TABLE 7 in The species diversity and phylogeny of the genus Siphlonurus Eaton, 1868 from China (Ephemeroptera: Siphlonuridae)

TABLE 7. Identification characteristics of male imago (Columns 6–10). CharacterInner margin of basal segment of forcepsLength of penis longer than or subequal to styligerDorsal elongation of penisDorsal sclerotized transverse band of penisShape of penisSpeciesS. chankaewith projectionsubequalcurved, with an enlarged base, and outer margin with about 3 small spines.without expansiontwo penis lobes distinctly separated, inner margin with small spines, and outer margin concaveS. davidiwithout projectionsubequalstraight and spineless, with a sclerotized outer marginwithout expansioneach penis lobe tip with a brown sclerotized plates, length of two penis lobes ca. 1.1x widthS. dongxiwith projectionlongerstraight, spineless, and entirely sclerotizedwithout expansioninner margin of each penis lobe with a brown groove, length of two penis lobes ca..1.2x widthS. immaniswith projectionsubequalslender and spinelesswithout expansiontwo penis lobes separated, inner margin of each penis lobe with spines basally, outer margin concave near the middleS. lacustriswith projectionsubequalshort, sharp and spinelessexpanded in the middleinner margin of each penis lobe with 5–6 long spines, outer margin with approximately four small spines, with a short and wide projectionS. orientaliswithout projectionsubequalstraight and spineless, with a sclerotized outer marginwithout expansioninner margin of each penis lobe with oblique brown sclerotized plates, upper half of penis lobe expanded, length of two penis lobes ca. 1.8x widthS. palaearcticuswith projectionsubequalwide and arched, with a few spines apically (approximately 2–3 spines)without expansioneach penis lobe sclerotized, apex densely covered with spines, an additional long and slender projection between dorsal elongation and each penis lobeS. polyspineuswith projectionlongershort, blunt and spinlessexpanded in the middleinner margin with approximately 12 small spines, outer margin with approximately 7 serrated small spines, each penis lobe with a slender and sharp projectionS. zhelochovtseviwith projectionsubequalarched and distinctly enlarged apically, outer margin with about 8 small spineswithout expansiontwo penis lobes distinctly sclerotized, inner margin of each penis lobe with 6–9 small spines, outer margin concave表7 雄成虫（第6至10列）的鉴定特征。 本次鉴定的特征项依次为：钳突基节内缘、阳茎长度与阳茎基突(Styliger)的比例（长于或等长）、阳茎背侧延伸结构、阳茎背侧硬化横带、阳茎形态。各物种的具体鉴定特征如下： 1. **S. chankaew**：钳突基节内缘具突起；阳茎长度与阳茎基突等长；阳茎背侧延伸呈弯曲状，基部膨大，外缘具约3枚小棘；阳茎背侧硬化横带无膨大；阳茎形态为两叶明显分离，内缘具小棘，外缘凹陷。 2. **S. davidi**：钳突基节内缘无突起；阳茎长度与阳茎基突等长；阳茎背侧延伸直且无棘，外缘硬化；阳茎背侧硬化横带无膨大；阳茎形态为每叶顶端具褐色硬化板，两叶总长约为宽的1.1倍。 3. **S. dongxi**：钳突基节内缘具突起；阳茎长度长于阳茎基突；阳茎背侧延伸直、无棘且完全硬化；阳茎背侧硬化横带无膨大；阳茎形态为每叶内缘具褐色凹槽，两叶总长约为宽的1.2倍。 4. **S. immanis**：钳突基节内缘具突起；阳茎长度与阳茎基突等长；阳茎背侧延伸细长无棘；阳茎背侧硬化横带无膨大；阳茎形态为两叶分离，每叶内缘基部具棘，中部附近外缘凹陷。 5. **S. lacustris**：钳突基节内缘具突起；阳茎长度与阳茎基突等长；阳茎背侧延伸短而尖锐、无棘；阳茎背侧硬化横带中部膨大；阳茎形态为每叶内缘具5~6枚长棘，外缘具约4枚小棘，且具短宽突起。 6. **S. orientalis**：钳突基节内缘无突起；阳茎长度与阳茎基突等长；阳茎背侧延伸直且无棘，外缘硬化；阳茎背侧硬化横带无膨大；阳茎形态为每叶内缘具斜生褐色硬化板，叶上半部膨大，两叶总长约为宽的1.8倍。 7. **S. palaearcticus**：钳突基节内缘具突起；阳茎长度与阳茎基突等长；阳茎背侧延伸宽而拱曲，顶端具约2~3枚棘；阳茎背侧硬化横带无膨大；阳茎形态为每叶硬化，顶端密被棘，背侧延伸部与每叶间具1枚细长突起。 8. **S. polyspineus**：钳突基节内缘具突起；阳茎长度长于阳茎基突；阳茎背侧延伸短而钝、无棘；阳茎背侧硬化横带中部膨大；阳茎形态为内缘具约12枚小棘，外缘具约7枚锯齿状小棘，每叶具1枚细长尖锐突起。 9. **S. zhelochovtsevi**：钳突基节内缘具突起；阳茎长度与阳茎基突等长；阳茎背侧延伸拱曲且顶端明显膨大，外缘具约8枚小棘；阳茎背侧硬化横带无膨大；阳茎形态为两叶明显硬化，每叶内缘具6~9枚小棘，外缘凹陷。