The use of more than one nomenclatural code is becoming increasingly common in some biological sub-disciplines. To minimize nomenclatural instability, we have decided to establish a higher level systematization for Thalattosuchia under both the International Code of Phylogenetic Nomenclature (‘PhyloCode’) and the International Code of Zoological Nomenclature (‘Zoological Code’). We undertook a series of phylogenetic analyses with an expanded dataset to examine the origins of Thalattosuchia within Crocodylomorpha, and determined the clade’s diagnostic characters. Based on these analyses, we provide updated diagnoses for Thalattosuchia and its subclades under both the PhyloCode and Zoological Code. We also introduce two new nomina that are regulated under the PhyloCode (Neothalattosuchia and Euthalattosuchia), and the nomen Dakosaurina, which is registered under both nomenclatural codes. Moreover, we introduce PhyloCode-compliant phylogenetic definitions for Thalattosuchia and its subclades. As we cannot reliably discriminate between the positional hypotheses for Thalattosuchia within Crocodylomorpha, the clades’ origins are as much of a mystery today as they were over a century ago. However, we hope that using the same diagnostic characters to define the same clades, with the same nomina, under both nomenclatural codes will be an example to others to follow.

中文翻译：

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海鳄亚目（原龙目：鳄形目）的历史、系统学和命名法

在一些生物学子学科中，使用多种命名代码变得越来越普遍。为了尽量减少命名的不稳定性，我们决定根据国际系统发育命名法典（“PhyloCode”）和国际动物学命名法典（“Zoological Code”）为海鳄亚目建立更高级别的系统化。我们利用扩展的数据集进行了一系列系统发育分析，以研究鳄形目中海鳄亚目的起源，并确定该分支的诊断特征。基于这些分析，我们根据系统代码和动物学代码提供海鳄亚目及其分支的最新诊断。我们还引入了受 PhyloCode 监管的两个新命名（Neothalattosuchia 和 Euthalattosuchia），以及在两个命名法下注册的命名 Dakosaurina。此外，我们还介绍了海鳄亚目及其分支的符合 PhyloCode 的系统发育定义。由于我们无法可靠地区分海鳄亚目在鳄形目中的位置假说，因此这些分支的起源在今天和一个多世纪前一样是一个谜。然而，我们希望在两种命名法代码下使用相同的诊断特征来定义相同的进化枝，具有相同的命名，这将成为其他人效仿的例子。