Paradoxical molting process in Orthezia urticae and other coccids (Arthroidignatha: Gallinsecta) with notes on systematic position of scale insects

Abstract

Process of transformation in legs and antennae, which takes place in Orthezia urticae (Linnaeus, 1758) in course of molt from one instar to another, disagrees with modes of life of these instars. Each molt from one actively feeding instar to another (these are two first instars of male and all instars of female) is accompanied with deep degeneration, dedifferentiation, new differentiation and subsequent growth of each appendage; proximal segment of each appendage newly grows in an unusual inverted condition and everts only during ecdysis. Unlike this, quiescent instars of male molt like most other insects, so that molting processes do not cause immobility of their appendages. Examination of some other coccid species allows to assume that this alternation of molt modes is usual for Gallinsecta. Possibly, this character is initial for Gallinsecta and is connected with existence of leg-less feeding instars in non-related representatives. To describe processes which take place at metamorphosis, new terms for preimaginal instars of Pterygota are introduced. New taxa names PSYLLALEYRODA taxon nov. and APHIDOCOCCA taxon nov. are suggested.