splendid tamarisk weevil Coniatus splendidulus
beetles, weevils (Order Coleoptera Linnaeus, 1758) snout beetles or weevils (Family Curculionidae Latreille, 1802)
USA Not Approved
Canada Not Approved
🌍 Native Range

Mediterranean

🌿 Hosts in North America

Saltcedars (Tamarix spp.)

🔍 Description and Life Cycle

Overwintering adults emerge in early spring and feed on the tips of new saltcedar shoots. After mating, females lay eggs near stem tips or on flower buds. Eggs are small, yellow, and oval-shaped. Larvae are highly cryptic, closely resembling the green scale-like leaves of saltcedars, albeit with black head capsules. They feed on saltcedar foliage and flower tissue through four instars. Larvae pupate within woven baskets attached to saltcedar leaves. Adults are ~3 mm long with robust bodies, large eyes, thick legs, and thick snouts pointing strongly downward. The elytra have distinct grooves. Adults vary from mottled brown to iridescent green. Because larvae and adults can be difficult to find, searching for the presence of pupal baskets is often the best way to confirm the insect’s presence. There may be 3–4 generations per year, though the adults of each generation are capable of living >12 months. Adults overwinter in plant litter beneath saltcedars. 

Impact

Larvae and adults feed on saltcedar foliage. Newly defoliated plants are straw-colored and quickly refoliate while plants that have been defoliated multiple times may die back, leaving dead gray branches. 

📄 Reference

Bean, D.W. and T.L. Dudley. 2023. Saltcedar Biocontrol Agents: History and Ecology in North America. In: R.L. Winston, Ed. Biological Control of Weeds in North America. North American Invasive Species Management Association, Milwaukee, WI. NAISMA-BCW-2023-33-SALTCEDARS-A. https://bugwoodcloud.org/resource/files/28116.pdf