Nemertean Larval ID

A guide to planktonic nemertean larvae from the northeast Pacific

Identify nemertean larvae by:

This is an identification guide for nemertean larvae in the NE Pacific. I generated this guide as part of my PhD research at the University of Oregon's marine lab – the Oregon Institute of Marine Biology. Please use the categories at left to get started identifying your larva!

All images and data shown were generated by the authors and can be used, with appropriate citation, for education purposes only.

Project summary

We connected the larval and adult forms of 36 nemertean species using qualitative planktonic and benthic surveys.  Prior to this work, only the larva of one northeast Pacific nemertean species could be identified with morphological characters.  We identified larvae using a multifaceted approach including traditional embryology and DNA sequence data from barcoding gene regions 16S and COI. Here, we provide the first identification key for nemertean larvae.  We not only reveal the identity of larvae from species previously known to the northeast Pacific, we also report the presence of larvae belonging to species previously only known from the northwest Pacific, including Hubrechtella juliae and Carinoma hamanako.  Our attempts to identify planktonic larvae also uncovered new and undescribed nemertean species.  Some of this new diversity is represented by both adult and larval faunas, while other species are currently represented by larvae alone.  Nineteen species are what we refer to as “orphan larvae”, representing species that we currently only find as larvae in the plankton and have yet to find in their adult form.  This identification guide comprises a key, images, short morphological descriptions, and DNA sequence data for all species encountered as larvae. 

how to use this guide

Don't forget about the other larvae!

Although the focus of our research is the phylum Nemertea, we are often interested in projects relating to other marine phyla.  Be sure to check out our non-nemertean larval projects including the identification of deep sea seep species and northeast Pacific coastal species!