taxonID	type	description	language	source
F45587D5FF91FF8DE97BFBE9FBA8F990.taxon	description	Other descriptions (Wieser, 1954: 81, fig. 142 a- d, Chile. Lorenzen, 1971: 290, fig. 5 a- d, North Sea) Synonymised names [Actinonema amphidiscatum (Schuurmans Stekhoven & Adam, 1931) Wieser, 1954; Actinonema fragile (Allgén, 1929) Wieser, 1954; Adeuchromadora megamphida Boucher & Bovée, 1972; Euchromadora fragilis Allgén, 1933; Pareuchromadora amphidiscata Allgén, 1940; Pareuchromadora amphidiscata Schuurmans Stekhoven & Adam, 1931; Pareuchromadora fragilis (Allgén, 1934); Spiliphera fragilis Allgén, 1929] Locality. The coast of Samsan-myeon, Goseong-gun, Gyeongsangnam-do: sub-tidal Eastern part of South Sea, Korea (34 ° 56 ʹ 2.1 ʺ N, 128 ° 15 ʹ 20.6 ʺ E), at a depth of 25 m, in the clay sediment.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF91FF8DE97BFBE9FBA8F990.taxon	materials_examined	Material. Three males (MABIK NA 00158042, MABIK NA 00158708 - MABIK NA 00158709) and One female (MABIK NA 00158710) collected by Jung-Ho Hong at the coast of Goseong on 2 nd May 2023, from Research Vessel Haeyanghwnangkyung 2.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF91FF8DE97BFBE9FBA8F990.taxon	description	Measurements. Check Table 1 for detailed measurements and morphometric ratios. Description. Males (Fig. 1, Table 1). Body cylindrical, uniform in thickness, gradually narrowing toward both ends; anterior apex blunt. Cuticle heterogeneous and complex, with irregular minute dots beginning at the anterior border of amphids. Transverse dots present in the anterior part of the pharynx; lateral differentiation starts anterior to the nerve ring (~ 50 - 60 μm from the anterior apex) with a reversed ‘ V’ shape. Double reversed ‘ V’ shaped lateral differentiation present from mid-body to anus, transitioning to irregular differentiation from near the anus to the posterior tail. Lateral differentiation diminishes in the distal two-thirds of the tail. Somatic setae inconspicuous, minute, and scattered. Labial region with six inner labial papillae and six outer labial setae (~ 3 μm) in a single circle, accompanied by four cephalic setae (~ 2 μm). Six solid cones surround the labial region. Stoma conical, bearing a sharply pointed dorsal tooth. Amphideal fovea conspicuous, transversely oval with a double contour, 10 - 11 μm wide (75 - 80 % of cbd), located posterior to the cephalic setae circle. Pharynx cylindrical, 130 - 135 μm long, with a distinct posterior bulb. Cardia inconspicuous. Excretory pore located just posterior to the nerve ring, 80 - 85 μm from the anterior body end. Reproductive system monorchic; single testis situated on the left side of the intestine. Spicules thin, curved, measuring 25 - 30 μm; talamons 27 - 31 μm long. Gubernaculum 20 - 23 μm, without apophyses. Precloacal supplements absent. Tail conical, tapering to a pointed tip, with three caudal glands and a well-developed spinneret. Females (Fig. 1, Table 1). Overall features similar to males. Reproductive system amphidelphic. Ovaries located to the left of the intestine, reflexed. Vulva slightly posterior to mid-body, positioned at 51.5 % of body length.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF91FF8DE97BFBE9FBA8F990.taxon	discussion	Remarks. To date, the genus Actinonema Cobb, 1920 contains 12 valid species: A. celtica Boucher, 1976, A. diplobulba Chu, Hao and Huang, 2023, A. dolichurum Gagarin and Long, 2017, A. falciforme Shi, Yu and Xu, 2018, A. fidatum Vitiello, 1970, A. grafi Jensen, 1991, A. longicaudatoides Gagarin, 2015, A. longicaudatum (Stein- er, 1918) Wieser, 1954, A. pachydermatum Cobb, 1920, A. paraceltica Muthumbi and Vincx, 1998, A. parvum Gagarin, 2015 and A. smolae Muthumbi and Vincx, 1998 (WoRMS Editorial Board, 2024; Nemys eds., 2024). Specimens from the eastern part of the South Sea, Korea, generally match the original description by Cobb (1920), with the exception of differences in body width (33 - 35 μm vs. 27 - 30 μm) and slight variation in body length (817 - 850 μm vs. 830 - 900 μm). These differences are considered intraspecific variations.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF93FF88E97BF93DFEEBFBBA.taxon	description	Other descriptions (de Man, 1922: 235 - 236, fig. 23 a- b, North Sea. Stekhoven, 1935: 148, fig. 325 a- c, North Sea. Stekhoven, 1942: 228, fig. 10 a- c, Mediterranean Sea. Gerlarch, 1957: 172, fig. 121 l- m, Brazil. Loof, 1961: 198 - 199, fig. 10 a- b, North Sea, reexamination of type specimen. Gerlarch, 1965: 170, fig. 44 a- c. Lorenzen, 1969: 209, fig. 10 a- d, North Sea. Fadeeva, 1983: 1324 - 1326, fig. 2 a- d, East Sea. Turpeenniemi, 1997: 72 - 81, fig. 4 a- h, Baltic Sea) Synonymised names (Sphaerolaimus buetschlii Schulz, 1932; Sphaerolaimus demani Filipjev, 1922; Sphaerolaimus setosus Paramonov, 1927) Locality. The coast of Ilgwang-myeon, Gijang-gun, Busan: sub-tidal zone Southern part of East Sea, Korea (35 ° 16 ʹ 0.0 ʺ N, 129 ° 16 ʹ 50.0 ʺ E), at a depth of 16 m, in the clay sediment.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF93FF88E97BF93DFEEBFBBA.taxon	materials_examined	Material. Three males (MABIK NA 00158050, MABIK NA 00158715 - MABIK NA 00158716) collected by Jung-Ho Hong at the coast of Gijang on 30 th April 2023, from Research Vessel Haeyanghwnangkyung 3.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF93FF88E97BF93DFEEBFBBA.taxon	description	Measurements. See Table 2 for detailed measurements and morphometric ratios. Description. Males (Fig. 2, Table 2). Body cylindrical, gradually tapering towards the tail end, about 1365 - 1520 μm long and 65 - 78 μm wide at the maximum body diameter. The cuticle finely striated with lateral alae measuring 10 - 15 μm in width, starting from the cervical region and extending to the base of the tail. Somatic setae in eight longitudinal rows, about 6 - 12 μm long in the cervical region, 5 - 7 μm long in the mid and tail part. The anterior end rounded with six small lips encircle the oral opening. Lip region rounded with six inner labial papillae. Six outer labial papillae and four cephalic setae (4 - 5 μm long) in one circle, anterior to buccal cavity. Subcephalic setae in eight groups situated, 2 - 3 setae (14 - 20 μm long) in each group. A series of longitudinal ridges located just in front of the buccal cavity. Buccal cavity barrel-shaped, C 23 - 32 μm long, 20 - 25 μm wide composed in two parts, thick-walled anterior part and a sclerotized, thin-walled posterior part. Amphideal fovea circular, 8 - 11 μm in diameter or 24 - 28 % of corresponding body diameter, located 23 - 33 μm from anterior apex. Pharynx nearly cylindrical, gradually expanding towards to the cardia, strongly muscular throughout its entire length. Cardia small, roundedconoid, surrounded by intestinal tissue. Nerve ring at 50 - 54 % of the pharynx length (140 - 181 μm long). Renette cell slightly behind the base of the pharynx, small oval shape, lateral to the intestine. Excretory pore near posterior to the nerve ring. Testes paired. Vas deferens well-developed. Spicules curved, 60 - 85 μm long along arch. Gubernaculum with dorsal-caudally directed apophysis 20 - 25 μm long. Precloacal supplements absent. Tail length 190 - 215 μm, conical anteriorly and cylindrical posterior- ly, pointed terminal end with three terminal setae (12 - 15 μm long). Three caudal glands open to the spinneret.	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
F45587D5FF93FF88E97BF93DFEEBFBBA.taxon	discussion	Remarks. Sphaerolaimus gracilis de Man, 1876 is characterized by the position of the amphid posterior to the buccal cavity; the length of spicules shorter than twice of anal body diameter; spicules not double jointed; spicules with consistent thickness; gubernaculum present; gubernaculum with straight dorsal apophyses (Zograf et al., 2020). Based on the original description by de Man in 1876 from the brackish water of Walcheren Island, Netherlands, other descriptions made by many authors in the North Sea, Spitsbergen, the East Sea, and so on. Our specimens from the East Sea, Korea are similar to the description by Fadeeva in 1983 from the East Sea, but slightly smaller in body width (65 - 75 μm vs. 60 - 83 μm) and body length (1365 - 1520 μm vs. 1300 - 1700 μm). There is also a slight difference in spicules length (55 - 70 μm vs. 45 - 55 μm) and the apophysis length of the gubernaculum (15 - 20 μm vs. 13 - 14 μm).	en	Hong, Jung-Ho, Kim, Kichoon, Lee, Seunghan, Lee, Young Ho Koh and Kanghyun (2025): Two new species records of the class Chromadorea Inglis, 1983 (Nematoda) from Korea. Journal of Species Research 14 (2): 206-212, DOI: 10.5281/zenodo.16967426
