Do parapatric populations of the ticks Amblyomma tonelliae Nava, Beati & Labruna, 2014 and Amblyomma sculptum Berlese, 1888 (Acari: Ixodidae) hybridize?

EVELINA L. TARRAGONA; PAULA LADO; LORENZA BEATI; ATILIO J. MANGOLD; ALBERTO A. GUGLIELMONE; SANTIAGO NAVA

MEDICAL AND VETERINARY ENTOMOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2023

0269-283X

This work aimed to determine if the tick species, Amblyomma sculptum and Amblyommatonelliae, hybridize along their contact zones in Argentina. Free-living adults and nymphsof A. sculptum and A. tonelliae were collected in seven sampling locations of northernArgentina. In four of them, the two species occur in parapatry (possible hybrid zone)whereas in the other three sites, only one species is known to occur. A total of65 A. sculptum and 65 A. tonelliae from both, allopatric and parapatric populations, wereanalysed. The nuclear (ITS2) and mitochondrial (COI and 12SrDNA) gene sequences ofeach tick were amplified and analysed to verify whether or not they could reveal thepresence of hybrids among the parapatric samples. No morphological and molecular evidencewas found to support the hypothesis of ongoing natural hybridization. Intrinsicpostzygotic barriers may be the cause of lack of gene flow between the two speciesin areas of co-ocurrence. The results can be explained by the length of time the twolineages spent in allopatry since the middle of the Miocene and before their respectivedistribution range expanded again reaching a narrow secondary contact zone.