taxonID	type	description	language	source
8E0B87875A342958FC983BD7DEB2F97E.taxon	materials_examined	Type species: Desmochitina bursa Taugourdeau & de Jekhowsky, 1960	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A342958FC983B77DFDCFA7E.taxon	description	Subfamily: Desmochitininae Paris, 1981	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A36295BFC983867DA9FFAB7.taxon	materials_examined	Material: Systematic study was performed based on 31 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A36295BFC983867DA9FFAB7.taxon	description	Description: Small specimens with square-like or conical vesicle, its length is 53 – 84 μm. Some specimens’ length is slightly less than width, the L / Dp ratio is 0.79 – 1.18, and the Dp / Dc ratio is 1.07 – 1.30. Its chamber (with slightly convex flanks) gradually transitions into the aperture, and the chamber wall is reduced to form a very short membranous collar at the distal aperture, where it may preserve a round-shaped operculum. Tere is no flexure or neck observed. Te base is convex and with an evagination. Tere is a short and papillary mucron, with an orifice in the center of the base. Its chamber wall is smooth. Te specimens can be preserved as a chain or single individual. Connected individuals link with each other by mutual operculum and basal region. Measurements: Measured data based on 15 specimens. Comparison and remarks: Smooth wall surface and conical vesicle are the main morphological features of Bursachitina (Armstrong & Brasier, 2005; Paris et al., 1999). According to Zaslavskaya (1983), B. rectangularis occurs in isolation rather than in chains. However, Bursachitina sp. 1 can be preserved as a chain. Besides, the total length of B. rectangularis is larger than its chamber width (Geng et al., 1997), which is different from Bursachitina sp. 1 because the total length of Bursachitina sp. 1 may be less than its chamber width. Some reported species are also different from Bursachitina sp. 1, including Bursachitina baqaensis (Paris et al., 2015), Bursachitina nestorae (Mullins & Loydell, 2001) and Bursachitina sp. A (Mullins & Loydell, 2001). Compared with Bursachitina sp. 1, the vesicle of flattened B. baqaensis is conical (with a reduced aperture), and the morphology of B. nestorae and Bursachitina sp. A is more slender. Locality and stratigraphic horizon: Te Shenxuanyi Member of Majia section.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A37295BFF223B0CDFE5FDF7.taxon	materials_examined	Material: Systematic study was performed based on three photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A37295BFF223B0CDFE5FDF7.taxon	description	Description: All specimens are flattened, with a short columnar or conical vesicle. Te body flanks are slightly concave, basal margin and base are rounded, and no mucron is observed in the center of the basal region. Te flexure is weak or absent. Te aperture is broken. Te chamber wall surface is smooth. Measurements: Measured data based on three specimens. Comparison and remarks: Its morphology is partially consistent with the features of Bursachitina stated by Armstrong and Brasier (2005) and Paris et al. (1999). It is very similar to the Bursachitina sp. from the Telychian of Latvia reported by Loydell et al. (2010). Since its basal region’s features are unclear, and it is different from the typical Bursachitina without flexure by having a very weak flexure, this study tentatively assigned it to Bursachitina (?) sp. 1. It is also different from the Conochitina. According to Paris et al. (1999), Conochitina with a mucron in the centre of the basal region, but Bursachitina (?) sp. 1 does not observe the mucron. Locality and stratigraphic horizon: Te lower Shenxuanyi Member of Majia section.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A37295BFC983C8CDE63FCB7.taxon	materials_examined	Type species: Eisenackitina castor Jansonius, 1964	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A372944FC983D0CDF8DFD37.taxon	description	2001 Eisenackitina causiata Verniers, Mullins and Loydell, p. 745, pl. 4, figs. 1 – 6, 9. 2002 Eisenackitina causiata Verniers, Nestor and Nestor, p. 75, pl. 1, fig. 9. 2002 Eisenackitina causiata Verniers, Verniers et al., p. 294, pl. 1, fig. 12. 2002 Eisenackitina causiata Verniers, Mullins and Loydell, p. 92, figs. 3, (i & j). 2003 Eisenackitina causiata Verniers, Loydell et al., p. 224, fig. 16, (w). 2004 Eisenackitina causiata Verniers, Mullins and Aldridge, p. 755, pl. 1, figs. 1 – 4. 2005 Eisenackitina causiata Verniers, Loydell and Nestor, p. 373, fig. 4 (j). 2006 Eisenackitina causiata Verniers, Hints et al., p. 136, pl. 1, fig. 5. 2010 Eisenackitina causiata Verniers, Loydell et al., p. 271, fig. 13, (d). 2015 Eisenackitina causiata Verniers, Mӓnnik et al., p. 233, fig. 6 (I). 2018 Eisenackitina causiata Verniers, Chen et al., p. 1265, figs. 4 (2, 7). 2021 Eisenackitina causiata Verniers, Li et al., p. 12, pl. V, figs. 13 – 14.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A372944FC983D0CDF8DFD37.taxon	materials_examined	Material: Systematic study was performed based on 53 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A372944FC983D0CDF8DFD37.taxon	description	Description: Te vesicle is conical, the body length is slightly larger than its chamber width, with a L value and a L / Dp ratio of 67 – 128 μm and 1.09 – 1.55, respectively. Te flexure and neck are absent. Te body flanks are slightly convex, transitioning directly into a very short membranous collar at the aperture. Dp / Dc ratio is 1.11 – 1.43. A coin-shaped operculum may be preserved, while its detail cannot be observed. Te basal region is inflexed or protrudes toward the aboral pole, but the detail of the basal scar is unclear. Te basal margin and basal region are transitional, and the basal margin is rounded. Te vesicle surface is densely covered with short spines, and the length of the spines is usually less than 1 μm. Measurements: Measured data based on 28 specimens. Comparison and remarks: Eisenackitina causiata Verniers, 1999 is a key element in the Telychian. Its vesicle surface is irregularly covered by verrucate ornaments (Verniers, 1999). Tese specimens were also reported by Loydell and Nestor (2005), Loydell et al., (2003, 2010), Mӓnnik et al. (2015), Mullins and Loydell (2002), and Nestor and Nestor (2002) in the West Europe, all of them with conical vesicle and densely covered by verrucate ornaments, and consistent with the specimen obtained in this study. While fewer specimens with thicker verrucate ornaments were reported by Hints et al. (2006), Mullins and Loydell (2001), and Verniers et al. (2002). Compared to E. causiata, Eisenackitina dolioliformis Umnova, 1976 has a protruding mucron, Eisenackitina ripae Soufiane & Achab, 2000 is slender, and Eisenackitina spongiosa Swire, 1990 is covered by spongy ornaments. Terefore, they are different from E. causiata. Locality and stratigraphic horizon: E. causiata is abundant in the middle and upper Telychian (e. g., Loydell & Nestor, 2005; Loydell et al., 2003, 2010; Männik et al., 2015; Nestor & Nestor, 2002). It even extends into the Sheinwoodian in the West of Europe (e. g., Hints et al., 2006; Mullins & Aldridge, 2004; Mullins & Loydell, 2001, 2002). It was reported from the Tarannon Shales Formation of Banwy River and Buttington Brick Pit sections, Wales (Mullins & Loydell, 2001, 2002), the Purple Shales and Buildwas formations of Shropshire, England (Mullins & Aldridge, 2004), the Jūrmala (Loydell & Nestor, 2005; Loydell et al., 2003) and Rumba (Nestor & Nestor, 2002) formations and Adavere-Jaani stages (Loydell et al., 2010) of Latvia, the Rumba and Velise formations of Estonia (Hints et al., 2006), the Petit Roeulx, Corroy and Fallais formations of Ronquières-Monstreux region, Belgium (Verniers et al., 2002), and the Adavere stage of Sweden (Mӓnnik et al., 2015). In the Yangtze Platform, it was reported from the Telychian Shamao Formation of western Hubei Province by Chen et al. (2018) and Li et al. (2021). In this study, it was found from the lower Shenxuanyi Member of the Majia section.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A282945FC983C8DD82AFCD7.taxon	description	1997 Eisenackitina rimosa Umnova, Geng et al., p. 53, pl. 2, figs. 7 – 9. p. 54, pl. 3, figs. 5 – 6 & 9 – 10. 2021 Eisenackitina rimosa Umnova, Li et al., p. 10, pl. III, figs. 16 – 17.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A282945FC983C8DD82AFCD7.taxon	materials_examined	Material: Systematic study was performed based on eight photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A282945FC983C8DD82AFCD7.taxon	description	Description: Te vesicle is sub-conical. All the specimens are flattened, with a body length of 66.9 – 88.13 μm, a L / Dp ratio of 1.03 – 1.14, and a Dp / Dc ratio of 1.10 – 1.31. Te flanks are slightly convex, the chamber transitions directly into the aperture, no flexure, shoulder, or neck are observed. Tere is a very short, circular and serrated membranous collar at the end of the aperture. Te basal margin is blunt, or broadly rounded. Te basal region is always inflexed so that no more details of the basal scar are observed. Te vesicle is covered with dense verrucate ornaments. Te spacing between the ornaments is usually less than 1 μm, and usually becomes slightly sparse near the aperture. Measurements: Measured data based on eight specimens. Comparison and remarks: Geng et al. (1997) discussed the morphological features of E. rimosa in detail. Its conical vesicle (with a length of 119 μm, and a L / Dp ratio of 1.3) has a short membranous collar. Tere are no flexures, necks, and shoulders observed. Te vesicle surface is covered with granular ornaments. A circular and wide basal scar (10 μm in diameter) is located at the center of the base. Te morphological features of our specimens are consistent with the statement of Geng et al. (1997).	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A292945FF223DADDEB3FAB7.taxon	description	Fig. 5 A, B) 1982 Eisenackitina venusta sp. nov., Tsejelnju, p. 40, pl. 3, fig. 3. 1997 Eisenackitina venusta Tsejelnju, Geng et al., p. 54, pl. 2, figs. 1 – 5. p. 55, pl. 3, fig. 7 2023 Eisenackitina venusta Tsejelnju, Rong et al., p. 58, figs. 8 (3 – 5).	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A292945FF223DADDEB3FAB7.taxon	materials_examined	Material: Systematic study was performed based on 11 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A292945FF223DADDEB3FAB7.taxon	description	Description: Most of our specimens are fully flattened. Te vesicle (longer than wider, 67 – 87 μm long, and 60 – 83 μm wide) is conical or sub-conical, with relatively straight flanks. Te chamber is slightly constricted near the aperture so that there is a weak shrink between the membranous collar and the chamber. Te serrated collar expands and everts distally, with a length of about 5 μm. Te basal margin is blunt or broadly rounded. Te basal region of some specimens is inflexed. While some specimens have an outward base, it could be observed that the basal mucron is a small concentric pit. Te vesicle surface is covered by closely spaced and irregular miniature verrucate ornaments, and the interval of size is 1 μm. Near the collar and the basal center, the ornaments are significantly diminished. Measurements: Measured data based on 11 specimens. Comparison and remarks: In the Yangtze Platform, the E. venusta was firstly found by Geng et al. (1997). According to Geng et al. (1997) and Wang et al. (2020), E. venusta (97 μm long and 92 μm wide) has a flared and everted collar at the aperture, a truncated conical mucron at the basal center, and is covered by dense granular ornaments on the vesicle surface. Te specimens in this study and reported by Geng et al. (1997) and Wang et al. (2020) are consistent. Even though the ornamentation may not be correct for the genus, due to previous authors considering the same features for the species, the same characteristics are considered herein.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2946FC983A6DD8E2FB57.taxon	materials_examined	Type species: Conochitina micracantha subsp. robusta Eisenack, 1959	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2946FF22388DD9F8F8B7.taxon	materials_examined	Type species: Conochitina claviformis Eisenack, 1931	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2946FF22390DD8DEFC57.taxon	materials_examined	Material: One flattened and incomplete specimen.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2946FF22390DD8DEFC57.taxon	description	Description: Te smooth chamber is short columnar and gradually transitions into the aperture. Flanks are slightly convex. Tere are no shoulder, flexure and neck. Te aperture is broken. Te basal region is folded, so that the basal scar cannot be observed. Te surface of the wall is smooth, without any ornaments observed here. Measurements: Measured data based on one specimen. Comparison and remarks: Te columnar chamber is consistent with the morphological features of Conochitina (Eisenack, 1931). Since the feature of basal mucron is unknown, it is assigned to Conochitina (?) sp. 1 tentatively. Bursachitina rectangularis (Zaslavskaya, 1983) and Conochitina longa Zaslavskaya, 1983 were recorded in the Yangtze region by Geng et al. (1997). While, B. rectangularis differs from C. (?) sp. 1 by a membranous collarette at the aperture, and C. longa is narrower than C. (?) sp. 1. Locality and stratigraphic horizon: Unit 9 (lower Chejiaba Formation) of Majia section, Guangyuan, North Sichuan Province.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2946FF22382DD964F937.taxon	description	Subfamily: Conochitininae Paris, 1981	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2947FC983B2CDBC3FCB7.taxon	materials_examined	Material: One flattened specimen.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2A2947FC983B2CDBC3FCB7.taxon	description	Description: Te specimen is incomplete. Te chamber is long-columnar. Tere are no shoulder, flexure, and neck. Te aperture and the base are broken, and the base is covered by debris. Te ornaments on the wall surface are short spines, and the interval of size between the spines is about 0.5 μm. Measurements: Measured data based on one specimen. Comparison and remarks: Te long columnar chamber and short spiny ornaments indicate that it can be assigned to Belonechitina. Although Belonechitina cavei Mullins & Loydell, 2001, Belonechitina parvispinata Soufiane & Achab, 2000, Belonechitina postrobusta Nestor, 1980 and Belonechitina sp. 1 all have long columnar chamber, they are different taxa. Te most evident difference between Belonechitina sp. 1, Be. cavei and Be. parvispinata is the ornamentation. Te ornaments of Be. cavei and Be. parvispinata are irregular ridges and grana (Loydell et al., 2010; Mullins & Loydell, 2001, 2002) and multirooted (λ-like) spines, respectively. But the ornaments of Be. sp. 1 are short spines. Although the specimen we obtain here is similar to Be. postrobusta reported by Geng et al. (1997), Grahn (2006), Loydell et al., (2003, 2010), Männik et al. (2015), Nestor (2012), Soufiane and Achab (2000), and Verniers et al. (1995), the specimen is poorly preserved and more morphological features are unknown. Terefore, we tentatively assign it to Belonechitina sp. 1. Locality and stratigraphic horizon: Unit 8 (the uppermost part of the Shenxuanyi Member) of the Majia section.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2B2947FF223D0DD945F917.taxon	materials_examined	Material: One flattened and incomplete specimen.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2B2947FF223D0DD945F917.taxon	description	Description: Te specimen with a short columnar chamber. Te flanks are convex. Tere are no shoulder, flexure, and neck. Te aperture is broken, and the base is round and squashed. Te wall surface is covered by short spiny ornaments. Measurements: Measured data based on one specimen. Comparison and remarks: Belonechitina without flexure and neck, its chamber is conical, gradually transitions into the aperture, and the surface is ornamented with short spines (Jansonius, 1970). Although Belonechitina sp. 2, Belonechitina aspera Nestor, 1980 reported by Butcher (2009), Loydell et al., (2003, 2010), Männik et al. (2015), and Nestor (1994), and Belonechitina filose Geng et al., 1997 reported by Geng et al. (1997) all have conical chambers, the present study considers them to be different taxa. Te base of Belonechitina sp. 2 is round and convex, while the others are blunt. Due to the specimen we obtained is incomplete, the present study tentatively assigns it to Belonechitina sp. 2. Locality and stratigraphic horizon: Specimen was found from the Unit 2 of the Majia section.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2B2947FF2238EDD94EF897.taxon	description	Subfamily: Lagenochitininae Paris, 1981	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2B2947FF22396DDEB3FED7.taxon	materials_examined	Type species: Lagenochitina sphaerocephala Eisenack, 1932	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2C2940FF223CEDDEB3FCB7.taxon	description	2020 Angochitina bipedata Geng et al., Wang et al., p. 120, pl. 7 – 30, figs. 10 – 12.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2C2940FF223CEDDEB3FCB7.taxon	materials_examined	Material: Systematic study was performed based on 35 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2C2940FF223CEDDEB3FCB7.taxon	description	Description: Tis taxon has a total length of 105 – 161 μm and a chamber diameter of 60 – 85 μm. Its chamber is cono-spheroidal, with convex flanks, rounded margin and base. Te shoulder is absent or inconspicuous. Te flexure between the neck and the chamber is marked. Te neck is short and cone-shaped, widest near the flexure and narrowing toward the oral pole. However, unlike the neck, the long membranous collar (which can reach 10 μm long), widens toward the oral pole. Except for the collar, the vesicle surface is densely covered with spines. Tese spines are spaced about 3 μm apart. Te spines on the surface of the chamber are wider, with a length of up to 5 μm. Te spines on the neck become thinner, shorter, and disappear at the collar. Most of the spines are bi-rooted. Te distance between the two roots is very short, and no more than 1 μm. A few spines with very short distances between the two roots make it appear to be one-rooted. Measurements: Measured data based on 15 specimens. Comparison and remarks: Although its morphology looks like Angochitina sinica Cramer, 1970, they are different species. A. sinica found in the Yangtze Platform is covered by simple spines (Geng et al., 1997). While the λ-shaped spines on the vesicle surface is the diagnostic feature of this taxon (Wang et al., 2020). Although Paris et al. (1999) regarded Lambdachitina (Lakova, 1986) as a synonym of Angochitina (Eisenack, 1931), based on the unique spines of this taxon, Geng et al. (1997) and Huang et al. (2017) still classified them as Lambdachitina. Te current study supports the view of Paris et al. (1999) and assigs it to Angochitina. Some of our specimens are slightly smaller than those reported by Geng et al. (1997), but their morphological diagnostic features are consistent, and therefore they are the same species. Locality and stratigraphic horizon: Previous reports indicate that this species has only been found in the Telychian Xiushan Formation of western Hunan Province. In this study, four hundred and fifteen specimens were recorded from the Shenxuanyi Member.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2C2940FF223C6DD994FD17.taxon	materials_examined	Type species: Angochitina echinata Eisenack, 1931	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2D2942FC983CACDEB2FB96.taxon	description	1974 Angochitina longicollis Eisenack, Laufeld et al., p. 56, figs. 19 (A – C). 1985 Angochitina longicollis Eisenack, Li and Geng, p. 603, pl. I, figs. 1 – 19. P. 605, pl. II, figs. 1 – 6, 8. p. 607, pl. III, figs. 5 – 9. 1988 Angochitina longicollis Eisenack, Geng and Cai, p. 256, pl. I, fig. 3. 1994 Angochitina longicollis Eisenack, Nestor, p. 179, pl. 7, figs. 1 – 4. 1995 Angochitina longicollis Eisenack, Verniers et al., p. 658, figs. 5 (m – n). 1996 Angochitina longicollis Eisenack, Chen, p. 69, pl. II, figs. 5 – 10. 1997 Angochitina longicollis Eisenack, Geng et al., p. 163, pl. 11, figs. 2 – 10. 2001 Angochitina longicollis Eisenack, Mullins and Loydell, p. 737, pl. 3, figs. 1 – 8. 2002 Angochitina longicollis Eisenack, Mullins and Loydell, p. 92, fig. 3 (r). 2003 Angochitina longicollis Eisenack, Loydell et al., p. 224, figs. 16 (X). 2004 Angochitina longicollis Eisenack, Mullins and Aldridge, p. 759, pl. 3, figs. 3, 5. 2005 Angochitina longicollis Eisenack, Loydell and Nestor, p. 373, fig. 4 (d). 2006? Angochitina longicollis Eisenack, Hints et al., p. 136, pl. I, fig. 24. 2010 Angochitina longicollis Eisenack, Loydell et al., p. 271, figs. 13 (h). 2012 Angochitina longicollis Eisenack, Nestor, p. 246, fig. 4 (k). 2015 Angochitina longicollis Eisenack, Männik et al., p. 233, fig. 6 (H). 2015 Angochitina longicollis Eisenack, Tang et al., p. 224, figs. 3 (C – I). 2021 Angochitina longicollis Eisenack, Li et al., p. 11, pl. IV, fig. 1.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2D2942FC983CACDEB2FB96.taxon	materials_examined	Material: Systematic study was performed based on 217 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2D2942FC983CACDEB2FB96.taxon	description	Description: Tis chitinozoan is very slender, with a total length of 135 – 194 μm and a L / Dp ratio of about 1.34. Te chamber is cylindro-ovoid or cono-ovoid, with broad round flanks, margin, and base. Te flexure between the chamber and the neck is marked. Te columned neck (including a very shortly membranous collar) occupies more than 1 / 3 of the total length. Te spinous ornaments that cover the vesicle surface (including the basal region) are dense but become sparse near the aperture. Te spines are regular and distributed longitudinally. Broken spines indicate that these ornaments are hollow. Measurements: Measured data based on 25 specimens. Comparison and remarks: According to Eisenack (1959), A. longicollis is slender, with an ovoid chamber and a long neck, and it is covered by regular spines (Nestor, 1994). Tis species is common in the Telychian. Several specimens were found in the Yangtze Platform. According to Li and Geng (1985), its neck occupies 1 / 2 of the total length (minimum length 193.3 μm) and widens in the direction of the aperture. Geng et al. (1997) also reported some specimens (mean length 178 μm) slightly smaller than those of Li and Geng (1985). According to Geng et al. (1997), Te Dc / Dp ratio of A. longicollis was about 0.61, which was slightly larger than those reported by Li and Geng (1985). Te spines are longitudinal, and the base of the spines may be bifurcated (Geng et al., 1997). It should be noted that Mullins and Loydell (2001) reported that some specimens had surface ornaments showing membranes connecting the spines. Te size and morphological features of the specimen we obtained are consistent with those of Geng et al. (1997) and some typical specimens reported by Laufeld et al. (1974), Loydell and Nestor (2005), Nestor (2012), and Verniers et al. (1995). Terefore, they are assigned to Angochitina longicollis Eisenack, 1959. Locality and stratigraphic horizon: A. longicollis is a globally distributed species common in the middle and upper Telychian deposits of Avalonia, Baltica, Gondwana and Laurentia (Verniers et al., 1995), such as the Jūrmala Formation of Latvia (Loydell & Nestor, 2005; Loydell et al., 2010), the Adavere Formation of Sweden (Männik et al., 2015), and the Tarannon Shale Formation of Wales (Mullins & Loydell, 2001). In the Yangtze Platform, it was found in the Shamao Formation of Hubei Province (Chen, 1996; Li et al., 2021), the Xiushan Formation of Guizhou and Hunan provinces (Geng & Cai, 1988; Geng et al., 1997), the Fentou Formation of Jiangsu Province (Li & Geng, 1985), and the Shenxuanyi Member of Sichuan Province (Geng et al., 1997 and this study).	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F2943FF223D8DDE34FCB7.taxon	materials_examined	Material: One flattened specimen.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F2943FF223D8DDE34FCB7.taxon	description	Description: Its outline is slender, with a total length and a L / Dp ratio of 171 μm and 2.58, respectively. Te chamber is cono-ovoid, with convex flanks and a round margin and base. Te chamber shrinks evenly into the neck, and the neck is conical and gradually contracts distally. Te flexure between the chamber and the neck is weak. Tere is a long membranous collar (15 μm long) at the end of the aperture. Te neck length (including the collar) is approximately half of the total length. Te ornaments on the vesicle surface are discontinuous membranes, distributed longitudinally and reduced at the neck and base. Measurements: Measured data based on one specimen. Comparison and remarks: Chitinozoans covered by membranous ornaments are unusual in the Llandovery. Although the membranous ornaments of Hercochitina (Jansonius, 1964) are also arranged longitudinally (Paris et al., 1999) and exhibit good continuity (Soufiane & Achab, 2000), its conical chamber (without neck) differs from the cono-ovoid chamber (with tubular neck) of Angochitina sp. 1. Te ornaments of Ramochitina (Sommer and van Boekel, 1964) are distinct crests (vertical rows of spines or membranes) (Paris et al., 1999). In contrast, the membranous ornaments of Angochitina sp. 1 lack distinct crests, indicating they are different species. Te vesicle form of Angochitina sp. 1 is similar to A. longicollis, both of them have ovoid chamber and longer neck. But A. longicollis is mainly covered by simple and hollow spines (Laufeld, 1974; Nestor, 1994). Although in the report of Mullins and Loydell (2001), figure 7 of plate 2 shows the membrane at the base of the spinous ornaments of A. longicollis, they are different species as Angochitina sp. 1 does not have distinct crests. Te specimen we recognize appears to be a transition element of Angochitina (Eisenack, 1931) and Ramochitina (Sommer and van Boekel, 1964). Due to its vesicle form resemble that of A. longicollis, this study tentatively assigns it to Angochitina sp. 1. Locality and stratigraphic horizon: It was recognized in the uppermost of the Shenxuanyi Member.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F2943FC983D0CDFCBF8F6.taxon	materials_examined	Material: Systematic study was performed based on 17 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F2943FC983D0CDFCBF8F6.taxon	description	Description: Tis taxon with an ovoid chamber and a long column neck. Te body flanks, margin and base are rounded. Te shoulder is absent, while the flexure between the chamber and the neck is evident. Te distal end of the neck has a short membranous collar. Te vesicle surface is covered with simple spines (2 μm long). Te spines are solid, and no hollow structures are observed. Te spines are dense and randomly distributed on the surface of the chamber (the interval of size is 2 – 5 μm) but sparse on the neck. Measurements: Measured data based on nine specimens. Comparison and remarks: Te spinous ornaments of A. longicollis are hollow and ordered longitudinally (Geng et al., 1997; Laufeld, 1974; Nestor, 1994), and the neck of A. longicollis is also covered by spinous ornaments (Mullins & Loydell, 2002; Nestor, 2012; Verniers et al., 1995). But the spinous ornaments of this taxon are solid, mainly distributed on the surface of the chamber, and rarely on the surface of the neck. Terefore, although the vesicle morphology of this taxon is very similar to A. longicollis, the present study distinguishes it from A. longicollis and tentatively assigns it to Angochitina sp. 2. Locality and stratigraphic horizon: It was recognized in the Shenxuanyi Member in this study.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F294CFC98394CD94BFB17.taxon	materials_examined	Material: Systematic study was performed based on 64 flattened specimens.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A2F294CFC98394CD94BFB17.taxon	description	Description: It is a kind of slender chitinozoan with a total length of 128 – 178 μm, and a L / Dp ratio of 2.24 – 3.24. Te well-preserved specimens show that its chamber is ovoid, with convex flanks and rounded margin and base. Te flexure is marked. Te neck is columnar (up to 1 / 2 of the total length), transitions into a short membranous collar at the aperture, and some specimens with intraspecific variation show that its neck slightly expanded toward the oral pole. Te vesicle surface is covered with small, irregular, and very sparse verrucate ornaments. Te ornaments on the neck surface are significantly less than those on the chamber surface. Measurements: Measured data based on 16 specimens. Comparison and remarks: Tis taxon is distinguished from A. longicollis and Angochitina cf. paucispinosa Miller et al., 1997 by its small, sparse, and verrucate ornaments rather than spinous ornaments. Te morphology of its neck and chamber is consistent with that of Angochitina sp. 1 in this paper, but the membranous ornaments of Angochitina sp. 1 is inconsistent with its verrucate ornaments. Terefore, this study assigns it tentatively to Angochitina sp. 3. Locality and stratigraphic horizon: Herein, specimens were found from the Shenxuanyi Member.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A20294CFF223AEDD8BFFD77.taxon	materials_examined	Material: Systematic study was performed based on four photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A20294CFF223AEDD8BFFD77.taxon	description	Description: Tis chitinozoan has a total length of 151 – 161 μm and a chamber diameter of 64 – 81 μm. Te chamber (with inconspicuous shoulders) is cone-spheroidal, with a broad rounded flexure, flanks, margin, and base. Te long columnar neck usually transitions into a short membranous collar that expands at the aperture. Te vesicle surface (except at the collar) is sparsely covered with thick (width up to 1 μm), long (length up to 10 μm), and simple spinous ornaments (solid spines). Measurements: Measured data based on three specimens. Comparison and remarks: Its morphological features are consistent with Angochitina (Eisenack, 1931). A. longicollis, Angochitina caspiensis Ghavidel-syooki, 2006, Angochitina cf. echinata Eisenack, 1931, Angochitina elongate Eisenack, 1931, Angochitina fentouensis Li & Geng, 1985, Angochitina rarispinosa Geng, et al., 1997, and Angochitina sinica Cramer, 1970 have smaller spines than this taxon. Furthermore, although this taxon has similar spines to Angochitina heterotricha Geng et al., 1997, Angochitina cf. paucispinosa Miller et al., 1997, and Angochitina cf. lebaica Eisenack, 1972 b, the vesicle morphology of this taxon is significantly different from theirs. At present, no similar specimens have been reported. Terefore, in this study, it is assigned to Angochitina sp. 4 tentatively. Locality and stratigraphic horizon: Specimens assigned to this species were recognised in the lower Shenxuanyi Member.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A20294CFC983CCDDFDBF837.taxon	materials_examined	Material: Systematic study was performed based on 63 photomicrographs.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
8E0B87875A20294CFC983CCDDFDBF837.taxon	description	Description: Te ovoid chamber (shoulder is inconspicuous) with convex flanks, rounded margin and base. Te flexure between the chamber and neck is also rounded. Te neck is cylindrical, and occupies 1 / 3 of the total length. Some intraspecific variation specimens have significantly shorter necks (less than 1 / 3 of the total length). Te neck transitions into a slightly dilated membranous collar at the aperture, with a Dp / Dc ratio of 1.54 – 2.60. Te ornaments on the vesicle surface are discontinuous triangular membranes that shrink into distinct crests. Tese longitudinally arranged spines are not dense, the interval of size is 2 – 5 μm. Te ornaments near the aperture are significantly reduced. Measurements: Measured data based on 24 specimens. Comparison and remarks: Its ovoid chamber and cylindrical neck are similar to those of Angochitina cf. paucispinosa Miller et al., 1997, Angochitina echinata Eisenack, 1931, A. fentouensis, A. hansonica, A. rarispinosa, and A. longicollis, but its triangular membranous spines with marked crests are different from theirs. Although Mullins and Loydell (2001) also reported some discontinuous membranes at the base of the spines of A. longicollis, it is different from that of Angochitina sp. 6 by longer and denser spines. Besides, Angochitina sp. 1 reported in this study has denser ornaments and a narrower neck. Terefore, they are different taxa, and the current study tentatively assigns it to Angochitina sp. 5. Locality and stratigraphic horizon: Specimens were discovered from the Shenxuanyi Member.	en	Li, Yangui, Yan, Chunbo, Wang, Chuanshang, Maletz, Jörg, Liang, Yan, Yao, Huazhou, Wu, Haizhi, Chen, Weixiong, Cheng, Jingqing, Fang, Zichen, Wang, Xiaofeng (2025): Chitinozoans from the Telychian (Llandovery, Silurian) Shenxuanyi Member, upper Ningqiang Formation of the northwestern Yangtze Platform, China. Swiss Journal of Palaeontology (20) 144 (1): 1-33, DOI: 10.1186/s13358-025-00364-7, URL: https://doi.org/10.1186/s13358-025-00364-7
