Live Appearance and Habitat
Female scale cover dark grey, body and eggs yellow. On stems / bark of trees, or seasonally on fruit.
Diagnosis
The presence of perivulvar pores distinguishes D. ostreaeformis from D. perniciosus. In addition, the pygidial gland spines of ostreaeformis anterior to L1 and L2 are slender and fimbriate.
Source: [ScaleNet](http://scalenet.info)
Strucutre Female scale gray, circular, moderately convex, exuviae subcentral; scale of the male elongate, exuvia near one end (Ferris, 1938a). Female scale circular, slightly convex, grayish-brown in colour, dark in the central part and turning light towards the margin, the margin sometimes with a white border; exuviae eccentric; first exuvia light-brown in colour, the second brown; diameter of the scale about 1.5 mm. Male scale oval, grayish-green in colour, almost white on the margins. Length about 0.6-0.8 mm. (Borchsenius, 1935). Female scale circular, somewhat convex, dark gray; in male smaller and slightly elongate (Takagi, 1958).
Keys
Miller & Davidson (2005). Kosztarab 1996: 575 (female) [Northeastern North America]; Danzig 1993: 179-182 (female) [Europe]; Tereznikova 1986: 97-98 (female) [Ukraine]; Chou 1985: 311 (female) [Species of China]; Danzig 1980b: 340 (female) [Far East of USSR]; Kosztarab & Kozar 1978: 173-174 (female) [Hungary]; Bazarov & Shmelev 1971: 211 (female) [Central Asia]; Brookes & Hudson 1968: 91 (larva) [Australia]; Brookes & Hudson 1968: 91 (female) [Australia]; Reyne 1957: 33 (female) [Netherlands ]; Zahradnik 1952: 114-115 (female) [Czech Republic]; Balachowsky 1950b: 404-405 (female) [Mediterranean]; Balachowsky 1948a: 90 (female) [World]; Lupo 1948: 174 (female) [Italy]; Ferris 1942: 40 (female) [North America]; Borchsenius 1938: 142 (female) [Far East of USSR]; Borchsenius 1935: 127-128 (female) [Former USSR]; Britton 1923: 371 (female) [U.S.A.: Connecticut]; Leonardi 1920: 29-30 (female) [Italy]; Lawson 1917: 217 (female) [U.S.A.: Kansas]; Newstead 1901b: 81 (female) [England]; Newell 1899: 4-5 (female) [North America].
