Description of two new interstitial species of Psammodrilidae (Annelida) from Bermuda

Abstract

The family Psammodrilidae (Annelida) is a group of small polychaetes hitherto containing three nominal species in Psammodriloides and Psammodrilus. Psammodrilus swedmarki, n. sp. and P. moebjergi, n. sp. are described from subtidal coarse sand in Bermuda. Both new species are interstitial, as is the monotypic Psammodriloides fauveli Swedmark, 1958, which they resemble by their small size and lack of a muscular collar region. However, studies with scanning electron microscopy show that the larger, hermaphroditic P. moebjergi possesses a pair of peristomial dorsolateral non-ciliated areas with hexagonal cells representing those of the characteristic collar region of Psammodrilus. The uncini of both species resemble those of Psammodrilus balanoglossoides Swedmark, 1952. The systematically contradicting characters support a synonymization of the two genera. An emended diagnosis of Psammodrilus and a key to the species are presented.

Keywords:

• Progenesis
• Psammodrilus swedmarki
• P. moebjergi
• synonymy
• 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

Acknowledgments

The Carlsberg Foundation and the Bermuda Zoological Society financially supported the study. This is Contribution #113, Bermuda Biodiversity Project (BBP), Bermuda Aquarium, Natural History Museum and Zoo. Special thanks to Mark Outerbridge, Philippe Rouja and Anson Nash for their kind and supportive assistance with collecting in Bermuda.

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