148 R. W. CROSSKEY 
postalar callus 


scutum 

suprasquamal 
ridge 
26 
lower calypter 
21 
tegula 

basicosta 






24 25 27 
Fics 21-27. Taxonomic characters used in the text. 21, postalar callus and surrounding 
structures. 22-25, vestiture of postalar wall and suprasquamal ridge in: 22, forms with 
both areas bare (e.g. Prodiaphania, Rutilodexia); 23, forms with sparse hairing only on 
suprasquamal ridge (e.g. subg. Microrutilia); 24, forms with very long dense hair on 
suprasquamal ridge (e.g. subg. Chrysorutilia, Amphibolia); 25, forms with dense hair 
tuft on postalar wall (Formosia, Formodexia). 26, strongly explanate costal base (e.g. 
Prodiaphania). 27, basal part of wing, showing long wiry setulae on tegula in most 
forms (shaded area indicates the sub-basal dark mark found on the wing of most Ruti- 
liini). 
