The taxonomic diversity of the helminths comunity of two Akodon congeners species in Argentina

NAVONE, GRACIELA T.; ROBLES, MARÍA DEL ROSARIO; GALLIARI, CARLOS; NOTARNICOLA , JULIANA

Mendoza

Congreso; XX internacional Mammalogical Congress; 2009

Akodon azarae and A. montensis are sigmodontine rodents distributed largely in the Argentine. In most of their range, these species are allopatric, since they are adapted to different environments. The richness of helminthes of A. azarae is quite well-known. However, few studies were carried out on the parasitefauna of A. montensis to date. The aim of this study is to compare the rischness of helminthes present in this congeners host species from Argentina, determining if the presence of each taxa could correspond to phylogenetic or ecological process. In Argentina, a total of 98 species of A. azarae and 177 species of A. montensis representatives of a complete range of their geographical distribution were examined. The richness of taxa was similar in both host species (A. azarae =13 y A. montensis =9). The Jaccard coefficient showed very low specific similarity between the two component communities (0.1). However, it should be considered that the same taxa of parasites (families or genus) are represented in both species. The curves of accumulation of species are very near of reaching the asymptote showing that the helminthes found represent almost the total of maximum number of parasite species that can explode each species of rodents. However, the nature of the curve in A. azarae indicates that fewer hosts are necessary to obtain a similar result to A. montensis. It is few probable that future studies enlarge significantly the diversity found here. Therefore, the results of this study will allow predicting the habitual parasite fauna of these two host species from Argentina. The divergence of two parts of an ancestral host for an environmental barrier could interrupt the gene flow between each component communities causing event of co-speciation. In this study, the presence of species congeners shared in the two host congeners could indicate the possible presence of this event.