昆虫

http://www.tolweb.org/Arthropoda

Hexapoda(六足类)

Crustacea(甲壳类)

                                               Pauropoda(少脚纲) 

 Myriapoda(多足类)                Diplopoda(倍足纲)       

                                               Chilopoda(唇足亚纲)             

                                               Symphyla(综合纲)

                                              

                                              Arachnida(蛛形纲)  

 Chelicerate (螯肢)                Eurypterida(板足鲎亚纲)      

                                               Xiphosura(剑尾亚纲)             

                                               Pycnogonida(海蜘蛛亚门)

Trilobites(三叶虫纲)