Thaumatotibia leucotreta (Meyrick) (Tortricidae: Olethreutinae: Grapholitini)
Common names: false codling moth (FCM)
Synonyms: roerigii (Thaumatotibia)
FWL: 7.0–8.0 mm (males); 9.0–10.0 (females)
Adults of Thaumatotibia leucotreta are sexually dimorphic, and the two sexes differ in overall size, wing shape, and male secondary sexual characters. Male forewings are triangular with an acute apex, while female forewings are more elongate with a rounded apex. Both sexes exhibit a combination of the same forewing pattern elements: a small white dot near the end of the discal cell; a patch of raised, usually rust or orange colored scales near the middle of the wing; a distinct question mark-shaped band of dark scales along the termen; and a semicircular band of dark scales in the middle of the costa. Males are easily distinguished by a semicircular pocket of opalescent scales at the distal end of vein CuA2 on the hindwing, tufts of modified scales on the hind tibia, and an enlargement of the inner apical spur on the hind tibia. Males lack a forewing costal fold.
Male genitalia are characterized by a rounded tegumen lacking an uncus or socii, large rounded valvae, and a tapered aedeagus that is upcurved distally. Female genitalia are characterized by a semicircular sterigma, narrow ductus bursae, and large rounded corpus bursae with a pair of thorn-shaped signa.
The following account is summarized from Gilligan et al. (2011c)Gilligan et al. (2011c):
Gilligan, T. M., Epstein, M. E., Hoffman, K. M. 2011. Discovery of false codling moth, Thaumatotibia leucotreta (Meyrick), in California (Lepidoptera: Tortricidae). Proceedings of the Entomological Society of Washington. 113: 426-435..
Last instar larvae are approximately 12–18 mm long with a yellowish brown to dark brown head and prothoracic shield. The abdomen is orange to pink with large pinacula that are darker than body color. See below for a detailed description of larval chaetotaxy.
The semicircular pocket of scales on the hindwing can be used to separate Thaumatotibia leucotreta males from all other North American tortricids. Many species of Cryptophlebia have similar scale pockets, but no species of Cryptophlebia occur in North America. A dissection can be used to confirm female identity.
Thaumatotibia leucotreta larvae can be distinguished from those of many other North American tortricids by the following combination of characters: L-pinaculum on T1 enlarged, extending beneath and beyond (posterad of) spiracle; D1 and SD1 on A9 on same pinaculum, separate from D2; L group on A9 trisetose; anal comb present with 2–10 teeth. Other larval characters include: SD2 on A1–8 highly reduced or appearing absent; SV groups on A1, 2, 7, 8, 9 with 3:3:2:2:1 setae; spiracle on A8 displaced posterad of SD pinaculum; D2 setae on A9 on shared mid-dorsal "saddle" pinaculum; V setae on A9 slightly further apart than those on A8. The anal comb may be greatly reduced in some individuals.
Larval characters listed here are not completely diagnostic, and T. leucotreta larvae are difficult to separate from Cochylini larvae, which can share the same set of character states (e.g., enlarged L-pinaculum on A9, spiracle on A8 displaced posterad, anal comb present). Two possible distinguishing features are SV counts of 3:3:2:2:2 and a bisetose L-group on A9 in many Cochylini.
In Florida, Pseudogalleria inimicella and Gymnandrosoma punctidiscanum frequently come to lures for T. leucotreta.
Thaumatotibia leucotreta is widely distributed across Africa and has been reported from approximately 40 countries on the African continent. It is not considered established outside of Africa; although it is commonly intercepted during quarantine inspections in the United States and Europe. It was detected in a pheromone trap in Ventura County, California in 2008, although it does not appear to have become established (Gilligan et al. 2011cGilligan et al. 2011c:
Gilligan, T. M., Epstein, M. E., Hoffman, K. M. 2011. Discovery of false codling moth, Thaumatotibia leucotreta (Meyrick), in California (Lepidoptera: Tortricidae). Proceedings of the Entomological Society of Washington. 113: 426-435.).
The following account is summarized from Gilligan et al. (2011c)Gilligan et al. (2011c):
Gilligan, T. M., Epstein, M. E., Hoffman, K. M. 2011. Discovery of false codling moth, Thaumatotibia leucotreta (Meyrick), in California (Lepidoptera: Tortricidae). Proceedings of the Entomological Society of Washington. 113: 426-435..
Thaumatotibia leucotreta is not known to diapause, and development is continuous with adults present year-round. As many as 10 generations are possible per year in South Africa. The absence of a diapause may lead to host shifts and varied developmental rates in times of drought or when preferred host plants are unavailable.
Females deposit eggs singly or in small groups on the surface of smooth fruit. A single female on average may produce between 87 and 456 eggs in her lifetime (with a maximum of 799). On fruit, larvae tunnel into the pith or feed beneath the surface. On cotton (Gossypium sp.), larvae mine the wall of the boll and later move into the center of the boll to feed on the seeds. Larvae complete five instars. Last instar larvae exit the fruit or boll, drop from the host plant, and pupate in a silken cocoon in the soil, under leaf litter, or in bark crevices.
Larvae cause significant damage by feeding directly on fruit or bolls. Feeding in citrus fruit (Citrus spp.) can result in premature ripening and fruit drop as well as secondary infection by fungi. Larval feeding in cotton results in secondary infection by fungus and bacteria, causing rotting of the bolls. Feeding in avocado fruit (Persea americana) results in lesions on the fruit and secondary infection by bacteria and fungi. Chemical control of this species is difficult due to the highly polyphagous, internal feeding larvae, and crop losses can be as high as 10–20% during serious citrus infestations. Control of false codling moth in South Africa is achieved through a combination of chemical control, mating disruption, attract and kill, natural enemies, and sterile insect technique (SIT).
Larvae of T. leucotreta are highly polyphagous and have been recorded feeding on more than 50 species of plants in over 30 families. In Africa, false codling moth is a serious pest of citrus, cotton, and avocado. It has also been reported causing serious damage to corn (Zea mays), guava, macadamia (Macadamia spp.), mango (Mangifera spp.), peach (Prunus persica), and other horticultural crops.
False codling moth is one of the most commonly intercepted tortricids on pepper (Capsicum annuum) and eggplant (Solanum melongena) at United States ports-of-entry.
Authors: KA Austin, TM Gilligan, ME Epstein
Content last updated May 2025
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