FIGURE 1 in Embryology of the spider crabs Leurocyclus tuberculosus (H. Milne-Edwards & Lucas 1842) and Libinia spinosa (H. Milne-Edwards 1834) (Brachyura, Majoidea)

FIGURE 1. Schematic representation of the different periods of embryonic development of Leurocyclus tuberculosus and Libinia spinosa. A, Period I, segmentation. B, Period II, presence of the embryonic primordium. C, Period III, the optic lobe can be clearly discerned. D, Period IV, pigmentation of the optic lobe. E, Period V, appearance of chromatophores. Ab, abdomen; Annt, antennula; Ant, antenna; Bl, blastomere; E, embryonic primordium; Ex, external coverings; F, funiculus; In, internal coverings; MI, maxilliped I; MII, maxilliped II; MA, mouth appendages; O, optic lobe; P, pigmentation of the optic lobe; SpCr, spherical chromatophores; StCr, star-chromatophores; Y, yolk.