An ocellar "pupil" that does not change with light intensity, but with theinsect age in Triatoma infestans

The simple eyes (ocelli) of recently emerged adult Triatoma infestans exhib it a narrow elongated "pupil", surrounded by a ring of brown-reddish pigmen t, the "iris". This pupil does not respond to changes in the illumination, but var ies in size after the imaginal ecdysis. This change corresponds, in ternally with the growth of the corneal lens and the associated retina trp to ail age of about 20 days. This has not been previously observed in an in sect. The use of this characteristic for recognising young adults of this s pecies is suggested.