Cylas formicarius
| Literature database |
|---|
| 118 articles sorted by: |
| • year (descending) |
| • research topics |
| • countries/regions |
| • host plants |
| • list of natural enemies |
Author(s): Juliana Cardona-Duque, University of Puerto Rico
Source: IPM Images
Cylas formicarius (Fabricius, 1793) - (sweet potato weevil)
The weevil is an important and widespread pest of sweet potatoes. The adult feeds on the stems or young leaves and breeds in the tubers or stems, preferring the former. It also infests the stored tubers. Losses can exceed 50% and total crop losses have been reported. In addition, root quality is reduced because infested tubers produce bitter tasting sesquiterpines. Other plants of the genus Ipomoea are also attacked, as are some related species. These can serve as hosts when sweet potatoes is out of season.
The origin of the weevil is not clear but it has invaded several countries, e.g. Japan (first record in 1903) or U.S.A. (first record in Texas in 1890), and is still under quarantine in several regions. Insecticides are mainly used for control and sanitation (removal of infested plants) is also recommended. Several other control strategies are under development, like the sterile insect technique. Pheromone traps are effective for monitoring.
| Vernacular names | |
|---|---|
| • Deutsch: | Zweifarbiger Süßkartoffelkäfer |
| • English: | sweet potato weevil |
| • Español: | picudo de la batata gorgojo del camote |
| • Français: | charançon de la patate douce |
The adult lays single eggs near the border between roots and stem, after having chewed into the plant tissue. The development from egg, through 3 larval stages, to mature adult usually lasts around 5-6 weeks and it can complete 5-8 generations in a year. The adults remain inactive during the winter.
The larvae are legless and the adult weevil is 5-8 mm long. It has an ant-like shape. The head is black, thorax and legs are orange or reddish brown and the elytra and abdomen are dark metallic blue.
Synonyms:
Cylas turcipennis
- Other images of Cylas formicarius (Wikimedia Commons, IPM Images, Flickr and PaDIL - click to enlarge)
larva
damage on sweet potato
infested sweet potato tuber
head
pronotum
posterior end
