Novispathodus ex gr. abruptus ( Orchard, 1995 ), 2005

Leu, Marc, Bucher, Hugo, Vennemann, Torsten, Bagherpour, Borhan, Ji, Cheng, Brosse, Morgane & Goudemand, Nicolas, 2022, A Unitary Association-based conodont biozonation of the Smithian-Spathian boundary (Early Triassic) and associated biotic crisis from South China, Swiss Journal of Palaeontology (19) 141 (1), pp. 1-61 : 29-32

Novispathodus ex gr. abruptus ( Orchard, 1995)

Figs. 16E ; 17W, Y, Z , AE; 18H; 20A–G, K, L, M, Q, X

1981 Neospathodus homeri Bender ; Koike, pl. 1, fig. 5.

1984 Neospathodus sp. A ; Hatleberg & Clark, pl. 3, fig. 8, 21.

*1995 Neospathodus abruptus n. sp.; Orchard, p. 118, 119, figs. 3.16–3.19, 3.23–3.26.

2005 Novispathodus abruptus (Orchard) ; Orchard, p. 90, text-fig. 16.

2009 Novispathodus abruptus (Orchard) ; Orchard & Zonneveld, p. 784, fig. 15 parts 34–37.

2012a Novispathodus sp. nov. A; Goudemand & Orchard in Goudemand et al., p. 1031, figs. 2A, R?, Z?.

2012a Novispathodus sp. nov. B; Goudemand & Orchard in Goudemand et al., p. 1031, fig. 3V.

2018 Novispathodus abruptus (Orchard) ; Maekawa in Maekawa et al., p. 33, figs., 18.1–18.3, 18.20, 18.23, 18.24, 18.26, 18.27 (only).

Material.> 50 specimens.

Diagnosis. As in Orchard, 1995.

Remarks. Here we consider Nv. abruptus in a broad sense, including elements that correspond to Nv. abruptus sensu stricto together with forms that have been suggested to deserve assignment to separate species, such as Nv. sp. nov. A and Nv. sp. nov. B Goudemand and Orchard (in Goudemand et al., 2012b). We consider the most diagnostic feature of Nv. ex gr. abruptus is the terminal 1–3 progressively smaller denticles at the posterior end.

(See figure on next page.)

Te P 1 element of this species is less robust, more rectangular with more fused denticles than that of Ic. crassatus . Its morphology also recalls that of the homologous element in Nv. pingdingshanensis , but its basal cavity is relatively smaller and its denticles are not as posteriorly recurved nor usually as broad as in the latter. Te P 1 element of Tr. symmetricus has more posteriorly reclined denticles, it may have a small terminal denticle but not several of increasingly smaller size. Yet, the distinction between Tr. symmetricus and Nv. abruptus may be confusing. Te P 1 element of Tr. homeri has a more elongated basal cavity and a more developed, posteriorly reclined and laterally deflected process than in both Tr. symmetricus and Nv. abruptus . Goudemand and Orchard (in Goudemand et al., 2012b) implicitly suggested that elements like those of their Nv. sp. nov. B, where the small terminal denticles are not increasingly smaller but of equal (small) height instead, may be transitional between Nv. abruptus and Tr. homeri (compare the elements illustrated in figs. 2.9 and 3.17 of Orchard 1995, assigned to Tr. homeri and Nv. Abruptus , respectively). Note further that, based on the material from Tsoteng, it is likely that suchP 1 elements were still associated with a Novispathodus apparatus. Tis suggests that P 1 elements like that of Tr. homeri may have evolved before the more substantial modifications of the rest of the apparatus implied by the difference between Novispathodus and Triassospathodus .

Occurrence. Worldwide occurrence in latest Smithian and early Spathian rocks. Xenoceltites and Tirolites beds within Nv. pingdingshanensis and Nv. brevissimus zones, Japan ( Koike, 1981; Maekawa et al., 2018). Oman ( Orchard, 1995). British Columbia ( Orchard & Zonneveld, 2009), South China; Goudemand et al., 2012b; this study).

Figures

Fig. 16 Neogondolellinae, Novispathodinae and Mullerinae from Shanggang and Youping cascade. Magnification is ×80.The scale bar is 400 μm. All elements are considered to be P1 elements if not specifically identified otherwise. A, F, M Discretella? n. sp. C; A YC16,PIMUZ 39115; F YC16, PIMUZ 39116; M SHA342C, PIMUZ 39117. B Discretella? n. sp. B;YC16, PIMUZ 39113. C Discretella aff.discreta (MÜller);YC22,PIMUZ 39106. D, S Discretella discreta (MÜller); D YC16, PIMUZ 39110; S SHA304C, PIMUZ 39111. E Novispathodus ex gr. abruptus (Orchard);YC41, PIMUZ 39225. G–I, K, L, N, O Discretella pseudodieneri n. sp.; G YC16, PIMUZ 39124; H YC25, PIMUZ 39125; I SHA304C,PIMUZ 39126; K YC22, PIMUZ 39127,L YC25, PIMUZ 39128; N SHA304C,PIMUZ 39129; O SHA343C,PIMUZ SQL54979. J Guangxidella bransoni (MÜller);YC16, PIMUZ 39140. P–R Neospathodus bevelledi n. sp.; P SHA 304C,PIMUZ 39178; Q SHA333C, PIMUZ 39179; R YC12, PIMUZ 39180

Fig. 17 Novispathodinae from Qiakong,Laren, Shanggang,and Lilong. Magnification is × 80.The scale bar is 400 μm. All elements are considered to be P1 elements if not specifically identified otherwise. A–C, J, T, AA Novispathodus ex gr. pingdingshanensis (Zhao & Orchard);A, QIA138,PIMUZ 39226; B QIA138, PIMUZ 39227; C LAR202, PIMUZ 39228; J QIA136, PIMUZ 39229;T LIL504, PIMUZ 39230; AA LIL508,PIMUZ 39231. D–F, M–P, R, S, U, X, AB, AD Novispathodus pingdingshanensis (Zhao & Orchard); D QIA135, PIMUZ 39259; E LIL508,PIMUZ 39260; F LIL506, PIMUZ 39261; M LIL506, PIMUZ 39262; N LIL506,PIMUZ 39263; O LIL507, PIMUZ 39264; P LIL506, PIMUZ 39265; R LIL508,PIMUZ 39266; S LAR204,PIMUZ 39267; U LIL507, PIMUZ 39268; X LIL508, PIMUZ 39269; AB LIL508, PIMUZ 39270; AD LIL508, PIMUZ 39271. G, I, Q Novispathodus cf.?gryphus n. sp.; G QIA136, PIMUZ 39204; I QIA136, PIMUZ 39205; Q QIA135, PIMUZ 39206. H, K, L Novispathodus gryphus n. sp.; H QIA135, PIMUZ 39243; K LIL506, PIMUZ 39244; L LIL506,PIMUZ 39245. V Novispathodus praebrevissimus n. sp.; LIL507, PIMUZ 39273. W, Y, Z, AE Novispathodus ex gr. abruptus (Orchard); W LIL505, PIMUZ 39208; Y SHA346,PIMUZ 39209; Z LIL506, PIMUZ 39210; AE SHA346, PIMUZ 39211. AC sp. indet.; LIL504, PIMUZ 39295. AF Novispathodus pingdingshanensis (P1 cluster) (Zhao & Orchard); QIA136, PIMUZ 39272

Fig. 18 (See legend on previous page.)