Cryptococcus fagisuga Lindinger

(Fig. 45, distribution map Fig. 89K)

Coccus fagi Bärensprung, 1849: 174 . Coccus fagi (Bärensprung); Walker 1852: 1086. Cryptococcus fagisuga Lindinger, 1936: 444 (replacement name).

Field characters: Live adult female bright yellow, nearly hemispherical, enclosed in felted, filamentous ovisac of white wax.

Microscopic diagnosis: Slide-mounted adult female subcircular or broadly oval, 0.5-1.0 mm long; derm remaining membranous throughout life. Antennae stub-like, each 1‒3 segmented. Pro- and mesothoracic legs absent; each hind leg reduced to an oval cluster pore plate. Anal ring bearing 4 setae and small pores and surrounded by 6 or 8 large setae.

Dorsum. Setae conical, scattered. Macrotubular ducts of 1 size, and microtubular ducts present throughout. Multilocular disc-pores absent.

Venter. Setae hair-like. Spiracles heavily sclerotized, each with 3–6 associated quinquelocular disc-pores. Quinquelocular pores present as group in area of anal ring; others present mostly in marginal areas of venter. Macrotubular ducts of 1 size present throughout, and microtubular ducts present along margin. Cruciform pores absent.

Distribution: Cryptococcus fagisuga is a species of Palaearctic origin, now known from 40 countries in the Nearctic and Palaearctic regions (García Morales et al. 2016). In Iran, it has been recorded from Gilan and Mazandaran provinces (Moghaddam 2009).

Host-plants: The scale is oligophagous, having been recorded on host-plants in two genera belonging to the families Fagaceae ( Fagus spp.), and possibly Pinaceae ( Pinus sylvestris) (García Morales et al. 2016); however, Kosztarab & Kozar (1988) regarded the latter as a very doubtful record. In Iran, it has been found on Fagus orientalis ( Fagaceae) (Moghaddam 2009).

Economic importance: In association with canker fungi, Neonectria spp. (Ascomycota, Nectriaceae); C. fagisuga causes extensive damage to native beech trees in the northeastern United States (Miller & Miller, 1993a), whereas in its natural range the beech trees are tolerant of the fungi. The scale is of no economic importance in Iran.

Natural enemies: None recorded in Iran.