Hosts, distribution and genetic divergence (16S rDNA) of Amblyomma dubitatum (Acari: Ixodidae)

Abstract

We supply information about hosts and distribution of Amblyomma dubitatum. In addition, we carry out an analysis of genetic divergence among specimens of A. dubitatum from different localities and with respect to other Neotropical Amblyomma species, using sequences of 16S rDNA gene. Although specimens of A. dubitatum were collected on several mammal species as cattle horse, Tapirus terrestris, Mazama gouazoubira, Tayassu pecari, Sus scrofa, Cerdocyon thous, Myocastor coypus, Allouata caraya, Glossophaga soricina and man, most records of immature and adult stages of A. dubitatum were made on Hydrochoerus hydrochaeris, making this rodent the principal host for all parasitic stages of this ticks. Cricetidae rodents (Lundomys molitor, Scapteromys tumidus), opossums (Didelphis albiventris) and vizcacha (Lagostomus maximus) also were recorded as hosts for immature stages. All findings of A. dubitatum correspond to localities of Argentina, Brazil, Paraguay and Uruguay, and they were concentrated in the Biogeographical provinces of Pampa, Chaco, Cerrado, Brazilian Atlantic Forest, Parana Forest and Araucaria angustifolia Forest. The distribution of A. dubitatum is narrower than that of its principal host, therefore environmental variables rather than hosts determine the distributional ranges of this tick. The intraspecific genetic divergence among 16S rDNA sequences of A. dubitatum ticks collected in different localities from Argentina, Brazil and Uruguay was in all cases lower than 0.8%, whereas the differences with the remaining Amblyomma species included in the analysis were always bigger than 6.8%. Thus, the taxonomic status of A. dubitatum along its distribution appears to be certain at the specific level.

Morphological and molecular identification of ticks infesting Boa constrictor (Squamata, Boidae) in Manaus (Central Brazilian Amazon)

“…Variations in DNA sequences encoding 16S rRNA among individuals of the same species are also common (NAVA et al, 2010), which explains the polymorphism of this marker found in the present study in comparison to the corresponding A. rotundatum sequence available in GenBank under accession number EU805569. The analysis of this marker confirmed the identification of A. rotundatum and A. dissimile and detected new sequences in these organisms that are not found in the public database, which greatly improved our confidence in the identity of the individuals, based on morphological criteria.…”

“…The DNA sequences of this marker among species of Amblyomma are reported to have 6.4 to 20.4% identity rates. Labruna et al (2009) and Nava et al (2010) studied 24 sequences of 16S rRNA from Amblyomma and found identity ranging from 10 to 18%. The data presented herein broaden the variation range of this marker in Amblyomma species, as 28 sequences were analyzed (Table 2).…”

Ticks (Acari: Ixodidae) associated with small terrestrial mammals in the state of Minas Gerais, southeastern Brazil

“…(Nava et al 2010b). Here, we report this tick on Lutreolina crassicaudata (Desmarest) for the first time.…”

“…L. crassicaudata is a nocturnal and semi-aquatic marsupial that uses burrows close to water courses for shelter (Santori et al 2005). Thus, its ecological niche is similar to that of capybaras (H. hydrochaeris), the main host of A. dubitatum (Nava et al 2010b). We report nymphs of A. ovale on the rodents Thrichomys apereoides (Lund) and Trinomys setosus (Desmarest) for the first time.…”

Femoral artery in a Crab-eating fox: case report

“…Although this species have been getting attention in Parasitology recently (CATENACCI, GRISE, DA SILVA et al, 2010;LUX HOPPE, ARAÚJO DE LIMA, TEBALDI et al, 2010;NAVA, VENZAL, LABRUNA, et al 2010;SOUZA, ALMEIDA ADO, FREITAS et al 2010), we could find information in other fields of study such as anatomy (BARISSON, LOURO, DIAS et al, 2012). Classic titles, describe the anatomy of arterial system of the domestic animals in details (EVANS and CHRISTENSEN, 1979;GETTY, 1986;KÖNIG and LIEBICH, 2011) but not in wild carnivores.…”