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gin of male-killing in the genus Rickettsiaand
indicated possible horizontal transfer of
Rickettsiabetween the two hosts (von der
Schulenburg et al., 2001).
In A. bipunctata, little is known regarding
the mechanism by which male offspring are
killed early in embryogenesis. Infection has
no effect on larval emergence or develop-
ment rate; however, infected females pro-
duce fewer progeny and do not live as long
as uninfected females (Hurst et al., 1994).


PROTOZOA.The gregarine Gregarina
ruszkowski and the microsporidium Nosema
coccinellaewere detected in A. bipunctatacol-
lected in Poland. The microsporidium was
found to infect the gut of only one of 168
beetles (Lipa et al., 1975). For a description of
this gregarine and microsporidium, see the
section on Coccinellabelow.


FUNGI.During a field study in Poland, B.
bassianawas detected in hibernating adult
beetles from nine coccinellid species, includ-
ing A. bipunctata(Lipa et al., 1975). Several
specimens collected in spring were totally
covered with mycelium, suggesting that B.
bassianaplays an important role in the mortal-
ity of overwintering beetles (Lipa et al., 1975).
Two other parasitic fungi have been
recorded from Adalia. These include a species
of Laboulbeniain Adaliaspp. in France (cited
by Drea and Gordon, 1990) and Hesperomyces
virescens from hibernating A. bipunctatain
England (Weir and Beakes, 1996). The effect
of these fungi on beetle mortality during
hibernation has not yet been studied.


Coccinella: predators of aphids

PROTOZOA.Several species of gregarines have
been reported from Coccinella collected in
Asia and Eastern Europe, suggesting that
gregarines are common in these hosts.
However, little is known regarding the effect,
if any, that gregarines have on the predation
efficiency of infected coccinellids. Gregarina
coccinellae (synonym: Gregarina barbarara)
was originally described from Coccinella
septempunctataL. and Myrrha octodecimguttata
(L.) collected in Poland and the Soviet
Union. It was later found infecting


Exochomus quadripustulatusL. and Harmonia
quadripunctata (Pontoppidan) (Lipa et al.,
1975). Immature stages develop within the
midgut epithelial cells and mature sporonts
are found in the gut lumen, where as many
as 100 individual gregarines are observed.
This gregarine species is reported to exert
some harmful, but unspecified, effects on the
life processes of the host. Gregarina hyashiiis
morphologically similar to G. coccinellae. This
gregarine was reported in Coccinella transver-
salis(Fabricius). Early development occurs
within the midgut epithelial cells and an
increase in basal lamina suggests that there is
a change in the secretory habits of the
infected cells (Sengupta and Haldar, 1996).
The gregarine G. ruszkowskiLipa (synonym:
Gregarina katherina) was reported in
C. septempunctataand C. quinquepunctataL.
from Poland but has also been found in
A. bipunctataand E. quadripustulatus(Lipa et
al., 1975). A fourth species, Gregarina dasgup-
tai, is found in C. septempunctatacollected
from tea plants in West Bengal, India
(Mandal et al., 1986). A fifth species,
Anisolobus indicus, is morphologically similar
to gregarines of the genus Gregarinaand is
reported in C. septempunctata collected in
India (Haldaret al., 1988). Further work is
needed to determine the effects of gregarines
on Coccinellaand other related beetle genera.
The microsporidium N. cocinnellae was
originally described from the coccinellids C.
septempunctata, M. octodecimguttata and
Hippodamia tredecimpunctataL. (Lipa, 1968).
This microsporidium was first detected in
coccinellids from Poland in 1963 and was
subsequently detected in specimens from the
Soviet Union. These two localities are more
than 2000 km apart, giving Lipa (1968) rea-
son to speculate that the distribution of N.
coccinellaecould cover the whole of Europe.
N. coccinellaewas later found to infect A.
bipunctata, C. quinquepunctataand E. quadri-
pustulatus. This microsporidium parasitizes
the gut epithelium, Malpighian tubules,
muscles, nerves and gonads but is not found
in the fat body (Lipa, 1968; Lipa et al., 1975).
In the case of C. septempunctata, only part of
the gut and susceptible organs are infected
(infection is focal). The most intensive infec-
tion is observed in the Malpighian tubules.

Pathogens of Natural Enemies and Pollinators 145
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