Deep-sea (>1000 m) Goniasteridae (Valvatida; Asteroidea) from the North Pacific, including an overview of Sibogaster, Bathyceramaster n. gen. and three new species
Three new species of antipatharian corals are described from deep-sea (677–2,821 m) seamounts and ridges in the North Pacific, including Antipathes sylospongia, Alternatipathes venusta, and Umbellapathes litocrada. Most of the material for these descriptions was collected on expeditions aboard NOAA Ship Okeanos Explorer that were undertaken as part of the Campaign to Address Pacific Monument Science, Technology, and Ocean Needs (CAPSTONE). One of the main goals of CAPSTONE was to characterize the deep-sea fauna in protected waters of the U.S. Pacific, as well as in the Prime Crust Zone, the area with the highest known concentration of commercially valuable deep-sea minerals in the Pacific. Species descriptions and distribution data are supplemented with in situ photo records, including those from deep-sea exploration programs that have operated in the North Pacific in addition to CAPSTONE, namely the Hawaii Undersea Research Laboratory (HURL), the Ocean Exploration Trust (OET), and the Monterey Bay Aquarium Research Institute (MBARI).
Five new species of deep-sea antipatharian corals are described from the North Pacific primarily collected off the coast of Alaska and on adjacent seamounts. All the species are referred to the family Schizopathidae. Described as new are: Alternatipathes mirabilis, Bathypathes ptiloides, Bathypathes tiburonae, Bathypathes alaskensis, and Parantipathes pluma. Illustrations of the type material of Bathypathes patula, B. patula var. plenispina and B. tenuis are provided for comparative proposes. Bathypathes patula var. plenispina is here recognized as a species distinct from B. patula, and B. tenuis is considered incertae sedis due to the poor condition of the type material.
Three new species of the genus Dendronotus are described from the North Pacific waters of Japan and Russia. For the first time since 1949, three new species, D. jamsteci sp. nov., D. zakuro sp. nov. and D. bathyvela sp. nov. are described from the waters of the Japanese Islands. D. zakuro sp. nov. was also discovered in the waters of Russia (Kamchatka). The descriptions of the new species D. jamsteci sp. nov. and D. zakuro sp. nov. are based on morphological and molecular data; D. bathyvela sp. nov. morphologically belongs to the group of D. robustus, D. velifer and D. patricki. This study revises our knowledge of North Pacific species of the genus Dendronotus, considerably expands the number of species worldwide and contributes to the multilevel fine-scale diversity concept.
A new species of deep-sea jellyfish, Crossota millsae (Cnidaria: Hydrozoa: Trachymedusae: Rhopalonematidae), is described from the North Pacific Ocean off California and Hawaii. Discrete depth sampling showed this species lives at depths below 1000 meters in both geographic locations. The species is more abundant off California than off Hawaii. The greatest population densities were found at ~2500 m off California and at ~1250 m off Hawaii. The burnt-tangerine color of the inner bell and bright pink to lavender color of the ring and radial canals, manubrium and gonads make living specimens of this species difficult to confuse with any other known species of hydromedusa. Sexually dimorphic differences in gonad morphology are evident. The pendant testes contained spermatids at various stages of spermatogenesis as observed using scanning electron microscopy. Ova develop directly into small medusae that reside subumbrellarly between the radial canals of the mother. Various developmental stages of C. millsae are shown in photographs and terminology of brooding and viviparity is discussed relative to other Cnidaria.
Five new species of poecilosclerid sponges, Artemisina amlia sp. nov., Coelosphaera oglalai sp. nov., Melonanchora globogilva sp. nov., Tedania kagalaskai sp. nov., and Mycale carlilei sp. nov, are described from the Aleutian Islands, Alaska, from depths ranging between 100–190m and are compared with congeners of the North Pacific Ocean.Keywords: Taxonomy, Porifera, Demospongiae, Poecilosclerida, new species, N-Pacific, Aleutian Islands, Alaska
Two new species of Cumella (Cumacea: Nannastacidae), C. oculata and C. alaskensis are described from shallow Alaskan rocky shores. The new species C. oculata can be distinguished from other North Pacific Cumella by the combination of a large eye lobe, no spines dorsally on the carapace, and carapace without large tubercles. The new species C. alaskensis can be distinguished from the other North Pacific Cumella by the 5 spines distributed unequally on the dorsal crest.
New species of black corals (Cnidaria:Anthozoa: Antipatharia) from deep-sea seamounts and ridges in the North Pacific