area; larger setae in medial area from anterior
anal plates (Fig. 56, D) to head. Submarginal
tubercles (Fig. 56, F) present or absent. Thick
rimmed disc pores (Fig. 56, I) anterior of anal
plates. Anal plates (Fig. 56, Ki) triangular with
the caudal angle rounded, each plate with 4
apical, 2 subapical setae. VENTER-Antennae 6
or 7-segmented (Fig. 56, 0). Legs without
tibiotarsal scleroses; Claw digitules unequal.
Spiracular furrows 2 or 3 quinquelocular pores
(Fig. 56, P) wide, pores widely spaced.
Multilocular pores (Fig. 56, Q) in transverse
rows on abdomen and in central area of thorax,
most with 10 loculi. Tubular ducts (Fig. 56, S)
sparse on submargin of abdomen, thorax, and
medial area of thorax. MARGIN- Marginal setae,
(Fig. 56, B) straight or slightly curved, with
blunt apices, some thicker than others.
Spiracular setae 3 (Fig. 56, E), median seta 1.5X
longer than laterals.
DISTRIBUTION: Map XXI. Found throughout
the U. S. Foreign: Holarctic, plus Argentina and
Australia.


Map XXI. Distribution of Parthenolecanium corni.


BIOLOGY: According to Williams and
Kosztarab (1972), European fruit lecanium over-
winters in the second nymphal instar on the
twigs and branches and matures in early spring.
In early summer, adult females lay large
numbers of eggs beneath their bodies. After the
eggs hatch, the nymphs migratelo the underside


of leaves where they feed, but before leaf drop
they migrate back to twigs and branches where
they overwinter.
ECONOMIC IMPORTANCE: Economically im-
portant in many situations, especially on or-
namentals where the balance of natural controls
has been hampered by chemical controls.
NATURAL ENEMIES: Numerous parasites are
listed in Peck (1963) and Krombein et al. (1979)
for this scale insect. Some of those common to
this area are as follows: Aphycus annulipes
(Ashmead), FL; Metaphycus pulvinariae
(Howard), cosmopolitan; Cheiloneurus albicor-
nis Howard, LA; Coccophagus lycimnia
(Walker), cosmopolitan; C. scutellaris
(Dalman), FL; Encyrtus bicolor Howard, LA; E.
fuscus (Howard), AL; Eunotus lividus Ashmead,
FL; Microterys flavus (Howard), FL; Pros-
paltella aurantii (Howard), cosmopolitan;
Scutellista cyanea Motschulsky, cosmopolitan;
Tetrastichus minutus (Howard), FL. In northern
California and British Columbia, the parasite
Blastothrix sericea (Dalman) has contributed to a
decline in the economic importance of P. corni
(Bartlett in Clausen ed. 1978). It is likely that
because of taxonomic confusion in the genus Par-
thenolecanium this list of parasites may not be
accurate.
REMARKS: This is one of the most common and
widespread scale insects in the U. S. Because it
exhibits extreme morphological variation from
host to host, many of its host-induced forms have
been described as separate species. It is not possi-
ble to consistently separate P. corni from P.
fletcheri (Cockerell) and P. quercifex (Fitch).
Therefore, these 3 species are referred to as the
"corni complex" (Williams & Kosztarab 1972).
MATERIAL STUDIED: FLORIDA;
Gainesville, 1(1), Diospyros sp., 3-IV-1923, G.
B. Merrill; Jacksonville, 1(1), Liquidambar
styraciflua, 3-III-1981, J. Garbark; Lakeland,
2(2), Pinus sp., 2-IV-1981, Training Class #44;
Live Oak, 1(1), Prunus sp., 28-III-1977, O. P.
Hatch; Port St. Lucie, 1(1), Carya sp.,
28-II-1980, E. W. Campbell; Tavares, 1(1),
Quercus nigra, 2-IV-1981, L. J. Chambliss;
White Springs, 2(2), Myrica cerifera,
21-III-1980, C. Webb.




 PARTHENOLECANIUM FLETCHERI
 (Cockerell)

SYNONYMS: Lecanium fletcheri Cockerell
 1893f:221