COMPONENT COMMUNITY OF ECTOPARASITES ASSOCIATED WITH Abrothrix olivaceus WATERHOUSE (CRICETIDAE: SIGMODONTINAE: ABROTRICHINI) IN PATAGONIA, ARGENTINA

SANCHEZ, JULIANA P.; UDRIZAR SAUTHIER, DANIEL E.; LARESCHI, MARCELA

Mendoza

Congreso; X International Congress of Mammalogy IMC10; 2009

SAREM-IMF

RESUMEN: In Argentina, Abrothrix olivaceus is distributed from Mendoza to Tierra del Fuego. Fleas, lelapid mites and ticks were mentioned associated with this rodent, but no studies considering different higher taxa together were performed. In this contribution we study component community of ectoparasites of A. olivaceus in two extreme sectors of its eastern distribution. Rodents were captured in Chubut (Pico Salamanca 45º24’32’’S; 67º24’58’’W), and Santa Cruz (Puerto Santa Cruz 51º56’09”S; 69º34’26”W, and Pali Aike 50º06’30”S; 68º27’37”W; data were pooled). Ectoparasites were collected by brushing the furs of the hosts, fixed in 96% ethanol and mounted following conventional techniques. Ectoparasites were identified at higher taxa level. Frequency (F), mean abundance (MA) and Prevalence (P) for every taxa were calculated. In Chubut, A. olivaceus represented 32% of the trapped rodents (N=44); ectoparasites total: [MA=1.45; P=48%]; fleas (Insecta, Siphonaptera): [N=27; F=60%; MA=0.87; P=35%]; mites (Acari, Macronyssidae): [N=13; F=29%; MA=0.38; P=10%]; ticks (Acari: Ixodidae): [N=5; F=11%; MA=0.09; P=9%]. In Santa Cruz, A. olivaceus represented 95% (N=32); ectoparasites total: [MA=5.40; P=93%]; fleas: [N=139; F=58.5%; MA=3.13; P=77%]; mites: [N=72; F=30%; MA=1.54; P=50%]; ticks [N=28; F=11,5% MA=0.63; P=36%]. No lelapid mites were collected, while macronyssid mites are reported for the first time on A. olivaceus, and in Patagonia. Frequency of every higher taxa was similar in both areas, supporting that the structure of the component community was constant across latitudinal gradients. High P and MA in Santa Cruz are related with the dominance of A. olivaceus. High abundance of a host population, decreases its health status, as well as increases the frequency of contacts among rodents, which in both cases give ectoparasites better opportunities to colonize new hosts, and to increase their populations. Further studies including more localities, will allow to know if the structure of ectoparasite component community is constant along the geographical range of A. olivaceus.