Data from: Phylogeny of Tetillidae (Porifera, Demospongiae, Spirophorida) based on three molecular markers

Tetillidae are spherical to elliptical cosmopolitan demosponges. The family comprises eight genera: namely, Acanthotetilla Burton, 1959, Amphitethya Lendenfeld, 1907, Cinachyra Sollas, 1886, Cinachyrella Wilson, 1925, Craniella Schmidt, 1870, Fangophilina Schmidt, 1880, Paratetilla Dendy, 1905, and Tetilla Schmidt, 1868. These genera are characterized by few conflicting morphological characters, resulting in an ambiguity of phylogenetic relationships. The phylogeny of tetillid genera was investigated using the cox1, 18S rRNA and 28S rRNA (C1-D2 domains) genes in 88 specimens (8 genera, 28 species). Five clades were identified: (i) Cinachyrella, Paratetilla and Amphitethya species, (ii) Cinachyrella levantinensis, (iii) Tetilla, (iv) Craniella, Cinachyra and Fangophilina and (v) Acanthotetilla. Consequently, the phylogenetic analysis supports the monophyly of Tetilla, a genus lacking any known morphological synapomorphy. Acanthotetilla is also recovered. In contrast, within the first clade, species of the genera Paratetilla and Amphitethya were nested within Cinachyrella. Similarly, within the fourth clade, species of the genera Cinachyra and Fangophilina were nested within Craniella. As previously postulated by taxonomists, the loss of ectodermal specialization (i.e., a cortex) has occurred several times independently. Nevertheless, the presence or absence of a cortex and its features carry a phylogenetic signal. Surprisingly, the common view that assumes close relationships among sponges with porocalices (i.e., surface depressions) is refuted.四轴海绵科（Tetillidae）为呈球形至椭圆形的广布性寻常海绵。该科共包含8个属，分别为：刺四轴海绵属（Acanthotetilla Burton, 1959）、Amphitethya Lendenfeld, 1907、Cinachyra Sollas, 1886、Cinachyrella Wilson, 1925、Craniella Schmidt, 1870、Fangophilina Schmidt, 1880、Paratetilla Dendy, 1905以及Tetilla Schmidt, 1868。这些属仅存在少量相互冲突的形态学特征，却使得其系统发育关系仍存在歧义。 研究人员基于88份标本（涵盖8个属、28个物种）的cox1、18S rRNA以及28S rRNA（C1-D2结构域）基因，对四轴海绵科各属的系统发育关系展开了探究。最终鉴定出5个演化支：① Cinachyrella、Paratetilla与Amphitethya的物种；② Cinachyrella levantinensis；③ Tetilla属物种；④ Craniella、Cinachyra与Fangophilina的物种；⑤ Acanthotetilla属物种。 据此，系统发育分析证实了Tetilla属的单系性——该属目前尚未发现已知的形态共衍征，Acanthotetilla属的单系性同样得到支持。与之相对的是，在第一个演化支中，Paratetilla与Amphitethya的物种嵌套于Cinachyrella属内；类似地，在第四个演化支中，Cinachyra与Fangophilina的物种同样嵌套于Craniella属内。正如分类学家此前所推测的那样，外胚层特化（即皮层）的丢失已独立发生多次。尽管如此，皮层的有无及其形态特征仍携带系统发育信息。令人意外的是，此前认为具有孔杯（即体表凹陷）的海绵类群亲缘关系较近的主流观点被推翻。