西北印度洋鸢乌贼角质颚外形变化的影响因素

根据2019年冬春季(2-5月)中国灯光罩网渔船在西北印度洋生产调查期间采集的1009尾鸢乌贼样本,分析了其角质颚外部形态变化的影响因素.结果表明:角质颚外形特征参数在不同性别、不同胴长组和不同性腺成熟度间均存在显著差异.胴长组201～250mm以及雌性个体性腺成熟度Ⅱ期和雄性个体性腺成熟度Ⅲ期的各特征参数增幅达到峰值...

Factors influencing beak morphology of Sthenoteuthis oualaniensis in the northwest Indian Ocean.

With 1009 Sthenoteuthis oualaniensis samples collected by Chinese light falling-net fishery during February to May in the northwest Indian Ocean, we analyzed the influencing factors of the morphology change of the beak. There were significant differences in the morphologic growth between genders, different gonad maturity stages, and different mantle length. The increment of characteristic parameters growth peaked in the mantle length between 201 and 250 mm, and in the Ⅱ and Ⅲ stages of gonad maturity for females and males, respectively. There was no significant difference in the ratio of morphometric parameters to crest length (CL) between the genders, diffe-rent gonad maturity stages, and different mantle length, except for the ratio of upper hood length to upper crest length (UWL/UCL) and lower hood length to lower crest length (LHL/LCL). The ratio of each characteristic parameter to CL was nearly stable with the change of sex, gonad maturity and mantle length, suggesting consistent growth of each dome of beak. Our results suggested the mantle length of 201 mm to 250 mm seemed to be the threshold for the morphologic growth of beak on the body size, while the gonad maturity of Ⅱ and Ⅲ stages seemed to be the threshold for the morphologic growth of beak on the gonad maturity.