REVIEW OF THE EXTINCT FAMILY 
SYNTONOPTERIDAE (ORDER UNCERTAIN)* 
By Frank M. Carpenter 
Museum of Comparative Zoology 
Harvard University, Cambridge 
MA 02138, USA 
The family Syntonopteridae was named by Handlirsch in 1911 for 
a new genus and species, Syntonoptera schucherti, from the Upper 
Carboniferous of Mazon Creek, Illinois. Although the unique spec- 
imen on which the species was based consisted of only a wing frag- 
ment, the presence of several intercalary, triad veins was of unusual 
interest. During the 75 years that have passed since then, only six 
additional specimens of the family have been found (Carpenter, 
1938, 1944; Richardson, 1956), all of them in the Mazon Creek beds. 
The latest of these specimens was sent to me for study by Dr. E. S. 
Richardson, Jr., a few months before his death, and I have only 
recently had the opportunity to study it and prepare illustrations. 
While working on this fossil, I decided to reexamine at the same 
time the other five specimens in the family known to me. A review of 
these specimens is included here, followed by revised diagnoses of 
the family and of the two known genera. 
Genus Syntonoptera Handlirsch, 1911, p. 299. 
Type species: S. schucherti Handlirsch, 1911. Type specimen, no. PM0019, Pea- 
body Museum, Yale University. 
This genus was based on a single specimen consisting of the 
reverse half of an incomplete fore wing (Fig. 1). As preserved, the 
specimen is 80 mm long but the complete wing was probably nearly 
100 mm long. It lacks the proximal and distal areas of the wing, as is 
often the case with insects preserved in concretions. It does show 
clearly, however, the triad branching of MA, MP, and CUA. The 
distal part of RS, which presumably had a triad also, is not pre- 
served. Handlirsch’s figure (1911, p. 3) is correct in most respects 
’•'Research supported by National Science Foundation Grant DEB 8205398, 
F. M. Carpenter, Principal Investigator. 
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