Rhizococcus borchsenii

Rhizococcus borchsenii (Danzig) (Fig. 61, Plate 4D, distribution map Fig. 93E) Acanthococcus borchsenii Danzig, 1975: 45. Eriococcus borchsenii (Danzig); Tang & Hao 1995: 461. Rhizococcus borchsenii (Danzig); Kozár et al. 2013: 416‒418. Field characteristics: Live adult female body oval, completely covered with felted grey ovisac. Microscopic diagnosis: Slide-mounted adult female body elongate oval. Antennae each with 7 segments. Frontal lobe present, frontal tubercle absent. Legs robust; hind coxa and femur with spinulae on anterior surfaces; hind coxa with large group of translucent pores; tibia with 5 setae elongate, not enlarged; tarsus longer than tibia; tarsal and claw digitules longer than claw, slightly knobbed; claw with a denticle. Anal lobes prominent, each lobe with 3 hair-like setae on dorsum, venter with 2 slender hair-like setae and a suranal seta, apical seta normal and elongate. Anal ring with a partial double row of pores and bearing 8 setae. Cauda present. Dorsum with enlarged setae blunt or truncate, normally of 3 sizes: on most segments, each side with 2 or 3 larger setae and some smaller ones, together forming a marginal band, but on posterior most 3 abdominal segments, each side of each segment with enlarged setae forming 1 or 2 irregular rows. Macrotubular ducts present throughout. Microtubular ducts numerous. Venter with smallest size of enlarged setae in a sparse row along body margin and forming a sparse submarginal band. Labium wide; basal segment with 2 unequal pairs of setae, apical segment with 5 pairs of long setae and a pair of short apical setae. Macrotubular ducts of 2 types: (i) larger size numerous along body margin; and (ii) smaller size fewer, present in medial or submarginal areas. Microtubular ducts scattered on margins. Quinquelocular pores forming sparse bands across posteriormost abdominal segments, scattered elsewhere. Cruciform pores present along margins of thorax. Distribution: Rhizococcus borchsenii is a Palaearctic species known from China (Nei Monggol), Mongolia, North Korea, Russia (Primor’ye Kray) and Iran (García Morales et al. 2016), where it has been found in Semnan province (Moghaddam & Mohammadi-Khoramabadi 2015). Host-plants: The scale has been only recorded on Artemisia sp. (Asteraceae) in Iran and elsewhere (Moghaddam & Mohammadi-Khoramabadi 2015; García Morales et al. 2016). Economic importance: Not known as a pest in Iran. Natural enemies: None recorded in Iran.