wingspan : 75/84 mm
Heliconius cydno is an extremely variable butterfly, and the presently described ssp and forms are probably not very reliable.
all we can say is :
- East of Reserve, and at 1400 m, we found exclusively yellow form (las Juntas - page 992) ;
- West of the Reserve, at see level, exclusively white forms (Calderón - page 999) ;
- between the two : - at 6/800 m, we found about 50% white and 50% yellow forms (on this page),
- and farther West, at 7/900 m, the ratio was two white for one yellow (Alto Tambo - page 916) ;
- and at los Cedros, 1200 m, near Chontal, many yellow forms, and just one white one, (los Cedros - page 424).
it is can also be noted that the HW border varies:
- far from Colombia (Bilsa and los Cedros) - from wide to very wide,
- close to Colombia (las Juntas, Lita, Alto Tambo, Calderón) - from almost absent to narrow, except in Lita where it can be wide.
on this page males individual variations.