南海外海鸢乌贼耳石形态特征分析

Statolith morphology of purpleback flying squid(Sthenoeuthis oualaniensis) in the offshore South China Sea

2012年9月-10月于南海外海采集鸢乌贼（Sthenoteuthis oualaniensis）样本455尾,其中体背部具发光器个体427尾,体背部无发光器个体28尾。检测发现,鸢乌贼耳石样本具明显的背区、侧区、吻区和翼区结构,其中背区略小,而侧区和翼区宽大,吻区较长窄。鸢乌贼的胴长（ML）与耳石总长（TSL）之间呈二次函数关系（P〈0.05）。根据胴背部发光器,结合分层聚类分析和灰色星座聚类法分析,南海海域采获的鸢乌贼可分为3个类群：中型群、微型群、X3型群。对中型群和微型群进行种群差异系数（CD）检验,基于耳石形态参数TSL、MW、LDL、WL的CD值均小于1.28,属于种群间差异。中型群与微型群鸢乌贼胴长与耳石主要形态特征的关系大多能较好地以二次函数进行拟合。

We investigated the morphological characteristics,statolith microstructure and population structure of Sthenoeuthis oualaniensis from 455 individuals（ 427 with dorsal photophore and 28 without dorsal photophore） randomly captured in the offshore South China Sea from September to October,2012. As statolith microstructure examined,great lateral dome and wing dome,small dorsal dome and long narrow rostrum dome existed in both two forms. The mantle length（ ML） and total otolith length（ TSL） were in aquadratic function（ P〈0. 05）. Based on dorsal photophore,three populations（ medium-sized population,small-sized population and X3-sized population） could be identified by hierarchica clustering analysis and gray clustering analysis. CD test between medium-sized population and small-sized population shows that the CD record of character TSL,MW,LDL,WL were less than 1. 28,which belonged to interspecies relation. The relationships between ML and all of the statolith variables（ TSL,MW,LDL and WL） in both populationswere best described by quadratic functions.