Fig. 2. Expression of AbdB in Artemia. (A) Early AbdB expression in the two genital segments, shortly after these segments have formed (stage L9). (B) Later, stronger AbdB expression restricted to the two genital segments (stage L11). (C) Late expression of AbdB (after stage L13) persists in the differentiated genital segments and also extends anteriorly to cells of posterior thoracic/trunk segments. AbdB expression is never seen posterior to the genital segments. Anterior is upwards.