1974] 
Kukalova-Peck — Pteralia 
417 
Fig. 1. Partially fused axillary plate of Boltopruvostia nigra (Palaeo- 
dictyoptera, Homoiopteridae) . Enlarged base of fore wing. Redrawn 
from Kukalova, 1960. API — anal plate; bg — basal groove; CuPl -— 
cubital plate; MP1 — median plate; ScRPl — subcosto-radial plate. Upper 
Namurian, Czechoslavakia. 
tecture of extant Paleoptera. In the Odonata, the thorax and pteralia 
have been discussed in detail by Tannert (1958), Neville (i960), 
and Hatch (1966), but interpretation of these structures is still 
subject to debate. The axillary plate is considered either as the fused 
radio-anal plate, or as a compound structure, with the radio-anal 
plate, axillary sclerites, and subalare incorporated. However, the 
wings of the Odonata are highly specialized and possess many unique 
features and therefore are less suited for comparison with Paleozoic 
orders than the more primitive wings of the Ephemeroptera. The 
pteralia in Ephemeroptera have been recently studied by Brodskyi 
(1970), Matsuda (1970), and Tsui and Peters (1972) (fig. 5), 
but the axillary plate was not described in functional terms; it was 
mostly referred to as “median plate”. In this paper, the terminology 
is derived from Tannert’s (1958) account on the Odonata and the 
respective axillary plates are called by the terms of incorporated basal 
plates of the veins. Since the fossil specimens do not contribute to 
our knowledge of whether the other pteralia are fused with the 
axillary plate, this problem should be considered as fully open to 
future emendations based upon a detailed study of functional mor- 
phology. 
