Tedania Gray 1867

The genus Tedania

This genus is characterized by the morphology of its ectosomal and choanosomal spicules, and the possession of onychaetes as microscleres (Van soest 2017). These microscleres are diagnostic characters for the family Tedaniidae (Van Soest 2002). However, the presence of onychaetes, or onychaete-like microscleres such as oxychaetes has been reported for some species belonging to different families in the Poecilosclerida: Phelloderma (Phellodermidae) (Göcke et al. 2016), Celtodoryx (Coelosphaeridae) (Perez et al. 2006) and Strongylacidon (Chondropsidae) (Menegola et al. 2012). Molecular studies retrieved Tedania species inside the Poecilosclerida clade, even though they lack chelae microscleres, characteristic of many Poecilosclerid families (Morrow et al. 2013). Bergquist and Fromont (1988) considered as valid the genera Tedania (with ectosomal diactinal spicules and choanosomal mon- or diactinal spicules) and Tedaniopsis (with ectosomal and choanosomal diactinal spicules). Van Soest (2002) created a subgeneric classification of Tedania and considered valid three subgenera: Tedania, Tedaniopsis and Trachytedania (Figure 6). According to Van Soest (2002) species with ectosomal diactinal spicules with microspined heads should be allocated in the subgenus Tedania, but there are some species bearing ectosomal diactinal spicules with smooth heads assigned to this subgenus (Tables 3 and 4) (Van Soest et al. 2017). Furthermore, Van Soest (2002) suggested that species with ectosomal diactinal spicules bearing smooth heads should be assigned either to subgenus Tedaniopsis or subgenus Trachytedania, depending on the length of their choanosomal megascleres (Tables 5 and 6). Currently, Trachytedania is considered a valid genus (Van Soest et al. 2017) and is characterized by species having acanthostyles as choanosomal megascleres (Cristobo and Urgorri 2001). All the Tedania and Trachytedania species have ectosomal diactinal spicules: tylotes with microspined heads, tylotes with smooth heads and tornotes (excluding the monotypic species of Tedania (Stylotedania)) (see Tables 3–6) and choanosomal monactinal (styles or acanthostyles) or diactinal spicules (tylotes, oxeas or strongyles). Recently, the monotypic subgenus Stylotedania Van Soest 2017; was erected with monactinal ectosomal and choanosomal spicules (Van Soest 2017). These diagnostic features are different from all the current species assigned to the genera Tedania and Trachytedania (Figure 1).