taxonID	type	description	language	source
8618A692397C540BB620562A8E8DDC31.taxon	description	Fig. 1	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
8618A692397C540BB620562A8E8DDC31.taxon	diagnosis	Diagnosis. Small worm with size 41 – 57 mm by 1.0 – 2.5 mm (clitellum width). Segment numbers 86 – 104. Spermathecal pores four pairs, 5 / 6 – 8 / 9, medio-ventral, nearly inconspicuous. Spermathecae four pairs in VI – IX, ampulla oval; ampulla duct thick and stout, abruptly narrower towards ectal end; diverticulum with slender and long duct and ovoid receptacle; receptacle 1 / 3 length of the diverticulum duct. Diverticulum is the same length or slightly longer than the main pouch. Intestinal caeca simple, originating in XXVII extending anteriorly to XXI. Male pores and genital markings absent.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
8618A692397C540BB620562A8E8DDC31.taxon	description	Description. External characters. Length 41 – 57 mm, clitellum width 1.0 – 2.5 mm, narrower toward pre-clitellar region (n = 5). Color of preserved specimens may vary from shades because of the duration of preservation but generally dorsum region is brown to yellowish brown, while ventrum part is pale yellow. Segment numbers 86 – 104. Prostomium epilobous (Fig. 1 A). First dorsal pore on 12 / 13. Clitellum pale brown, annular and raised at XIV – XVI; setae or dorsal pores and intersegmental furrow absent. Setal arrangement perichaetine; setae number 32 – 35 (V), 34 – 37 (VII), 40 – 45 (XIII), 48 – 52 (XX). Spermathecal pores four pairs, 5 / 6 – 8 / 9, medio-ventral, nearly inconspicuous with 0.20 – 0.22 C apart ventrally. Male pores, pre-clitellar and post-clitellar genital markings absent (Fig. 1 B). Female pore single, circular in a slightly concave porophore medioventral at XIV (Fig. 1 C). Internal characters. Septa 5 / 6 / 7 slightly thickened, 7 / 8 thin, 8 / 9 / 10 absent, 10 / 11 / 12 / 13 / 14 thin. Gizzard within VIII – X, large and barrel-shaped (Fig. 1 F). Intestine enlarged from XV. Intestinal caeca are simple, originating in XXVII and extending anteriorly to XXI (Fig. 1 E). Esophageal hearts three pairs in X – XIII. Spermathecae four pairs in VI – IX. Ampulla oval; ampulla duct thick and stout, abruptly narrower towards ectal end (1.3 – 1.8 mm long); diverticulum with slender and long duct and ovoid receptacle (1.5 – 2.0 mm long); receptacle 1 / 3 length of the diverticulum duct. Diverticulum is the same length or slightly longer than the ampulla plus duct (Fig. 1 D). Male sexual system holandric, testes sac well-developed, two pairs in X and XI. Seminal vesicles, two pairs in XI and XII. Prostate glands and accessory glands absent.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
8618A692397C540BB620562A8E8DDC31.taxon	distribution	Distribution in China. Liaoning Province, Northeast China.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
8618A692397C540BB620562A8E8DDC31.taxon	etymology	Etymology. The specific name refers to the type locality, Dandong Prefecture; adjective.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
AFE0A675E8A35B4484DA04869B5E44C6.taxon	description	Figs 2, 3	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
AFE0A675E8A35B4484DA04869B5E44C6.taxon	diagnosis	Diagnosis (modified from Reynolds 2022). Size 70 – 200 mm length by 5 – 8 mm (clitellum width). Segment numbers 63 – 110. Spermathecal pores three pairs in 5 / 6 / 7 / 8. Pre-clitellar genital markings present or absent; when present, ventral, areas of slight epidermal modification on VII and / or VIII, occasionally on VI and IX, unpaired and median or symmetrically paired, forming setal gaps, epidermis finely wrinkled or crosshatched, sometimes darker in color in live specimens. Male pores usually absent; when present, small, transversely slit-like. Post-clitellar genital markings usually absent; when present, single, large circular pad, pre-setal on XVIII, just median to male pores, with a concave center surrounded by a narrow but distinct, raised rim, reaching posteriorly slightly behind the setal line on XVIII and anteriorly to the setal line on XVII. Spermathecae present or absent; when fully present, three pairs in VI – VIII, duct shorter than ampulla; diverticulum longer than the main pouch. Prostate glands present or absent; when present, extending through some or all of XVI – XXIII, ducts in XVIII. Accessory gland mostly absent, when present, large and paired in front of the setal line on segment XVIII. Intestinal caeca paired in XXVII extending anteriorly to XX, digitate.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
AFE0A675E8A35B4484DA04869B5E44C6.taxon	description	Description of Chinese specimens in this study. External characters. Length 80 – 94 mm by width 5.0 – 8.0 mm (n = 5). Color of live specimens reddish-brown. Color of preserved specimens may vary in shades because of the duration of preservation but generally brownish-yellow (with blackish highlights) throughout with milk gray clitellum. Number of segments 100 – 108. Prostomium epilobous (Fig. 2 A). First dorsal pore on 12 / 13. Clitellum annular at XIV – XVI; setae or dorsal pores and intersegmental furrow absent. Setal arrangement perichaetine; setae number 36 – 40 (V), 52 – 65 (VII), and 55 – 72 (VIII). Female pore single in medio-ventral at XIV (Fig. 2 B). Spermathecal pores three pairs, 5 / 6 – 7 / 8, ventro-lateral, 0.28 – 0.30 C apart ventrally. Pre-clitellar genital markings absent (Fig. 2 D). Male pores and post-clitellar genital markings absent. Internal characters. Septa 4 / 5 / 6 quite thickened, 6 / 7 / 8 thin and fibrous, 8 / 9 / 10 absent, 10 / 11 / 12 / 13 thin. Gizzard within VIII – IX (Fig. 2 C). Intestine enlarged from XIV. Intestinal caeca manicate with five finger-like sacs, originating in XXVII and extending anteriorly to XX (Fig. 3 H). Last pair of hearts in XIII. Spermathecae present, three pairs in VI – VIII ampulla ovate, surface flattened and wrinkled, 1.5 – 1.8 mm long; ampulla duct long, stout, 1.1 – 1.3 mm long, with a swollen basal portion; diverticulum originating from below the swollen portion of the spermathecal duct, stalk slender with a swollen long receptacle; diverticulum longer than the main pouch (Fig. 2 E). Seminal vesicles two pairs in XI and XII, well developed. Prostate glands and accessory glands absent.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
AFE0A675E8A35B4484DA04869B5E44C6.taxon	distribution	Global distribution. Cosmopolitan / Exotic. USA (Gates 1953, 1954, 1958, 1963, 1966, 1982; Davies 1954; Reynolds 1978, 2010, 2011, 2015 a, 2015 b; Callaham et al. 2002; Görres and Melnichuk 2012; Chang et al. 2016; Görres et al. 2017; Chang et al. 2021), Canada (Reynolds 2014, 2023), Japan (Kato 1972; Minamiya 2014), South Korea (Kobayashi 1935; Song and Paik 1969, 1970 a, 1970 b, 1971, 1973; Hong and Kim 2005; Hong and Kim 2009; Blakemore 2013 a, 2013 b), North Korea (Kobayashi 1935, 1938); Russia (Shekhovtsov et al. 2018), and China (this study).	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
AFE0A675E8A35B4484DA04869B5E44C6.taxon	distribution	Distribution in China. Liaoning Province, northeast China.	en	Han, Anne Charis N., Zhao, Nannan, Aspe, Nonillon M., Nob, Christian Jay R., Zhang, Yufeng, Wu, Donghui, Zhao, Huifeng (2026): A new species of the Amynthas corticis group with support from mitogenomic data and a new record of Metaphire agrestis (Goto & Hatai, 1899) (Oligochaeta, Megascolecidae) in northeastern China. ZooKeys 1266: 231-261, DOI: 10.3897/zookeys.1266.161903
