A taxonomic review study on the apparatuses of the lower-middle Darriwilian index conodonts, based on the collections from the Precordillera and those described and illustrated in worldwide literature, had led to a new interpretation of the Lenodus apparatus composition. This apparatus is composed of pectiniform elements without mirror symmetry (Pa and Pb elements) with pastiniscaphate morphology and sometimes showing a micropattern structure (honeycomb) on the platform surface. The transitional series of S elements present the elements alate Sa, tertiopedate Sb, bipennate Sc, and quadriramate Sd with wartlike extensions on the tip of the cusps, and the M elements have a modified “geniculate” morphology. The analysis of the apparatuses of the Darriwilian index conodonts allows us to interpret that the genus Lenodus includes the following species: Lenodus variabilis, Lenodus crassus, Lenodus pseudoplanus, and Lenodus suecicus. This proposal is supported by the apparatus architecture, the transitional morphological features of the P elements, and the micropattern structure on the P and S elements present in all these species.

对下中达利维亚指数牙形石设备的分类学评论研究，是基于Precordillera的收集物以及全球文献中描述和说明的收集物，从而对Lenodus的仪器组成有了新的解释。该装置由无镜面对称的果胶状元素（Pa和Pb元素）组成，具有鱼鳞状的形态，有时在平台表面显示微图案结构（蜂窝状）。S元素的过渡系列表示元素Sa，叔脚形Sb，二萜形Sc和四边形Sd，在尖尖上有疣状延伸，M元素具有改良的“膝状”形态。对Darriwilian指数牙形石的仪器的分析使我们能够解释该属Lenodus包括下列物种：Lenodus变异，Lenodus克拉苏，Lenodus pseudoplanus，和Lenodus suecicus。装置结构，P元素的过渡形态特征以及所有这些物种中存在的P和S元素上的微图案结构，为该建议提供了支持。