Insects and their world 





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Fig. 26. An adult ant-lion, of the Order Neuroptera, family 

 Myrmeleontidae 



All adult flies (Diptera) have a sucking proboscis, in which the 

 various mouthparts are combined into a tube. Most often the pro- 

 boscis is soft and sponge-like as in the housefly, and is used for mopping 

 up liquid food. In the flies which pierce the skin of other inseas (Uke 

 the robberflies) or of vertebrates (like the mosquitoes, horseflies and 

 some midges) the fleshy proboscis may conceal sharp, piercing stylets; 

 or the whole proboscis may be hard and sharp, as in the tsetse flies. 



Larval flies have quite a different mechanism. The aquatic larvae 

 that trap organic debris in the water have modified mouthparts of the 

 biting and chewing type; so have the dipterous larvae that Hve in water 

 or soil, and are carnivorous; the larvae of higher Diptera (maggots) have 

 pecuHar mouth-hooks with which they can tear open plant or animal 

 tissues, alive or dead, to release the juices upon which they feed. 



Hymenoptera have both types of feeding in both larvae and adults . 

 The larvae of sawflies are caterpillar-like, and bite and chew vegetation, 

 while the larvae of the other Hymenoptera are soft, helpless grubs, 

 which live either parasitically, or in a mass of food provided for them 

 by their parents; they therefore have reduced mouthparts. Adult 

 Hymenoptera have mouthparts of a chewing type, including well- 

 developed mandibles, but by developing xht galea (a part of the maxilla) 

 into a proboscis many of them are enabled to suck the nectar of flowers 

 (e.g. bees. Fig. 25e). 



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