Myrmecophily and Myrmecophagy of Attacobius lavape (Araneae: Corinnidae) on Solenopsis saevissima (Hymenoptera: Myrmicinae)

Abstract

Attacobius lavape, a small spider from the Corinnidae family, has been recently described living inside a fire ant colony of Solenopsis saevissima species in the municipality of Morrinhos, south region of the Goiás State, Brazil. Yet several aspects of this spider relationship with the host ant remain unknown. In this way, we performed an extension study to determine its local (Morrinhos) and regional (latitudinal transect) occurrence. We also investigated if the spider uses the host ant as a feeding source. For this, we established arenas with a known number of young and adult ant individuals plus one spider and observed the feeding rate for some determined time. Regarding local distribution, differently from most socially parasitic myrmecophiles, A. lavape showed high local infestation, being found in 47% of the colonies in the sites where the spider occurred, and high transmission, being found in 42% of the 12 collection sites. Regionally, among the 11 study sites, this species only occurred in the municipality of Morrinhos, but its distribution still needs to be verified in the north region. Attacobius lavape consumed eggs, larvae and pupae, confirming that the myrmecophily was explained by myrmecophagy. The spiders consumed eggs (not estimated), 4.45 ± 2.14 larvae and/or 3 ± 0.87 pupae per day. Considering that the mean abundance was approximately seven spiders per colony (extent 1-23), we foresee an impact of 35 larvae and/or 21 pupae consumed per day in each hosting colony. The possibility of consuming sexual eggs, larvae and pupae classifies A. lavape as a potential agent of biological control of S. saevissima.

Keywords

• fire ant
• inquiline
• social parasite
• biological control