Brachyopoidea

Nonsrirach, Thanit, Manitkoon, Sita & Lauprasert, Komsorn, 2021, First occurrence of brachyopid temnospondyls in Southeast Asia and review of the Mesozoic amphibians from Thailand, Fossil Record 24 (1), pp. 33-47 : 40

Brachyopoidea indet.

Reference material

KS37-8 ( Fig. 3m –p ), intercentrum.

Formation/age

Phu Kradung Formation (Upper Jurassic).

Locality and sediment

KS37-8 was collected at the Khao Wong locality in Khao Wong District , Kalasin Province. Sediments in this locality are grey to green siltstones .

Description

KS37-8 is a wedge-shaped intercentrum with the dorsal edge much shorter than the ventral edge. The parapophyses are close to the posterodorsal margin on the lateral surface. Both anterior and posterior surfaces are concave and show a marked circular notochordal canal, which is visible as a circular pit. The pleurocentra are reduced or absent. This intercentrum KS37-8 probably belongs to Brachyopoidea since it is the only Stereospondyli superfamily retrieved beyond the Triassic ( Buffetaut et al., 1994b). Furthermore, the wedge-shaped morphology of KS37-8 resembles the intercentra of the Brachyopoidea ( Shishkin, 1991; Warren et al., 1997; Warren and Dammiani, 1999; Warren et al., 2011), which are similar to the intercentra discovered from the Indochina block ( TF 3144) and Sibumasu blocks ( TF 3328 and TF 3329) of Thailand ( Buffetaut et al., 1994a, c). However, the intercentrum is not sufficiently diagnostic for identification at the family level.

Figures

Figure 3. Thai Brachyopoidea indet. intercentra, TF 3228 (a–d), TF 31229 (e–h), TF 3144 (i–l, after Buffetaut et al., 1994b; fig. 1), and KS37-8 (m–p). Thai Brachyopidae indet. intercentra, KS34-1474 (q–t) and KS34-1489 (u–x). Anterior views (a, e, i, m, q, u), posterior views (b, f, j, n, r, v), left views (c, g, k, o, s, w), and right views (d, h, l, p, t, x).