100 
Psyche 
[Vol. 93 
known for any living myzinine genera, probably because of their 
preference for environments unfavorable to fossilization (xeric bio- 
topes or, in the case of Hylomesa, tropical forests), but all of them 
can be easily derived from Geotiphia morphologically (but not from 
Lithotiphia, because of the apomorphic position of the cu-a cross- 
vein). Geotiphia can be characterized in short as an anthoboscine 
with supraantennal tubercles, a position not consistent with the 
current phylogenetic scheme showing synapomorphies for all 
Tiphiidae other than Anthoboscinae and additional synapomor- 
phies for all Tiphiidae except Anthoboscinae and Thynninae 
(Brothers, 1975). An alternative scheme with Myzininae independ- 
ent of other subfamilies (excluding Anthoboscinae and probably 
Metochinae) seems to me more realistic. 
The paleontological records indicate the minimal age of the 
Myzininae as Early Oligocene. The records seem too scanty, how- 
ever, to help in identifying the geographic area where the subfamily 
arose. 
Summary 
Types of the previously described fossil Tiphiidae are studied. 
Two genera and six species are recognized, each species known only 
from the holotype: Lithotiphia Cockerell, with only one species, 
scudderi Cockerell; and Geotiphia Cockerell, with foxiana Cocke- 
rell (type-species), halictina Cockerell, orientalis, n.sp., sternbergi 
Cockerell, and pachysoma Cockerell. The fossils are found to 
represent the most primitive members of the subfamily Myzininae, 
indicating that the subfamily originated from the Anthoboscinae 
independently of the Thynninae, Tiphiinae, and Brachycistidinae. 
Hoplisidea kohliana Cockerell is now determined as belonging to 
the Sceliphronini of the family Sphecidae and will be treated else- 
where. All species mentioned are from the Lower Oligocene of Flor- 
issant, Colorado, except the new one, G. orientalis, which is from 
the ?Upper Oligocene of Sikhote-Alin Mts., Maritime Province of 
USSR. 
