LARVAL F0RM8 OP" COLEOPTERA 



INTRODUCTION 



(pi. 125j 

 Tlie eok'opterou.s larvae belong to three fundamentally different 

 types. Consequently, in the present synopsis the families are ar- 

 ranged into three different suborders, namely: 



Suborder 1 : Archostemata 



Suborder 2 : Adephaga 



Suborder 3 : Polyphaga 

 According to the views commonl}' lield by entomologists,- only two 

 major divisions of Coleoptera, the Adephaga and the Polyphaga, 

 are recognized. However, the present studies, M'hich intentionally 

 stress larval characters and avoid consideration of imaginal struc- 

 tures, show the necessity of recognizing a third suborder for the 

 inclusion of the Cupedidae and Micromalthidae, whose larval mor- 

 phology isolates them from all other beetles. The term "Archoste- 

 mata," first proposed by Kolbe, is here adopted as the subordinal 

 name for these two families. Although very specialized they are 

 nevertheless so ancient that they must be regarded as the represen- 

 tatives of an almost extinct larval type. 



It is of great interest that several modern entomologists, work- 

 ing exclusively with the imagines, have realized the isolation of the 

 Cupedidae and Micromalthidae; and Dr. AVm. T. M. Forbes, in his 

 paper on Aving-folding patterns of the Coleoptera (Jour. New York 

 Ent. Soc, vol. 34, 1926), has, like the present authors, recognized 

 those two families as forming a separate suborder which he, too, 

 names Archostemata. 



In contrast to the primitive and slightly specialized larval types 

 to which the Polyphaga can be traced, the larvae of the Adephaga 

 possess a complex of highly advanced and derivative characters which 

 probably have been acquired through a long evolutionary process 

 from an unknown primitive larval type somewhat different from the 

 existing primitive Polyphaga larva. However, the well developed 

 and Avell defined tarsus of the Adephaga carrying one or two distinct 

 aiul movable claws may be a primitive character not altered through 

 the course of their development into high specialization. The ancient 

 Archostemata larvae also possess a distinct tarsus and claw and 



^Consult the introduction "Essay on Classification" in C. W. 

 Leng's Catalogue, jop. 3-37, in which a very clear and critical re- 

 view is given of the different systems from the earliest one by Lin- 

 naeus to the one proposed and applied by Leng himself. The bibli- 

 ography is prepared with the painstaking care so characteristic of 

 the iiiifhor. 



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