Revised nomenclature of the sea pen genus Balticina Gray, 1870 (= Halipteris Kölliker, 1870) (Anthozoa: Octocorallia).

The pennatulacean genus Balticina has had a long and confusing taxonomic history, with serious nomenclatural problems that remain unresolved. Owing to disagreements about authorships and dates of publication, the names Pavonaria, Norticina and Halipteris have all been used as valid in place of Balticina, or else been regarded as its junior synonyms, even simultaneously. In this paper, after an extensive literature review, we determine the authorships and dates for all the taxa involved in accordance with the provisions of the International Code of Zoological Nomenclature and establish Balticina Gray, 1870 (=Halipteris) and Balticinidae Balss, 1910 (=Halipteridae) as the valid genus and family names, respectively, for this group of sea pens. We also propose the replacement name Rakollikeria for the preoccupied genus name Pavonaria Kölliker, 1870 (Balticinidae) (nec Schweigger, 1819 - Funiculinidae).

The deep-sea pennatulacean genus Porcupinella - with the description of a new species from Tasmania (Anthozoa, Octocorallia, Chunellidae).

The recently described deep-sea pennatulacean genus Porcupinella was previously known only by the type species, Porcupinella profunda from the equatorial eastern Atlantic to the eastern North Atlantic Ocean. New data is provided on morphology, distribution, bathymetry, and related taxa. A second species is added here as well - a new species is described from the Tasman Sea in the southwestern Pacific. The new species, Porcupinella tasmanica, is distinguished from P. profunda by its distinctive hook-shaped growth form, laterally compressed dorsal keel, and differing regions that are occupied by siphonozooids. A key to the species of the deep-sea pennatulacean family Chunellidae is included based on comparative morphology.

A new genus and species of enigmatic gorgonian coral from the Ryukyu Archipelago, northwestern Pacific, with a discussion of calcaxonian systematics (Cnidaria, Anthozoa, Octocorallia).

A new genus and species of flagelliform gorgonian coral is described from mesophotic depth in the western Pacific Ocean. The new taxon exhibits calcaxonian morphological characters and shares affinities to both the clade that includes the Chrysogorgiidae, Primnoidae, and Isididae, as well as the clade that includes the Ellisellidae and the Pennatulacea. Based on morphology alone, placement in a new family is likely justifiable, since it exhibits some characters similar to several diverse calcaxonian taxa, and has unique features as well, but such an outcome awaits supporting molecular evidence. The new genus and species is remarkable among most octocorals in that it has an axis that is quadrangular in transverse section as in the calcaxonian Flagelligorgia gracilis and the pennatulacean Funiculina quadrangularis, and an apparently uniform, solid, highly calcified axial structure that lacks concentric layers or prismatic radiating wedges. In addition, it has distinctive sclerites of the surface coenenchyme that are predominantly elongate warty spindles with median waists, some of which superficially resemble sclerites found in some species of ellisellid gorgonians, but also exhibit ultrastructural features that differentiate them.

A new genus and species of pennatulacean octocoral from equatorial West Africa (Cnidaria, Anthozoa, Virgulariidae).

A new genus and species of sea pen or virgulariid pennatulacean from the Gulf of Guinea in the tropical eastern Atlantic is described, and a key to the genera of the Virgulariidae is included. The new genus and species described here adds to the previously described five other genera of the family. It is distinguished by unique sclerite and polyp leaf characters from the superficially-similar genus Virgularia, which lacks conspicuous sclerites in the polyp leaves and coenenchyme (other than minute oval bodies that are generally <0.01 mm in length).

Two new species of gorgonian octocorals from the Tropical Eastern Pacific Biogeographic Region (Cnidaria, Anthozoa, Gorgoniidae).

The gorgoniid Eugorgia is exclusively an eastern Pacific genus. It has a wide geographic and bathymetric range of distribution, found from California to Perú and extends down to 65 m deep. Two new species are herein described. The morphological characters were analyzed and illustrated by light and scanning electron microscopy. Eugorgia beebei sp. n. can be distinguished by its white, ascending, sparse colony growth. Eugorgia mutabilis sp. n. can be distinguished by its white colony that changes color after collection, and the conspicuous sharp-crested disc sclerites. From a morphological point of view the new species are related to the daniana-group, the rubens-group and the siedenburgae-group of Eugorgia; their affiliations, and the proposal of a new group are discussed. These new species increases the number of species in the genus to 15, and contribute to the knowledge of the eastern Pacific octocoral biodiversity.

New taxa and revisionary systematics of alcyonacean octocorals from the Pacific coast of North America (Cnidaria, Anthozoa).

A taxonomic assessment of four species of octocorals from the northeastern Pacific Ocean (British Columbia to California) is provided. Included here are a new species of clavulariid stolonifieran Cryptophyton, a new species of the nephtheid soft coral Gersemia, an undetermined species of soft coral in the genus Alcyonium that has been referred in the literature by several other names, and a new genus is named for a plexaurid sea fan originally described in the Indo-Pacific genus Euplexaura. Discussions are included that compare the species to related taxa, or provide revisionary assessments.

The global diversity of sea pens (Cnidaria: Octocorallia: Pennatulacea).

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.

Milolides G-N, new Briarane diterpenoids from the Western Pacific octocoral Briareum stechei.

Twelve new briarane diterpenes, designated milolides (1-12), and one known diterpene, 9-deacetylstylatulide lactone (13), were isolated from the Micronesian octocoral Briareum stechei collected at Yap, Federated States of Micronesia. Their structures were determined from spectral data.