Estratégias de forrageamento de Constrictotermes cyphergaster (Termitidae, Nasutitermitinae)

Abstract

The exploration of food resources is fundamental to the success of species in the environment and understand the strategies utilized to food catch implies in provide important data to the conservation of species and biological communities. Constrictotermes cyphergaster forages in open foraging trails and explores a lot of food resources, not knowing yet the reasons behind its varied diet. So, study the links between the consumption and characteristics of explored resources, as well as individuals organization at the foraging can auxiliate to understand the participation of this specie in the maintenance of arid environments that are distributed. The study was conducted in the Experimental Station of São João do Cariri, located in the São João do Cariri municipality, Paraíba, Brazil. Work was divided in two chapters, 1. The contents of N, P, K and Mg of resources were quantified from Cenostigma pyramidale e Aspidosperma piryfolium. The resources substrates were collected after the foraging monitoring of 10 nests, occurred in 15 days of october of 2018. The maximum and minimum distances of foraging trails were marked, besides the foraging time for the consumed resources, whether in live trees and/or disposed in the soil surface. The latter cited, disposed in different distances of the nests, were weighed to verify the the relation between the resources disponibility and the mean of distance traveled by termites during the foraging events. We verified significance for K in function of the resources height, as well as significative difference in the foraging time and trails distance. When utilized the weight of resources in each distances utilized, there was not significance in the trails extension. The significance of K can be explained by the relation existent in the accumulation of the mineral by the plant species as defense strategy against herbivores. Chapter aggregate informations about the food strategies of termites in semiarid regions, as well as highlights the need to preservation of the vegetation existent in environments inhabited by C. cyphergaster. In the chapter 2, four body measures were evaluated from 120 workers to verify dimorphism in the worker caste of C. cyphergaster. The proportion of each morphotype was estimated from 10.000 workers collected from 10 nests. Workers behavior during the foraging, number of interactions between them and crop volume of 200 of these individuals were analyzed. The analyzes implied in morphometric differences between the workers, corroborated by the principal components that resulted in two groups. There was significative variations in the individuals quantity of each morphotype, in the number of interactions during the foraging and in the crop volume. Results substantiate the affirmation that the workers of C. cyphergaster are dimorphic and have distinct functions during the foraging.