脉红螺形态学参数分析及其交配行为的观察

A Preliminary Study on the Mating Mode and Sexual Choice Before Copulation of Rapana venosa

为探究脉红螺（Rapana venosa）的交配模式及交配前的性选择机制,本实验选取99个脉红螺成体进行形态学测量并分析6个形态参数的相关性。研究发现,脉红螺的壳宽、体螺层高、厣宽和厣高均与壳高有显著相关性（r≥0.8）,与螺旋部高无相关性（r〈0.3）,螺旋部高仅与壳高有弱相关性（0.3≤r〈0.5）;进一步比较雌螺和雄螺的6个形态学参数,发现脉红螺不存在性别二态性现象。在室内养殖池内观察脉红螺交配行为,发现亲螺入池后2~4d,雌螺和雄螺陆续出现交配现象;脉红螺每次交配持续时间均小于96h,其中83.6%的交配在48h内完成;雌螺和雄螺的交配次数均在0~5次之间,交配间隔期在2.67~8.80d之间,且前2次交配的间隔期要长于其他间隔期;未发现脉红螺在交配前以外部形态特征作为选择依据。研究表明,脉红螺属于多雌多雄的混交模式。

In order to explore the mating pattern and the mechanism of sexual selection before copulation in Rapana venosa,six morphological parameters of 99 adult R.venosa were firstly measured and the correlation of six morphological parameters were investigated.The results showed that aperture width,body whorl height,operculum width and operculum height were significantly and positively correlated with shell height,but not spire height.Spire height showed a weak correlation with shell height.Moreover,R.venosa showed no sexual dimorphism in the six morphological parameters.R.venosa began to mate in two to four days after being put into the rearing pond and the copulation behavior was recorded.The duration each mating was within 96 hours and 83.6% of the mating couples finished copulation within 48 hours.The times of mating of R.venosaranged from zero to five and mating intervals ranged from 2.67 to 8.80 days.All in all,R.venosa displayed a promiscuous mating behavior.