FIGURE 1 in Molecular analysis of six Rhynchospio Hartman, 1936 species (Annelida: Spionidae) with comments on the evolution of brooding within the group

FIGURE 1. Gamete morphology of Rhynchospio cf. foliosa (fixed material). A, B, developed coelomic oocytes. A, external honey-combed surface of oocyte thick envelope. B, optical section of an oocyte, showing 20–30 vesicles (cortical alveoli, ve) associated with inner surface, germinal vesicle (gv) and single nucleolus (nl). C, D, spermatozoa, showing conical acrosome (ac) with a small dark spherical structure in anterior part and a transparent central part, ovoid nucleus (nu), a few spherical mitochondria, and a long flagellum. Scale bars: A–C = 10 µm; D = 5 µm.