title: Different lines of evidence used to delimit species in ticks: A study of the South American populations of Amblyomma parvum (Acari: Ixodidae).
abstract: The goal of this work was to combine different lines of evidence besides that of molecular markers to delimit species in ticks when the molecular data are not totally congruent. Two groups (Argentina, Brazil) of South American populations of Amblyomma parvum were compared to test whether the splitting of these two lineages suggested by genetic analyses is complete. Comparative studies of reproductive compatibility, morphological analyses of fixed characters, and comparison of population distributions in spatially defined ecological niches were performed.The morphological comparisons of both discrete and morphometric characters showed no differences among A. parvum ticks from Argentina and Brazil. The intercrosses and backcrosses showed evidence of pre- and post-zygotic compatibility between the two groups. No significant differences in environmental traits were found which would justify the separation of the records of A. parvum in distinct groups. Although the gene flow between the two groups of populations is limited, the absence of reproductive barriers, the lack of significant morphological differences, and the absence of significant differences in the niche preferences indicate that populations of A. parvum from Argentina and Brazil should be treated as a single species. The speciation conjectures suggested by some analyses of mitochondrial DNA sequences were not supported when different lines of evidences were compared.
authors: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria Rafaela, Consejo Nacional de Investigaciones Científicas y Técnicas, CC 22, CP 2300 Rafaela, Santa Fe, Argentina. Electronic address: nava.santiago@inta.gob.ar.
authors: Santiago
authors: S
authors: Nava
authors: Faculdade de Medicina Veterinaria, Universidade Federal de Uberlandia, Av. Pará 1720, Campus Umuarama-Bloco 2T, 38400-902 Uberlandia, Minas Gerais, Brazil.
authors: Monize
authors: M
authors: Gerardi
authors: Faculdade de Medicina Veterinaria, Universidade Federal de Uberlandia, Av. Pará 1720, Campus Umuarama-Bloco 2T, 38400-902 Uberlandia, Minas Gerais, Brazil.
authors: Matias P J
authors: MP
authors: Szabó
authors: Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Kreder 2805, CP 3080 Esperanza, Santa Fe, Argentina.
authors: Mariano
authors: M
authors: Mastropaolo
authors: Universidade de São Paulo, Faculdade de Medicina Veterinária e Zootecnia, Av. Prof. Orlando M. de Paiva 87, 05508-900 São Paulo, Brazil.
authors: Thiago F
authors: TF
authors: Martins
authors: Universidade de São Paulo, Faculdade de Medicina Veterinária e Zootecnia, Av. Prof. Orlando M. de Paiva 87, 05508-900 São Paulo, Brazil.
authors: Marcelo B
authors: MB
authors: Labruna
authors: United States National Tick Collection, Institute for Coastal Plain Science, Georgia Southern University, Statesboro, GA 30460, USA.
authors: Lorenza
authors: L
authors: Beati
authors: Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain.
authors: Agustín
authors: A
authors: Estrada-Peña
authors: Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria Rafaela, Consejo Nacional de Investigaciones Científicas y Técnicas, CC 22, CP 2300 Rafaela, Santa Fe, Argentina.
authors: Alberto A
authors: AA
authors: Guglielmone
mesh_terms: D063147:Animal Distribution; D000818:Animals; D017753:Ecosystem; D005260:Female; D026863:Ixodidae / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics*; D008297:Male; D012098:Reproduction; D013020:South America; D013045:Species Specificity
keywords: Amblyomma parvum; Ixodidae; South America; Species delimitation