Red Ant Species Research Articles

Capturing insects in guava orchard with soil trap

The development of equipment for capturing insects, in order to meet the need of technicians and researchers, is of paramount importance to obtain accurate data on the population of insects in a given area. The soil trap is used in order to have a sample of the population size of the macro fauna present in the soil. The objective of the experiment was to capture insects of different orders with soil traps and to verify the constancy of the orders of insects in the Experimental Area of Guava Orchards of Federal Institute of Education, Science and Technology of Paraiba Campus Sousa, Unit II in São Gonçalo, Paraiba State. For this, six soil traps were installed, arranged in strategic points, with 30 m spacing between them, in a triangle shape. The traps were made of 2-liter plastic bottles (PET) of soft drink, cut in half and 10 cm in diameter and 15 cm high. Inside each bottle 300 mL of water and two tablespoons of neutral detergent were placed to break the surface tension of the water. The main orders of insects were respectively, Hymenoptera with 100% of the total species collected in the soil traps; Neuroptera 66.66%, Orthoptera 33.33% and Diptera with 33.33%. In the experiment, a constant frequency was observed, that is, those present in more than 50% of the collections, in particular the order Hymenoptera, with the red ant species (Formica rufa), followed by lion ant (Myrmeleon brasiliensis).

Gene flow and population viscosity in Myrmica ants

The amount of gene flow and population viscosity were studied in two red ant species, Myrmica ruginodis and M. rubra. Differentiation between populations at the local scale (within the dispersal distance of individuals) and between localities further apart was estimated using Wright's F-statistics. Population viscosity was described using spatial autocorrelation of allele frequencies of nests. The differentiation patterns in the two species are clearly distinct, FST values being an order of magnitude larger in M. rubra (M. rubra: FST = 0.205 between sites within localities and 0.199 between localities; M. ruginodis: FST = 0.027 and 0.014 between sites within localities, 0.009 between localities). Thus, assuming the island model, much less gene flow occurs between neighbouring M. rubra than M. ruginodis sites. Allele frequencies of nests close to each other are positively autocorrelated in both species. This suggests that new nests are commonly founded close to the mother nest, most probably by division of existing nests. M. rubra forms large multinest societies, which dominate substantial areas, whereas such multinest colonies are rare in M. ruginodis.

Queen Number as an Adaptable Trait: Evidence from Wild Populations of Two Red Ant Species (Genus myrmica)

D'apres Nonacs les hypotheses expliquant la polygynie peuvent etre classees dans quatre groupes ne s'excluant pas: la selection kin, le mutualisme, la selection de groupe, et une forme de parasitisme.Cet auteur a developpe des modeles pour tester si la premiere hypothese peut expliquer l'evolution de la polygynie.Cette etude recherche les variations intraspecifiques des niveaux de polygynie et les correlations ecologiques qui peuvent decouler des conclusions de Nonacs, en presentant et en analysant les donnees d'une etude longitudinale sur les nombres de reines dans les populations de M. rubra et M. limanica.