The Description of a Marine Fishes Cestode with the Discussion on the Third Nutrition Manner

Abstract

The authors investigated the marine fish cestodes in Zhanjiang 2000s at the coast of South China Sea. Many specimen of fish cestodes were collected, in which 27 samples collected from Navodon sp. are belonging to Genus Anchistrocephalus. The description of the cestode is as follows: middle worm, with a length of 10~382, proglottids numbered 35~931. Biggest width of the worm is 4.28. Scolex Rectangle, measured 0.478~0.612×0.350~0.484, with an apical disc, 0.197~0.313 near to the disc there are 10 rows of staggering hooks. Neck absent. Taped structure with distinct segmentation, the ratio of width and length of proglottid is not definite. Immature proglottid measured 0.201~0.823×0.331~1.187, while mature proglottids 0.473~0.909×0.829~2.561, gravid proglottid 0.196~0.702×1.483~3.505. Male organs: numerous testes irregularly shaped located in medullary abdomen both side and gathered in the end of the proglottid; cirrus sac is liking a long peared shaped, 0.447 ~ 0.535×0.123 ~ 0.145, cirrus pore alternated both sides irregularly. The cirrus slender, measured 0.330~0.434, with denseness spines on it. The diameter of cirrus is 0.063, open hole, 0.048. Female organs: ovary posterior, measured 0.290~0.388×0.190~0.308, medullary. Vitelline glands distributed both side near the discharge tube follicle, the uterus is tube like, opens in the central abdomen and did not contact the genital pore, numbered 39~84, measured 0.052 ~ 0.062×0.031~ 0.037. For lacking documents the species cannot be identified to species. The special condition of the cestode is that it discharge eggs rather than gravid proglottids and the empty proglottids keep on the body and are absorbed gradually. And this would be a new nutrition manner for Animalia, and it is called by the authors. As we know animal nutrition manners are mainly phytotrophic and heterotrophic at present shown by all scientific documents, but the authors stated here the third one which is suggested to be named as autotrophy (self-absorption) based on the research. Many animals such as sea squirt, frog even human being carried on this nutrition manner.