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121.
Discrimination through silk recognition: The case of the two-spotted spider mite Tetranychus urticae
G Clotuche JL Deneubourg AC Mailleux C Detrain T Hance 《Comptes rendus biologies》2012,335(8):535-540
Choosing a suitable habitat is a main step in the settlement process, particularly for species having weak movement abilities. Reliable cues are thus needed for habitat selection. In silk-spinning arthropods, silk can be used as a social cue to select an appropriate location. Silk can also provide information on the presence of related or non-related individuals. In this article, we compare the settlement behaviour of two strains of the two-spotted spider mite, Tetranychus urticae, in response to the presence of silk woven by an individual of its own or another strain. We then examined how individuals behaved when confronted with both types of silk (own/another strain) simultaneously. Both strains were sensitive to related silk. Settlement decision for both strains did not differ according to the origin of the silk. Mites used the silk as a communication cue for habitat selection and strain discrimination. Our results provide experimental evidence for the use of multiple social cues in the settlement decision by weaving mites. 相似文献
122.
记述了采自中国重庆洞穴内的球体蛛科喀蛛属1新种,心形喀蛛Karstia cordata sp.nov.,模式标本保存在四川大学自然博物馆(SCUM).心形喀蛛,新种Karstia cordata sp.nov.(图1~18)新种与上扬子喀蛛K.upperyangtzica Chen,2010相似,但它们的区别在于:前者具1插入器附片,后者缺失;前者插入器突不分叉,后者多分叉;前者中突表面呈具细齿锉刀状,后者光滑;前者雌性生殖板呈心形,后者为近三角形,前者纳精囊宽且长,后者窄而短.正模♂,产自中国重庆市武隆县土地乡天生村硝洞(29.53°N,107.85°E;海拔1050 m),2010-10-17.副模:1 ♂,3♀ ♀,采集信息同正模;2 ♂♂,10♀ ♀,产自四川省华蓥市洋河镇盐井沟村垛子石洞(30.29°N,106.77°E),2010-10-16,均为林玉成和窦亮采集.词源:新种种名源自拉丁词语cordatus(心形的),意指该种雌性生殖板形状;形容词. 相似文献
123.
据作者调查和文献报道,本文列出了江西产90种园蛛在江西、中国和全球的地理分布;在世界动物地理区划水平上,江西园蛛主要由东洋界以及东洋界和古北界成分组成;在中国动物地理区划水平上,江西园蛛主要由华中区,华中区+华南区+西南区以及华中区+西南区跨界成分组成;与国内23省(区)区系组成比较,江西园蛛与湖南的共有种最多,与西藏共有种最少;文章最后分析了江西园蛛物种结构的特点. 相似文献
124.
Spiders have recently emerged as important diversity hot spots for endosymbiotic bacteria, but the consequences of these symbiotic interactions are largely unknown. In this article, we examined the evolutionary history and effect of the intracellular bacterium Cardinium hertigii in the marbled cellar spider Holocnemus pluchei. We showed that Cardinium infection is primarily transmitted in spider populations maternally via egg cytoplasm, with 100% of the progeny from infected mothers being also infected. Examination of a co‐inherited marker, mitochondrial DNA (mtDNA), revealed that Cardinium infection is associated with a wide diversity of mtDNA haplotypes, showing that the interaction between Cardinium and H. pluchei has a long‐term evolutionary dimension and that horizontal transmission among individuals could also occur. Although Cardinium is well known to exert sex ratio distortion or cytoplasmic incompatibility in various arthropod hosts, we show, however, that Cardinium does not interact with the reproductive biology of H. pluchei. A field survey shows a clear geographical structuring of Cardinium infection, with a marked gradual variation of infection frequencies from ca. 0.80 to 0. We discuss different mechanistic and evolutionary explanations for these results as well as their consequences for spider phenotypes. Notably, we suggest that Cardinium can either behave as a neutral cytoplasmic element within H. pluchei or exhibit a context‐dependent effect, depending on the environmental conditions. 相似文献
125.
SEAN J. BLAMIRES DIETER F. HOCHULI MICHAEL B. THOMPSON 《Biological journal of the Linnean Society. Linnean Society of London》2008,94(2):221-229
An effective visual signal elicits a strong receiver response. The visual receptors of most insects are sensitive to ultraviolet (UV), blue and green light. The decorations of certain orb web spiders may be described as a type of visual signal, a sensory trap, as they exploit visual biases in insects. We filtered UV and blue light from the decorations of Argiope keyserlingi , under field conditions, using plastic sheets to test if the UV and blue light reflected affects the type of prey caught. We found that houseflies, blowflies, stingless bees, honeybees and vespid wasps were caught more frequently in webs with decorations than webs without, while ichneumonid wasps were caught less frequently. Blowflies, stingless bees, honeybees and vespid wasps were caught more often in unfiltered decorated webs. These insects also have receptor sensitivities in the blue and UV. We showed that exploiting visual sensory biases plays an integral role in attracting insects to orb web decorations. Whether UV light, blue light, or both, are the most important cue, however, requires further study. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 221–229. 相似文献
126.
Gibb H Hilszczański J Hjältén J Danell K Ball JP Pettersson RB Alinvi O 《Oecologia》2008,155(1):63-74
Species belonging to higher trophic levels are particularly vulnerable to habitat loss and consequential host population declines,
but detection of effects depends on observation scale. We investigated the effects of habitat and host availability at multiple
scales on parasitoids of early successional saproxylic beetles in middle boreal Sweden, where forestry has led to habitat
fragmentation and coarse woody debris (CWD) loss. Parasitoid wasps and beetle hosts were collected from nine locations, each
containing three spruce-dominated stand types (clear-cut, mature managed and unmanaged stands), using emergence traps on experimental
CWD. We measured local CWD volumes and determined the availability of forests of a suitable age within the landscape. We tested
parasitoid responses to stand type, CWD volume, abundance of known and probable hosts and longitude. Additionally, we tested
whether parasitoids responded to the area of habitat of a suitable age within radii from 0.2 to 10 km. Stand type appeared
in best-fit models for all common species, suggesting that wasps respond strongly to habitat at local scales. Longitude (largely
climate) featured commonly, but CWD volume was never significant. Host abundance appeared in best-fit models for three of
five common species, proving significant only for Bracon obscurator, the abundance of which correlated with that of Orthotomicus laricis at both trap and site levels. Rhimphoctona spp. also correlated significantly with its known host Tetropium castaneum at the trap level. B. obscurator responded to habitat area at scales of 0.6–1 km and Cosmophorus regius responded at radii greater than 7 km, while the larger species did not respond strongly to habitat area. The role of habitat
area at greater scales thus varied greatly amongst species, but our data suggest that dispersal of these common early successional
species may not be strongly restricted at the current scale of fragmentation of their boreal habitats. 相似文献
127.
Laska M Persson Suorra J Bautista RM Hernandez Salazar LT 《American journal of primatology》2008,70(9):839-847
The purpose of this study was to determine taste difference thresholds for monosodium glutamate (MSG) and sodium chloride (NaCl) in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi). Using a two-bottle preference test of brief duration, three animals of each species were presented with four different reference concentrations of 50, 100, 200, and 400 mM of a tastant and tested for their ability to discriminate these from lower concentrations of the same tastant. The just noticeable differences (JNDs), expressed as Weber ratios (DeltaI/I), were found to range from 0.1 to 0.5 for MSG and 0.2 to 0.45 for NaCl in the pigtail macaques, with a significant tendency for higher Weber ratios with higher reference concentrations. In the spider monkeys, JNDs ranged from 0.15 to 0.4 for MSG and 0.1 to 0.25 for NaCl, with Weber ratios staying fairly constant across the reference concentrations tested. Thus, the JNDs were found to be generally similar in both species and to be at least as low as those found in humans for MSG and NaCl, as well as those found in spider monkeys for sucrose. The results support the assumption that both pigtail macaques and spider monkeys may use differences in perceived intensity of MSG and NaCl as a criterion for food selection. 相似文献
128.
Gibson KN Vick LG Palma AC Carrasco FM Taub D Ramos-Fernández G 《American journal of primatology》2008,70(5):485-489
We describe two cases of infanticide, two suspected infanticides, and a forced copulation by familiar resident males in two populations of wild spider monkeys (Ateles belzebuth chamek and A. geoffroyi yucatanensis). These are the first known infanticides and forced copulation in spider monkeys. Data were gathered from four neighboring communities of spider monkeys in Manu National Park at the Cocha Cashu Biological Station, Peru and two communities in the Otoch Ma'ax Yetel Kooh Reserve at Punta Laguna, Mexico, during intensive field studies of over 2,000 hr each. These are rare behaviors, but results suggest that mating history and sexual coercion are important in spider monkey social relationships. 相似文献
129.
Myung-Jin MOON 《Entomological Research》2008,38(2):149-156
The microstructural characteristics of the silk‐spinning apparatus and its ecological significance in the coelotine spider Paracoelotes spinivulva were examined by field emission scanning electron microscopy, with the goal of understanding the properties and the evolutionary origins of these silk constructs. The silk apparatuses of this spider were composed of four basic types of silk‐spinning spigot (ampullate, pyriform, aciniform and tubuliform), which connected with typical silk glands in the abdominal cavity. Of the three pairs of spinnerets, the posterior pairs were highly elongated along the body axis. Anterior spinnerets comprised two pairs of ampullate glands and approximately 70–80 pairs of pyriform glands in both sexes. Middle spinnerets had one to two pairs of ampullate spigots, three pairs of tubuliform spigots in females, and 50–60 (female) or 80–90 (male) pairs of aciniform spigots. An additional two pairs of tubuliform spigots in females and 70–80 (female) or 100–120 (male) pairs of aciniform spigots were counted on the spinning surfaces of the posterior spinnerets in both sexes. Although the coelotine spiders use their silk to catch prey, P. spinivulva characteristically do not have a typical “triad” spigot, including a flagelliform and two aggregate spigots, for capture thread production. 相似文献
130.
Snowdrop (Galanthus nivalis) lectin has previously been shown to have anti-feedant and insecticidal activity towards sap-sucking insects. However, its effectiveness against plant-parasitic mites has not been demonstrated. In this study, the commercial papaya (Carica papaya L.) cultivar Kapoho, which is highly susceptible to mites, was transformed with the snowdrop lectin (G. nivalis agglutin [GNA]) gene. Polymerase chain reaction confirmed the presence of the transgene and six independent transformed lines were selected for expression analysis. Western blot analysis showed that the lines expressed a recombinant protein with a molecular weight similar to that of the native snowdrop lectin. Leaf extracts containing the recombinant GNA protein agglutinated trypsinized rabbit erythrocytes thus, showing the GNA protein to be biologically active. ELISA and indirect measurement from the agglutination assay showed there to be variation in GNA expression among the lines produced. A laboratory bioassay using carmine spider mites (Tetranychus cinnabarinus) suggested improved pest resistance in the transgenic papaya plants. This is the first report that a transgenic plant expressing the GNA gene possesses enhanced resistance to a plant-parasitic mite. 相似文献