Stegodyphus colonies contain up to a few hundred very highly related. Arachnologische mitteilungen is a journal which focuses on faunistics, ecology, and taxonomy of arachnida excl. Sep 22, 20 the social spider stegodyphus sarasinorum eresidae showed task differentiation significant unequal participation in simulated prey capture events across 10day behavioural assays in the field, independent of developmental stage level of maturation, eliminating age polyethism. Neil gaiman the phrase comes to him before the emotion.
The various aspects of the bionomics and behaviour of this social spider. The sexual biology and morphology of the reproductive organs of stegodyphus sarasinorum karsch araneae. Apr 22, 2019 in the social spider stegodyphus sarasinorum, we examined crosscontextual prey capture behavior of spiders with 2 prey species, namely, honeybees and grasshoppers over the long term 50 days commensurate to adult life spans. Nest circumference ranging from 22 cm to 165 cm of 10 interconnected colonies of a population of stegodyphus sarasinorum was measured. Settepani, v, grinsted, l, granfeldt, j, jensen, j l and bilde, t 20 task specialization in two social spiders, stegodyphus sarasinorum eresidae and anelosimus eximius theridiidae. Normally only one cocoon is made and taken care of by a fertilized female during her lifetime. Social spiders live in large, communal webs, in which they feed communally and cooperate in prey capture, web maintenance and brood care. Comparative female genital morphology in stegodyphus. Individual personalities shape task differentiation in a. Download pdf introduction interspecific competition for resources plays an important role in the evolution of foraging adaptations and the ecological niche of individuals and species, and may. A new study finds that individual anelosimus studiosus spiders do predominantly perform the task they excel at, in line with their individual personality type, when they are.
Oryzias sarasinorum popta, 1905 sarasins buntingi synonymstop. Distribution of social spider stegodyphus sarasinorum along. Body condition and food shapes group dispersal but not. Social stegodyphus spiders are well suited for the study of behavioural adaptations associated with the transition to permanent sociality in spiders, as all three species are. The only reported study from this area on spiders was carried out by palot and balakrishnan, 16 who listed 17 species of spiders from madayipara, a typical lateritic biotope of kavvayi river basin. We collected twenty colonies of stegodyphus sarasinorum karsch, 1892 of varying sizes numbers of resident spiders in and around kuppam 12. Stegodyphus sarasinorum showed behavioural asymmetries at the individual level, that is, individual spiders that had attacked prey once were more likely to attack prey again, independent of their body size or hunger level. Introduction as one of the most widely recognized group of arthropods, spiders make up a diverse portion of the worlds invertebrates. On the habits of indian eresid spiders stegodyphus sarasinorum karsch. Download fulltext pdf observation on a collection of tawny coster acraea terpsicore pieridae. Task specialization in two social spiders, stegodyphus sarasinorum. Stegodyphus sarasinorum karsch, 1891 species india. It is native to india, sri lanka, nepal, and myanmar.
Here we study the linear and nonlinear viscoelastic properties of dragline silk. Stegodyphus sarasinorum, also known as the indian cooperative spider, is a species of spider of the family eresidae. Autecological observations on the indian cooperative spider stegodyphus sarasinorum karsch eresidae. Aug 18, 2014 in social animals, group efficiency is often assumed to increase with task differentiation, but this requires that individuals are better than generalists at the task they specialize in. A new study finds that individual anelosimus studiosus spiders do predominantly perform the task they excel at, in line with their individual personality type, when they are placed in groups. Lepidoptera in the web of the social spider stegodyphus sarasinorum eresidae. In the social spider stegodyphus sarasinorum, collective prey capture is mediated by personality types as a consequence of which some individuals are consistently more likely to attack. These prey species differ in their sizes, risk to spiders and in patterns of struggling when caught on the web. Spider diversity in kavvayi river basin, kerala, southern india. Stegodyphus sarasinorum karsch, 1891 india biodiversity portal. Cocoon care in the social spider stegodyphus dumicola. Article processing charges frequently asked questions download ms word 2003 template download ms word 2007 template researchers guide article pattern process flow publication ethics.
Whole colonies were removed by carefully cutting the branch of the plant which contained their retreats. Males matured before females and had a shorter lifespan than the females. Evidence for loss of nepotism in the evolution of permanent. In the social spider stegodyphus sarasinorum, we distinguish 2 types of dispersal. The genus stegodyphus was established by simon 1873, with the type species s. Distribution of social spider stegodyphus sarasinorum. They are distributed from africa to europe and asia, with two species s. At the last count only 26 of these were regarded as nonterritorial, permanently social species living in shared webs figure 1, whilst dozens form colonies.
In rare instances, a publisher has elected to have a zero moving wall, so their current issues are available. Males matured before females and had a shorter lifespan than the. The stegodyphus dufouri group contains four or five species depending on whether stegodyphus pacificus and stegodyphus dufouri are considered distinct including our exemplar, the social species stegodyphus sarasinorum. Lifehistory, bionomics and behaviour of the social spider.
Publication date 1911 topics paleography, greek, books history to 400 publisher leipzig. Understanding these mechanical responses require characterization of the rheological properties of silk beyond the simple forceextension relations which are widely reported. Behavioral responses vary with prey species in the social. Gajbe 2007 redescribed and reillustrated stegodyphus sarasinorum karsch including male. Social spider societies are characterized by cooperative prey capture, allomaternal care and shared nest building and web maintenance aviles, 1997, lubin and bilde, 2007. We tend to think of spiders as aggressive loners, who are happier to eat their siblings rather than live alongside them, but a few hundred of the 38,000 described spider species have truly gregarious lifestyles.
An estimate of age was gained from intraspecific sequence divergence. Sibling species, species groups, and parallel origin of social living. Stegodyphus was established by simon 1873, with the type species s. Comparative female genital morphology in stegodyphus spiders.
Xenopoecilus sarasinorum popta, 1905 report on itis. Sexual competition is shown to occur in the social spiderstegodyphus dumicola eresidae. Participation in prey capture was positively associated with. Strain softening and stiffening responses of spider silk. The degree of diversification of stegodyphus social spiders was inferred from a partial phylogeny of the genus and intraspecific divergence from geographical samples of the social species. The name is derived from ancient greek, meaning covered at least three species are social spiders, and several are known to use ballooning as a method of. Here we study the linear and nonlinear viscoelastic properties of dragline silk obtained from social spider stegodyphus sarasinorum using a microextension rheometer that we have developed. In social animals, group efficiency is often assumed to increase with task differentiation, but this requires that individuals are better than generalists at the task they specialize in. Stegodyphus is a genus of velvet spiders that was first described by eugene simon in 1873. Males of the stegodyphus dufouri group have a spiral conductor that lacks a free inner leaf and is shorter than the tegular. Gajbe 2007 4 rediscribed and reillustrated stegodyphus sarasinorum karsch including male. We used xray microcomputed tomography for 3d reconstruction of the anatomy of the female genital system in the social stegodyphus dumicola, s. Six stegodyphus sarasinorum attack an ant prey, while their more timid nestmates not shown remain in the safety of the nest. Effect of kleptoparasitic ants on the foraging behavior of.
Task specialization in two social spiders, stegodyphus. Engel department ofentomology, haworth hall, university ofkansas, lawrence, kansas 66045 usa. In rare instances, a publisher has elected to have a zero moving wall, so. The genus stegodyphus was divided into three groups africanus, dufouri and mirandus, based on differences in the genitalia of both sexes each containing one social and several subsocial species kraus and kraus, 1989. Unlike continuous extension data, our technique allows for the probing of the viscoelastic response by applying small perturbations about sequentially. The ants were found to be the most dominant among them. Here, we investigate the female genital morphology of seven eresid spider species.
Tikader 1963 illustrated pococks stegodyphus pacificus socialis for easy identification. Stegodyphus sarasinorum is an aridadapted social spider found in southcentral asia, including india, sri lanka, nepal and afghanistan. Stegodyphus simon 1873 and eresus walckenaer 1805 are two out of nine genera of the spider family eresidae c. Download pdf download all download jpeg 2000 download text. The moving wall represents the time period between the last issue available in jstor and the most recently published issue of a journal. The spider fauna of the entire regions of kavvayi river basin has never been documented or summarized. Twentynine colonies of a population of the cooperative spider stegodyphus sarasinorum karsch eresidae, from two sites in bangalore, karnataka state, india, were examined using protein allozyme electrophoresis.
The authors who will be invited to write chapters for this volume will be the very download preface 1 pdf 109 kb. Spider silk possesses unique mechanical properties like large extensibility, high tensile strength, supercontractility, etc. Twentytwo enzymes the products of 25 putative loci gave scorable results. The age and evolution of sociality in stegodyphus spiders.
Hundreds of greatest essays ever written get free ebooks. Tikader 1962 illustrated pococks stegodyphus pacificus, stegodyphus socialis for easy identification. Task specialization in two social spiders, stegodyphus sarasinorum eresidae and anelosimus eximius theridiidae. Population structure in an indian cooperative spider. International journal of science and research ijsr is published as a monthly journal with 12 issues per year. Araneae was undertaken in the jnana bharathi campus of bangalore university during summer 2010. Four species of spiders and two species of ants were observed as kleptoparasites and collected from the nest and webs of this social spider. Here we study the linear and nonlinear viscoelastic properties of dragline silk obtained from. Xenopoecilus sarasinorum popta, 1905 popta, 1905 etymology. This spider is a social spider that exhibits communal predation and feeding, where individuals live in large cooperatively built colonies with a nest or retreat constructed of silk woven using leaves, twigs, and food. Stegodyphus sarasinorum karsch is a sri lankan social spider that exhibits communal predation and feeding. A spiders feeding time is dependent on its position in the feeding sequence, with early feeders feeding longer than those arriving later. Based on a partial molecular phylogeny of the genus stegodyphus, we address the hypothesis that social spiders in this genus are evolutionary transient.
Cooperative foraging expands dietary niche but does not. Interestingly, we found that both species showed some degree of task specialization, but in distinctly different ways. We estimate the age of the three social species, test whether they represent an ancestral or derived state and assess diversification relative to subsocial congeners. Instegodyphus sarasinorum karsch the adult stage is attained after twelve instars. The biodiversity heritage library works collaboratively to make biodiversity literature openly available to the world as part of a global biodiversity community. Stegodyphus colonies contain up to a few hundred very highly related individuals. The various aspects of the bionomics and behaviour of this social spider, viz. Stegodyphus sarasinorum karsh eresidae is one of three permanently social species in its genus, and is found in india and some adjacent countries 26,27. Issn 23472677 suicidal maternal care in spider stegodyphus.
Pdf observation on a collection of tawny coster acraea. Volume 51, page 521 a note on the effect of light and the colour of the substratum on the settlement of barnacles. Stegodyphus mimosarum is commonly known as the african social velvet spider. Kleptoparasites of the social spider stegodyphus sarasinorum karsch 1891 were identified based on the observations done in the field.
Distribution of social spider stegodyphus sarasinorum along the altitudinal gradient of nilgiri biosphere reserve. In the social spider stegodyphus sarasinorum, we examined crosscontextual prey capture behavior of spiders with 2 prey species, namely, honeybees and grasshoppers over the long term 50 days commensurate to adult life spans. The secondary sexual characters become manifest in the twelfth instar. The present study covers the entire ecosystems of kavvayi river basin and. Notably, it is a referred, highly indexed, online international journal with high impact factor. A method for accurately estimating social spider numbers.792 901 1297 2 1147 380 760 1077 140 177 1059 369 17 34 81 674 1255 925 271 1513 1593 382 357 581 1512 573 813 975 837 1347 683 478 870 385 1267 429 473 899 43