Primnoidae (Cnidaria: Octocorallia: Calcaxonia) of the Okeanos Explorer expeditions (CAPSTONE) to the central Pacific 

Abstract

This paper discusses and illustrates the 23 primnoid species collected by the R/V Okeanos Explorer in the US marine protected areas in the central and western Pacific, ranging from the Musician Seamounts in the north to American Samoa to the south, and the northern Mariana Islands to the west (CAPSTONE expeditions, 2015-2017). In situ photographs are provided for most species. Thirteen of the 23 species are described as new, as well as two new genera. One new genus, Macroprimnoa, possesses some of the largest polyps in the family. A dichotomous key is provided to facilitate comparisons among the 27 species of Calyptrophora. An update of the abyssal octocorallian species occurring deeper than 3000 m is provided, increasing that number from 39 to 49 species. The character of the articulating ridge, found on the distal edge of the basal body wall scales, is re-evaluated, resulting in four genera having this character state, and requiring the description of the new genus Pseudonarella.

The Unknown and the Unexplored: Insights Into the Pacific Deep-Sea Following NOAA CAPSTONE Expeditions

“…Several new genera and new species were observed and collected during CAPSTONE, including a previously undescribed genus and species of sea star (family Goniasteridae, class Asteroidea) discovered in the Musicians Seamounts in 2017 (Figure 7). CAPSTONE data have already been instrumental in the description of 13 new species and two new genera of Primnoid corals (Cairns, 2018), as well as a new species of stylasterid coral, Crypthelia kelleyi from the Northwest Hawaiian Islands (Cairns, 2017). One new genus, Macroprimnoa spp., possesses some of the largest polyps in the family (Cairns, 2018).…”

“…CAPSTONE data have already been instrumental in the description of 13 new species and two new genera of Primnoid corals (Cairns, 2018), as well as a new species of stylasterid coral, Crypthelia kelleyi from the Northwest Hawaiian Islands (Cairns, 2017). One new genus, Macroprimnoa spp., possesses some of the largest polyps in the family (Cairns, 2018). A likely novel species of Neopilina monoplacophoran was observed in American Samoa, which expands the known diversity of living monoplacophorans (Sigwart et al, 2018), which were previously known from the fossil record but only discovered to be extant in 1952 (Lemche, 1957).…”

Oceanographic Drivers of Deep-Sea Coral Species Distribution and Community Assembly on Seamounts, Islands, Atolls, and Reefs Within the Phoenix Islands Protected Area

“…comm.). N. compressa was observed and collected within PIPA at Carondelet Reef and Maibua Seamount between 373 and 583 m. One colony of Thouarella tydemani Versluys, 1906, a relatively rare species in that genus originally reported from Indonesia at 520 m, was only observed 33 times and sampled at Winslow Reef at 801 m. The sea fan, Paracalyptrophora hawaiiensis Cairns, 2009, was reported from the Phoenix Islands Protected Area between 445 and 666 m. Along with new records from Tokelau (Pao Pao Seamount), American Samoa, and Rawaki Island, this suggests P. hawaiiensis has a wider distribution throughout the southwest Pacific and north to Hawaii at upper bathyal depths (Cairns, 2018). Calyptrophora clarki Bayer, 1951 was observed 48 times and sampled 3 times between 418 and 1211 m in PIPA.…”

“…In the genus Narella, two new species were described with material from sites within the Phoenix Islands. The type specimen of Narella fordi Cairns (2018) was identified from Te Kaitira Seamount at 1899 m. This species was only been observed at Te Kaitira Seamount between the depths of 1817 and 1932 m. Narella aurantiaca Cairns (2018) was identified off Nikumaroro at 1112 m but also observed at McKean Island and Winslow Reef between 558 and 1105 m. This species was also encountered in the Musicians Seamounts and off Wake Island at similar depths (Cairns, 2018). Narella compressa Kinoshita, 1908, was identified off Carondelet Reef at 497 m and is likely the first record since its encounter in 1906 off Japan (Cairns, pers.…”

“…Voucher samples were examined alongside records of visual observations to better understand the distribution of these species in their known localities ( Supplementary Table S1). Recently, octocorals in the family Primnoidae have been relatively well-studied in the Pacific compared to other octocoral taxa, thus the majority of the new species encountered occur in that group (Cairns, 2018). In the genus Narella, two new species were described with material from sites within the Phoenix Islands.…”