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描述了双须骨舌鱼(Osteoglossum bicirrhosum)的外部形态和内部结构,并对其核型进行了分析。通过对试验鱼的观察、测量、解剖和拍照,得到如下结果:双须骨舌鱼为侧扁体型;口上位,口裂大;侧线发达,侧线鳞数35～36;鳍式分别为D43-46,P7,V6,A50-54,C12;体长分别是体高、头长、尾柄长和尾部长的5.34倍、5.23倍、97.62倍和1.82倍,头长分别是吻长、眼径和眼间距的3.95倍、6.04倍和2.96倍,体高是体宽的2.05倍;无雌雄异型现象。胃发达呈U型,幽门盲囊短且粗;鳔1室,与体腔等长且位于体腔上部紧贴脊椎骨。雌、雄性双须骨舌鱼性腺均为单侧性腺,成熟雌鱼所含卵粒数较少,但卵径较大。以肾脏为材料,用空气干燥法制备染色体标本,双须骨舌鱼的染色体数目为2n=56,核型公式为2n=2sm+26st+28t,NF=58,未见异型性染色体。
The external morphology and internal structure of Osteoglossum bicirrhosum were described and their karyotypes were analyzed. By observing, measuring, dissecting and photographing the test fish, the following results were obtained: The double-beaked turtle is flat-sided; the upper part of the mouth is large and the split is large; the lateral line is developed with a lateral line number of 35-36; the fin types are D43-46 , P7, V6, A50-54 and C12 respectively. Body length were 5.34 times, 5.23 times, 97.62 times and 1.82 times of body length, head length, tail length and tail length respectively. Spacing of 3.95 times, 6.04 times and 2.96 times the body height is 2.05 times the body width; no male and female shaped phenomenon. Stomach developed U-shaped, pyloric blind capsule short and thick; 鳔 1 room, and body cavity length and located in the upper body cavity close to the vertebrae. Female and male mustaches tongue fish gonads are unilateral gonads, mature females contain fewer eggs, but larger egg diameter. With the kidney as the material, the chromosomal specimens were prepared by air-drying method. The number of chromosomes was 2n = 56, the karyotype formula was 2n = 2sm + 26st + 28t, NF = 58, and no atypical chromosome was found.