Roberto-DA-Silva Lúcio, França Marco A G, Cabreira Sérgio F, Müller Rodrigo T, Dias-DA-Silva Sérgio
Programa de Pós-Graduação em Biodiversidade Animal, Universidade Federal de , Av. Roraima, 1000, Bairro Camobi, 97105-900 Santa Maria, RS, Brasil.
Laboratório de Paleontologia, Universidade Luterana do Brasil, Av. Farroupilha, 8001, Bairro São José, 92425-900 Canoas, RS, Brasil.
An Acad Bras Cienc. 2016 Sep;88(3):1309-23. doi: 10.1590/0001-3765201620150456. Epub 2016 Aug 4.
Many authors have discussed the subnarial foramen in Archosauriformes. Here presence among Archosauriformes, shape, and position of this structure is reported and its phylogenetic importance is investigated. Based on distribution and the phylogenetic tree, it probably arose independently in Erythrosuchus, Herrerasaurus, and Paracrocodylomorpha. In Paracrocodylomorpha the subnarial foramen is oval-shaped, placed in the middle height of the main body of the maxilla, and does not reach the height of ascending process. In basal loricatans from South America (Prestosuchus chiniquensis and Saurosuchus galilei) the subnarial foramen is 'drop-like' shaped, the subnarial foramen is located above the middle height of the main body of the maxilla, reaching the height of ascending process, a condition also present in Herrerasaurus ischigualastensis. These results suggest that this structure might be phylogenetically important and further investigation with a large set of valid taxa is necessary to properly evaluate its importance among Archosauria.
许多作者都讨论过主龙形类中的鼻下孔。在此，我们报告了主龙形类中该结构的存在情况、形状和位置，并研究了其系统发育重要性。根据分布情况和系统发育树，它可能在引鳄、黑瑞拉龙和副鳄形类中独立出现。在副鳄形类中，鼻下孔呈椭圆形，位于上颌主体的中部高度，未达到上升突的高度。在来自南美洲的基础坚蜥类（钦氏普雷托鳄和加氏蜥鳄）中，鼻下孔呈“水滴状”，位于上颌主体中部高度之上，达到上升突的高度，这种情况在伊斯基瓜拉斯托黑瑞拉龙中也存在。这些结果表明，该结构可能在系统发育上具有重要意义，有必要对大量有效分类单元进行进一步研究，以正确评估其在主龙类中的重要性。
