Ansella jemtlandica ( Löfgren, 1978 )

Zhen, Yong Yi, 2011, Middle to Late Ordovician (Darriwilian-Sandbian) Conodonts from the Dawangou Section, Kalpin Area of the Tarim Basin, Northwestern China, Records of the Australian Museum 63 (3), pp. 203-266 : 214

publication ID	https://doi.org/ 10.3853/j.0067-1975.63.2011.1586
persistent identifier	https://treatment.plazi.org/id/03CCEB77-FFDB-6379-FF9F-FA8F97ABFCB0
treatment provided by	Felipe
scientific name	Ansella jemtlandica ( Löfgren, 1978 )
status

Treatment

Ansella jemtlandica ( Löfgren, 1978)

Fig. 4A–O View Figure 4

Roundya n. nov. Sweet & Bergström, 1962: 1244–1245, text-fig. 5.

Belodella jemtlandica Löfgren, 1978: 46 , pl. 15, figs 1–8, fig. 24A–D; An et al., 1983: 77, pl. 25, figs 8–12; Zhao et al., 1984: 210, pl. 90, figs 1, 4, 11, 14; An & Zheng, 1990: pl. 10, figs 4–7.

Belodella ? jemtlandica (Löfgren) .–Ding et al. in Wang, 1993: 165, pl. 30, figs 9, 11, 14, 19.

Ansella jemtlandica (Löfgren) .–Fåhraeus & Hunter, 1985: 1173, pl. 1, figs 1–5, 9, pl. 2, fig. 12, Fig. 1 View Figure 1 (cum syn.); Ding, 1987: pl. 5, figs 11–12; Ni & Li, 1987: 396, pl. 60, figs 21–22, 24–25; An & Zheng, 1990: pl. 10, figs 4–7; Gao, 1991: 128, pl. 11, figs 3–6; Pohler, 1994: pl. 1, figs 15–16; Lehnert, 1995: 70, pl. 9, figs 1, 2, 5; pl. 10, fig. 8, pl. 12, fig. 1, pl. 13, fig. 1; Albanesi in Albanesi et al., 1998:160–161, pl. 1, figs 18–23, text-fig. 27; Zhang, 1998c: 50, pl. 1, figs 5–9; Zhao et al., 2000: 188, pl. 35, figs 13, 14; Rasmussen, 2001: 51, pl. 1, figs 4–9; Wang & Qi, 2001: pl. 1, figs 10, 12; Pyle & Barnes, 2002: 57, pl. 19, figs 1, 2; Pyle & Barnes, 2003: fig. 11.1–11.4; Zhen & Percival, 2004a: 84–86, fig. 5A–Q (cum syn.); Zhen & Percival, 2004b: fig. 4A–G; Zhen et al., 2009b: 32, fig. 2A–I; Bauer, 2010: pl. 1, figs 1–2, 4–5.

Material. 114 specimens from six samples of the Dawangou Formation (see Table 1).

Remarks. Several species of Ansella introduced in the Chinese literature, including A. fenxiangensis (An, Du, Gao, Chen & Li, 1981) = Belodella guniutanensis Ni in Ni & Li, 1987, A. longicuspica Zhang, 1998c , A. rigida (An in An et al., 1983) and A. baotaensis Ni in Ni & Li, 1987, show close morphological similarities to A. jemtlandica . They were differentiated from the latter mainly based on the depth of the basal cavities in the P elements ( An et al., 1983, p. 78; Zhang, 1998c, text-fig. 25). Zhang (1998c) suggested a possible evolutionary lineage from oldest A. longicuspica with a shallower basal cavity (about half of the P element length) to intermediate A. jemtlandica (basal cavity about three-fourths of the P element length), and then to the most derived Ansella fenxiangensis (see Fig. 5A–C View Figure 5 ) with a deep basal cavity (four-fifths to five-sixths of total P element length). Although in theory, recognition of these species with their shorter stratigraphical ranges might be more useful than a broad concept of the long ranging A. jemtlandica , in practice it may be difficult to correctly assign the material to a species based solely on the depth of the basal cavity in the P elements.

Kingdom	Animalia
Phylum	Chordata
Class	Conodonta
Order	Conodontophorida
Family	Ansellidae
Genus	Ansella