Embryonic expression of orthodenticle homologues in the head of P. tepidariorum.
(A to E) Expression of Pt-otd1 during head development. The arrowheads in D and E point to expression in the brain anlage underneath the non-neurogenic ectoderm. (F to J) Expression of Pt-otd2 during head development. Arrowheads in F to J denote Pt-otd2 expression in the non-neurogenic ectoderm, which ends up in the median eye anlagen. All embryos are shown in frontal aspect. The developmental stage is indicated in each panel in the lower left corner.