Fig. 3 in Morphology of larval and postlarval stages of Priapulopsis bicaudatus (Danielssen, 1869) (Priapulida) from the north atlantic ocean

Fig. 3. Lorica: tubuli and frontal plates. A. Fine structure of a tubulus. B. Two frontal plates (fp1, fp2) are present frontal of the dorsal/ventral plate (dvp). C. A pair of laterofrontal plates (lfp) is visible in some specimens. The margin (ma) between frontal plates 1 and 2 is very prominent. D. The folded lateral plates may extend beyond the frontal margins in the closed lorica. E. Frontal view showing the frontal plate 2 and one laterofrontal plate. The sublateral (slp) and midlateral (mlp) plates do not have frontal plates. F. Frontal view on almost closed lorica, showing the prominent margin between the two frontal plates. All images by SEM. A from larva 10 of V13478, B from V13483, C from larva 2 of V13488, D-F from three different specimens of V13494.