Fig. 10
From: An embryological perspective on the early arthropod fossil record
A schematic summary of the identity of anterior segments and their appendages in some of the taxa discussed, modified from [15]. The four illustrations are lined up with homologous segments at the same level. The anterior three are named on the left. The dashed line indicates the border between the prosocerebral domain and the archicerebral domain within the protocerebrum. Abbreviations: aa- antenniform appendage; an1- first antenna (crustacean antennule); an2- second antenna; asc- anterior sclerite; ch- chelicera; ey- eye; fl- flap (includes lobopod limb in Kerygmachela); lb- labrum (hypostome/labrum complex); li- limb (unspecialized walking or swimming limb); mn- mandible; pa- Primary antenna (raptorial limb); pp- pedipalp; sca- sub-chelate appendage