ABSTRACT
Sea pens (Octocorallia: Pennatulacea) constitute one of the most important structural species in soft bottom benthic communities. Most pennatulacean species are deep-water organisms inhabiting depths from 200–6000 m. Among these deep-sea pens, a representative set of colonies from the northeastern Atlantic Anthoptilum murrayi Kölliker, 1880 was collected thanks to the BIOICE research surveys. In this study, 18 colonies of A. murrayi were used to acquire information on essential biological traits such as age and growth rates. Our results showed that the colonies collected ranged between 6–17 years, with a diametric growth rate between 0.10–0.17 mm year−1 and a linear growth rate between 14.97–15.75 mm year−1. Moreover, the number and diameter of oocytes per polyp (PRF, ERF), and the reproductive effort at the colony level (PRE, ERE) were determined. These values were compared between colonies of different sizes and within each colony. The largest observed diameter was 1179 μm for oocytes and 711.3 μm for spermatocysts. Both approaches (growth and reproduction) were correlated, indicating that a given large A. murrayi colony (∼300 mm) might be ∼17 years old and contain >7000 oocytes, from which possibly about 2000 oocytes (∼27%) would be spawned per year.
Acknowledgements
We would like to thank numerous colleagues who have worked on the campaigns during the BIOICE research surveys from which the material examined here was obtained. On these cruises, our special thanks are addressed to Gudmundur Gudmundsson, Gudmundur Vidir, Jörundur Svavarsson (BIOICE programme). The authors would also like to thank Juan M. Muñoz Pichardo (Department of Statistics and Operations Research, University of Seville) for his appreciated help in the statistical analyses using the SPSS software. The authors are also grateful for the criticisms and suggestions provided by two anonymous referees and the editor of MBR. Mr Tony Krupa is thanked for reviewing the English version.
Disclosure statement
No potential conflict of interest was reported by the authors.