A new species of Ornithodoros (Acari: Argasidae) from desert areas of northern Chile

Abstract

Ornithodoros atacamensis n. sp. is described from larvae collected on the lizard Liolaemus bisignatusand from free-living adults collected in desert areas from the Pan de Azúcar and Llanos de ChalleNational Parks, in Northern Chile. Additionally, unengorged larvae were obtained from fertilized females,which laid eggs in the laboratory. Morphological and mitochondrial 16S rDNA sequence analyses wereperformed in order to compare this new soft tick species with other congeneric Neotropical represen-tatives. Larvae of O. atacamensis are morphologically closely related to Ornithodoros talaje sensu stricto,Ornithodoros puertoricensis, Ornithodoros rioplatensis, Ornithodoros guaporensis and Ornithodoros hasei, allbelonging to the O. talaje species group. The larval diagnostic characters for this species are a combina-tion of a large pyriform dorsal plate with a length of approximately 300 m, 17 pairs of dorsal setae withfive central pairs, hypostome with apex pointed and dental formula 2/2 in most rows, 3/3 apically, andcapsule of the Haller?s organ oval in shape without reticulations. Phylogenetic analyses inferred from themitochondrial 16S rRNA gene and a Principal Component Analysis based on morphometric charactersprovide additional support to the description of O. atacamensis as an independent lineage within thegenus clustering within the O. talaje species group.