identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
1493EC492A43534EA930E0045E4EF9C0.text	1493EC492A43534EA930E0045E4EF9C0.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Hemicorallium osmanthogemmum Koido 2026	<div><p>Hemicorallium osmanthogemmum sp. nov.</p><p>Figs 1, 2, 4, 5</p><p>New Japanese name.</p><p>Kinmokusei-mizo-sango.</p><p>Type material.</p><p>Holotype: KBF - OA -00436; Off Cape Ashizuri, Tosashimizu City, Kochi Prefecture, depth 550 m, July 2016, coll. Keiji Takami . Paratype: KBF - OA -00437, Off Cape Ashizuri, Tosashimizu City, Kochi Prefecture, depth 550 m, July 2016, coll. Keiji Takami .</p><p>Diagnosis.</p><p>The colony branches in one plane, and anastomoses are present only where broken branches come into contact with other branches. Autozooids are contracted but not retracted, and they are distributed only on one side of the colony. Spacing is almost absent on the twigs, and clusters are formed at the tips. The axis has no pits beneath the autozooids and is pale pink to pink in colour. Sclerites are predominantly radiate, and double clubs are rare. Warty rods are present only in the tentacles.</p><p>Description of holotype.</p><p>Colony. The holotype colony is fan-shaped and preserved in a dried state. It is approximately 12 cm in height and 13 cm in width. The colony branches in one plane from the main stem; partial fusion is present at sites of branch fracturing, and direct fusion between intact branches is generally absent (Fig. 1 A). The basal diameter is 9.3 mm, and the cross-section is nearly circular. The surface of the coenenchyme is covered with conical protuberances that become more pronounced toward the branch tips, forming longitudinal grooves as the projections align (Fig. 1 E).</p><p>Polyps. Contracted autozooids are restricted to one side of the colony (Fig. 1 A) and occasionally form clusters of two or three polyps at the branch tips (Fig. 1 E). On the stem, autozooids are typically spaced approximately 4–5 mm apart; however, some occur in direct contact with each other, whereas others are separated by more than 10 mm. They do not completely retract into the coenenchyme, but contracted autozooids form cylindrical mounds with eight longitudinal streaks that are continuous with the tentacles. The mounds measure approximately 1.3–2.0 mm in diameter and 1.0– 1.5 mm in height, with the diameter generally exceeding the height. Minute siphonozooids occur around the autozooids but are barely discernible to the naked eye (Fig. 1 D).</p><p>Axis. The axis is solid, lacking internal cavities. The surface is smooth without longitudinal grooves. There are no pits at the bases of the polyps (Fig. 1 C). The axis tapers toward the pointed branch tips, and a few commensal burrows are present along the axis (Fig. 1 D).</p><p>Colour. According to the collector, the fresh coenenchyme was orange, with no colour difference from the autozooids. The dried coenenchyme and polyps are pale orange and the axis is pink; no colour variation was observed between the branch tips, base, or interior. Sclerites are a mixture of colourless and extremely pale orange.</p><p>Sclerites. The sclerites comprise 6–8 - radiates, double clubs, and rods. Coenenchymal sclerites are predominantly made up of 6 - and 8 - radiates, whereas rods occur exclusively on the tentacles where they predominate (Figs 2, 3). Double clubs and 7 - radiates are rare throughout the colony. SEM measurements are as follows: rods are 0.060 –0.124 mm long and 0.009 –0.049 mm wide; 6 - radiates are 0.051 –0.056 mm × 0.034 –0.037 mm; 7 - radiates are 0.051 –0.059 mm × 0.033 –0.036 mm; 8 - radiates are 0.057 –0.087 mm × 0.031 –0.041 mm; double clubs are 0.055 –0.062 mm × 0.038 –0.040 mm.</p><p>Variation.</p><p>Another specimen (KBF - OA -00437) was attached to a rock. Similar to the holotype, the colony branches in a single plane, with contracted autozooids distributed only on one side of the colony (Fig. 4 A). Cluster formation occurs occasionally at the branch tips. Many terminal branches are broken and missing. The mounds are slightly larger than those of KBF - OA -00436, measuring 1.9–2.2 mm in diameter and 1.5–1.8 mm in height. The shape, maximum size, and dominant types of sclerites in each body part are consistent with those of KBF - OA -00436; however, the minimum sclerite size is smaller in KBF - OA -00437 (Fig. 5). The axis is slightly paler pink than that of specimen KBF - OA -00436, although it is still darker than the coenenchyme.</p><p>Remarks.</p><p>The 6 - and 8 - radiate sclerites can further be divided into “ symmetric ” and “ asymmetric ” forms. “ Symmetric ” forms have been considered an intermediate between radiates and double-club types (Nonaka and Hayashibara 2021; Nonaka et al. 2023; Hu et al. 2025); therefore, the boundaries between these three shapes are ambiguous. In this study, sclerites with two clearly defined handles were categorised as double-club types, following the criteria of Nonaka and Hayashibara (2021). Sclerites in the tentacles are predominantly rod shaped, whereas 6 - and 8 - radiate types dominate in the mounds, branch tips, and basal regions (Fig. 3). Among the previously described 24 species of Hemicorallium, H. abyssale (Bayer, 1956) and H. sulcatum (Kishinouye, 1903 b) are morphologically similar to this species, particularly in possessing pink axial skeletons and double-club sclerites. However, neither of these species form clusters of autozooids at the branch tips, and in H. abyssale, autozooids are distributed on both sides of the colony, which contrasts with H. osmanthogemmum sp. nov. Seven species — H. bathyrubrum (Simpson &amp; Watling, 2011); H. ducale (Bayer, 1955); H. guttatum Tu, Dai &amp; Jeng, 2016; H. indicodensum Hu, Zhang &amp; Xu, 2025; H. jiaolongensis Hu, Zhang &amp; Xu, 2025; H. meraboshi Nonaka, Hanahara &amp; Kakui, 2023; and H. tricolor (Johnson, 1899) — form autozooid clusters at the branch tips. However, none of these species have a pink axis, which differentiates H. osmanthogemmum sp. nov. from them. Additionally, the following six species cannot confidently be said to form autozooid clusters at branch tips based on the published descriptions: H. aurantiacum Tu, Dai &amp; Jeng, 2016, H. bayeri (Simpson &amp; Watling, 2011), H. imperiale (Bayer, 1955), H. maderense (Johnson, 1898), H. niobe (Bayer, 1964), and H. variabile (Thomson &amp; Henderson, 1906) . Among these, H. bayeri, H. maderense, H. niobe, and H. variabile can be distinguished from H. osmanthogemmum sp. nov. by their white axes, whereas H. aurantiacum and H. imperiale can be distinguished by their absence of double-club sclerites.</p><p>Etymology.</p><p>The specific name osmanthogemmum is derived from Osmanthus (sweet olive; Oleaceae) and the Latin gemma, meaning “ bud. ” This refers to the appearance of large autozooid mounds that are clustered at the distal ends of branches and resemble the floral buds of Osmanthus .</p></div>	https://treatment.plazi.org/id/1493EC492A43534EA930E0045E4EF9C0	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Koido, Tatsuki	Koido, Tatsuki (2026): A new species of Hemicorallium (Anthozoa, Octocorallia, Coralliidae), along with a revised identification key to species of the genus. ZooKeys 1277: 339-354, DOI: 10.3897/zookeys.1277.184620
