Noctuidae: Psaphidinae: Nocloini





Lythrodes radiatus Smith

Lythrodes radiatus Smith, 1903, Trans. Amer. Ent. Soc., 29: 206.

Diagnosis: Lythrodes radiatus is an attractive, small species from the southwestern United States. The forewing is cream-yellow in color with pink-red stripes between the veins. The reniform mark is double and consists of two diffuse white dots. The orbicular mark is also a diffuse white dot, but is sometimes not visible. The basal, antemedial, medial, postmedial, and subterminal lines are absent. There are a series of dull brown rectangles in the fringe terminating the red stripes. The hindwing is yellow-white. The ventral sides of both the forewing and hindwing are completely unmarked.

Distribution: Lythrodes radiatus is found primarily in southern Arizona. However the species is also known from eastern San Bernardino County in southern California and from the state of Chihuahua in Mexico. Individual variation exists in the apparentness of the reniform and orbicular marks. Females are slightly larger than males on average. Adults have been collected from middle July to middle September.

Identification Quality: Excellent

Larva: Unknown

Foodplants: Unknown

Lythrodes radiatus

Lythrodes venatus

Lythrodes radiatus and venatus are very similar superficially. The best feature separating the two species is size; radiatus is consistently smaller than venatus. The average forewing length from base to apex of radiatus is 9.32 mm in males and 10.68 mm in females. The average forewing length for venatus is 12.41 mm in males and 12.77 mm in females. I have not seen any overlap in size, although the possibility cannot be ignored. There do not appear to be any full-proof differences in maculation between the two species. The red stripes of venatus tend to be broader and slightly duller and darker than in radiatus. The orbicular and reniform marks of venatus are usually (but not always) more conspicuous than those of radiatus. I have not found any consistent differences between these two species. The male clasper of venatus tends to be slightly larger than in radiatus, but this structure tends to be variable. The only consistent difference is in size, reflecting the size differences of the adults.

Similar Species

Lythrodes venatus