Cydia splendana

Type

Exotic

Taxonomy

Cydia splendana (Hübner) (Tortricidae: Olethreutinae: Grapholitini)

Common names: chestnut fruit tortrix, acorn moth

Synonyms: bicolorana (Tinea), bicolorata (Tinea), glandella (Tortrix), pencleriana (Tortrix), penkleriana (Tortrix), reaumurana (Carpocapsa)

Adult Recognition

FWLFWL:
forewing length; the distance from the base of the forewing to the apex, including fringe
: 6.5-10.5 mm

Forewings are light gray to gray. 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 purplish 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 dark 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 elongate, apically rounded valvaevalva:
an appendage flanking the intromittent organ that is used to clasp the female during copulation
with only a slight constriction of the neck. Female genitalia are characterized by an extremely thin ductus bursaeductus bursae:
a membranous tube connecting the ostium bursae to the corpus bursae
and a large, globose corpus bursaecorpus bursae:
a dilated membranous sac at the anterior end of the bursa copulatrix
with two small horn-like signasignum:
a sclerotized projection or patch on the interior of the corpus bursae
present.

Larval Morphology

The following account is summarized from Brown & Komai (2008).

Mature larva approximately 13-15 mm in length; head light yellowish brown; prothoracic shieldprothoracic shield:
a sclerotized plate on the dorsal surface of the prothorax
and anal shieldanal shield:
a sclerotized plate on the dorsal surface of the last abdominal segment (in larvae)
yellow; body grayish green or yellowish white; pinacula concolorous with body; SV group on A1, 2, 7, 8, 9 numbering 3:3:2:1:1; anal fork is absent. Meijerman and Ulenberg (2000) incorrectly state that an anal fork is present.

Similar Species

Adults may appear similar to those of other Cydia species. Cydia kurokoi is very similar but only occurs in Asia. Cydia fagiglandana is darker overall and lacks a well-defined purplish ocellusocellus:
forewing pattern element - an ovoid region anterior to the tornus; adult head - a simple insect "eye" located dorsal to the compound eye
. Cydia pomonella is a more uniform gray and the ocellusocellus:
forewing pattern element - an ovoid region anterior to the tornus; adult head - a simple insect "eye" located dorsal to the compound eye
is edged with gold or copper scales. A genitalic dissection can be used to confirm identity of the species listed here.

Other tortricid Castanea pests include Cydia fagiglandana, Cydia glandicolana, Cydia kurokoi, Fibuloides aestuosa, and Pammene fasciana. Brown and Komai (2008) provide a description and key to larvae of these species. Cydia splendana larvae can be distinguished by the following characters: whitish abdomen with concolorous pinaculapinaculum:
flattened sclerotized plates on a caterpillar that bear the setae
; distance between V setae on A9 slightly to conspicuously greater than those on A8; number of crochetscrochets:
hooked spines on the prolegs of lepidopterous larvae
on prolegs less than 18; 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.

Biology

The following account is summarized from Bogenschütz (1991).

Cydia splendana completes a single annual generation. Adults are present in June to July in Central and Northern Europe and August to September in Southern Europe.

Females lay eggs singly on young fruit or on leaves near fruit. Early instars tunnel into fruit and feed inside and a single fruit generally supports one larva. Larval-infested fruit drop to the ground early. Overwintering occurs as a late instar lava under bark or in the soil. Pupation occurs the following spring.

Larvae of Cydia splendana are important pests of chestnut (Castanea sativa). Other preferred hosts include Quercus, Fagus, and Juglans.

Host plant	Host plant family	Reference(s)
Castanea sativa	Fagaceae	Bradley et al. 1979Bradley et al. 1979: Bradley, J. D., Tremewan, W. G., Smith, A. 1979. British Tortricoid Moths, Tortricidae: Olethreutinae. The Ray Society, London. 336 pp.; Rotundo et al. 1984Rotundo et al. 1984: Rotundo, G., Giacometti, R., Rotundo, A. 1984. Individuazione degli attrativi sessuali dei torticidi delle castagne mediante studio elettroantennografico e di campo. Bollettino Laboratori Entomologia Agraria Filippo Silvestri. 41: 211-224 [In Italian]., 1985, 1988; Rotundo & Rotundo 1984; Rotundo & Tremblay 1993; DeBouzie et al. 1996DeBouzie et al. 1996: DeBouzie, D., Heizmann, A., Desouhant, E., Menu, F. 1996. Interference at several temporal and spatial scales between two chestnut insects. Oecologia. 108: 151-158.
Castanea sp.	Fagaceae	USDA/APHIS interception; Danilevsky & Kuznetzov 1968; Rotundo & Giacometti 1986; Martin et al. 1998Martin et al. 1998: Martin, A., Baronio, P., Baldassari, N., Rocchetta, G. 1998. I lepidotteri torticidi del castagno ( Pammene fasciana (L.), Cydia fagiglandana (Zel.) e Cydia splendana (Hb.)) valutati come un#39;unica entita di danno. Bolletim Istituto Entomol. quot;Guido Grandiquot; Univ. Bologna. 52: 105-114.
Fagus sylvatica	Fagaceae	Disque 1908Disque 1908: Disque, H. 1908. Versuch einer microlepidopterologischen Botanik. Deutsch Entomologische Zeitschrift Iris. 21: 34-147.
Quercus petraea	Fagaceae	Bradley et al. 1979Bradley et al. 1979: Bradley, J. D., Tremewan, W. G., Smith, A. 1979. British Tortricoid Moths, Tortricidae: Olethreutinae. The Ray Society, London. 336 pp.; Kelbel 1996Kelbel 1996: Kelbel, P. 1996. Damage to acorns by insects in Slovakia: a survey. Biologia (Bratislava). 51: 575-582.
Quercus robur	Fagaceae	Disque 1908Disque 1908: Disque, H. 1908. Versuch einer microlepidopterologischen Botanik. Deutsch Entomologische Zeitschrift Iris. 21: 34-147.; Bradley et al. 1979Bradley et al. 1979: Bradley, J. D., Tremewan, W. G., Smith, A. 1979. British Tortricoid Moths, Tortricidae: Olethreutinae. The Ray Society, London. 336 pp.; Maksimovic et al.1982; Kelbel 1996Kelbel 1996: Kelbel, P. 1996. Damage to acorns by insects in Slovakia: a survey. Biologia (Bratislava). 51: 575-582.
Quercus rubra	Fagaceae	Maksimovic et al. 1982Maksimovic et al. 1982: Maksimovic, M., Milivojevic, B., Pekic, R. 1982. [Pests of the oak acorn in the seedling stand of Kupinska greda.] Zastita Bilja. 33: 221-257 [In Serbo-Croatian].; Kelbel 1996Kelbel 1996: Kelbel, P. 1996. Damage to acorns by insects in Slovakia: a survey. Biologia (Bratislava). 51: 575-582.
Quercus sp.	Fagaceae	Bradley et al. 1979Bradley et al. 1979: Bradley, J. D., Tremewan, W. G., Smith, A. 1979. British Tortricoid Moths, Tortricidae: Olethreutinae. The Ray Society, London. 336 pp.; Kelbel 1996Kelbel 1996: Kelbel, P. 1996. Damage to acorns by insects in Slovakia: a survey. Biologia (Bratislava). 51: 575-582.
Juglans sp.	Juglandaceae	Bradley et al. 1979Bradley et al. 1979: Bradley, J. D., Tremewan, W. G., Smith, A. 1979. British Tortricoid Moths, Tortricidae: Olethreutinae. The Ray Society, London. 336 pp.