Topic
Gasteracantha
About: Gasteracantha is a research topic. Over the lifetime, 17 publications have been published within this topic receiving 244 citations.
Papers
TL;DR: A phylogenetic tree based on partial sequences of COI, 16S, and H3 genes recovered Gasteracanthinae as a monophyletic group and supported the existence of three clades as mentioned in this paper.
Abstract: Spiny-backed orb-weaving spiders of the subfamily Gasteracanthinae are broadly distributed in the Old World. Despite their use as a model species in biology, evolution, and behavior because of their extraordinary characteristics, the systematics of this group of spiders are still poorly understood. This study elucidates the systematics of Gasteracanthinae in Thailand based on morphological and molecular-based analyses. In total, seven species from three genera, namely Gasteracantha, Macracantha, and Thelacantha, were recorded in Thailand. Shape of abdominal spines, pattern of sigilla, and female genitalia are significant characters for species identification. In contrast, coloration shows highly intraspecific variation in most species within Gasteracanthinae. A phylogenetic tree based on partial sequences of COI, 16S, and H3 genes recovered Gasteracanthinae as a monophyletic group and supports the existence of three clades. Gasteracantha hasselti is placed as a sister taxon to Macracantha arcuata. Hence, we propose to transfer G. hasselti to Macracantha. Moreover, molecular species delimitation analyses (ABGD, bPTP, and GMYC) using 675 bp of COI gene support all nominal species, with evidence of possible additional cryptic species.
65 citations
TL;DR: In general, wasps avoid provisioning the early larval instar with species of Gasteracantha, perhaps because the newly emerged wasp larvae cannot penetrate the hard integuments of these spiders.
Abstract: The mud dauber wasp Sceliphron laetum (F. Smith) lays a single egg in a mud chamber that is provisioned almost exclusively with orb-weaving spiders. In Madang, Papua New Guinea, the wasps provision their chambers with between three and nine spiders that weigh between 0.01 and 0.28 g and are from at least twelve species. The number of spiders placed in each chamber is negatively correlated with the mean mass of each spider. A field experiment revealed that females cease provisioning after capturing a certain mass of spiders, rather than simply filling each chamber to its volumetric capacity. Furthermore, the wasps select different spider species according to the provisioning sequence. In general, wasps avoid provisioning the early larval instar with species of Gasteracantha, perhaps because the newly emerged wasp larvae cannot penetrate the hard integuments of these spiders.
42 citations
TL;DR: Experiments with dead Nephila clavipes show that postures described as thermoregulatory do, in fact, reduce absolute temperatures compared to normal predatory postures, and can provide insights into the probable habitat distributions of species whose coloration is known but whose ecology is presently unknown.
37 citations
TL;DR: A novel way in which spiders can increase their foraging efficiency by decreasing silk investment is demonstrated, whereby a spider spinning a web within an existing aggregation can attach the support threads of its web to those of other webs, thereby exploiting the silk produced by other spiders.
Abstract: The potential costs and benefits of foraging in aggregations are examined for the orb-spinning spider Gasteracantha minax. Web-site tenacity is low in this species; individuals frequently move among sites, thereby joining aggregations of different sizes. Female spiders in aggregations suffered lower predation rates and attracted more males than their solitary counterparts. However, aggregated eggsacs, probably produced by females in aggregations, experienced higher rates of parasitism than solitary eggsacs. We found no evidence of higher prey capture success rates among spiders in aggregations. However, we demonstrate a novel way in which spiders can increase their foraging efficiency by decreasing silk investment. A spider spinning a web within an existing aggregation can attach the support threads of its web to those of other webs, thereby exploiting the silk produced by other spiders.
28 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 2 |
| 2017 | 2 |
| 2015 | 1 |
| 2014 | 1 |
| 2009 | 1 |