Species name

Diabrotica undecimpunctata tenella LeConte 1858: 88


Common name

Western cucumber beetle


Type locality

California, Fort Yuma


Type depository

MCZ, lectotype, male, verified



Body length 4.8-7.1 mm. Body width 2.7-3.8 mm. Head basic color black. Antennae filiform, bi- or tricolored, antennomeres 1-3 sulphur yellow, antennomeres 4-11 yellow ocher. Maxillary palpi yellow or yellow ocher, labrum black or chestnut. Pronotum yellow or sulphur yellow, subquadrate, bifoveate, with small round foveae, shagreened with minute wrinkles. Scutellum black or amber brown. Elytra green, yellow or rufous, with 12 round black maculae. Elytral epipleura completely yellow, sutural angle of elytra round, punctation scattered, fine. Abdomen yellow. Tarsi black or amber brown, tibiae bicolored yellow, outer edge with piceous or testaceous line, or extensively darkened. Femora bicolored, yellow, darkened with black or brown from 1/2 to 2/3. Aedeagus symmetric, with four internal sac sclerites.


Known distribution



Host plants

Dahlia Cav., Ericameria nauseosa (Pall. ex Pursh) G.L. Nesom & Baird., lettuce, beet, Citrullus vulgaris Schrad. ex Eckl. & Zeyh., Cucumis melo L., C. sativus L., Cucurbita L., Medicago sativa L., bean, pea, cotton, Hordeum sativum Jess., Sorghum L., corn (Zea mays L.), apricot, peach, Solanum elaeagnifolium Cav., S. tuberosum L., Agave shawii Engelm., Cucurbita mixta Pang., Prosopis L. (Clark et al., 2004)


Potential problems with identification

Diabrotica undecimpunctata tenella LeConte can be separated from other subspecies by the following features: abdomen is yellow in D. undecimpunctata tenella, entirely black in D. undecimpunctata undecimpunctata and black in the middle in D. undecimpunctata duodecimnotata; legs, usually only femora, partly pale in D. undecimpunctata tenella, but entirely black in D. undecimpunctata undecimpunctata; spots on elytra in D. undecimpunctata tenella are smaller than in D. undecimpunctata undecimpunctata and D. undecimpunctata howardi. Diabrotica undecimpunctata tenella is smaller and slender than Diabrotica undecimpunctata howardi.