Exotic
Cydia kurokoi (Amsel) (Tortricidae: Olethreutinae: Grapholitini)
FWLFWL:
forewing length; the distance from the base of the forewing to the apex, including fringe
: approx. 10 mm
Forewings are light gray and brown. The distaldistal:
farthest from body, distant from point of attachment
one-third of the wing is marked with a dark-brown to black subtriangular patch that surrounds the ocellusocellus:
forewing pattern element - an ovoid region anterior to the tornus; adult head - a simple insect "eye" located dorsal to the compound eye 
. Hindwings are grayish brown.
Male genitalia are characterized by the absence of an uncusuncus:
a sclerotized process which is fused to the posterodorsal margin of tergum IX
and sociisocii:
a pair of lightly sclerotized setose lobes
; and distally rounded valve with a well-developed cuculluscucullus:
the distal portion of the male valva
. Female genitalia are characterized by a sclerotizedsclerotized:
hardened; usually in reference to larval structures or adult genitalia 
basal portion of the ductus bursaeductus bursae:
a membranous tube connecting the ostium bursae to the corpus bursae
and two small, tack-like signasignum:
a sclerotized projection or patch on the interior of the corpus bursae
in the corpus bursaecorpus bursae:
a dilated membranous sac at the anterior end of the bursa copulatrix
.
The following account is summarized from Brown & Komai (2008).
Mature larva with head yellowish brown; prothoracic, anal shields pale yellowish brown; body whitish, with conspicuous, darker pinaculapinaculum:
flattened sclerotized plates on a caterpillar that bear the setae
; SV group on A1, 2, 7, 8, 9 numbering 3:3:2:1:1; anal fork absent.
See Komai & Ishikawa (1987) for detailed figures of larval chaetotaxychaetotaxy:
the arrangement of setae (in reference to Lepidoptera larvae), often depicted on a "setal map"
.
Adults may appear similar to other species of Cydia, including C. pomonella and C. splendana. A dissection can be used to confirm identity.
Other tortricid Castanea pests include Cydia fagiglandana, Cydia glandicolana, Cydia splendana, Fibuloides aestuosa, and Pammene fasciana. Brown & Komai (2008) provide a description and key to larvae of these species. Cydia kurokoi larvae can be distinguished by the following characters: whitish abdomen with darker pinaculapinaculum:
flattened sclerotized plates on a caterpillar that bear the setae; D2 pinaculapinaculum:
flattened sclerotized plates on a caterpillar that bear the setae fused to each other on A9; all three L setae on same pinaculumpinaculum:
flattened sclerotized plates on a caterpillar that bear the setae on A9; distance between V setae on A9 greater than on A8; 25-35 crochetscrochets:
hooked spines on the prolegs of lepidopterous larvae 
on abdominal prolegs; anal combanal comb:
a toothed structure on the last abdominal segment used to eject frass away from the feeding larva; also termed "anal fork" 
absent.
The following account is summarized from Komai & Ishikawa (1987).
Cydia kurokoi completes one generation per year. Adults are present in August and September. Larvae tunnel into and feed inside chestnuts. Overwintering occurs in leaf litter as a late instar.
This species is a pest of chestnuts in Japan. Larvae have also been recorded on Quercus.
| Host plant | Host plant family | Reference(s) |
| Castanea crenata | Fagaceae | Komai & Ishikawa 1987 |
| Castanea mollissima | Fagaceae | Komai & Ishikawa 1987 |
| Castanea seguinii | Fagaceae | Komai & Ishikawa 1987 |
| Castanea sp. | Fagaceae | Komai & Ishikawa 1987 |
| Quercus acutissima | Fagaceae | Komai & Ishikawa 1987 |
| Quercus sp. | Fagaceae | Oh et al. 2001Oh et al. 2001: Oh, K. S, Bae, Y. S., Park, J. D. 2001 Moth pests of Quercus (Fagaceae) cone. Korean Journal of Entomology. 31: 221-224. |
View full screen host table here
Cydia kurokoi occurs in China, Korea, and Japan.
