Download N. rufella

A bagworm is
very lovely
ミノムシ
いとあはれなり
Dr. Ryo ARAKAWA
Entomological Lab.
Kochi Univ.
Bagworm （Ｍｉｎｏｍｕｓｈｉ）
Eumeta variegata (=E. japonica)
Bagworm
Ｌarva of psychid moth
(Lepidoptera: Psychidae)
World: １,７００ spp.
Japan: ２１ spp.
Their outbreak has sometimes occurred before and they
are known as the pest of orchard and garden trees.
Common
bagworm in Japan
Eumeta variegata
(Oo-minoga)
ca. 5cm
Winter season
Eumeta minuscula
(Cha-minoga)
ca. 3cm
After diapause termination
No foraging → E. variegata
Overwinter
(diapause) in
silken bag
Pupation
Emergence
Oviposition
Foraging → E. minuscula
Foraging(Larva)
generation
generation
Wi　Sp　Su　Au　Wi　Sp　Su　Au　Wi
Life cycle of E. variegata
Male of E. variegata
pupal sheath
3－4cm
Female after
oviposition
1mm
First instar larva of E. variegata just after hatching
Silken bag making by the 1st instar larva
Silken bag making completed
A species of
parasitic fly has
invaded from
China.
The bagworm
has fear of
extinction in west
Japan.
Jan. 12, 1999
Asahi Shimbun
Adult of Nealsomyia rufella
(Diptera: Tachinidae)
Nealsomyia rufella
♂
♀
Small egg productive type
Oviposit on the leaf foraging by E. variegata larva
Eggs of N. rufella on the chestnut leaf
Eggs of N. rufella
Puparia of the parasitic fly and dead body of bagworm.
Gregarious parasitism
（Sep. 23, 2007 Kochi Univ.）
How did N. rufella invade to Japan?
Classical Biological Control
Invaded pests
permanent control
Introduced natural enemies
from the original habitat of
pests
Classical Biological Control
Icerya pruchasi and Rodolia cardinalis
イセリアカイガラムシとベダリアテントウ
(The end of the 19th century)
Natural Enemies
A variety of natural agents killing another
organisms in nature.
A predator, parasite, parasitoid or pathogen of
another animal, especially an insect. Several
species have been using as the biological control
agents.
Parasitoids
parasitic wasps
parasitic flies
Adults are free living. Females search
hosts and oviposit on, in or near the host.
Larva of parasitoid consumes one or less than
one host for its lifetime.
山東省
Shandong
province
In Shandong, N. rufella was introduced from Southern
China to control E. variegata in about 1990.
Study area in Kochi Pref.
Younger larva parasitized by the fly.
Head width of bagworm
No. of puparia in a bag
Parasitic character of N. rufella
 host
specific
 multivoltine (against univoltine
host)
 gregarious parasitism
Univoltine (年1化性)
Overwinter
Pupa
Adult
Egg
Larva (Foraging)
Overwinter
Multivoltine (多化性)
??
Apr.
Jun.
Aug.
Oct.
Dec.
Life cycles of E. variegata and N. rufella
Feb.
The density of
the bagworm
has extremely
decreased
because of
parasitism by
invaded fly.
Mar. 22, 2000
Kochi Shimbun
Protection of the
bagworm is
expected.
Dec. 14, 2001
Yomiuri Shimbun
Dear bagworm,
are you
extinction?
Jan. 29, 2002
Weekly Playboy,
Japan
100
90.3
％
Parasitism
65.9
65.1
62.3
50
29.5
1.1
Adult emergence
5.6
4.0
4.4
19.3
0
1999
2000
2001
2002
2003
Year
Parasitism and alive of E. variegata
100
Nankoku
％
Nakamura
50
Aki
Sagawa
Kubokawa
0
1999
2000
2001
Year
Parasitism of different area
2002
We found that several indigenous
natural enemies attacked N. rufella
in Kochi Pref.
Brachymeria lasus
(Chalcididae)
Eulophidae sp.2
Eulophidae sp.1
Eulophidae sp.3
Parasitic wasps emerged from the puparium of
N. rufella.
Pteromalidae sp.1
Pteromalidae sp.2
Eupelmidae sp.
Trigonalidae sp.
Parasitic wasps emerged from the puparium
of N. rufella.
Hyperparasitism（高次寄生）
In 2002
・ location 16/24
・Silkenbag 101/854(11.8%)
・Puparium 183/7.297 (2.5%)
Dominant species: Brachymeria lasus
(キアシブトコバチ)
Predation by Jumping Spider (Just after adult
emeregence)
Sep. 9, 2000, Kochi Univ.
Predation by Ants in Silken Bag
Aug. 30, 2007, Kochi Univ.
Present condition of E. vareiagata and
N. rufella in Kochi Pref.
is established.
 E. variegata still alive. (Not
extincion)
 Indigenous natural enemies attack
N. rufella.
 N. rufella
Ecological stability
Conclusion
E. variegata and N. rufella
will continue coexistence.
Wanted
E. variegata
No need
E. minuscula