Ixodes schulzei Aragão & Fonseca is an endemic tick to Brazil and has already been reported in the northern (State of Rondonia), southeastern (States of Minas Gerais, Rio de Janeiro and Sao Paulo) and southern (State of Santa Catarina) regions, always found in association with the water rat Nectomys squamipes (Brandt). This communication records the first occurrence of this tick species in the State of Parana, southern region of Brazil, and it constitutes its first report on Akodon montensis (Thomas) Aragão and Fonseca, 1951 (ONOFRIO et al., 2009;DANTAS-TORRES et al., 2009). A ninth species named Ixodes serrafreirei Amorim, Gazeta, Bossi and Linhares, 2003 was proposed based on the nymphal stage (AMORIM et al., 2003), but due to lack of proper description I. serrafreirei has been regarded as a nomen nudum (VENZAL et al., 2008;GUGLIELMONE et al., 2009).All Ixodes species are restricted to wild hosts, primarily mammals, but two are exclusively found in birds (LABRUNA et al., 2003;ONOFRIO et al., 2006). Among these species, three are only known from females: I. amarali, I. fuscipes and I. schulzei (BARROS-BATTESTI et al., 2007). The latest species is endemic to Brazil and it has been found always in association with the water rat Nectomys squamipes (Brandt). Previous studies of life cycle under laboratory conditions suggest that I. schulzei could be a parthenogenetic species, since only female ticks were obtained from engorged nymphs (LABRUNA et al., 2003). Barros-Battesti et al. (2007) described the immature stages and redescribed the female of I. schulzei. This species has been reported from the states of Minas Gerais, Rio de Janeiro, Sao Paulo (southeastern), Santa Catarina (southern) and Rondonia (northern) (LABRUNA et al., 2003;ARZUA et al., 2005). This communication records the first occurrence of this tick species in State of Parana, southern region of Brazil, and it constitutes its Rev. Bras. Parasitol. Vet., Jaboticabal, v. 22, n. 1, p. 159-161, jan.-mar. 2013 Onofrio, V.C. et al. (Figure 1). The rodent A. montensis was the most frequently trapped species followed by O. russatus and N. squamipes. On this latest rodent, 52 immature ticks of the species I. schulzei were collected. Two nymphs of this tick species were also found on O. russatus; they were preserved in alcohol and deposited at the Acari Collection from "Instituto Butantan" under the number IBSP 09130. In June 2009, we returned to the same area to make new collects of rodents. During 5 days, a total of 14 specimens of Akodon were trapped, but no N. squamipes was collected. Unexpectedly, two larvae and one nymph of I. schulzei were collected on A. montensis. The identification of the latter host was based on cytogenetic data (2n = 24 e 2n = 24 + 1B) according to Christoff (2007).The nymph died after collection and it was then immersed in alcohol. Larvae were taken to the laboratory, fed on Calomys callosus Rengger, and maintained in BOD incubator at 27 °C and 95% RH; the same was done with the two emerged nymphs. On September 14, ...