PHYLUM ARTHROPODA 



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per). li, Hcmiptera (Icafhopper). Hemiptcrans have sucking mouth parts (C). Wingless 

 forms in each order inchide tlie camel cricket (£) and the bedbug (D). Other orders in- 

 clude the Blattaria (cockroach, Fig. 16.17) and the Isoptera (termite, Fig. 17.18). 



Figure 16.26. The major orders of the Endopterygota. The coleoptera (beetles) have 

 thick, rigid forewings. 1 he Lepidoptera (butterflies and moths) have scales on the wings 

 and sucking mouth parts. The Hymenoptera (bees, ants, etc.) have membranous wings 

 with few veins. The Diptera (flies) have two wings, the hindwings being reduced to bal- 

 ancing organs. 



Neopterans are divided into the Exopterygota and Endopterygota. 

 In the former, as in the Paleoptera, the wings appear in juvenile forms 

 as external wing buds (Fig. 16.24) that become larger at each molt, 

 finally becoming full-sized wings. Such development is part of a pattern 

 called incomplete metamorphosis and the young are called nymphs. The 



