Nemertean taxonomy - Implementing changes in the higher ranks, dismissing Anopla and Enopla

Strand, Malin ... et al.-- 2 pagesNemertean classification has closely followed Stiasny‐Wijnhoff's scheme (1936) that was based on Schultze's (1851) division of the taxon into the two classes Anopla and Enopla. In August 2018, the 9th International Conference of Nemertean Biology took place in the Wadden Sea Station of the Alfred Wegener Institute in List auf Sylt, Germany. At this meeting, the community reached consensus to revise nemertean taxonomy at the class level, based on the compiled evidence from studies on nemertean systematics published in the last 15 years (Andrade et al., 2012, 2014 ; Thollesson & Norenburg, 2003). Previous classifications (e.g., Stiasny‐Wijnhoff, 1936) are not based on phylogenetic grounds, and the use of these names is therefore nowadays not wholly informative. With the purpose of facilitating the practical use of the nemertean taxonomy and also making nemertean taxonomy reflect a wealth of more recent information, we conclude that the ranks Anopla and Enopla should be eliminated with the following argumentation: “Enopla” has for long held no more information than the name “Hoplonemertea”. “Anopla” is paraphyletic and the name usually corresponds to the following traits: (a) not bearing stylet; and (b) mouth and proboscis having separate openings. This information is equally well presented in a system that also bears information on natural groups. The names “Anopla” and “Enopla” are hence dismissed and the following system of the Nemertea phylum is implemented: Class: Palaeonemertea Currently no Orders Class: Pilidiophora Order: Heteronemertea Class: Hoplonemertea Order: Monostilifera Order: Polystilifera The changes do not affect lower levels of taxonomy, but in accordance with Thollesson and Norenburg (2003), who first presented Pilidiophora, genus Hubrechtella is transferred from class Palaeonemertea to the class PilidiophoraPeer Reviewe