Ultrastructure of attachment specializations of hexapods (Arthropoda): evolutionary patterns inferred from a revised ordinal phylogeny Author R. G. Beutel Author S. N. Gorb text J. Zool. Syst. Evol. Research 2001 39 177 207 journal article 10.1046/j.1439-0469.2001.00155.x 95b3d62f-8fcc-4088-873f-b33f4a63d3fc 2360323 25 Neuroptera (= Planipennia) The tarsus of the middle and hind legs is almost always fivesegmented as in members of other holometabolous groups with the exceptions noted. Modification in number of tarsomeres is only known from the specialized raptorial fore legs of some mantispids ( New 1991 ). No specific adhesive structures are present in members of Sisyridae, Myrmeleontoidea and Ithonidae . An arolium is developed in representatives of other groups ( Fig. 4F ).