Trachydomia cf. nodosum ( Meek & Worthen, 1866 )

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 : 31

Trachydomia cf. nodosum ( Meek & Worthen, 1866)

( Fig. 21 E–F)

cf. Trachydomia nodosum ( Meek & Worthen, 1866) ; Knight 1933: 383, pl. 45, fig. 2a–i.

Material. One specimen: ESKU-19- LP 92.

Dimensions (mm): ESKU-19- LP 92: height = c. 2.9; width = 3.2.

Remarks. The single specimen at hand represents has the general characteristics of the genus Trachydomia . It is naticiform, ornamented with distinct nodes on whorl face and has a rather deep suture. It seems to resemble Trachydomia nodusum ( Meek & Worthen, 1866) as illustrated by Knight (1933 b) from the Pennsylvanian of the U.S.A. This specimen can be differentiated from T. cf. dussaulti as described above in having coarser and denser nodes, an impressed suture, a subsutural ramp and a distinctly broader body whorl. The present specimen is too poorly preserved for a safe identification.

Figures

FIGURE 21. A–D, Trachydomia suwanneeae sp. nov., ESKU-19-LP 26, holotype. E–F, Trachydomia cf. nodusum (Meek & Worthen, 1866), ESKU-19-LP 92. G–K, Trachyspira eleganta sp. nov., ESKU-19-LP 28, holotype. Scale bars represent: 2 mm (A–D, G–K); 1 mm (E–F).