Table 1 in Descriptions And Recognition Of Larvae Of Some Northern North American Species Of Ilybius Erichson (Coleoptera: Dytiscidae)

Table 1. Diagnostic characters for distinguishing between larvae of the genera Ilybius Erichson and Agabus Leach as given by Galewski (1987) and Nilsson (1987). CharacterAgabusIlybius1. Last abdominal segment (RespiratoryShort or TruncateElongateSiphon)2. Position of dorsal setae of fore femora½ or <½ the length3 ⁄ or ⅔ the length 53. Abdominal segment VI membranousNarrowWidesternum表1 依据Galewski（1987）与Nilsson（1987）的研究成果，区分狭龙虱属（Ilybius Erichson）和丽龙虱属（Agabus Leach）幼虫的分类鉴别特征： | 序号 | 鉴别特征 | 丽龙虱属（Agabus Leach） | 狭龙虱属（Ilybius Erichson） | | :---: | :---: | :---: | :---: | | 1 | 最后腹节（呼吸管） | 短截形 | 细长形 | | 2 | 前足股节背刚毛着生位置 | 长度的½或小于½ | 长度的⅔ | | 3 | 第六腹节膜质区 | 狭窄 | 宽阔 |