Figure 4.

Representation of the known Hox expression domains in the segments ofA. longisetosus, the spidersCupiennius saleiandParasteatoda tepidariorum, and the harvestmanPhalangium opilio.(A) The known Hox expression domains in the mite A. longisetosus. Expression data for pb, Dfd, Scr, and Antp from [30]. Expression data for Hox3 from [59] and Ftz expression from [60]. Question marks for Hox3, Dfd and Antp denote the unknown late-expression patterns in the Te (see text). (B) The known Hox gene expression domains for the spider C. salei. lab, Antp, Ubx-1 and 2 and abd-A expression from [16]; pb, Dfd-1 and 2 and Scr-1 and 2 expression from [61]. Note that Scr-2 expression was not observed in L2; Hox3 expression from [62]; Ftz from [63]; Abd-B from [20]. (C) The known Hox expression domains for the spider P. tepidariorum. lab, Dfd, Scr, Antp, Ubx, and abd-A modified from [21] and pb and Hox3 from [58]. (D) The known Hox expression domains for the harvestman P. opilio, adapted from [18]. Shaded bars indicate weak expression; however, the shaded bar for Abd- B expression in A. longisetosus denotes its early expression in the Te and subsequent clearing from this tissue. abd-A abdominal-A; abd-B, Abdominal-B; Antp, Antennapedia; Ch, chelicerae; Dfd, Deformed; ftz, fushi-tarazu; L1-L4, first through the fourth walking legs; lab, labial; O1-O12, first through twelfth opisthosomal segments; pb, proboscepedia; Pp, pedipalps; Scr, Sex combs reduced; Te, telson; Ubx, Ultrabithorax.