Figure 1.
Light microscopy of cresyl-violet stained micrographs of Heteroxenia fuscescens.
a. Cross-section of polyp at pharyngeal level. b. Cross-section of tentacular pinnules. Nematocytes stained red (white arrows), pharynx (ph); epidermis (ep); mesoglea (me), gastodermis (ga), mesenterial filament (mf); gastrovascular cavity (gvc), zooxanthellae (white arrow heads).
Figure 2.
Scanning-electron micrographs of nematocytes within the gastrovascular cavity of Heteroxenia fuscescens.
a. Nematocytes on the gastrodermis (white arrows); insert: cross-section of exposed gastovascular polyp cavity with mesenteries (mf), enlarged area of a indicated by rectangle. b. Enlarged view of a nematocyte, cnidocil (cn).
Figure 3.
Light microscopy of wet mounts of discharged nematocysts of Heteroxenia fuscescens stained by cresyl violet.
a. Atrichous isorhiza nematocysts isolated from polyp cavity, zooxanthellae indicated by arrow. b. Novel type of nematocysts adjacent to surface of tentacular pinnules, zooxanthellae indicated by arrow. c. Enlarged view of a discharged atrichous isorhiza nematocyst-type from the gastrovascolar cavity. d. Novel macrobasic-mastigophore nematocyst-type from pinnules.
Figure 4.
Scanning-electron micrographs of discharged atrichous isorhiza nematocyst of Heteroxenia fuscescens.
a. Whole nematocyst with capsule (cp) and elongated thread tubule. b. Enlarged view of the tip (arrow) of the thread tubule with spines (s). c. Spines along the thread tubule (s).
Table 1.
Size features of Heteroxenia fuscescens nematocysts.
Figure 5.
Scanning-electron micrographs of novel macrobasic-mastigophore nematocyst type of Heteroxenia fuscescens.
a. Whole nematocyst with capsule (cp), spiral shaft and elongated thread. b. Enlarged view of spiral shaft covered with arrowhead-shaped spines (white arrow). c. View of the plain proximal thread tubule. Scale at b also applies to c.