Valid Names Results

Quernaspis quercus (Comstock, 1881) (Diaspididae: Quernaspis)

Nomenclatural History

• Chionaspis quercus Comstock 1881a: 319. Type data: UNITED STATES: California, San Fernando Valley, on Quercus lobata.. Holotype, fossil, Type depository: Washington: United States National Entomological Collection, U.S. National Museum of Natural History, District of Columbia, USA; accepted valid name Illustr.
• Fundaspis quercus (Comstock, 1881); MacGillivray 1921: 338. change of combination
• Jaapia quercus (Comstock, 1881); Lindinger 1931: 44. change of combination
• Pinnaspis quercus (Comstock, 1881); Lobdell 1937: 78. change of combination
• Quernaspis quercus (Comstock, 1881); Ferris 1937: SI-119. change of combination
• Chionaspis (Fundaspis) quercus Comstock, 1881; Fulmek 1943: 24. change of combination
• Chionaspis (Quernaspis) quercus Comstock, 1881; Merrill 1953: 31. change of combination
• Quernaspis kuercus (Comstock, 1881); McDaniel 1973: 397. misspelling of species epithet

Common Names

• Oak scale McKenz1956

Ecological Associates

Hosts:

Families: 2 | Genera: 4

Foes:

Families: 1 | Genera: 1

Geographic Distribution

Keys

• MillerDa2005: pp.29-31 ( Adult (F) ) [Field Key to Economic Armored Scales]
• MillerDa2005: pp.20-21 ( Adult (F) ) [Armored Scales]
• Koszta1996: pp.408 ( Adult (F) ) [Key to the genera of the subfamily Diaspidinae]
• Howell1981a: pp.618 ( First instar ) [Key to 1st instars of Quernaspis]
• TakagiHo1977: pp.46 ( Adult (F) Adult (M) Immature (F) Immature (M) ) [Key to species of Quernaspis]

Remarks

• Systematics: Quernaspis quercus is separable from Q. insularis in having more dorsal submedian macroducts on abdominal segments 3-5 (especially 5) and more submarginal macroducts on abdominal segment 4. It is easily separable from Q. quercicola because the median lobes in Q. quercus are fused, while those in Q. quercicola are separated on the apical half (Takagi & Howell, 1977). Quernaspis quercus should not be confused with its junior secondary homonym Chionaspis quercus Kuwana (=Chionaspis kuwanai).
• Structure: Adult female scale white, oystershell-shaped, 1.5-2.5 mm long with yellow or tan terminal exuviae. The body is reddish-orange. Male scale cover white, elongate, feebly carinate with a terminal exuviae (Gill, 1997).
• Biology: According to Riley (1903) the oak scale overwinters as adult females or partly grown females in California; eggs are laid; male "larvae" and pupae have been collected as late as August. We believe that the overwintering stage must be adult females since males were not found in winter. (Miller & Davidson, 2005).
• Economic Importance: Miller & Davidson (1990) list this insect as a pest. Herbert (1936) reported the oak scale as causing damage to oaks in California and New Mexico. Essig (1915) gave control suggestions, indicating economic importance in California. Apparently it rarely reaches pest proportions. Miller and Davidson (1990) consider this species to be an occasional pest. (Miller & Davidson, 2005).
• General Remarks: Detailed description and illustration by Takagi & Howell (1977). Description and illustration of first instars by Howell (1981a).

Illustrations

Citations