Rhizococcus istresianus (Goux)

Moghaddam, Masumeh & Watson, Gillian W., 2024, The Scale Insects Of Iran (Hemiptera: Coccomorpha) Part 3 The Soft Scales (Coccidae) And Other Families, Zootaxa 5542 (1), pp. 1-202 : 134

Rhizococcus istresianus (Goux)

( Fig. 62 , distribution map Fig. 93F )

Eriococcus istresianus Goux, 1989: 19–23 . Rhizococcus istresianus (Goux) ; Kozár et al. 2013: 484‒488.

Field characteristics: Found on the upper leaf surfaces. Live adult female body cream-coloured, covered by a white ovisac.

Microscopic diagnosis: Slide-mounted adult female body oval. Antennae each with 7 segments. Frontal lobes developed, frontal tubercle absent. Legs well developed, meta- and mesothoracic coxae with spinules on ventral surfaces; hind coxa with distinct translucent pores present on dorsal margin; tibiae each with 5 setae, median seta present; tarsal and claw digitules all knobbed apically, longer than claw; claw with a denticle. Anal lobes well developed and slightly sclerotized, dorsum of each lobe with 2 enlarged setae along inner margin and 1 enlarged seta on outer margin; venter of each lobe with 3 long slender setae. Anal ring with 2 rows of pores anteriorly and bearing 8 hair-like setae. Cauda present, strongly sclerotized.

Dorsum with enlarged setae with apices rounded to relatively pointed, except for those on posterior abdominal segments more or less blunt; abundant, but enlarged setae absent from medial area of segment VIII; each segment usually with 1 or 2 setae on each margin. Macrotubular ducts all of 1 size, present throughout except absent from segment VIII. Microtubular ducts scattered throughout.

Venter with mostly hair-like setae, but some enlarged setae present in marginal and submarginal areas. Posterior spiracles slightly larger than anterior ones. Quinquelocular (sometimes trilocular) pores distributed in sparse bands and rows across all segments of abdomen, thorax and head. Macrotubular ducts all of 1 size, scattered. Microtubular ducts scattered throughout. Cruciform pores scattered on submargins from head to abdominal segments.

Distribution: Rhizococcus istresianus is known from France, Greece, Hungary, Türkiye ( Turkey) and Iran ( García Morales et al. 2016), where it was collected from Kermanshah province (Moghaddam 2019).

Host-plants: The scale has been recorded on host-plants belonging to three genera in the families Asteraceae and Cistaceae ( García Morales et al. 2016) ; in Iran, it was found on Carthamus tinctorius ( Asteraceae ) (Moghaddam 2019).

Economic importance: Not known as a pest in Iran.

Natural enemies: None recorded in Iran.

Figures

FIGURE 62. Adult female of Rhizococcus istresianus (Goux).

FIGURE 93. Distribution maps of scale insect species in Iran covered in this work. A, Pulvinaria urbicola Cockerell; B, Pulvinaria vitis (Linnaeus); C, Rhizococcus asperulae Moghaddam; D, Rhizococcus avicennae Moghaddam; E, Rhizococcus borchsenii Danzig; F, Rhizococcus istresianus (Goux); G, Rhizococcus reynei (Schmutterer); H, Rhizococcus saxidesertus (Borchsenius); I, Rhizopulvinaria artemisiae (Signoret); J, Rhizopulvinaria turkestanica (Archangelskaya); K, Saissetia coffeae (Walker); L, Saissetia miranda (Cockerell & Parrott); M, Saissetia oleae (Olivier); N, Sphaerolecanium prunastri (Boyer de Fonscolombe); O, Stotzia ephedrae (Newstead).