Ernstia adusta, Worheide and Hooper, 1999

Voigt, Oliver & Wörheide, Gert, 2016, A short LSU rRNA fragment as a standard marker for integrative taxonomy in calcareous sponges (Porifera: Calcarea), Organisms Diversity & Evolution (New York, N. Y.) 16 (1), pp. 53-64 : 61

‘Clathrina’ adusta is not a member of the genus Ernstia

Klautau and co-workers assigned the species ‘Clathrina’ adusta Wörheide and Hooper (1999) to their new genus Ernstia ( Klautau et al. 2013) without consideration of molecular data. We find that this decision is in conflict with their genus definition, where Ernstia is described to have tetractines as the ‘most abundant spicules or occur at least in the same proportion as the triactines.’ In contrast, Wörheide and Hooper (1999) describe the skeleton of the species’ skeleton as follows: ‘The major part of the skeleton consists of regular triactines with more-or-less cylindrical actines, […]. A few tetractines are present, more abundant in the walls of the larger tubes.’ The assignment of C. adusta to Ernstia ( Klautau et al. 2013) was therefore not justified, and C. adusta would have better fitted in one of the newly described genera Arthuria or Brattegardia , which are among other traits diagnosed by possessing tri- and tetractines, where the former are more abundant ( Klautau et al. 2013). From our phylogeny, C. adusta is clearly not close to the so far only recognized species of the genus Brattegardia (Clathrina) nanseni . Unfortunately, no certainly determined member of Arthuria is included in our phylogeny, and the phylogenetic affinities cannot be falsified. We nonetheless suggest transferring ‘Clathrina’ adusta to the genus Arthuria (Clathrina) adusta , based upon the morphological data and the phylogenetic position in respect to Brattegardia .