including social Diaea; suggesting that they are important factors in the evolution of spider sociality. A 4 year survey, along with field and laboratory experiments revealed that mother spiders provided crucial care in the form of a protective Eucalyptus leaf nest and large prey for their offspring. After the mother's death, the nest was inherited and expanded by the offspring. Larger groups built larger, more protective nests, but expended less individual effort doing so, and so survived better than smaller groups.     

Variable Female Mating Positions and Offspring Sex Ratio in the Spider Pityohyphantes phrygianus (Araneae: Linyphiidae)

Chromosomal sex determination and male heterogamety have been thought to seriously impede direct sex ratio control. However, in Pityohyphantes phrygianus, a solitary sheetweb spider with a skewed sex ratio, earlier experimental studies suggested that there are options for female control of offspring sex ratio, if females change their position during the normal mating sequence. Here we show that under natural conditions there is considerable between-female variation in positions, especially after termination of mating. Computer simulations of the orientation of female inner genitalia suggest that sperm are placed in different storage sites depending on the positions adopted. This means that a specific position after mating might potentially influence offspring sex ratio. The variance in offspring sex ratio among females in earlier experiments was binomially distributed, which leads us to conclude that females control the mean sex ratio but do not exercise direct control of the sex of individual offspring.     

中国广西绿蟹蛛属1新种(蜘蛛目:蟹蛛科)

作者在进行中国广西大明山无脊椎动物资源调查研究时,发现了蜘蛛目蟹蛛科绿蟹蛛属1新种,命名为饼绿蟹蛛Oxytate placentiformis sp.nov..所有标本均保存在河北大学生命科学学院.文中测量单位为mm.饼绿蟹蛛,新种Oxytate placentiformis sp.nov.(图1～6)正模♂,广西南宁大明山自然保护区浣纱瀑布,2011-05-23,王英楠采.鉴别特征 在分布于亚洲大陆的本属种类中,本新种与冲绳绿蟹蛛O.hoshizuna Ono,1978,钳绿蟹蛛O.forcipata Zhang&Yin,1998和小头绿蟹蛛O.capitulata Tang&Li,2009外形和触肢器十分相似,但具有以下不同:本种触肢胫节突长,端部弯曲呈"7"字形,而冲绳绿蟹蛛O.hoshizuna的胫节突末端强烈弯曲呈钩状,钳绿蟹蛛O.forcipata胫节突末端呈钳状,小头绿蟹蛛O.capitulata Tang&Li,2009胫节突末端弯曲呈鸟头状.词源学 本新种以雄蛛背甲的形状而拟定.正模 雄蛛体长7.75:头胸部长2.81,宽2.40; 腹部长5.20,宽1.38.背甲黄褐色,中窝纵向线状,颈沟和放射沟不明显; 背甲圆形,头区轻微隆起.8眼2列,背面观两眼列均后凹,后眼列较宽,前侧眼和后侧眼突出; 前中眼直径0.08,前侧眼直径0.10,后中眼直径0.08,后侧眼直径0.10;前中眼距0.13,前中侧眼距0.10,后中眼距0.10,后中侧眼距0.30; 中眼域梯形,前边大于后边(0.30:0.25).螯肢黄褐色,前后齿堤无齿.颚叶黄色,边缘有浓厚的长毛.胸板淡黄色,长大于宽.步足黄褐色,步足测量:Ⅰ 12.40 (3.83+1.38+3.42+2.60+1.17),Ⅱ 12.60 (3.88+1.38+3.57+2.60+1.17),Ⅲ 6.80 (2.09+0.77+1.79+1.33+0.82),Ⅳ7.05 (2.40+0.71+1.79+1.33+0.82); 足式:2143.腹部十分窄长,淡黄色,被有黑色长毛; 腹部背面前端有2对明显的肌痕,腹部后部有横纹,似分节状.触肢胫节腹突拇指状; 外侧突较长,末端骨化程度高,弯曲呈"7"字形状; 生殖球简单,内侧具亚盾板; 插入器刺状,末端较钝.分布:广西.     

剑花蟹蛛的雄性新发现(蜘蛛目:蟹蛛科)

描述了采自中国四川的剑花蟹蛛Xysticus sicus Fox,1937,其雄性系首次发现。标本保存于河北大学博物馆。     

Microstructure of the silk spigots of the green crab spider Oxytate striatipes (Araneae: Thomisidae)

The genus Oxytate L. Koch, 1878 comprises a homogeneous group of nocturnal crab spiders that have silk apparatuses even though they do not spin webs to trap prey. We examined the microstructure of the silk spinning apparatus of the green crab spider Oxytate striatipes, using field emission scanning electron microscopy. The silk glands of the spider were classified into three types: ampullate, pyriform and aciniform. The spigots of these three types of silk gland occur in both sexes. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another two pairs of minor ampullate glands supply the median spinnerets. In addition, the pyriform glands send ductules to the anterior spinnerets (45 pairs in females and 40 pairs in males), and the aciniform glands feed silk into the median (9–12 pairs in females and 7–10 pairs in males) and the posterior (30 pairs in both sexes) spinnerets. The spigot system of O. striatipes is simpler and more primitive than other wandering spiders: even the female spiders possess neither tubuliform glands for cocoon production nor triad spigots for web‐building.