Amblyomma dissimile Koch (Acari: Ixodidae) attacking Primolius maracana Vieillot (Psittaciformes: Psittacidae) in the Amazon region, State of Pará, Brazil

Distribution modeling of Amblyomma rotundatum and Amblyomma dissimile in Brazil: estimates of environmental suitability

The number of reports of tick parasitism in amphibians and reptiles has increased over the past few years, including new host and location records for Amblyomma rotundatum and Amblyomma dissimile. However, knowledge of the geographical distribution remains incomplete, and in many regions of Brazil, the presence of these vectors has not been investigated. Several candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity based on current climatic trends and future projected climate changes. Final models showed a good ability to discriminate A. rotundatum and A. dissimile current and future potential distributions. The entire country had higher predicted suitability for A. rotundatum while A. dissimile was mainly restricted to the Amazon and Pantanal biomes. A. rotundatum is a species with enormous potential for dissemination in the next decades, potentially through the legal and illegal transport of reptiles and amphibians. The proposed model is useful for targeting surveillance efforts increasing the efficiency and accuracy of future ecological research and tick management efforts.

Amblyomma ticks infesting amphibians and Squamata reptiles from the lower Amazon region, Brazil

Amphibians and Squamata reptiles belonging to a zoological collection were screened for ectoparasites, which were removed from the hosts and identified using morphological keys. Descriptive statistics and analysis of the association between the parasite and host characteristics (taxonomic group, capture location and habitat) were done. Among the 1256 animals examined (319 amphibians and 937 reptiles), 86 individuals were parasitized, corresponding to a frequency of 6.9% (6.6% reptiles and 7.5% amphibians). Ticks in the adult and nymph stages were identified to the species level; all of them belonged to the species Amblyomma dissimile. The larvae were identified to the genus level and were all Amblyomma sp. In total 69 larvae, 28 nymphs and eight adults were found. The most parasitized species was the frog Rhinella major: 24 parasitized animals of 65 examined (36.9%). There was a difference (P < 0.001) between parasitism by ticks of the genus Amblyomma with regard to the habitat of capture of the parasitized animal, with a higher parasitism rate in hosts that inhabited open areas as compared to animals ensconced in forest areas and edges of forests. New tick-host associations are given.

Wildlife species, Ixodid fauna and new host records for ticks in an Amazon forest area, Rondônia, Brazil

The objective of this work was to evaluate the diversity of ticks associated with free-living animals and to investigate new host records for ticks. Ticks were collected from animals rescued during the flood of the Jamari River in the municipality of Ariquemes, state of Rondônia, North Region of Brazil. A total of 39 animals were captured, out of which 10 were amphibians, 19 were reptiles and 10 were mammals. A total of 127 ticks of the Amblyomma genus were collected from these animals, distributed among seven species: Amblyomma dissimile, Amblyomma geayi, Amblyomma humerale , Amblyomma longirostre, Amblyomma nodosum , Amblyomma rotundatum and Amblyomma varium. In addition, one specimen of Rhipicephalus (Boophilus) microplus was collected. Among these specimens, 85 were adults and 42 were nymphs, with A. rotundatum being the most prevalent species. An Amblyomma spp. larvae was also collected from a lizard (Uranoscodon superciliosus), and one Amblyomma calcaratum and one Amblyomma dubitatum were recovered from the environment, thus totaling 130 ticks. Among the Ixodidae collected from different hosts, we provide the first report for the species A. rotundatum parasitizing Rhinella major, U. superciliosus, Leptophis ahaetulla, Chironius multiventris, and Mastigodryas boddaerti, as well as of A. humerale parasitizing U. superciliosus, A. geayi parasitizing Choloepus didactylus, and Rhipicephalus (B.) microplus parasitizing Alouatta puruensis.

Rickettsial infection in ticks (Acari: Ixodidae) from reptiles in the Colombian Caribbean

Although more reptiles are illegally traded in Colombia than any other group of animals, for both local and international markets, little is known about ticks associated with reptiles or pathogens associated with these ticks. In this study, ticks were collected from reptiles in Magdalena, Cesar and La Guajira regions in northern Colombia, and identified morphologically using taxonomic keys and molecularly by sequencing of the COI gene. In addition, Rickettsia spp. were detected by PCR amplifying the gltA, 16S rRNA, and sca1 genes. Ticks were identified as Amblyomma dissimile, representing the first record for this species in 17 of the 26 species of reptiles sampled. Additionally, our data expand the distribution range for this tick in Colombia. Rickettsia spp. DNA was detected in 18 ticks (3.6%) from 16 reptiles. Sequence analyses indicated that most of the Rickettsia were members of the R. monacensis clade, most closely related to Rickettsia sp. strain Colombianensi. We detected one tick infected with a Rickettsia with 99% identity to R. bellii.