Isognathus scyron (Taxonomy)
Transferred to Isognathus by Felder & Felder, 1862, Wien. ent. Monatschr.6: 187. Grote, 1865, Proc. ent. Soc. Philad5: 74, and in several subsequent papers, did not believe that Cramer's figure could be reliably identified with any species of sphingid. However, Grote must never have seen a true scyron, for Cramer's figure is quite a good representation of that species.
Bands on upperside of abdominal distinct. Upperside of thorax and forewings russet-drab-brown. Underside of abdomen dirty white or slightly buff, faintly speckled with russet scales. Outer half of forewing upperside with grey vein-streaks, interrupted by black dots. Forewing upperside with black dash between M3 and CuA1, and another smaller one between CuA1 and CuA2, these dashes situated in a pale russet area that is not clearly defined though obvious, being most distinct between M1 and M3. Forewing upperside without black dashes but with russet area well marked.