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Preliminary results of the deep-sea faunal survey conducted from the TR/V Seisui-maru of Mie University in April 2019 are presented. A total of 20 taxonomists and ecologists working on a wide variety of animal taxa participated in this survey. Surveyed areas included the Kumano Sea（off Mie Prefecture）and south of the Kii Strait（off Tanabe Bay, Wakayama Prefecture）， at depths of 112－775 m. Sampling gears employed were beam trawl and biological dredge. The collection is represented by macrobenthos and meiobenthos from nine animal phyla, including echinoderms, arthropods, molluscans and annelids. The number of phyla occurring in each station varied from seven to eight. The station with most diverse fauna at the phylum level was St. 3B（south of the Kii Strait, 775－661 m depth, mud bottom）．Meiofauna includes priapulids, nematodes and small arthropods such as copepods, tanaidaceans, amphipods, isopods and cumaceans. In addition to freeliving species, cnidarians symbiotic on a gastropod and an antipatharian, and crustaceans parasitic on a fi sh and sea urchins were also collected. Preliminary identifi cations are given for Asteroidea, Ophiuroidea, Holothuroidea, Crinoidea, Cyclopoida, Siphonostomatoida, Tanaidacea, Isopoda, Decapoda, Mollusca, polychaetes, Bryozoa, Cnidaria and Nemertea.

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Chironephthya cornigera sp. nov. (Figs. 8–3) urn:lsid:zoobank.org:act: 3D0575F0-A3AB-45F8-AAA2-E56ACCD1FD5B Japanese name: Tsuno-kudayagi Holotype. NSMT-Co 1704, at 11 m depth, Koh Rin, off Pattaya, Chonburi Province, Thailand (12°47.44'N, 100°42.18'E), on 13 October 2013. No. MT 424942 (mtMutS), MT 414717 (COI), MT 419963 (28SrDNA). Paratype. NSMT-Co 1705, at 13 m depth, same locality and same date as the holotype. No. MT 424943 (mt- MutS), MT 414718 (COI). Description of the holotype. Colony form: Colony, 40 mm high, consisting of seven polyparia arising from a thick cylindrical common base, 6 x 7 mm in the maximal diameter and 25 mm long, attached to a dead scleractinian coral, soft in life (Fig. 8A) but stiff in ethanol (Fig. 9A). Common base covered with many hydrozoan polyps and membranous bryozoans, and in the interior, there are several thick canals, 0.5–1.5 mm in diameter, running through its length. Lower portion of each polyparium are short stems, 3–7 mm long and 3 x 3.5–3 x 4 mm in diameter near the proximal portion. Polyparia 11–47 mm high (including lower stem), sparsely branched in all directions. Some of these branches branch off into a few secondary branches. Terminal branches are cylindrical and long, reaching 19 mm long and 3.5 x 4 mm in diameter, whether primary or secondary branch. In the interior of stem five to seven thick canals leading to apical polyps and an additional three to five thin canals. Canal walls are thin, soft and limp. Polyps: Monomorphic polyps with calices, occur independently at wide intervals, 2–3 mm, at the lower portion of the stem (Fig. 10B), but at the upper portion, the interval gradually narrows, and in some cases, they occur together. At the distal end portion of the branch, 5–7 polyps gathered, and just below which, two to eight polyps sur- round the branch (Fig. 10D, E). Below these, single polyps occur in a generally oblique row around the branch (Fig. 10A). In a few cases, a young polyp arises from the proximal portion of the calyx of large polyps. Calyces, in two types, cup-shaped (Fig. 10D) at distal portion of terminal branches, and shelf-like (Fig. 11A, B) on lateral sides of branches and stem. Both types of calyces supported by two to three teeth formed by seven to nine large, sometimes bifurcated spindles of Sclerites of coenenchyme: Surface layer of branches covered tightly with vertically aligned many large spindles of Color: Colony orange, reflecting the color of large spindles, with whitish tentacles and red crown in life. These colors hardly change in ethanol. Etymology. Specific name cornigera is a Latin word corniger = bearing horns, referring to the colony shape in life. Variability among type material. Paratype similar in colony form, distribution of polyps, sclerites, and anthocodial formula, but different in its yellowish color from the holotype. Remarks. This new species differs from other species of Chironephthya in that, like C. sirindhornae sp. nov., it has multiple stems arising from a common base and lacks large spindles in the interior of coenenchyme. This new species is distinguished clearly from the former species C. sirindhornae sp. nov. due to its limited branching, the small number of small spindles of the point, the presence of sclerites in its pinnules, and its many branching spindles at the cortex of the branches. The branched horn-like appearance of the living colony of this species is similar to that of Nidalia macrospina Kükenthal, 1906. However, the calyces of these specimens are shelf-like as in the ge- nus Chironephthya, not truncated and conical as in the genus Nidalia. The appearance of this species in life is also similar to the branched colony Eleutherobia dofleini (Kükenthal, 1906). However, E. dofleini is completely different from this species because in Eleutherobia, the calyx is fleshy and the sclerites of the cortex of coenenchyme are barrel-shaped. Further, the appearance of living colony of this species is similar to that of the genus Nephthyigorgia (Fabricius & Alderslade (2001: p. 133, fig. 4), but the calyces of it are cylindrical or conical, which are different from the shelf-like form of the genus Chironephthya.

Chironephthya sirindhornae sp. nov. (Figs. 2���7) urn:lsid:zoobank.org:act: 4FD6B1EF-8175-4326-BDB3-F2CD9DAD3A96 Japanese name: Hime-kudayagi Holotype. NSMT-Co 1703, at 19 m depth, Hin Lom Fang, off Pattaya, Chonburi Province, Thailand (12��48.37'N, 100��42.35'E), on 13 October 2013. GenBank Accession No. MT 424941 (mtMutS), MT 414716 (COI), MT 419962 (28SrDNA). Description. Colony form: Colony, 34 mm high, consisting of nine polyparia arising from a thin membranous common base, spreading over the dead holaxonian axis of 55 mm long and 3���13 mm wide, soft and somewhat translucent in life (Fig. 2) but stiff and opaque in ethanol (Fig. 3). Inside the common base, there are several canals, 0.2���0.6 mm in diameter, penetrated. Lower portion of each polyparium is a short sterile stem, 3���14 mm long and 2.0 x 2.5���5.2 x 6.5 mm in diameter in the proximal portion. Polyparia 7���47 mm high (including lower stem), sparsely branched in one plane. Terminal branches short, rod-like when alive, but deformed into club-shape with distal swollen portion with slightly withered polyparia after fixation, 2���4.6 mm long and 1.5 x 2.0��� 4.8 x 5.2 mm in diameter at the most swollen portion. The interior of stem, there are four to six thick canals leading to apical polyps and other two to three thin canals. Canal walls are thin, soft and limp. Polyps: Polyps monomorphic, distributed at long intervals on the upper stem (Fig. 4B), arranged sparsely, somewhat in a spiral formation on the lateral sides of branches (Fig. 4A), and crowded 4���6 in number at the distal portion of each terminal branch (Fig. 4D, E). Calyces, in two types, cup-shaped (Fig. 4E) at distal portion of terminal branches, and shelf-like (Fig. 4A, 5A, B) on lateral sides of branches and stem. Both types of calyces supported by 2���3 teeth formed by 5���7 large spindles of Sclerites of coenenchyme: Surface layer of branches covered tightly with vertically aligned large spindles of Color: Colony translucent pale pink, with yellow point sclerites and red crown sclerites in life. The color of colony changes to opaque dull pale pink in ethanol. Etymology. The specific epithet is named in honor of Her Royal Highness Princess Maha Chakri Sirindhorn of Thailand, who has initiated and implemented the Plant Genetic Conservation Project for maintenance and conservation of biodiversity both on land and in the ocean. Remarks. This new species differs from other species of Chironephthya in that it has multiple stems arising from a common base, and lacks large spindles in the interior of the coenenchyme. This species is distinguished clearly from its congener C. macrospiculata Thomson & Henderson, 1906 by the size of coenenchyme cortical spindles (Scleronephthya, but the presence of the calyx existing at the proximal portion of polyps and vertically-aligned spindles on the cortex of the coenenchyme enables distinguishing between them underwater, if carefully observed., Published as part of Imahara, Yukimitsu, Chavanich, Suchana, Viyakarn, Voranop, Kushida, Yuka, Reimer, James D. & Fujita, Toshihiko, 2020, Two new species of the genus Chironephthya (Octocorallia, Alcyonacea, Nidaliidae Siphonogorgiinae) from the Gulf of Thailand, pp. 324-340 in Zootaxa 4780 (2) on pages 328-332, DOI: 10.11646/zootaxa.4780.2.6, http://zenodo.org/record/3842504, {"references":["Thomson, J. A. & Henderson, W. D. (1906) An Account of the Alcyonarians Collected by the Royal Indian Marine Survey Ship Investigator in the Indian Ocean. Part 1. The Alcyonarians of the Deep Sea. Indian Museum, Calcutta, 132 pp., 10 pls. https: // doi. org / 10.5962 / bhl. title. 8279"]}

In this study, we had investigated the benthic deep-sea fauna using the dredge and beam trawl in the region from the continental shelf to the continental slope of the Sea of Kumano, Mie Prefecture, during the No．1722 research voyage of the training ship Seisui-Maru of Mie University. The survey was carried out at 16 stations covering a depth range of 113－1059 m. The results of the survey, 14 phyla had been confirmed. Arthropod, echinoderm, annelid and molluscan macrobenthos were collected from all of the stations. The phylum number of each station was in the range from 4 to 11. The largest number of phyla had been confi rmed at St．10D of boulders bottom（768－800 m depth）. Meiobenthos confi rmed in our sample were kinorhynchs, nematodes, tardigrades, loriciferans and small arthropods such as tanaidaceans, copepods and cumaceans. In addition to free-living species, parasitic copepods, isopods, platyhelminthes, acanthocephalans and nematodes had been found in fish, crustaceans and polychaetes.