Social tolerance of spider Stegodyphus sarasinorum Karsch (1891) between their colonies under controlled and field conditions

Investigation on social interaction between the individuals of Stegodyphus sarasinorum of two different colonies and their cooperation in prey capture showed that members of different colony were socially accepted by both adults and juveniles. The study also revealed that this species prey upon rice ear bugs and cercopids which form major pests in paddy fields and banana plantation respectively.

Behavioral responses vary with prey species in the social spider, Stegodyphus sarasinorum

Predators living in social groups often show consistent interindividual differences in prey capture behavior that may be linked to personality. Though personality predisposes individuals for certain behaviors, responses can also be influenced by context. Studies examining personality-dependent participation in prey capture have largely employed only one prey species, offering the predator no choice. In nature, predators encounter a range of prey species, therefore participation in or leading a prey capture event must also depend on prey attributes (e.g., size and risk). 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. Here, we examined if an individual’s consistency to attack persisted within and between the 2 prey species (honeybees and grasshoppers) and if the same individuals attacked first with both prey species. Our results showed that interindividual differences in attacking persisted within and between the 2 prey species. Spiders showed greater participation in attacking grasshoppers relative to bees. Identities of the first attackers were not the same for bees and grasshoppers. Spiders showed greater consistency over time in attacking bees relative to grasshoppers. Bees attracted fewer attackers than size-matched grasshoppers. These results suggest that greater task specialization may be necessary to successfully subdue bees. Spiders handled bees more cautiously, which is likely to explain the observed plasticity in attacking the 2 prey species. Thus, participation in prey capture in social spiders is influenced by the attributes of prey species.

Stegodyphus semadohensis: A new species from family Eresidae, recorded from Satpuda, Maharashtra, India (Arachnida: Araneae: Eresidae)

Eresidae are represented poorly in Indian fauna. All over the world about hundred species in ten genera are known and about 29 species have been studied under the genus Stegodyphus. The genus Stegodyphus was established by Simon 1873, with the type species S. lineatus Latneille. Pocock (1900) described five species of Stegodyphus. Tikader (1963) illustrated Pococks Stegodyphus pacificus socialis for easy identification. Gajbe (2007) redescribed and reillustrated Stegodyphus sarasinorum Karsch including male. The study examines species in a relatively diverse lineage of genus Stegodyphus, where they undergone adaptive radiation. One new species of spider from family Eresidae, genus Stegodyphus (Stegodyphus semadohensis sp. nov. female) is recorded from Satpuda (Maharashtra State) India, during 2009.

Predatory behavior of a social spider, Stegodyphus sarasinorum (Araneae: Eresidae): why attack first?

Stegodyphus sarasinorum Karsch is a Sri Lankan social spider that exhibits communal predation and feeding. A spider's feeding time is dependent on its position in the feeding sequence, with early feeders feeding longer than those arriving later. Feeding time per spider does not decrease with increasing group size when compared with a given feeding position, temporally speaking. The first spider to feed is the only individual whose feeding time is not shortened by conspecifics.