Abstract
Amblyomma varium Koch, 1844 is a Neotropical tick, known as the ‘sloth’s giant tick’, with records from southern Central America to Argentina. It is found almost exclusively on mammals of the families Bradypodidae and Magalonychidae (Xenarthra). Differences exist in discussions with regard to the dentition of the female hypostome being either 3/3 or 4/4. The male was also originally described as having a short spur on coxa IV, but some specimens recently collected from different Brazilian localities have this spur three times longer. These differences beg the question of whether there is more than one species included under this taxon. In order to answer this question and to clarify the taxonomic characters of this species, 258 adult specimens were examined, and a redescription of male and female based on light and scanning electron microscopy is provided. In addition, DNA was extracted from males with either a long or a short spur on coxa IV to help settle this question for future investigations on their taxonomy. The morphological study showed that the dental formula pattern for males and females is 3/3 and 4/4, respectively. When sequenced, the 12 S rDNA genes of both A. varium males with long and short spurs on coxa IV were found to be identical, indicating that the length of the spurs on coxa IV is likely to be an intraspecifically polymorphic character of this species.
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References
Aragão, H. B. (1936). Ixodidas brasileiros e de alguns países limitrophes. Memórias do Instituto Owaldo Cruz, 31, 759–844.
Aragão, H. B., & Fonseca, F. (1961). Notas de Ixodologia. VII. Lista e chave para os representantes da fauna ixodológica brasileira. Memórias do Instituto Oswaldo Cruz, 59, 115–149.
Beati, L., & Keirans, J. E. (2001). Analysis of the systematic relationships among ticks of the genera Rhipicephalus and Boophilus (Acari: Ixodidae) based on mitochondrial 12 s ribosomal DNA gene sequences and morphological characters. Journal of Parasitology, 87, 32–48.
Boero, J. J. (1957). Las Garrapatas dela República Argentina (Acarina-Ixodoidea) (113 pp). Buenos Aires: Univ. de Buenos Aires.
Cimardi, A. V. (1996). Mamíferos de Santa Catarina (302 pp). Florianópolis: FATMA.
Cooley, R. A., & Kolhs, G. M. (1942). Antricola new genus, Amblyomma gerschi new species, and notes on Ixodes spinipalpis (Acarina: Ixodoidea). Public Health Reports, 57, 1733–1736.
Fairchild, G. B., Kohls, G. M., & Tipton, V. J. (1966). The ticks of Panama (Acarina: Ixodoidea). In: R. L. Wenzel, & V. J. Tipton (Eds.), Ectoparasites of Panama (pp. 167–219). Chicago: Field Museum of Natural History.
Guglielmone, A. A., Estrada-Peña, A., Keirans, J. E., & Robbins, R. G. (2003). Ticks (Acari: Ixodida) of the Neotropical Zoogeographic Region (173 pp). Houten: Atalanta, International Consortium on Tick and Tick-borne Diseases (ICTTD-2).
Guglielmone, A. A., & Nava, S. (2007). Las garrapatas argentinas del género Amblyomma (Acari: Ixodidae): distribución y hospedadores. Revista de Investigación Agropecuaria, in press.
Guimarães, J. H., Tucci, E. D., & Barros-Battesti, D. M. (2001). Ectoparasitos de importância veterinária (218 pp). São Paulo: Plêiade/Fapesp.
Jones, E. K., Clifford, C. M., Keirans, J. E., & Kohls, G. M. (1972). The ticks of Venezuela (Acarina: Ixodoidea) with a key to the species of Amblyomma in the western hemisphere. Brigham Young University Science Bulletin, Biological Series, 17, 1–40.
Koch, C. L. (1844). Systematische übersicht über die Ordnung der Zecken. Archiv für Naturgeschichte, 10, 217–239.
Labruna, M. B., Camargo, L. M. A., Terrassini, F. A., Ferreira, F., Schumaker, T. T. S., & Camargo, E. P. (2005). Ticks (Acari: Ixodidae) from the state of Rondônia, western Amazon, Brazil. Systematic & Applied Acarology, 10, 17–32.
Maddison, D. R., & Maddison, W. P. (2000). MacClade 4: Analysis of phylogeny and character evolution. Sunderland, MA: Sinauer Associates, (CD-ROM).
Marques, S. M., Barros-Battesti, D. M., Faccini, J. L., & Onofrio, V. C. (2002). Brazilian distribution of Amblyomma varium Koch, 1844 (Acari: Ixodidae), a common parasite of sloths (Mammalia: Xenarthra). Memórias do Instituto Oswaldo Cruz, 97, 1141–1146.
Need, J. T., Dale, W. E., Keirans, J. E., & Dasch, G. A. (1991). Annotated list of ticks (Acari: Ixodidae, Argasidae) reported in Peru: distribution, hosts, and bibliography. Journal of Medical Entomology, 28, 590–597.
Neumann, G. (1899). Révision de la famille des ixodidés. Mémoires de la Société Zoologique de France, 12, 107–294.
Neumann, G. (1901). Révision de la famille des ixodidés. Mémoires de la Société Zoologique de France, 14, 249–372.
Robinson, L. E. (1926). Ticks. A monograph of the Ixodoidea. Part IV. The genus Amblyomma (302 pp). London: Cambridge University Press.
Sinkoc, A. L., Brum, J. G. W., Begrow, A., & Picanço, M. (1997). Ocorrência de Amblyomma varium Koch, 1884 em preguiça (Bradypus variegatus) no Estado de Pernambuco, Brasil. Arquivos da Faculdade de Medicina Veterinária UFRGS, 25, 105–107.
Swofford, D. L. (2000). PAUP* phylogenetic analysis using parsimony (*and other methods). Version 4.0. Sunderland, MA: Sinauer Associates.
Acknowledgements
We are grateful to the curator, Jason A. Dunlop, from Naturhistorisches Forschungsinstitut, Museum für Naturkunde Zentralinstitut der Humboldt-Universität zu Berlin, for permitting us to revise the type-specimens of A. varium and A. varium albida. This study was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (Project Biota-Fapesp no. 99/05446–8) and, in part, by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq 478950/2004–7) to DMBB and to MBL (CNPq research fellowship).
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Onofrio, V.C., Barros-Battesti, D.M., Marques, S. et al. Redescription of Amblyomma varium Koch, 1844 (Acari: Ixodidae) based on light and scanning electron microscopy. Syst Parasitol 69, 137–144 (2008). https://doi.org/10.1007/s11230-007-9128-0
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DOI: https://doi.org/10.1007/s11230-007-9128-0