On the life cycle and parasitism of the trombiculid mite Hirsutiella hexasternalis (Kudryashova, 1998) (Acariformes, Trombiculidae)


  • Andrey B. Shatrov Zoological Institute of the Russian Academy of Sciences, 199034, Universitetskaya nab., 1, St-Petersburg, Russia




individual development, morphology of larvae, host-parasite interaction, Trombiculidae


Post-larval life cycle, larval morphology and histology of the sites of the larvae feeding were investigated in the trombiculid mite Hirsutiella hexasternalis (Kudryashova, 1998) based on the material firstly collected from West Siberia (Tyumen province) from the voles Myodes rutilus (Pallas, 1779). Duration of the nymphal developmental stages generally corresponds to those of other trombiculid mites with the average values of 19 and 13 days for proto- and tritonymphs, respectively. Duration of active deutonymphal stage varies greatly and allocated between 12 and 31 days. Adult mites live much longer, up to eleven months. Larval morphological characters studied by SEM correspond to those of the first descriptions of this species. The stylostome developed in the host skin during larval feeding was investigated using histological methods. The stylostome belongs to the epidermal type and its characters do not correspond to stylostomes studied so far in other trombiculid species. The stylostome is a uniformly wide whitish structure with neither longitudinal nor transverse stratification. It may demonstrate pale-pink staining along the central canal and at the proximal and the distal ends. The central canal opens freely to the underlying tissue and may contain cell debris. Beneath the stylostome, a differently developed feeding cavity containing lymphoid cells may be observed. The host skin demonstrates thickening of the epidermis at the site of attachment, hyperkeratosis as well as dilation of the terminal blood vessels. The characteristics of this trombiculid species are discussed. It is shown, in particular, that morphologically closed species of trombiculid mites reveal noticeable differences in the characters of the life cycle as well as in the stylostome formation.


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How to Cite

Shatrov, A. B. . (2018). On the life cycle and parasitism of the trombiculid mite Hirsutiella hexasternalis (Kudryashova, 1998) (Acariformes, Trombiculidae). SOIL ORGANISMS, 90(3), 157–170. https://doi.org/10.25674/n3jj-5656