1975] 
Kukalova-Peck — Megasecoptera 
13 
Family Engisopteridae, new family 
Wings : narrow, but not petiolate, almost uniformly broad in distal 
half; posterior margin not undulated. Postcostal vein present; Sc 
terminating shortly before mid-wing, subcostal area relatively broad; 
Rs short; ma area large and rich in long branches, mp area narrow; 
CuA simple, CuP with long branches. Cross veins numerous, inter- 
calated sectors present. 
This family differs from the Arcioneuridae in the broader wings, 
the presence of the postcostal vein, the shorter Rs, and larger ma 
and cup areas. From the primitive family Archineuridae it differs 
in its relatively broad subcostal area, short Sc and Rs and in the 
more nearly parallel arrangement of median and cubital branches. 
The family Engisopteridae has several characteristics of venation 
which are among the most primitive known in the Megasecoptera: 
the relatively broad subcostal area with a series of Sc branches, the 
postcostal vein, and the generalized, richly branched venation (except 
for a simple CuA). These particular features are palaeodictyopterous 
in character, and they are more primitive than their structure in 
Anchineuridae. 
The postcostal vein, which I consider homologous with the “costal 
brace” of Ephemeroptera, is present in almost all Palaeodictyoptera. 
In addition to the Engisopteridae, the vein has been found in the 
Mischopteridae (Carpenter & Richardson 1968, fig. 1, 2), in both 
adult and nymphal wings. It is probable that this inconspicuous vein 
has been overlooked in several other families. The postcostal veins 
are completely reduced in families with a convexly bent Sc at the 
very base, as in Protohymen idae or Alectoneuridae. 
Engisoptera, new genus 
Wings: more or less elongate-oval in shape, narrowed across the 
anal area. C, Sc and R 1 equidistant from each other in the distal 
half of the wing; Sc terminating on C; Rs very remote from Rl, 
sending off 2 short branches; MA, MP, and CuP branches origi- 
nating very anteriorly. Cross veins almost regular. 
The most conspicuous character of this new genus is the branches 
of the main veins originating very anteriorly in the wing. A similar 
branching pattern is present in the hind wings of some Palaeodicty- 
optera. 
The generic name is derived from the Greek words engys and 
ptera (near + wings) and is considered neuter plural. 
Type species: Engisoptera simplices, n.sp. 
