A DNA-based description of a new nemertean (phylum Nemertea) species

Abstract

Nemerteans (Nemertea) are traditionally described from internal characters obtained from histological sections of serially sectioned animals. The procedure is time-consuming and requires careful preparation of specimens. The preparations often suffer from artefacts caused by the handling of the animals, since they contract extensively when fixed. It is commonly stated that nemerteans can only be reliably identified using internal characters and the taxon is therefore viewed as ‘difficult’ and, as such, often overlooked in e.g. marine inventories because nobody has the time, facilities or skills to do the sectioning. Contrary to this often-stated ‘fact’, our experience is that many nemerteans can be identified from external characters, although there of course are exceptions. The risk for fixation artefacts in combination with an ascertained high (natural?) intraspecific morphological variation make us pose the question whether anatomy is in fact the best and most efficient basis for phylogeny and classification. There is undoubtedly a large number of undescribed/unnamed nemerteans. To cope with this, we pragmatically propose that nemerteans can be described by a combination of external characters and DNA sequences. We apply this concept on one recently found species new to science, Pseudomicrura afzelii gen. et sp. nov.

Keywords:

• Description
• DNA
• nemertea
• taxonomy

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark