Biology Reference
In-Depth Information
Myzocallis boerneri
Stroyan
This species, presumably of southern European origin,
infests chestnut-leafed oak (
Quercus castaneifolia
),
Chinese cork oak (
Q. variabilis
), cork oak (
Q. suber
),
Lucombe oak (
Q
.
DESCRIPTION
Apterous female:
2.0-3.2 mm long (dwarf summer
form half-size); yellowish green, coated with white
flocculent masses of wax; siphunculi pore-like; cauda
small, rounded and often inconspicuous.
hispanica
'Lucombeana') and
Turkish oak (
Q. cerris
). It occurs locally in parks,
botanic gardens and arboreta in northern Europe but
does not occur on native oaks. The alatae are relatively
small (1.3-2.2 mm long) and mainly yellow (cf.
Myzocallis castanicola
).
×
LIFE HISTORY
Black, oval eggs are deposited on beech twigs during
the autumn and hatch in the following spring. Colonies
of aphids, which reach the peak of their development by
early summer, then develop on the shoots and underside
of leaves amongst accumulations of white wax. Winged
forms appear after two wingless generations, and these
spread infestations from place to place. In mid-summer,
dwarf apterae are produced and these undergo a period
of aestivation before giving rise to sexual forms.
Colonies eventually die out as winter eggs are laid.
Myzocallis castanicola
Baker
Widely distributed and locally common on oak
(
Quercus
) and sweet chestnut (
Castanea sativa
) but not
an important pest. Alatae (2.2-2.6 mm long) are deep
yellow to brown, with black, bar-like markings and
black siphunculi.
Myzocallis schreiberi
Hille Ris Lambers &
Stroyan
Minor infestations of this local, southerly distributed
species occur on holm oak (
Quercus ilex
). The aphids,
which are entirely parthenogenetic, occur on the
underside of the leaves; they may be found throughout
the year.
DAMAGE
Infested foliage becomes coated with masses of sticky
honeydew, upon which sooty moulds develop. Attacked
leaves become curled; they may also turn brown around
the edges and die prematurely.
Sarucallis kahawaluokalani
(Kirkaldy)
syn.
Tinocallis kahawaluokalani
(Kirkaldy)
Crape myrtle aphid
An eastern Asian pest of crape myrtle (
Lagerstroemia
indica
), which has been accidentally introduced to
various parts of the world (including parts of Europe
and North America) where the exotic ornamental tree is
now grown.
Phyllaphis fagi
(Linnaeus) (
132-133
)
Beech aphid
A generally common pest of beech (
Fagus sylvatica
),
and frequently injurious to nursery trees and hedges;
infestations also occur on Persian iron wood (
Parrotia
persica
). Widespread in Europe; also present in North
America.
132
133
132
Colony of beech aphid (
Phyllaphis fagi
).
133
Beech aphid (
Phyllaphis fagi
) damage to leaves of
Fagus
.
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