How to Manage Pests

UC Pest Management Guidelines


Pink Scavenger Caterpillar

Scientific Name: Pyroderces rileyi

(Reviewed 2/17, updated 2/17)

In this Guideline:

Description of the Pest (View caterpillar ID key) (PDF)

The pink scavenger caterpillar occurs sporadically in the coastal areas of San Diego, Orange, and Ventura counties. When fully grown, larva is much smaller compared to other orangeworms. Pink scavenger caterpillars have light brown heads, black mouthparts, a dark brown prothoracic shield, and a dark pinkish abdomen.


On orange and lemon trees, the caterpillar is mainly a scavenger, feeding on dry or decaying fruit, dead floral parts, and sooty mold. Look for it mainly among fruit clusters and under sepals. During summer, larvae may feed on the rind of ripe Valencias, often near the stem end or on the sides of fruit in a cluster. The feeding is usually superficial and does not cause appreciable damage. In a few cases, serious damage has occurred similar to that caused by orange tortrix. A heavy infestation may result in fruit drop or decaying fruit during storage.


Insecticide applications are rarely needed.


[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Citrus
UC ANR Publication 3441

Insects, Mites, and Snails

E. E. Grafton-Cardwell, Lindcove Research and Extension Center, Exeter and Entomology, UC Riverside
J. G. Morse, Entomology, UC Riverside
D. R. Haviland, UC Cooperative Extension, Kern County and UC IPM Program
B. A. Faber, UC Cooperative Extension, Santa Barbara and Ventura counties

Acknowledgments for contributions to Insect, Mite, and Snails:
J. Barcinas, E.S.I., Corona, CA
R. Dunn, Badger Farming Co., Exeter, CA
J. Gorden, Pest Management Associates, Exeter, CA
C. E. Kallsen, UC Cooperative Extension, Kern County
D. Machlitt, Consulting Entomology Services, Moorpark, CA
C. Musgrove, retired entomologist, Riverside, CA
K. Olsen, S & J Ranch, Pinedale, CA
N. V. O'Connell, UC Cooperative Extension, Tulare County
P. A. Phillips, UC IPM Program, UC Cooperative Extension, Ventura County
T. Roberts, E.S.I., Corona, CA
T. Shea, UC Cooperative Extension, Riverside County
J. Stewart, Pest Management Associates, Exeter, CA
P. Washburn, Washburn & Sons Citrus Pest Control, Riverside, CA

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