Laelaps cf. L. paulistanensis (Acari: Mesostigmata) ectoparasite of Oligoryzomys spp. (Rodentia) in the Argentine Río de la Plata basin: a model to discriminate cryptic species,explore patterns of distribution and to handle zoonosis.

CARLOS GALLIARI; MARCELA LARESCHI; SAVCHENKO EKATERINA; ULYSES F.J. PARDIÑAS; MELIS MAURICIO

Buenos Aires

Congreso; II Congreso Internacional de Zoonosis. IX Congreso Argentino de Zoonosis; 2018

Facultad Ciencias Veterinarias, UNLP

Laelapid mites are common ectoparasites of rodents, distributed worldwide. Wild rodents mayharbour many zoonotic agents and can also play an important role as reservoir hosts for vector-borne agentsof diseases, e.g. Rickettsia spp. The appearance of several pathogenic agents, mainly in mites belonging to thefamily Laelapidae, has been recently confirmed. However, there is still a lack of information regarding SouthAmerica, especially Argentina. Pathogens used to be vector specific. Thus, when zoonotic studies areconducted, accurate taxonomic identification of ectoparasites may uncover the presence of possible crypticspecies. The distribution of the rodents of the genus Oligoryzomys is relatively well known in Argentina,especially in the Parana-Paraguay river basins. Particularly, Oligoryzomys flavescens and Oligoryzomys nigripesoccur both separately or in sympatry. That constitute a good model for parasite-host-pathogen studies in ageographical range. In order to analyse the presence of probable cryptic species and identify patterns ofdistribution by using morphometric analyses, we study the complex Laelaps cf. L. paulistanensis on O.flavescens/nigripes in different locations.Material and Methods: Multivariate morphometric analyses were conducted on 42 features of each mite. Theexploratory analyses were carried out using the software PAST© Principal Component and Statistical analysisPAST©, to see patterns of morphological differences between hosts and/or geographical differentiation (moreinformation in Fig.1).Two groups (Fig.2) related to geographical distribution were detected, showing no differencesbetween hosts. Mites from the south are smaller and have larger distance between Jv2 epigynal setae thanthose from the north. Our results suggest that cryptic species may occur. Further molecular studies mayconfirm our hypothesis. Moreover, a deeper examination for another ectoparasites is highly recommended.The ability to improve mite identification which acts as potential vector for pathogens helps to predictdistribution areas of zoonotic agents.