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 27 Raphidioptera The ventral side of tarsomeres 1–3 is densely covered with hairs. Tarsomere 4 is very short and largely concealed between the two lobes of the heart­shaped tarsomere 3 ( Aspock and Aspock 1991 ).