گزارش جنس Quadracus Keifer, 1944 و گونه ی (Q. urticae (Acari: Diptilomiopidae از ایران

The family Diptilomiopidae Keifer, 1944 is differentiated from the other two families of Eriophyoidea by its large gnathosoma compared to the body, chelicerae abruptly curved and bent down near the base, and the longform oral stylet. The family Diptilomiopidae includes more than 63 genera and 467 species worldwide. To date, seven species of this family have been identified in Iran: two species, Diptacus giganthorhynchus (Nalepa, 1892) and Diptacus prunorum (Keifer, 1939) from the subfamily Diptilomiopinae, and five species, Rhinophytoptus nemalobos Lotfollahi et al., 2014, Rhinotergum cerasifoliae Petanovic, 1988, R. schestovici Petanovic, 1988, Rhyncaphytoptus ficifoliae Keifer, 1939 and Brevulacus salicinus Soika et al., 2017 from the subfamily Rhyncaphytoptinae. Herein, the genus Quadracus belonging to the subfamily Rhyncaphytoptinae and Q. urticae is recorded for the first time from Iran. Until now five species have been described from this genus worldwide. In late August 2017, plant samples of Nettle, Urtica sp. (Urticaceae) in Sari county, Mazandaran province were taken. By using a washing method, eriophyoid mites were extracted from the plants, prepared, slide mounted and identified as Quadracus urticae Keifer, 1944. Females of this genus have coxal setae 1b, femoral setae on both legs, dorsal annuli uneven, broad centrally, presenting an irregular serrate profile in lateral view. Some of diagnostic characters of Quadracus urticae are as follows: anterior lobe of prodorsal shield short, broad, blunt; disc slightly raised and enclosed by curved lines; dorsal tubercles 19 µ apart, on rear margin, setae sc 24-25 µ long, projecting forward and out. With 25-26 dorsal annuli, 81 ventrasl annuli and 6 semiannuli between coxisternal plates and coverflap. Coxisternal plates sculptured with lines and dots. The length of setae c2, d, e and f are 7-8, 73-76, 15-18 and 26-30 µ respectively; setae h1 absent. Coverflap with 9 striae and setae 3a 14-15 µ long. It shoud be mentioned that Keifer (1944) had described the empodium of the first leg of this species as 5 rayed, while the empodiums of the first and second legs in Iranian specimens are 6 and 5 rayed respectively (Difference in number of empodium rays could be as internal species variation). Furthermore, a transfer line between admedian lines has been seen in Iranian specimens, probably is because of pressing the specimens during preparing slides.