Figure 4

Morphogenesis of Temnopleurus toreumaticus from small process detachment to metamorphosis. Light (A to D,G,H) and scanning electron micrographs (E,F). (A’,B’,D’,E’,F’) show higher magnification images in black (A,D) or white broken squares (B,E,F). (A) An eight-armed larva 25 days after fertilization (ventral view). The larva has formed a pedicellaria on the posterior end. A small process (double arrowheads) is visible near the ectoderm in (A’). (B,C) Eight-armed larvae with primary podia 30 days after fertilization: left lateral (B) and posterior (C) views. When the area on the most anterior primary podium was focused on the ectodermal side (white broken square), a small process was identified. The larva has formed three pedicellariae on the dorsal end and a pedicellaria on the right ventral side. (D,E) Eight-armed larvae 31 days after fertilization: dorsal (D) and left lateral (E) views. The area between the left ectoderm and the adult rudiment has become narrow, and a very small hole is present on the left ectoderm between the left post-oral and postero-dorsal arms (asterisk). (F) An eight-armed larva 33 days after fertilization (left lateral view). Tube feet protrude from the opening in the ectoderm (F’). (G) A juvenile 35 days after fertilization (dorsal view). (H) A young adult sea urchin approximately 1.3 years after fertilization (dorsal view). Pe, pedicellaria; Pp, primary podium. Scale bar = 50 μm for (G), 100 μm for (A to F), and 5 mm for (H).