Fig. 4 in Kinetid in larval cells of Spongillida (Porifera: Demospongiae): tracing the ancestral traits

Fig. 4 Ultrastructure of the kinetid in larval cells of Lubomirskia baikalensis, longitudinal plane. a–c Series of consecutive sections through a cell. d–g Sections through the kinetid of different cells. Scale bars a–d, f, g 200 nm; e 250 nm. Abbreviations: afb, upper filamentous bundle; axs, axosome; bf, basal foot; bfb, basal filamentous bundle; c, centriole; cm, central microtubules; fb, fibrillar bridge; fr, fibrillar root; ftr, filamentous train; k, kinetosome, pc, points of connection of transition fibres to the plasma membrane