1967] 
Mockford — Electrentomoid Psocids 
1 6 1 
cus alettae. It occurs to very different extents in the different groups, 
and probably represents repeated parallel occurrences. 
The families of electrentomoid psocids are arranged on the dendro- 
gram (fig. 104) in order of appearance of various structures. The 
numbers in the internodes of the dendrogram refer to these structures 
listed in the explanation. The precise phylogenetic relationship be- 
tween the Manicapsocidae and Compsocidae cannot be established 
with information now at hand. The two groups are apparently very 
close, and additional information may allow them to be united. 
The fossil forms Electrentomum and P cirelectrentomum are not 
yet well enough known to be placed with certainty in this scheme. 
They apparently belong either in the Manicapsocidae or Compsocidae, 
in one of the two possible positions indicated on the dendrogram. 
The positions of the Troctopsocid genera within their family require 
explanation. At the first dichotomy, Protroctopsocus retains the ap- 
parently plesiomorphous traits of closed pterostigma, a row of spines 
on the anterior carina of the first femur (shared with Compsocidae, 
Amphientomidae, and some Psocomorpha) , and 15 antennal segments 
(shared with Nanopsocetae, Manicapsocidae, and some Amphiento- 
midae). It is specialized in form of the T-shaped sclerite and in 
possession of an m-cu crossvein in the forewing. At the next dicho- 
tomy, Troctopsoculus retains pretarsal claws alike, while its antennae 
are reduced to 1 1 segments. The remaining branch has pretarsal 
claws dissimilar while retaining 13 antennal segments. 
Certain major changes in classification of the Psocoptera are called 
for by the phylogenetic scheme proposed above. For example, the 
Troctomorpha and Psocomorpha cannot be retained as taxa at the 
same heirarchic level. I believe that these ideas should receive the 
benefit of thoughts of other psocid investigators before such changes 
are proposed. 
Literature Cited 
Badonnel, A. 
1951. Ordre des Psocopteres, in Grasse, P., Traite de Zoologie, 10, 
fasc. 2:1301-1340. 
Banks, N. 
1930. Some new neotropical neuropteroid insects. Psyche 37:183-191. 
Carpenter, F. M. 
1933. The Lower Permian insects of Kansas. 6. Proc. Amer. Acad. 
Arts Sci. 68:411-503. 
Enderlein, G. 
1911. Die fossilen Copeognathen und ihre Phylogenie. Palaeontograph- 
ica 58:279-360, Pis XXI-XXVII. 
Hennig, W. 
1966. Phylogenetic Systematics. Urbana, 263 pp. 
