摘要
为了给头足类的分类提供更多依据,本文采用扫描电镜技术对枪鱿科和蛸科各3种头足类的齿舌进行了显微观察和比较研究。研究显示：6种头足类的齿舌均由7列纵向齿组成,齿式为3·1·3。枪鱿科的3个种（杜氏枪鱿（Uroteuthis duvaucelii）、苏门答腊枪鱿（Loliolus sumatrensis）、莱氏拟乌贼（Sepioteuthis lessoniana））,中央齿1列,具有3个齿尖;侧齿位于中央齿两侧各3列,向外分别称为第一侧齿、第二侧齿和第三侧齿,也称为侧齿、内缘齿和外缘齿;缘板不发达。蛸科的3个种（卵蛸（Amphioctopus ovulum）、台湾小孔蛸（Cistopus taiwanicus）、Octopus sp.）,中央齿1列,具有3~5个齿尖,侧齿各3列,缘板发达。结果表明,不同种的头足类动物,其齿舌形态差别较大,可作为分类依据对中国沿海分布的物种进行鉴定。
Morphometric characteristics of groups are used widely to identify cephalopod species.However,some morphometric characteristics are usually affected by the factors such as environmental conditions.Hard structure of cephalopods may be more effective as a discriminatory tool for analyzing variation and identification.As a digestive organ and one of the hard structures,the characteristics and arrangement pattern of radulae of cephalopods vary within species but keep consistent among populations.For this reason,it will be used to identify cephalopod species in this study.This study is based on scanning electron microscopic observation and morphological measurements of six cephalopods,which were collected from Chinese waters.Radulae were firstly obtained with forceps and washed by distilled water to flush away adhesive materials,then immersed in 5%~10% NaOH and boiled in distilled water.Radulae samples were CO2 critical point dried,then,coated with gold and finally observed under JSM-840 scanning electron microscope.The results show that all the radulae consist of 7longitudinal rows of teeth：a median tooth and the 1st,2nd and 3rdlateral or lateral,inner marginal and outer marginal teeth.The radula formula is 3·1·3.According to the morphological characteristics and arrangement pattern,such as numbers of cusps,shape of marginal plate,loliginids are quite easy to be identified from octopods.Loliginids（Uroteuthis duvaucelii,Loliolus sumatrensis,Sepioteuthis lessoniana）have 3cusps in the median tooth,and its marginal plate is less developed,which shapes like ellipse.Proportional value of width of the 2nd lateral teeth to median teeth in the three loliginids is quite different,around 0.5,1.5and 1.0,respectively,making it apparent feature to compare.The octopods（Amphioctopus ovulum,Cistopus taiwanicus,Octopus sp.）have 3to 5cusps in the median tooth and the marginal plate is developed well,which shapes like rectangle.Cusps numbers and arrangements of the median tooth vary in the three octopod species,making them easily identified.The results also indicate that radula structure varies a lot among different species,and it should be thought in the cephalopods taxonomy.Radula is a peculiar digestive organ in Mollusca,which serves for grinding food bitten off from the beak and transferring them into the pharynx.The median teeth of octopods have 3to 5sharp cusps,working with the 2nd lateral teeth to grind food;the 1st lateral teeth are smaller,mainly transferring food pieces,but also grinding them.The median teeth and 1st lateral teeth of loliginids have 3cusps each,serving as grinding food,and the 2nd and 3rd lateral teeth help to prevent food piece from slipping.Different morphological characteristics of radulae will develop a better understanding of food habit of cephalopods.
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第5期32-37,共6页
Periodical of Ocean University of China
基金
国家自然科学基金项目(31172058)
中央高校基本科研业务费专项项目(201362022)资助~~
关键词
头足纲
枪鱿科
蛸科
齿舌
扫描电镜
形态学
Cephalopoda
Loliginidae
Octopodidae
radula
scanning electron microscope
morphology
