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.

Tetillidae科（Tetillidae）为世界性分布的球形至椭圆形寻常海绵。该科共计包含8个属，分别为：棘四海绵属（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。上述各属的形态学性状冲突较少，导致其系统发育关系存在歧义。研究人员基于88份标本（隶属于8个属、28个种）的cox1、18S核糖体RNA（18S rRNA）及28S核糖体RNA（28S rRNA，C1-D2结构域）基因，对Tetillidae科各属的系统发育关系展开了解析。研究共识别出5个演化支：（i）Cinachyrella、Paratetilla及Amphitethya物种类群；（ii）Cinachyrella levantinensis类群；（iii）Tetilla类群；（iv）Craniella、Cinachyra及Fangophilina类群；（v）Acanthotetilla类群。综上，系统发育分析支持Tetilla属为单系群，该属目前尚无已知的形态共源性状。Acanthotetilla属的单系性也得到了支持。与之相对，在第一类演化支中，Paratetilla属与Amphitethya属的物种均嵌套于Cinachyrella属内。同样地，在第四类演化支中，Cinachyra属与Fangophilina属的物种均嵌套于Craniella属内。正如分类学家此前所提出的，外胚层特化（即皮层）的丢失已独立发生多次。尽管如此，皮层的有无及其特征仍携带系统发育信号。令人意外的是，认为具孔杯（即体表凹陷）的海绵间亲缘关系紧密的主流观点被推翻了。