Bellerophon, de Montfort, 1808

Ketwetsuriya, Chatchalerm, Karapunar, Baran, Charoentitirat, Thasinee & Nützel, Al- Exander, 2020, Middle Permian (Roadian) gastropods from the Khao Khad Formation, Central Thailand: Implications for palaeogeography of the Indochina Terrane, Zootaxa 4766 (1), pp. 1-47 : 10

Bellerophon sp.

( Fig. 6 H–J)

Material. ESKU-19- LP 58.

Dimensions (mm): ESKU-19- LP 58: height = 13.3; width (half) = 6.6; thickness = 12.1.

Remarks. A single anomphalous bellerophontiform shell and a fragment show strengthened, thread-like growth lines and a distinct selenizone with slightly straight short lunulae, which are the general characteristics of the genus Bellerophon . The involute shell is slightly elongated and inflated and the whorl profile is moderately well rounded. The present specimens resemble Bellerophon jonesianus de Koninck, 1863 . The specimens assigned as B. cf. jonesianus by Mansuy (1913 a, p. 103, pl. 11, figs 1–2) from the Permian of Laos is the most similar form. The specimens assigned to B. jonesianus by Delpey (1941, p. 346, figs 21–22) from the Permian of Cambodia, by Waagen (1880, p. 135, pl. 8, figs 1–2) from the Permian of Pakistan and by Nützel & Nakazawa (2012, p. 109, fig. 8A–H) from the Permian of Japan also resemble the present specimens. The present specimens resemble B. erawanensis sp. nov. they have a more elongated shape, more distinct selenizone, stronger growth lines and wider interspaces between the thread-like growth lines.

Figures

FIGURE 6. A–G, Bellerophon erawanensis sp. nov. A–E, ESKU-19-LP 55, holotype; E, shell showing V-shaped slit at crest. F, ESKU-19-LP 54, paratype; shell showing growth lines and position of selenizone. G, ESKU-19-LP 56, paratype. H–J, Bellerophon sp. H–I, ESKU-19-LP 58. J, ESKU-19-LP 59, shell fragment showing growth lines and position of selenizone. All scale bars represent 2 mm.