鲟科鱼类寄生粘孢子虫二新种(粘孢子虫纲:双壳目:碘泡科)

TWO NEW SPECIES OF MYXOSPORIDIA (PROTOZOA) OF ACIPENSERID FISHES FROM YANGTZE RIVER (MYXOSPOREA: BIVALVULIDA: MYXOBOLODAE)

在长江中游的扬子江白鲟和中华鲟上发现二种粘孢子虫,命名为白鲟碘泡虫,新种和宜都单极虫,新种。

In November 1975 and 1982, two Myxosporidia were found in Psephurus gladius and Aci-penser sinensis from Yangtze River. The descriptions are given below:1. Myxobolus psephurusi sp. nov. (fig. 1-8)Host and locality: Psephurus gladius, Hung Hu (29°30'N, 113°30'E) of Hubei Province.Location: kidneyCyst: oval or elliptical, diameter 50-70 microns.Spore: oval or pyriform in thecal view: fusiform in sutural view; suturalridge is broad and straight. Anterior end is pointed and posterior edge broadly rounded. Intercapsular appendix distinct. Two club-shaped polar capsules are unequal in size. Their coiled filament are well marked and distinct. The sporoplasm contains a large iodinophilous vacuole and two nuclei. 2-4 V-shaped folds at posterior end. Dimensions of fresh specimen: spore length 16.8 (14.4-19.2)μ, width 11(9.6-12.4)μ. Large polar capsule 8.5(7.8-9.6)μ×4.0(3.6-4.6)μ; small one 8.0(6.0-9.0)μ×3.8(3.0-4.0)μ.2. Thelohanellus yiduensis sp. nov.(fig. 9-16)Host and locality; Fry of Acipenser sinensis. y-idu (30°30'N, 111°E) of Middle reaches of the Changjiang (Yangtze river).Location: Gill and skin.Vegetative stages: Cyst rounded with trophozoite of different stage and spore.Spore: long oval in thecal and sutural views with a thin and transparent envelope; sutural ridge straight and distinct. Single polar capsule located at 3/5 position of spore length; coiled filament fine and distinct. Two polar capsule nuclei situated at lateral of polar capsule. Sporoplasm contains a relatively large iodinophilic vacuole and two round nuclei. Dimension of fresh spores: spore with envelope length 41.8(38.69-46.07)μ, width 12.55(10.44-15.53)μ; spore length 31.53(30.55-33.6)μ, width 9.46(7.89-10.69)μ; polar capsules 21.1(18.33-22.91)μ × 7.59(6.62-8.15)μ.Type specimens of the two new species are deposited in the Institute of Hydrobiology, Academia Sinica.