Can't even trust the family? The web of the unusual web-building wolf spider Aglaoctenus lagotis (Araneae: Lycosidae) invaded by typical wandering wolf spiders

Arachnology ◽  
2021 ◽  
Vol 18 (7) ◽  
Author(s):  
Macarena González ◽  
Carlos A. Toscano-Gadea
Keyword(s):  
Wolf Spider ◽  
Wolf Spiders ◽  
The Family ◽  
Web Building ◽  
The Web

Life history of tundra-dwelling wolf spiders (Araneae: Lycosidae) from the Yukon Territory, Canada

2012 ◽  
Vol 90 (6) ◽  
pp. 714-721 ◽  
Author(s):  
J.J. Bowden ◽  
C.M. Buddle
Keyword(s):  
Reproductive Effort ◽  
Abiotic Factors ◽  
Wolf Spider ◽  
Local Variation ◽  
Yukon Territory ◽  
The Arctic ◽  
Wolf Spiders ◽  
Female Body Size ◽  
Trade Offs ◽  
History Of

We studied populations of three tundra-dwelling wolf spider (Lycosidae) species to determine reproductive trait relationships and developmental timing in the Arctic. We collected 451 Pardosa lapponica (Thorell, 1872), 176 Pardosa sodalis Holm, 1970, and 117 Pardosa moesta Banks, 1892 during summer 2008. We used log-likelihood ratio tests and multiple linear regressions to determine the best predictors of fecundity and relative reproductive effort. Female body size best explained the variation in fecundity and body condition was the best predictor for relative reproductive effort. We tested for a trade-off between the allocation of resources to individual eggs and the number of eggs produced (fecundity) within each species using linear regression. There was variation in detectable egg size and number trade-offs among sites and these may be related to local variation in resource allocation linked to density-related biotic or abiotic factors. These findings contribute to knowledge about the fitness of arctic wolf spiders in the region of study and are particularly relevant in light of the effects that climate changes are predicted to have on the arctic fauna.

Reproductive isolation and sex-role reversal in two sympatric sand-dwelling wolf spiders of the genus Allocosa

2008 ◽  
Vol 86 (7) ◽  
pp. 648-658 ◽  
Author(s):  
A. Aisenberg ◽  
F. G. Costa
Keyword(s):  
Reproductive Isolation ◽  
Sexual Size Dimorphism ◽  
Sex Role ◽  
Wolf Spider ◽  
Coastal Dunes ◽  
Pitfall Trap ◽  
Role Reversal ◽  
Adult Size ◽  
Wolf Spiders ◽  
Size Dimorphism

Allocosa brasiliensis (Petrunkevitch, 1910) is a nocturnal wolf spider inhabitant of coastal dunes. Pitfall-trap data suggested the occurrence of two sympatric and synchronic morphs, with differences in adult size and abdominal design (minor and major morphs). Previous studies performed with the major morph of A. brasiliensis, postulated courtship-role and sexual size dimorphism reversal for this spider. In the present study, we compare data on development and morphology and test reproductive isolation between morphs of A. brasiliensis, with the hypotheses that the two morphs are reproductively isolated and both show courtship-role reversal. As had been reported for the major morph of A. brasiliensis, the minor-morph females approached the burrows of minor-morph males, entered, initiated courtship, and after copulation, males closed their burrows with female cooperation from the inside. Females did not court or copulate with males belonging to the other morph and, in two cases, major-morph females cannibalised minor-morph males. Morphometrical and developmental data showed differences between morphs. The occurrence of copulation only between individuals of the same morph confirm reproductive isolation, supporting the occurrence of two species. Morphological and behavioural data are consistent with courtship-role-reversal hypotheses for the minor morph, constituting the second report in spiders of this atypical behaviour.

Effect of disturbance and distance from a riparian corridor on spiders in a temperate rainforest

2010 ◽  
Vol 40 (5) ◽  
pp. 904-916 ◽  
Author(s):  
Claudia R. Copley ◽  
Neville N. Winchester
Keyword(s):  
Coniferous Forest ◽  
Species Abundance ◽  
Riparian Ecosystems ◽  
Autocorrelation Analysis ◽  
Ancient Forest ◽  
The Family ◽  
Components Analysis ◽  
Riparian Corridor ◽  
Web Building ◽  
Malaise Traps

In anthropogenically disturbed forested riparian ecosystems that contain vagile organisms, we expect dispersal to be a factor that determines patterns of diversity that differ from similar, but continuous, undisturbed habitats. We studied the effects of habitat alteration on community composition by characterizing the spider assemblage of a riparian corridor in an ancient forest and a regenerating coniferous forest in the Carmanah Valley, Vancouver Island, British Columbia. Spiders were collected over a 15 month period using Malaise traps set along transects perpendicular to Carmanah Creek. We recorded 76 genera and 113 species representing 23 families. In both the regenerating coniferous forest and the ancient forest, a large proportion of the species were of the family Linyphiidae. Species abundance was similar in the two habitats but diversity was greater in the regenerating coniferous forest. The ancient forest was dominated by the web-building guild. Spatial autocorrelation analysis revealed no overall pattern in the species assemblages relative to the riparian corridor. Bray–Curtis similarity measure and principal components analysis results indicate that spider assemblages in the two habitats were significantly different in composition. These results suggest that habitat changes affect assemblages of spiders by altering dispersal, and these responses are evident a decade after disturbance.

Locomotion in Burrowing and Vagrant Wolf Spiders (Lycosidae)

1981 ◽  
Vol 92 (1) ◽  
pp. 305-321 ◽  
Author(s):  
T. M. WARD ◽  
W. F. HUMPHREYS
Keyword(s):  
Wolf Spider ◽  
The Body ◽  
Power Stroke ◽  
Phase Lag ◽  
Running Speed ◽  
Wolf Spiders ◽  
High Speeds ◽  
Phase Lags ◽  
The Relationship

Locomotion in the vagrant wolf spider Trochosa ruricola is compared to that in the burrow dwelling wolf spider Lycosa tarentula (Araneae: Lycosidae). L. tarentula takes relatively shorter steps than T. ruricola. At high speeds T. ruricola approximates an alternating tetrapod gait but this does not occur in L. tarentula. Phase lag differs between species and varies marginally with speed except for ipsilateral phase lags in L. tarentula which are erratic if they include leg 1. In both species the protraction/retraction ratio is directly related to both running speed and stepping frequency, but the relationship is more marked in L. tarentula. The protraction/retraction ratio is more variable in leg 1 and varies between legs along the body but by a greater amount in L. tarentula. In these spiders, in contrast to the situation in many insects, both the duration of protraction and retraction show marked inverse relationships to stepping frequency. The power stroke (retraction) occupies a variable proportion of the stepping cycle, which is not the case in other spiders, and this proportion is lower than for other spiders. It is suggested that the first pair of legs is used more for sensory than for locomotory purpose and that this is more marked in the burrow dwelling species, L. tarentula.

Upcoming SIGWEB supported conferences

2021 ◽  
pp. 1-4
Author(s):  
Daniel Roßner
Keyword(s):  
Interest Group ◽  
Special Interest ◽  
Special Interest Group ◽  
Wide Range ◽  
The Family ◽  
Fourth Decade ◽  
Web Community ◽  
Short Courses ◽  
Remote Participation ◽  
The Web

The Special Interest Group on Hypertext and the Web, SIGWEB was created in 1989 to support the community participating in the annual ACM Hypertext Conference. In its fourth decade, SIGWEB continues its efforts to support a wide range of communities and conferences. Recently, the Web Conference's legal and financial sponsorship was transferred to SIGWEB and thus joins the family of seven annual conferences in 2022. SIGWEB supports several specialized conferences, short courses, and workshops of different sizes, as well as the annual Hypertext Conference. SIGWEB sponsored conferences focus on timely topics in applied and computational hypertext and Web disciplines and provide a place for members and the entire applied Hypermedia and Web community to exchange ideas and to meet with and expand their network of colleagues. In this article, we provide a brief overview of SIGWEB sponsored conferences, in addition to events that are in cooperation with SIGWEB. Due to the current Corona crisis, many event organizers opted for an online conference format or allow remote participation. These conferences are marked accordingly.

scholarly journals Spiders in space—orb-web-related behaviour in zero gravity

2020 ◽  
Vol 108 (1) ◽  
Author(s):  
Samuel Zschokke ◽  
Stefanie Countryman ◽  
Paula E. Cushing
Keyword(s):  
International Space Station ◽  
Space Station ◽  
Zero Gravity ◽  
Random Orientation ◽  
Natural Conditions ◽  
International Space ◽  
Orb Web ◽  
Web Building ◽  
The Web

AbstractGravity is very important for many organisms, including web-building spiders. Probably the best approach to study the relevance of gravity on organisms is to bring them to the International Space Station. Here, we describe the results of such an experiment where two juvenile Trichonephila clavipes (L.) (Araneae, Nephilidae) spiders were observed over a 2-month period in zero gravity and two control spiders under otherwise identical conditions on Earth. During that time, the spiders and their webs were photographed every 5 min. Under natural conditions, Trichonephila spiders build asymmetric webs with the hub near the upper edge of the web, and they always orient themselves downwards when sitting on the hub whilst waiting for prey. As these asymmetries are considered to be linked to gravity, we expected the spiders experiencing no gravity to build symmetric webs and to show a random orientation when sitting on the hub. We found that most, but not all, webs built in zero gravity were indeed quite symmetric. Closer analysis revealed that webs built when the lights were on were more asymmetric (with the hub near the lights) than webs built when the lights were off. In addition, spiders showed a random orientation when the lights were off but faced away from the lights when they were on. We conclude that in the absence of gravity, the direction of light can serve as an orientation guide for spiders during web building and when waiting for prey on the hub.

scholarly journals Spiders by Night: An Outdoor Investigation Integrating Next Generation Science Standards

2019 ◽  
Vol 81 (8) ◽  
pp. 561-567
Author(s):  
Kathryn S. Craven ◽  
Alex Collier ◽  
Jay Y. S. Hodgson
Keyword(s):  
Wolf Spider ◽  
Field Investigation ◽  
Next Generation Science Standards ◽  
Laboratory Instruction ◽  
Next Generation ◽  
Science Standards ◽  
Natural Habitats ◽  
Wolf Spiders ◽  
Field Investigations ◽  
History Of

Field investigations represent an excellent opportunity to integrate the Next Generation Science Standards to complement and enhance both classroom and laboratory instruction. This inquiry-based exercise is designed to introduce students to the basic anatomy, ecology, and natural history of a common backyard denizen, the wolf spider (Lycosidae). Students are charged with developing one or more testable hypotheses regarding wolf spiders in their own backyards. Wolf spiders are an ideal subject for field investigation because their secondary eyes possess a highly reflective layer called the tapetum lucidum. At night, this layer produces an unmistakable “eyeshine” when viewed with the beam of a flashlight. Playing the role of students, we tested the hypothesis that wolf spiders should occur at higher density in an undeveloped field than in a typical backyard. To test this, we utilized random quadrat sampling in both habitats using flashlights to detect nocturnal eyeshine. Students obtaining similar results would likely have concluded that wolf spiders were more abundant in natural habitats.

scholarly journals Proteotranscriptomic Insights into the Venom Composition of the Wolf Spider Lycosa tarantula

Toxins ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 501
Author(s):  
Dominique Koua ◽  
Rosanna Mary ◽  
Anicet Ebou ◽  
Celia Barrachina ◽  
Khadija El Koulali ◽  
...  
Keyword(s):  
Prey Capture ◽  
Wolf Spider ◽  
Secretory Proteins ◽  
Crude Venom ◽  
Wolf Spiders ◽  
Original Source ◽  
Venom Composition ◽  
Venom Glands ◽  
Ambush Predators ◽  
Venom Proteins

Spider venoms represent an original source of novel compounds with therapeutic and agrochemical potential. Whereas most of the research efforts have focused on large mygalomorph spiders, araneomorph spiders are equally promising but require more sensitive and sophisticated approaches given their limited size and reduced venom yield. Belonging to the latter group, the genus Lycosa (“wolf spiders”) contains many species widely distributed throughout the world. These spiders are ambush predators that do not build webs but instead rely strongly on their venom for prey capture. Lycosa tarantula is one of the largest species of wolf spider, but its venom composition is unknown. Using a combination of RNA sequencing of the venom glands and venom proteomics, we provide the first overview of the peptides and proteins produced by this iconic Mediterranean spider. Beside the typical small disulfide rich neurotoxins, several families of proteins were also identified, including cysteine-rich secretory proteins (CRISP) and Hyaluronidases. Proteomic analysis of the electrically stimulated venom validated 30 of these transcriptomic sequences, including nine putative neurotoxins and eight venom proteins. Interestingly, LC-MS venom profiles of manual versus electric stimulation, as well as female versus male, showed some marked differences in mass distribution. Finally, we also present some preliminary data on the biological activity of L. tarantula crude venom.

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