PSYCHE 
Vol. 69 September, 1962 No. 3 
THE CYTOTAXONOMY OF THE LARVAE OF SOME 
MEXICAN FRUIT FLIES IN THE GENUS ANASTREPHA 
(TEPHRITIDAE, DIPTERA) 1 
By Guy L, Bush 2 
U. S. Department of Agriculture 
Introduction 
During a study of host relations of the Mexican fruit fly, Anas- 
trepha ludens (Loew), difficulty was encountered in obtaining 
positive identification of tephritid larvae recovered from field infested 
fruit. Existing larval keys based on morphological characters (e.g. 
Phillips, 1946) were not adequate for differentiating between some 
closely related Mexican representatives of the family. Accurate 
identifications could only be obtained by rearing larvae to the adult 
stage. This proved time consuming and increased the chance of 
losing valuable host records when larvae failed to mature. For this 
reason, a preliminary cytotaxonomic study was made on some of the 
more common fruit infesting Anastrepha found in Mexico to see if 
chromosome morphology would be of any use in identifying larvae. 
This method of species differentiation is not new. It has been used 
for many years by plant taxonomists to establish a more natural 
classification within certain groups of plants (Darlington, 1956). 
Its application to animal taxonomy has been somewhat restricted 
owing, in part, to the difficulties of handling some animal material. 
Many of these difficulties have now been eliminated through the use 
of new and improved techniques. A great deal is now known about 
the cytogenetics of animals and particularly of the insects. White 
(1954) has presented an excellent summary of our present knowledge 
of comparative cytology and its application to the study of animal 
evolution and taxonomy, while Patterson and Stone (1952) have 
This study was conducted under the auspices of the United States Depart- 
ment of Agriculture while the author was employed by that organization in 
Mexico, D.F., Mexico, from 1955 to 1957. 
2 Present address: Biological Laboratories, Harvard University. 
Manuscript received by the editor Jan. 28, 1962. 
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