Abstract:

Aphids distribute worldwidely as a large group of Hemiptera.There is a close relationship between the aphid and the human.Some aphid species are pests.In China,aphid fauna of many areas have been systemically studied,but few relevant work has been done in Shanghai although it is a rapid economic growth metropolis.In order to grasp insect composition of aphids,the species diversity of aphids with taxa,host plant,infesting location and infesting type was studied in Shanghai based on field investigation and literature analyses.The results showed that 75 species,belonging to 46 genera and 8 families of aphids were found in Shanghai,accounting for 6.8%,17.2%,and 61.5% of known aphid species,genera and families in China,respectively.Although Aphididae contained the maximum known aphid species of Shanghai,it  contributed only 10.0% of the total known species in China.Only one species of Thelaxidae was found in Shanghai.Although only 2 species Phylloxeridae were found in Shanghai,it contributed 50.0% of the total known species in China.The host plants of aphids in Shanghai were diverse at family and genus level,being 83 in genera and 44 in families.The dominant families were Poaceae,Rosaceae,Brassicaceae,Papilionaceae,Salicaceae,Ulmaceae,Asteraceae.They were also the common plants in Shanghai.Among the aphids,Aphididae had the most diverse  host plants,with 59 genera in 30 families,accounting for 71.1%,62.8% of known aphid host plants genera and families in Shanghai,respectively.The host plants of Phylloxeridae and Thelaxidae were very poor,being 2 genera in 2 families and 2 genera in 1 family.The infesting location of aphid was various in Shanghai.Phylloxeridae and Pemphigidae parasitized on root,while the aphids feeding on the twigs,stems and leaves involved multiple families.Aphididae and Pemphigidae had the highest diversity of infesting location.Aphididae,Lachnidae and Chaitophoridae often fed on rich nutrition places such as twigs,stem and leaf.There were three infesting types: notforming galls,forming galls and forming pseudogalls.The main infesting type for aphid in Shanghai was notforming galls.Pemphigidae and Hormaphididae were forming galls.Pemphigidae and Aphididae were forming pseudogalls.Not only forming galls but also forming pseudogalls were specific on one host plant location—the leaves.For the strict specification between aphids and host plants,aphid can have different forms of adaptive mechanism to plants.In some sense,the diversity of the host plants determined the diversity of the aphids in Shanghai,and the climatic environment of Shanghai was proper to aphid survival