One new Aculus species (Acari: Eriophyoidea) from Ajabshir, Iran.

Until now about 19 eriophyoid species have been described from plants of family Apiaceae. Among them, three species belong to the Aculus genus including: A. eurynotus (Nalepa, 1894) from Torilis arvensis (Huds.) Link in Rheinbrohl, Germany; A. aphanotrichus (Liro, 1943) from Angelica sylvestris L. in Särkisalo, Regio turkuensis, Finland; A. pimpinellae (Liro, 1941) from Pimpinella saxifraga L. in Hollola, Hatsina, Tavastia australis Natural Province, Finland. Regarding the study of eriophyoid mite fauna of Ajabshir region in Iran, sampling was done on the plants of family Apiaceae during late July 2016. In result eriophyid mites found on the host plant Eryngium thyrsoideum Boiss. and were recovered by means of a modified washing method. The mites were slide mounted according to Baker et al. (1996). All morphological measurements were taken by means of a phase contrast microscope Olympus BX53 according to Amrine and Manson (1996) as modified by de Lillo et al. (2010). The mites identified as a new species of the genus Aculus. Until now 13 of more than 297 Aculus species have been found in Iran and two Aceria and one Shevtchenkella species have been found on Eryngium plants. Among them Shevtchenkella denticulata Lotfollahi, de Lillo & Haddad, 2014 is the only eriophyoid mite found on E. thyrsoideum. So this Aculus sp. nov. is the forth eriophyoid species and first Aculus species from Eryngium plants. The new species compared with all species found on Apiaceae plants and similarities with the species A. aphanotrichus have been found in dorsal semiannuli number, smooth genitalia coverflap and setae sc length. However these two species can be distinguished from each other in the following features: prodorsal shield pattern (smooth in A. aphanotrichus versus with lines made by slight longitudinal bumps in the new species); empodium rays number (5 in A. aphanotrichus and 4 in the new species); setae h1 presence (absent in A. aphanotrichus and present in the new species); setae d length (35 in A. aphanotrichus and 70–80 in the new species). This new species was vagrant on the host plant and no apparent damage was observed