Fig. 5
Expression of Emx at early developmental stages in embryos of the onychophoran E. rowelli. Anterior is left in a, c–f and up in b; asterisks demarcate the proctodeum, developing limbs are numbered. a Early stage I embryo in ventral view, superimposed light micrograph and DAPI image. Dashed lines indicate the segmental borders, arrowheads point to the expression at the anterior border of the jaw segments. Inset shows the same embryo stained with DAPI. b Late stage I embryo in lateral view, superimposed light micrograph and DAPI image, dorsal is right. Inset shows a light micrograph of the same embryo. c Stage II embryo in lateral view, dorsal is up. d Same embryo as in C, superimposed light micrograph and DAPI image. e Anterior developing limbs of a stage II embryo in lateral view, dorsal is up. Filled arrowheads point to the expression at the anterior border of each segment, empty arrowheads indicate the mesodermal expression in the developing limbs. f Same detail as in E, superimposed light micrograph and DAPI image. Filled arrowheads point to the expression at the anterior border of each segment, empty arrowheads point to the mesodermal expression in the developing limbs. Abbreviations: as, antennal segment; at, developing antenna; cl, cephalic lobe; de, dorsal extra-embryonic tissue; js, jaw segment; jw, developing jaw; sp, developing slime papilla; ss, slime papilla segment; ve, ventral extra-embryonic tissue Scale bars: a, e, f: 200 μm; b–d: 500 μm