Integrative taxonomy reveals hidden diversity within the concept of a laelapine mite species (Mesostigmata: Laelapidae) associated with sigmodontine rodents (Cricetidae): description of three new species of Laelaps Koch in the Neotropical region

SAVCHENKO, EKATERINA; LARESCHI, MARCELA

Systematic And Applied Acarology

Systematic and Applied Acarology Society

Año: 2022

1362-1971

Laelapine mites are one of the most common ectoparasites of cricetid rodents. The taxonomical status is unclearof mites reported as Laelaps manguinhosi-like mites, since morphological variation was reported within thespecies in association with taxonomically and ecologically distinct sigmodontine rodents. We analysedmorphological (qualitative and metric variation) and molecular data of four morphotypes of L. manguinhosilikemites collected from three sigmodontine rodents (Cricetidae) of the tribe Oryzomyini (Holochilusbrasiliensis, Nectomys squamipes and Oligoryzomys flavescens) and one of the tribe Akodontini (Scapteromysaquaticus). For better understanding, we defined L. manguinhosi sensu lato as a species concept and limited ina narrower sense L. manguinhosi sensu stricto. The association known from the literature between L.manguinhosi sensu stricto and H. brasiliensis was confirmed and additional information of this mite wasprovided. Mites associated with the remaining rodent species appear to be new species within L. manguinhosisensu lato species complex, here described as Laelaps galliarii sp. nov., Laelaps scapteromyos sp. nov.,Laelaps odysseos sp. nov., parasitizing O. flavescens, S. aquaticus and N. squamipes, respectively.Morphological analysis showed clear separation between the four studied species, with the majority alsosupported by molecular data. These results reinforce previous observations that Laelaps species are specific atleast to the level of the host genus. Phylogenetic analysis based on 18.S-ITS1-5.8S-ITS2 partial gene markersindicate an earlier host-switch scenario between an akodontine associate (L. scapteromyos sp. nov.) and anoryzomyine associate (L. manguinhosi sensu stricto) followed by cospeciation events. Studied morphotypes ofLaelaps were resolved as three separated clades. The basal one included mite species associated exclusivelywith Murinae (Old World) rodents and the other two are specific to Sigmodontinae (New World). The clade ofsigmodontine associates was further divided into a cluster of mites parasitizing semiaquatic rodents and anothercluster comprising mites parasitizing scansorial rodents. The obtained topology indicates that both, thephylogeny of rodent hosts and their ecological traits may play an important role in the coevolutionary processof host-mite relationships.