Growth rules applied to the stage identification of nymphal instars of some mallophagan species (Phthiraptera)

Abstract

Dyar's and Przibram-Megusar's rules were used to check the growth progression of the following biting lice (Mallophaga): Amyrsidea megalosoma and Uchida phasiani (Amblycera: Menoponoidea), Goniocotes chrysocephalus and Zlotorzyckella colchici (Ischnocera: Goniodidae), Lipeurus maculosus maculosus and Reticulipeurus mesopelios colchicus (Ischnocera: Lipeuridae) and Lagopoecus colchicus (Ischnocera: Degeriellidae) — the parasites of pheasants (Phasianus colchicus L.). It was shown that the dimensions of the head and body, particularly the head width, as the most suitable measurements, follows a regular geometrical progression. The calculated values according to Dyar's rule approximate very closely to the observed measurements in all examined species. In the case of A. megalosoma, G. chrysocephalus and L. colchicus — they are identical. Przibram-Megusar's rule revealed one latent division in the head width as well as in body of Z. colchici. In the case of R. m. colchicus only the measurements of body indicate the extra division.