taxonID	type	description	language	source
03CDBE44E97BFFE37495576B120AA99E.taxon	description	urn: lsid: zoobank. org: act: B 52 CEF 8 B- 0782 - 44 C 4 - BF 42 - 93 B 71 F 07396 B Figs. 3, 4	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	materials_examined	Material examined: Holotype: MBM 286456, station FX-Dive 215 (10 ° 05.05 ′ N, 140 ° 10.60 ′ E), a seamount (temporarily named as M 5) located on the Caroline Ridge in the tropical northwest Pacific, 1081 m, 2 June 2019.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	diagnosis	Diagnosis: Colony relatively short. Axis closely coiled with helical turn 5 – 7 cm high. Polyps small and curved with tentacular part nearly perpendicular to the body. Sclerites rods and needles without scales, all slender and nearly smooth, occasionally with sparse small warts. Polyps and branches with a few low verrucae.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	description	Description: Holotype about 50 cm long with the holdfast not recovered after collection, with only a few branches alive on the top in situ (Fig. 3 A, B). The direction of growth clockwise. Axis closely coiled spiraling upward and with dark iridescent metallic luster, about 4 mm in diameter at base. Branches not present on lower part, upper section of about 30 – 40 cm with 6 helical turns and each turn 5 – 7 cm long and 1 – 3 cm in diameter. Branches arc-shaped, up to 15 cm long with as many as 29 polyps counted, producing from the middle to top and arranged along one side of the axis, 2 – 3 mm apart. Polyps small and curved, 1.0 – 1.5 mm in height and up to 2.5 mm in width at base, 3 – 4 mm apart (Fig. 3 C – F). Tentacles incomplete contractile, up to 1 mm long and 1 mm wide. Polyps and branches with a few low verrucae. Sclerites all slender and nearly smooth, occasionally with sparse small warts, and scales absent. Rods and needles in the back of tentacle rachis longitudinally arranged, some of them with sparse small warts or shallow cracks on surface, and measuring 148 – 607 × 12 – 49 μm (length × width, the same below, Fig. 4 A). Rods and needles in the polyp body wall usually longitudinally arranged in the upper part and transversely in the basal part, occasionally crossed and with sparse small warts, and measuring 125 – 559 × 19 – 56 μm (Fig. 4 B). Needles in coenenchyme arranged along the branch, thick and usually with one or two sharp ends, some of them a little curved and with an irregular outline, and measuring 167 – 946 × 14 – 70 μm (Fig. 4 C). Sclerites usually abundant in the coenenchyme on the side bearing the polyps, and sparse to absent on the other side (Fig. 3 E, F).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	materials_examined	Type locality: A seamount (temporarily named as M 5) located on the Caroline Ridge with water depth of 1081 m.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	etymology	Etymology: The species name curva is derived from the Latin adjective curvus, referring to the curved shape of the polyps.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	distribution	Distribution and habitat: Found only from a seamount located on the Caroline Ridge. Colony growing on a rocky bottom with a white holdfast and with some fouling hydrozoans (Fig. 3 A). The water temperature was 4.2 ° C and the salinity 36.6.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE37495576B120AA99E.taxon	discussion	Remarks: Iridogorgia curva sp. nov. is characterized by small and curved polyps, slender sclerites without scales. It is similar to I. splendens Watling, 2007, I. densispiralis Xu, Zhan & Xu, 2021 and I. verrucosa Xu, Zhan & Xu, 2021 in short colony and close helical turns. Iridogorgia splendens, originally described by Watling (2007), was inadequately characterized; a revised description is provided in this study (see below). This species is distinguished by abundant rods and needles in the polyp body wall, featuring fine warts, sparse warty rods at the tentacle bases, and rare to absent needles in the inter-polyp coenenchyme. Iridogorgia curva sp. nov. differs from I. splendens in having relatively sparse and slender sclerites with fewer warts in both the polyp body wall and tentacles (vs. numerous, stout sclerites with abundant warts) (Watling 2007). Iridogorgia densispiralis and I. verrucosa, both described by Xu et al. (2021), differ in their morphological features. Iridogorgia densispiralis possesses rods, needles and a few flat rods (previously mischaracterized as thick elongated scales) in the polyp body wall, sparse warty rods at the tentacle bases, and rods and needles in the coenenchyme. In contrast, I. verrucosa is characterized by flat rods and needles with irregular edges in the polyp body wall and coenenchyme, sparse warty rods at the tentacle bases. Iridogorgia curva sp. nov. distinguishes itself from these two species through its distinct slender sclerites in the polyp body wall and coenenchyme, along with the absence of flat and relatively stout rods in the polyp body wall.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE67495515C1001A871.taxon	type_taxon	Type species: Iridogorgia pourtalesii Verrill, 1883, by monotypy.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE67495515C1001A871.taxon	diagnosis	Diagnosis (modified after Watling 2007, Xu et al. 2021): Chrysogorgiids with branches emanating from one side of the axis or spiralling around the axis. Main axis monopodial, wavy or coiled spiraling upward with a brilliant iridescence. Polyps uniserially arranged, spaced well, when sexually mature with base expanded along upper side of branches. Sclerites rods, needles, or scales, sometimes branched or with coarse sculptures. Branch coenenchyme with sclerites oriented along branches or without sclerites between polyps.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE67495515C1001A871.taxon	distribution	Distribution: Western and central Pacific, north and central east Atlantic, eastern Indian Ocean, 558 – 2311 m (Xu et al. 2021).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97BFFE67495515C1001A871.taxon	description	Based on the features of axis, branches and sclerites, a key is given to distinguish the species of Iridogorgia based on Xu et al. (2021). Iridogorgia bella, described by Nutting in 1908, is based on an incomplete type specimen with a vague original description. The true colony shape and the sclerites in each part remain unknown, necessitating further examination of the type specimen. Consequently, it is temporarily excluded from this key.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	description	Figs. 5 – 7	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	materials_examined	Material examined: MBM 286457, station FX-Dive 222 (10 ° 07.95 ′ N, 140 ° 14.40 ′ E), a seamount (temporarily named as M 6) located on the Caroline Ridge in the tropical northwest Pacific, depth 1077 m, 6 June 2019.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	diagnosis	Diagnosis (redefined on the basis of Watling 2007): Colony relatively short. Axis closely coiled with helical turn 4 – 5 cm long. Polyps with an expanded body base and abundant sclerites, including rods and needles with fine warts. Rods sparse and longitudinally arranged at the tentacle bases. Sclerites in coenenchyme between the polyps rare to absent.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	description	Description: Specimen deep orange after collection, about 56 cm long with the holdfast rounded and white about 3 cm in diameter (Fig. 5 B). The direction of growth clockwise. Axis closely coiled spiraling upward and with iridescent metallic luster, about 6 mm in diameter at base. Branching part about 33 cm long, including seven helical turns with each turn 4 – 5 cm long and 1 – 2 cm in diameter. Branches slightly arc-shaped, up to 15 cm long, 2 – 3 mm apart, and arranged along one side of the axis, with 21 polyps counted. Polyps with an expanded body base, 1.0 – 1.5 mm in height, 1 – 3 mm in width at base, and 3 – 8 mm apart (Fig. 5 C – G). Tentacular part usually gathered and dome-shaped after fixation, about 1 mm long and 1.0 – 1.5 mm wide. Proximal polyps small, sometimes with extended tentacles (Fig. 5 F, G). Polyps and branches with rare verrucae. Sclerites thick and often with irregular outline and unevenly distributed small warts (Fig. 6 C), scales absent. Rods in the back of tentacle rachis sparse and longitudinally arranged at the base, some of them irregular and with shallow cracks on surface, occasionally crossed, and measuring 132 – 471 × 12 – 100 μm (Figs. 5 H; 6 A). Needles and rods in the polyp body wall transversely arranged, some of them branched or crossed with irregular shape and rugged surface, occasionally with large warts, and measuring 130 – 1200 × 18 – 162 μm (Figs. 5 I; 6 B). Needles in the coenenchyme arranged along to the branch, slender and usually with two pointed ends, and measuring 161 – 1246 × 16 – 123 μm (Figs. 5 J, 6 D).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	distribution	Distribution: Rehoboth Seamount and Kelvin Seamount in the northwest Atlantic, 1844 – 2054 m (Watling 2007); a seamount located on the Caroline Ridge in the western Pacific, 1077 m.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E97EFFFF7495571B1449AC3E.taxon	discussion	Remarks: This specimen matches well with the holotype in its short colony with relatively tightly coiled central axis, short polyps with expanded body base, sparse sclerites at the tentacle bases, sclerites rare to absent in the coenenchyme between the polyps. Moreover, their 28 S gene sequences showed they are identical with the intraspecific differences (see the genetic analysis above). This specimen differs from the holotype and paratypes by more irregular sclerites in the polyp body wall and tentacles (Figs. 6, 7; Watling 2007). However, these differences may be caused by inadequate measurement and description of the holotype, which needs redescription.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	description	urn: lsid: zoobank. org: act: 761229 ED- 48 DB- 4252 - AD 06 - B 40 C 84 F 64 EA 6 Figs. 8 – 10	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	materials_examined	Material examined: Holotype: MBM 286365, station FX-Dive 68 (139 ° 17.86 ′ N, 11 ° 19.86 ′ E), a seamount (temporarily named as M 2) near the Mariana Trench in the tropical northwest Pacific, depth 672 m, 25 March 2016. Paratype: BPBM D 2954, MOL 501 - 1, Dive P 5 - 670, (21 ° 14.644 ' N, 156 ° 48.401 ' W) off Molokai Is. in the Hawaiian Island chain, depth 663 m, 4 September 2006.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	diagnosis	Diagnosis: Colony large with whip-like branches producing from the bottom to top. Axis coiled tightly and nearly straight with strong iridescent metallic luster. Polyps with an expanded body. Sclerites rods, usually thick with fine warts, some of them flattened and nearly smooth with rugged surface. Polyp and branch with a few verrucae.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	description	Description: Holotype incomplete, about 510 mm long, with the holdfast not recovered (Fig. 8 C). Axis tightly coiled spiraling upward and nearly straight with strong iridescent metallic luster, about 6 mm in diameter at base. The direction of growth clockwise. Branches whip-like and very flexible, up to 40 cm long, arranged on one side of the axis, 2 – 3 mm apart, with approx. 75 polyps counted, emanating from the bottom to top of the colony. Each helical turn about 3 cm in height. Polyp orange after collection and became light yellow to white after fixation (Fig. 9 A, C, D), with an expanded body, average 3 mm wide and 1 mm from the branch to the tentacle base. Polyps 1 – 3 mm apart at proximal part of the branches, up to 5 mm in distal. Tentacles 2 – 3 mm long when spread out. Some polyps and branches covered with a few verrucae (Fig. 9 G). Sclerites all rods, usually thick with small warts, some of them flattened and nearly smooth with rugged surface (Fig. 10). Rods in tentacle base longitudinally arranged, usually with small warts and two rounded ends, some of them nearly smooth and crossed with a few large warts or a rugged surface, measuring 106 – 412 × 22 – 98 μm (Fig. 10 A). Rods in the polyp body wall transversely or obliquely arranged, usually with sparse fine warts, some of them flattened and nearly smooth with a slightly medial contraction, occasionally crossed and curved with a few large warts, and measuring 91 – 580 × 20 – 75 μm (Fig. 10 B). Rods in the coenenchyme arranged along to the branch, nearly smooth, occasionally with small warts and irregular shape, and measuring 123 – 820 × 26 – 94 μm (Fig. 10 C).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	materials_examined	Type locality: An unnamed seamount (temporarily named as M 2) near the Mariana Trench with water depth of 672 m.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	etymology	Etymology: The species named according to its shape resembling the wookie in the Star Wars movies.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	distribution	Distribution and habitat: Holotype found on a seamount near the Mariana Trench. Colony large and lush in situ and growing on a rocky bottom (Fig. 8 A, B, D). The water temperature was 6.0 ° C and the salinity 36.3. Paratype from off Molokai, Hawaiian Is. Additional specimens photographed in the western Pacific Ocean.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E962FFFF749553A61261ABBA.taxon	discussion	Remarks: Iridogorgia chewbacca sp. nov. is characterized by tightly coiled and nearly straight axis with short helix, long and whip-like branches producing from colony bottom to top and sclerites all rods. The nearly straight axis can be seen as a special wavy shape with a narrow helical turn in diameter. Iridogorgia chewbacca sp. nov. is most similar to I. superba Nutting, 1908 but differs by tentacles with abundant sclerites (vs. absent), and longer branches (up to 400 mm vs. up to 175 mm) (Nutting 1908).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	description	Figs. 11, 12	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	materials_examined	Material examined: MBM 286361, station FX-Dive 57 (21 ° 11.80 ′ N, 118 ° 04.00 ′ E), Northeast of South China Sea, depth 1641 m, 5 March 2016.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	diagnosis	Diagnosis (redefined on the basis of Xu et al. 2021): Colony relatively short with closely coiled helices and branches producing nearly from the bottom to top. Polyps with an expanded body base. Rods in the tentacles relatively sparse with many small warts, some of them with a slight medial contraction. Flat rods and needles in the polyp body wall and coenenchyme often with a slight medial contraction, some of them wide with irregular shape. Sclerites in coenenchyme abundant at the base of polyps and rare to absent in inter-polyps.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	description	Description: Colony grown in a rocky bottom in situ (Fig. 11 A). Specimen bright orange after collection and became white after fixation, about 43.5 cm long, with the holdfast not recovered (Fig. 11 B, C). The direction of growth clockwise. Axis closely coiled spiraling upward and with an iridescent metallic luster, about 5 mm in diameter at base. Branching part including 14 helical turns, each turn about 3 cm in height and 1 cm in diameter (Fig. 11 C). Branches up to 200 mm long, producing nearly from the colony base to top and arranged on one side of the axis, about 2 mm apart. Polyps with an expanded body base, about 3 mm wide and 1 mm from the branches to the tentacle bases, 5 – 7 mm apart (Fig. 11 D, E, G – I). Tentacles up to 3 mm when spread out. The proximal polyps usually with a more expanded body base, shorter tentacles, and longer inter-polyp distance. Polyps and branches with a few low verrucae (Fig. 11 I). Rods in the tentacle bases longitudinally arranged, sparse and large with two rounded ends, usually covered with many small warts and a slight middle constriction, some of them with a rugged surface, and measuring 200 – 487 × 19 – 63 (Figs. 11 J, K; 12 A). Flat rods and needles in the polyp body wall transversely or obliquely arranged, nearly smooth, some of them with a slight middle contraction and sharp ends, occasionally crossed, wide and irregular, measuring 96 – 407 × 12 – 106 µm (Figs. 11 J, K; 12 B). Sclerites rare to absent in inter-polyp coenenchyme (Fig. 11 F). Flat rods and needles in coenenchyme at the base of polyps nearly smooth, some of them with two sharp ends, occasionally branched, and measuring 174 – 419 × 19 – 49 µm (Fig. 12 C).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	distribution	Distribution: A seamount located on the Caroline Ridge, 1397 m (Xu et al. 2021); South China Sea, 1641 m.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E961FFFA749556DD12B7ABF7.taxon	discussion	Remarks: This specimen matches well with the holotype in relatively tightly coiled central axis, sclerites rare to absent in the coenenchyme between the polyps, rods in tentacles and flat rods and needles in polyp body wall and coenenchyme. Moreover, their mtMutS-cox 1 and 28 S gene sequences showed they are identical with the intraspecific differences (see the genetic analysis before). Thus, we identified them as the same species. This specimen differs from the holotype by deeper color when alive, longer branches, less verrucae and relatively regular sclerites in polyp body and coenenchyme (Xu et al. 2021). However, these differences may be caused by different environment or growth stage, and we thus treat as the conspecific variation.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	description	Figs. 13 – 16	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	materials_examined	Material examined: MBM 286449, station FX-Dive 226 (10 ° 38.22 ′ N, 140 ° 04.08 ′ E), a seamount (tentatively named as M 8) located on the Caroline Ridge in the tropical northwest Pacific, depth 1971 m, 14 June 2019. MBM 286876, station FX-Dive 174 (17 ° 29.45 ′ N, 153 ° 14.01 ′ E), Kocebu Guyot of Magellan Seamounts in the northwest Pacific, depth 1311 m, 8 April 2018. BPBM D 2955, station HURL Dive P 5 - 672, specimen MOL 601 - 4 (21 ° 18.972 ′ N, 157 ° 1.282 ′ W), off Molokai Is., Hawaiian Island chain, depth 1661 m, 6 September 2006.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	diagnosis	Diagnosis (modified from Xu et al. 2020): Colony with loosely coiled helices. Polyp cylindrical with a slightly expanded body base. Rods in tentacles covered with many small warts. Needles and rods at the base of tentacles flattened and often with sparse fine warts. Needles and elongated scales in the basal part of polyp body wall thick and of various shapes, often with sparse fine warts, some with large sculpture on surface. Needles in coenenchyme slender and nearly smooth with two sharp ends. Polyps and branches with verrucae.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	description	Description: The three specimens match well with the description of I. squarrosa; herein the morphology of specimen MBM 286449 is described in more detail. Colony grows on a rocky bottom with a small holdfast in situ (Fig. 13 A). Specimen MBM 286449 about 75 cm long with holdfast white about 2.5 mm in diameter (Fig. 13 C). The direction of growth counterclockwise. Axis about 5 mm in diameter at base with dark iridescent metallic luster, including four helical turns with each turn 12 – 15 cm long and 1 – 2 cm in diameter. Branches arranged along one side of the axis, about 3 mm apart, and up to 17 cm long with 21 polyps counted. Polyps erect or slightly inclined along the branches, having a little contraction between the upper part and the slight expanded body base. Polyps cylindrical, 1 – 3 mm in height, 2 – 3 mm in width at base, and 4 – 8 mm apart (Fig. 13 B, D – G). Polyps white after fixation in alcohol. Tentacular part 1.0 – 1.5 mm long, 1 – 2 mm wide. Polyps and branches with a few verrucae. Rods in the back of tentacle rachis longitudinally arranged, slender with many small warts and two rounded ends, usually forming eight distinct columns extending from tentacles to bases, and measuring 209 – 465 × 19 – 42 μm (Fig. 14 A). Needles and rods at the base of tentacles longitudinally arranged, flattened and slender, often with sparse fine warts, occasionally nearly smooth, and measuring 317 – 555 × 35 – 76 μm (Fig. 14 B). Needles and elongated scales in the basal part of polyp body wall transversely or obliquely arranged, usually thick with various shape and sparse small warts, some of them nearly smooth and with large irregular sculpture on surface, and measuring 70 – 665 × 21 – 100 μm (Fig. 14 C). Needles in coenenchyme arranged along to the branch, slender and nearly smooth with two sharp ends, occasionally with fine warts, and measuring 126 – 1014 × 17 – 85 μm (Figs. 13 H, 14 D).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	distribution	Distribution: A seamount near the Mariana Trench, 1458 m; off Molokai, Hawaii, 1661 m (Xu et al. 2020); Kocebu Guyot in Magellan Seamounts, 1311 m; a seamount located on the Caroline Ridge, 1971 m.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E967FFF5749554EE10C4ACD2.taxon	discussion	Remarks: Compared with the holotype and specimen MBM 286876 (Fig. 15), specimens MBM 286449 and MOL 601 - 4 have none sclerites with the surface sculptured by something superficially similar to the ‘ styles’ of sponges. Their mtMutS and 28 S gene sequences showed they are identical with the intraspecific differences (see the genetic analysis above). Therefore, this morphological difference is not constant characters and can be treated as the intraspecific variation.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	description	Figs. 17 – 22	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	materials_examined	Material examined: MBM 286362, station FX-Dive 173 (17 ° 28.28 ′ N, 153 ° 10.54 ′ E), Kocebu Guyot of Magellan Seamounts in the northwest Pacific, depth 1303 m, 7 April 2018. MBM 286363, station FX-Dive 178 (17 ° 20.40 ′ N, 152 ° 41.88 ′ E), Kocebu Guyot, depth 1596 m, 12 April 2018. MBM 286458, station FX-Dive 211 (10 ° 03.18 ′ N, 140 ° 10.60 ′ E), a seamount (tentatively named as M 5) located on the Caroline Ridge in the tropical northwest Pacific, depth 1393 m, 29 May 2019. MBM 286459, station FX-Dive 224 (10 ° 37.63 ′ N, 140 ° 05.45 ′ E), a seamount (tentatively named as M 8) located on the Caroline Ridge, depth 1504 m, 12 June 2019. MBM 286452, station FXDive 211 (10 ° 02.93 ′ N, 140 ° 10.48 ′ E), a seamount (tentatively named as M 5) located on the Caroline Ridge, depth 1482 m, 29 May 2019.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	diagnosis	Diagnosis (modified from Watling 2007): Colony with closely coiled helices and branches at the top of the colony forming a beautiful fountain shape. Polyps cylindrical with a slight expanded body base. Rods in tentacles covered with many small warts. Needles and rods in the polyp body wall thick and nearly smooth, some of them flattened and broad. Needles in coenenchyme slender and nearly smooth. Polyps and branches with a few verrucae.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	description	Description: The four specimens (MBM 286362, 286363, 286458 and 286458) all match well with the previous description of I. fontinalis Watling, 2007; herein the morphology of specimen MBM 286459 is described in more detail. Colony growing on a rocky bottom with a small white holdfast in situ (Fig. 17 B). Specimen about 78 cm long with the holdfast not recovered (Fig. 17 F). The direction of growth clockwise or counter-clockwise (clockwise in MBM 286458, counter-clockwise in MBM 286362 and MBM 286363). Axis having 16 helical turns, uniformly coiled from the middle to top, about 4.5 mm in diameter at base with iridescent metallic luster. Each helical turn 4 – 6 cm long and 2 – 3 cm in diameter. The branching part about 15 cm in height including five helical turns. Branches arc-shaped forming a fountain spray shape, and arranged along one side of the axis, 1.0 – 1.5 mm apart, and up to 20 cm long with 32 polyps counted. Polyps cylindrical, usually with a slight expanded body base, 1 – 3 mm in height, and 2 – 5 mm in width at base (Fig. 18 D, F, G). Polyps 2 – 6 mm apart at the distal part of branch, and became sparse and up to 20 mm at the proximal part (Fig. 18 C). Tentacular part 1 – 2 mm long, 1.0 – 1.5 mm wide, usually forming eight obvious parallel columns terminating at its base. Polyps white after fixation. Polyps and branches with a few verrucae. Compared with the four specimens, another specimen MBM 286452 has some differences in morphology. It is about 130 cm in height with a long unbranched axis and the holdfast not recovered (Fig. 19 C). The direction of growth clockwise. Axis uniformly coiled from the bottom to top like a wire spring, having 26 helical turns, about 7 mm in diameter at base with light iridescent metallic luster. Each helical turn 4 – 6 cm long and 2 – 3 cm in diameter. Branching part about 20 cm in height with four helical turns. Branches 1.0 – 1.5 mm apart, and up to 20 cm long with 29 polyps counted. Polyp claret-colored or a little pink after fixation, 1 – 4 mm in height average 3 mm, and 2 – 3 mm in width at base, 3 – 5 mm apart (Fig. 19 D – G). Tentacular part 1 – 2 mm long, 1 mm wide. Some polyps with a large expanded body base and golden eggs visible under the light microscope (Fig. 19 F). Verrucae rare to absent in polyps and branches. The five specimens have similar sclerites. Their polyps and coenenchyme all covered with numerous sclerites (Figs. 18 F, G; 19 H, I). Rods in the back of tentacle rachis longitudinally arranged, slender and regular with two round ends and many small warts, occasionally with a few large irregular warts and shallow cracks on surface, and measuring 168 – 553 × 26 – 65 μm (Figs. 20 A, 21 A, 22 A). Needles and rods in the polyp body wall transversely or longitudinally arranged, thick and nearly smooth, some of them flattened, occasionally branched with irregular shape and large warts, and measuring 129 – 1039 × 21 – 129 μm (Fig. 20 C, 21 B, 22 B). Needles in coenenchyme arranged along to the branch, slender and thick with nearly smooth surface, occasionally with sparse fine or large warts, and measuring 143 – 1212 × 21 – 118 μm (Figs. 20 B, 21 C, 22 C).	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	distribution	Distribution: Atlantic: Corner Rise seamounts, 1325 m (Watling 2007); Pacific: Kocebu Guyot in Magellan seamounts, 1303 – 1596 m; seamounts located on the Caroline Ridge, 1393 – 1504 m. Additional specimens recorded in video from the Central Pacific. Two specimens (BPBM D 2946 and D 2947) collected on Twin Banks, Northwest Hawaiian Islands Ridge (23 ° 8.152 ′ N, 163 ° 9.301 ′ W), depth 1310 and 1384 m, attributed to this species, but not verified genetically.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
03CDBE44E968FFF1749553DF1305AC1A.taxon	discussion	Remarks: Our five specimens and the holotype of Iridogorgia fontinalis Watling, 2007 all have a fountain shape, similar helical height and diameter, branch interval, polyp size, and the same sclerite forms and arrangement. However, s pecimen MBM 286452 differs from others by a longer unbranched axis with more helices, claret-colored or a little pink polyps after fixation. These differences are not constant characters and may be caused by different growth stage and environment, and can be treated as the intraspecific variation. Based on the morphological and phylogenetic analyses, the five specimens were all identified as the same species. Iridogorgia fontinalis is a newly recorded species in the Western Pacific.	en	Xu, Yu, Watling, Les, Zhan, Zifeng, Xu, Kuidong (2025): Studies on western Pacific gorgonians (Anthozoa: Octocorallia: Chrysogorgiidae). Part 2: unexpected diversity of the genus Iridogorgia in the tropical western Pacific with descriptions of two new species. Zootaxa 5689 (3): 451-486, DOI: 10.11646/zootaxa.5689.3.3, URL: https://doi.org/10.11646/zootaxa.5689.3.3
