Ant-like Flower Beetle
Head: Wide, reddish-brown, covered with silvery hairs.
Antenna: Reddish-brown. 10 segments.
Thorax (Pronotum): Round, light reddish-brown; horn or hood extending over top of the head. The horn is smaller and narrower on the male. Covered with long whitish hair.
Wings (Elytra): Long, light reddish-brown with black marks. Hair long, erect; golden to whitish. Two black spots near base of elytra. On lower half a wide, black V-shape stripe, jagged to zig-zag in appearance, stretches across elytra, reaching side edges. No scutellum (V-shaped area at center base of wings).
Legs: Reddish-brown. Tarsi formula (foot segments front to rear) 5-5-4.
Abdomen: Reddish-brown, streaked darker. 5 segments. Tip brownish, round on male, more pointed or triangular on female. Underside has dense, light hair.
Similar Species: Notoxus monodon is identical, inhabits southern half U.S. only. Two other species present in Ontario N. anchora has a dark stripe down center of elytra, N. subtilis has red thorax and red semicircles on a black elytra. Both are fairly common and much larger 5 to 6 mm long.
Size: 2.8 to 4.2 mm long.
Habitat: Forest edges and open meadows with sandy soil; farm land. Found in shrubs and grasses (prefers Crested Wheat Grass Agropyron).
Food: Scavengers of dead insects, especially Blister Beetles (Meloe) containing cantharidin. Also feed on corn ears, injuring seed and promoting the growth of Fusarium fungi.
Flight Time: May to early September
Life Cycle: Overwinters in leaf litter. Larvae of one Notoxus species reported boring in sweet potato tubers (Cuthbert 1967), so probably eggs are laid in soil. Attracted to lights and cantharidin.
Predators: The Braconid Wasp Centistes (Syrrhizus) agilis parasitizes Notoxus species. This wasp is also is attracted to cantharidin.
Comments: Essex County – Point Pelee and Ojibway Prairies. Kent County – Rondeau Provincial Park. Also Guelph. Uncommon species listed only in Ontario in Canada.
Synonyms: Casey 1895
Notoxus constrictus, Notoxus dinocerus
Annals of the New York Academy of Sciences Late Lyceum of Natural History, 1893-95, Vol. 8: 15 – Coleopterological Notices by Casey, 1895, pp. 756 to 768.
Entomological Society of Ontario, 1971, Vol. 102 by Loan.
Beetles of Eastern North America, 2014 by Evans.