42 BULLETIN 1429, U. S. DEPARTMENT: OF AGRICULTURE 
TIPHIA KOREANA Bohwer 
GENERAL OBSERVATIONS 
During the middle of August, 1923, there were found in a small 1 
locality near Suigen, Chosen, a few individuals of Tiphia which, 
when tested experimentally, oviposited readily upon grubs of Popillia 
atrocoerulea and Anomala sp. Later grubs of P. japonica were pro-' 
vided, and oviposition and development took place normally upon; 
them. However, field collections of parasitized grubs indicated itsi 
true host to be Anomala rather than Popillia. 
• The adult wasps were very rare in the field at the time mentioned 
and only nine females were obtained. Examination on August 12 of 
field grubs bearing eggs or larvse revealed practically all to be in the 
first larval stage, though a few eggs had not yet hatched. The pro- 
portion of Anomala grubs parasitized ranged as high as 76 per cent in 
small lots brought in by the collectors, the general average being 20 
per cent for the area in which the parasite was known to occur. A 
consideration of the foregoing data would indicate that the period of 
adult presence ranged from about July 20 to the middle of August, 
with the peak of oviposition attained in the first week of the latter 
month, and that the few adults collected represented merely the end 
of the period rather than an actual numerical scarcity. A small 
number of cocoons were obtained from field-collected material and 
forwarded to the Riverton laboratory for rearing and liberation. 
LIFE HISTORY 
Unlike the other species of Tiphia discussed in this bulletin, T. 
Jcoreana places its egg dorsally rather than ventrally upon the host, 
and in a crevice on the median line of the third thoracic segment. 
The egg is somewhat dark in color as compared with that of the 
two preceding species. Under relatively high temperature condi- 
tions hatching occurs in five to six days, but the larval stages in thej 
field are prolonged as a result of the rapidly decreasing temperatures 
in the latter part of August and early September. The winter is 
passed in the larval stage within the cocoon. 
The adults of this species are somewhat larger than those of; 
Tiphia popilliavora and T. vernalis; in fact, they are the largest of 
all the species found in Chosen, and this combined with the earlinessi 
of their appearance would seem to handicap it considerably against I 
Popillia japonica in America. With a largely biennial cycle of the 
host, as in Hokkaido, mature grubs would be available for para-j< 
sitism during the period covered by this Tiphia, but very few such 1 
grubs are available in the American infestation. It is therefore seen 
that relatively little effectiveness can be looked for from its intro- 
duction. 
KEY FOR THE DETERMINATION OF TIPHIA ADULTS 
In order to facilitate the identification of the introduced species 
of Tiphia, S. A. Rohwer has prepared the following key. However, 
reference to further detailed description in his papers 6 is advisable. 
In this key the specific characters are inclosed in parentheses. 
8 Rohwer, S. A. Descriptions of three species of Tiphia parasitic on Popillia japonica (Hym.). In 
Proc. Ent Soc. Wash., vol. 26, pp. 87-92, 1924. A new Tiphia from Korea (Hym.). In Proc. Ent. Soc. 
Wash., vol. 29, January, 1927. 
