The Global Diversity of Sea Pens (Cnidaria: Octocorallia: Pennatulacea)

Abstract

Recent advances in deep-sea exploration technology coupled with an increase in worldwide biotic surveys, biological research, and underwater photography in shallow water marine regions such as coral reefs, has allowed for a relatively rapid expansion of our knowledge in the global diversity of many groups of marine organisms. This paper is part of the PLoS ONE review collection of WoRMS (the Worldwide Register of Marine Species), on the global diversity of marine species, and treats the pennatulacean octocorals, a group of cnidarians commonly referred to as sea pens or sea feathers. This also includes sea pansies, some sea whips, and various vermiform taxa. Pennatulaceans are a morphologically diverse group with an estimated 200 or more valid species, displaying worldwide geographic and bathymetric distributions from polar seas to the equatorial tropics and from intertidal flats to over 6100 m in depth. The paper treats new discoveries and taxa new to science, and provides greater resolution in geographic and bathymetric distributions data than was previously known, as well as descriptions of life appearances in life and in situ observations at diverse depth.

Revision and redescription of the species previously included in the genus <i>Amphilaphis</i> Studer and Wright in Studer, 1887 (Octocorallia: Primnoidae)

“…The new species Thouarella vitjaz enlarges the geographical and bathymetrical distribution of the family Primnoidae at 6400 m depth, being the deepest known primnoid and octocoral, exceeding the deepest pennatulacean Umbellula found at 6100 m depth (Williams 1995(Williams , 2011. Though the species here reported have been included in different genera, they had already been included in this family.…”

Cold-Water Coral Habitats in Submarine Canyons of the Bay of Biscay

“…Antipatharians and seapens can occur much deeper, even greater than 6,000 m (Williams, 2011;Wagner et al, 2012). The occurrence, abundance and diversity of CWC species and/or habitat were influenced by temperature, salinity, water density, currents and trophic input (e.g., Roberts et al, 2006;Dullo et al, 2008;Yesson et al, 2012, in press;Mohn et al, 2014;Robert et al, 2015).…”

Sea pen (Pennatulacea) aggregations on the northern Spanish shelf: distribution and faunal assemblages

“…The few aggregations of P. spinosum and V. cynomorium were found at about 50 m depth, although some specimens were recorded at unusual depths in the area if compared with data in the literature (Supplementary Material Table S1). We found that 70% of the occurrences of V. cynomorium in our study area were detected above 100 m and three colonies were even found at an unusual depth of 372 m, despite the fact that these two species are known to be continental-shelf species with a distribution related to terrigenous sediments (Gili and Pagès 1987, Williams 2011, Sardá et al 2012. López-González et al (2001) reported, in the eastern Atlantic, a wider depth range (25-188 m) than Williams (1990, 13-91 m), and Gili and Pagès (1987) showed an even deeper limit in the Mediterranean Sea (around 260 m).…”

“…The genus Pennatula has a worldwide distribution (Williams 2011), and three out of the five species listed by Williams (2014) from the European Register of Marine Species area occur in the Cantabrian Sea off Spain: namely P. aculeata, P. grandis and P. phosphorea. Records of P. rubra from this area are misidentifications.…”

“…The two genera Pteroeides and Veretillum are reported in the eastern Atlantic and West Pacific and described to be bathymetrically restricted to shallow waters (Williams 2011). Specifically, the geographical distribution of P. spinosum and V. cynomorium ranges from the Bay of Biscay to the Atlantic shores of Africa, including the Mediterranean Sea (Gili and Pagès 1987, López-González et al 2001, Altuna, 2010.…”