The pupa of Chironomus decorus Johannsen, 1905 – additional description and an unusual sexual dimorphism

Abstract

In his original description of Chironomus decorus, Johannsen included a brief description of the pupa but with insufficient detail to differentiate it from other North American species, particularly those of the decorus-complex. In this note, further information of pupal characters, mostly derived from specimens reared from egg masses, are given which allow separation of these pupae from those of some other species, e.g., presence of frontal warts, and in the case of the males, to permit accurate identification by the presence of a small secondary tubercle.