Evidence of subsocial behavior through analysis of prey capture and feeding in a new species of Anelosimus (Araneae : Theridiidae)

Sociality is a little studied, little occurring, and unique trait in spider biology. Recently, in the genus Anelosimus, where sociality has originated eight or nine times, research has shown that more quasisocial species exist at low elevations and almost all subsocial species at higher elevations. The purpose of this study was to determine the sociality of a new species of Anelosimus, and add to the knowledge base of social Anelosimus spiders. Analysis of prey capture and feeding has provided evidence for a subsocial classification. In 12 webs of a female and her offspring, juveniles coordinated efforts to capture prey. Almost all of the spiders in the web fed communally (R=0.97; p=.0001). Juveniles more adeptly captured prey smaller than their body size prey, and spent longer capturing prey larger than their body. Other natural history aspects of these spiders were described, including guarding of egg sacks, web heights of 0.2m-2.3m, and tendency of webs to be found on tips of branches. With as much knowledge as to the extent of sociality in Anelosimus, we may be able to accurately analyze trends, and provide insight into the mechanisms of evolution and their origins. El comportamiento social en las arañas es poco frecuente y estudiado, así mismo parece estar ligado a un único rasgo en la biología de las arañas. Recientemente, en el genero Anelosimus donde el comportamiento social se ha originado ocho o nueve veces, las investigaciones han demostrado que mas especies cuasi sociales se encuentran a elevaciones bajas y casi todas las especies subsociales a mayores elevaciones. El propósito de este estudio fue determinar el grado de sociabilidad en una nueva especie de Anelosimus y añadir mas conocimiento a la base de sociabilidad en este genero de araña.https://digitalcommons.usf.edu/tropical_ecology/1300/thumbnail.jp