title: Sexual reproduction in the monogenean Diclidophora merlangi: tissue penetration by sperms.
abstract: Copulation between pairs of adult Diclidophora merlangi detached from the host was frequently observed. The spined penis of one animal always attaches to a second worm at a latero-ventral position posterior to the genital openings. There is no vagina. The sperms travel between the cells of the recipient to reach the seminal receptacle. The ultrastructure of the sperm is described. Positions of adult D. merlangi on the gills of the host would facilitate pairing for sperm transfer.
mesh_terms: D000818:Animals; D002467:Cell Nucleus; D003094:Collagen; D005260:Female; D005407:Flagella; D008297:Male; D008854:Microscopy, Electron; D008870:Microtubules; D008928:Mitochondria; D010413:Penis; D012098:Reproduction; D012723:Sex; D013094:Spermatozoa / Q000502:physiology* / Q000648:ultrastructure; D014200:Trematoda / Q000502:physiology*; D014621:Vagina
chemical_list: D003094:Collagen