德永雕翅摇蚊Glyptotendipes tokunagai幼虫龄期及DNA条形码研究*
Research on the larval age and DNA barcoding of Glyptotendipes tokunagai
雷 琦** 刘邦淼 魏相成 刘泽远 党 昊 杨铁柱 郭旭升 王俊如***
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DOI：10.7679/j.issn.20951353.2026.112
作者单位：信阳农林学院水产学院，信阳 464000
中文关键词：德永雕翅摇蚊；幼虫龄期划分；形态测量；DNA条形码；COⅠ基因；遗传距离
英文关键词：Glyptotendipes tokunagai; larval instar division; morphometry; DNA barcoding; COⅠgene; genetic distance
中文摘要：【目的】 明确德永雕翅摇蚊Glyptotendipes tokunagai幼虫的龄期划分与最佳分龄形态指标，并探究不同地理种群的DNA条形码差异。【方法】 通过室内饲养幼虫，测量10项骨化形态指标（头壳长、颏中齿顶端至冠突前缘间距离、头颏宽、颏宽、颏中齿宽、触角长、触角基节长、上颚长、腹颏板长和腹颏板宽），结合频次分布、Brooks/Crosby指数及回归分析进行龄期划分；提取COⅠ基因并测序，利用MEGA 7.0分析序列组成、遗传距离及构建系统发育树。【结果】 德永雕翅摇蚊幼虫具有4个龄期。其中，颏宽（Y4）的三次回归拟合度最高（R2=0.997 0），并且Crosby指数与变异系数符合生长定律，确定颏宽为最佳分龄指标；触角长（Y6）、上颚长（Y8）、腹颏板长（Y9）3项指标可作为辅助指标，推测德永雕翅摇蚊1-4龄幼虫的持续时间分别约为2、3、6和8 d。DNA条形码研究显示德永雕翅摇蚊COⅠ序列具有明显的AT偏好性（A+T含量为63.75%）。系统发育树将种群分为两支：中国种群单独构成一支，与日本、韩国种群的平均遗传距离分别为8.31%和8.70%；日本与韩国种群聚为另一支，两者间遗传距离仅为1.14%。【结论】 德永雕翅摇蚊幼虫有4个龄期，颏宽是可靠的分龄指标，幼虫期为19 d。中国与日本、韩国种群间可能存在隐种。
英文摘要：[Aim] To determine the optimal morphological indicators for identifying the instars of Glyptotendipes tokunagai larvae, and to explore DNA barcoding differences among different geographic populations. [Methods] Larvae were reared in the laboratory, and ten sclerotized morphological characteristics (head capsule length, length from tip of the median teeth of the mentum to the leading coronoid, head mentum width, mentum width, width of the median mentum tooth, antenna length, length of antennal basal segment, mandible length, ventromental plate length and ventromental plate width) were measured. Instar classification was based on the frequency distributions of these variables, the Brooks/Crosby index and regression analysis. The COⅠgene was extracted and sequenced, and MEGA 7.0 was used to analyze sequence composition, genetic distances and to construct a phylogenetic tree. [Results] The results confirm that G. tokunagai larvae have four instars. Among the measured characteristics, mentum width (Y4) had the best fit to the cubic regression model (R2 = 0.997 0). Both the Crosby index and coefficient of variation conformed to Dyar’s law, confirming mentum width as the optimal characteristic for instar identification. Three additional characteristics, namely antenna length (Y6), mandible length (Y8) and ventromental plate length (Y9), can serve as auxiliary indicators. The estimated durations for 1st to 4th instar larvae were approximately 2, 3, 6 and 8 days, respectively. COⅠsequences had a distinct AT bias (A+T content: 63.75%). The phylogenetic tree divided populations into two clades; one comprised of the Chinese population and another comprised of the Japanese and Korean populations. The average genetic distances between the Chinese population and the Japanese and Korean populations were 8.31% and 8.70%, respectively. The genetic distance between the Japanese and Korean populations was only 1.14%. [Conclusion] G. tokunagai larvae have four instars, and mentum width is the most reliable indicator for instar identification. The larval period is estimated to be 19 days. Cryptic species may exist among populations of this species in China, Japan and Korea.