FIGURE 18 in Sperm structure in Parasitidae mites (Parasitiformes: Mesostigmata: Gamasina)

FIGURE 18: Trachygamasus sp., DIC (A), TEM (B, C). (A) Isolated spermatozoon with anterior end directed upward. Arrow indicates posterior end of nucleus. (B) Fragment of a late spermatid showing granular, incompletely condensed nuclear material (n), ribbons (rb), subplasmalemmal cisterns (sc), sIBs, and mitochondria (m). Asterisk marks mitochondrion in cyst cell enveloping spermatid. (C) Deferent duct spermatozoon sectioned through nucleus (n) containing chromatin (ch). Ribbons (rb), sIBs with unclear margins and mitochondria (m) are also present. Note sperm plasmalemma (white arrow), longitudinal crests (black arrows) above ribbons, as well as characteristic deep infoldings of plasmalemma and subplasmalemmal cisterns (sc) on both sides of ribbons. Scale bars: 50 µm in (A); 1 µm in (B,C). Abbreviations: ch – chromatin, m – mitochondrion, n – nucleus, rb – subplasmalemmal longitudinal ribbon, sc – subplasmalemmal cistern, sIB – striated inclusion body