Distribution of mites (Mesostigmata: Laelapinae) associated with species of Oligoryzomys (Rodentia: Cricetidae) in a geographical gradient

SAVCHENKO EKATERINA; MELIS MAURICIO; LARESCHI MARCELA

Congreso; II Virtual Meeting of Systematics, Biogeography, and Evolution; 2021

SBE

Laelapin mites are common parasites of cricetid rodents and worldwide distributed.A comprehensive knowledge of the distribution of both host and mite is needed, especiallywhen factors and patterns of distribution are studied to evaluate variationin the composition and structure of biological communities across space and/or overtime. Although the distribution of the Oligoryzomys species (also known as pygmyrice rats) is broadly known, their associations with laelapids mites are scarce or nullfor some areas in Argentina. In the present study, we report new records of laelapidmites associated with Oligoryzomys favescens and O. nigripes, obtained during collectionscarried out for more than a decade in 35 localities situated between 25 to 35degrees South and from 53 to 58 degrees West in Argentina. We found the same parasiticassemblage of the laelapids species Androlaelaps fahrenholzi, Gigantolaelapswolsohni, Mysolaelaps microspinosus and a new, yet not described species from thegenus Laelaps, independent from sympatric or allopatric distribution of the rodent,its geographical position, or the host species itself. Solely the species Mysolaelapsparvispinosus was restricted to the northeastern and was absent in the central partof the area, even when both rodents were present. In contrast, the species Laelapsschatzi was unique in association with O. avescens, while Laelaps paulistanensiswas exclusive to O. nigripes, regardless of locality. The results support that speciesreect the distribution of each host and together with known reports of Brazil andUruguay, also almost the whole registered distribution of the rodent(s). The exceptionshowed by M. parvispinosus could be more associated with the geographicalgradient. Hence, the majority of the reported mites showed a wide distribution inArgentina, some extending more than 1,500 km. This indicates a strong host-miteassociation and a deep coevolutionary history, especially for the Laelaps paulistanensis,L. schatzi and their correspondent rodent species.