Witchellia rubra (Buckman, 1926)

Sandoval, José, 2022, Sonniniidae Ammonitina, Middle Jurassic from Southern Spain: taxonomic, biostratigraphical and palaeobiogeographical analysis, Geodiversitas 44 (27), pp. 801-851 : 829-831

Witchellia rubra (Buckman, 1926) [M]

( Fig. 12 E-G)

Rubrileiites ruber Buckman, 1926 : T. A. 6, pl. 642 (HT).

Witchellia aff. rubra – Morton 1975: 56, pl. 9, figs 1-34.

Witchellia cfr. rubra – Pavia 1983: pl. 5, fig. 9.

Witchellia rubra – Fernández-López 1985: 78, text-fig. 8B, pl. 7, fig. 1. — Hernández-Molina et al. 1991: fig. 15.3.

Witchellia albida – Sandoval 1990: pl. 2, fig. 1.

non Witchellia rubra – Sandoval 1990: 146, pl. 1, fig. 7 (corresponds to Witchellia striata n. sp.).

Witchellia sp. – Dietze et al. 2005: 61, fig. 34c, f.

Witchellia cf. rubra – Chandler et al. 2006: fig. 8(3). — Dietze et al. 2007: 15, pl. 5, fig. 1.

Witchellia cf. sayni/pseudoromanoides – De Baets et al. 2008: 574, figs 5d, e.

MATERIAL EXAMINED. — JAC3.71.4 , JAC3’.4.2 , JAC3’.4.11 , JAC4.64.3 , JAC4.64.5 , JAC22.56.14 , JAC22.56.15 , JAC22.56.16 , JAC22. R.8 , JFA.15.1 and JFA.16.2.

MEASUREMENTS. — See Table 15 .

DESCRIPTION

Medium to relatively large macroconchs with rather involute coiling(U/D varying from 0.22 to 0.30), broad whorl expansion, narrow and relatively deep umbilicus. The section, subrectangular compressed on inner and intermediate whorls, becomes subtriangular in the adult BC, where the ventral region is narrow with a relatively high keel. The umbilical wall is almost vertical, the umbilical edge rounded and the flanks gently convex.Inner and intermediate whorls have weak irregular ribs, generally simple, flexuous, and subradial, with the ventral termination frequently projecting forward. The PH end, at times the intermediate whorls, and the BC are almost smooth and have no tubercles or thickening of the ribs near the umbilical border. The septal suture is simple with L wide and short.

REMARKS

The HTs of W. albida and W. rubra are remarkably alike in size, coiling, whorl section, keel, and ornamentation. Judged by these external morphological characters, the two species could be synonymous. In this case, W. rubra would have nomenclature priority because it was nominated by Buckman (1926: T.A. 6, pl. 642) and W. albida was nominated by Buckman in the same year, but in pl. 687. The only appreciable distinction is the septal suture, which is more complex in W. albida than in W. rubra . Also, the types of each species come from different faunal horizons, since W. albida is from the Ovale Zone, Bj-5 horizon ( Chandler et al. 2006), whereas the type of W. rubra is from the Laeviuscula Zone and Subzone, Bj-9 horizon ( Dietze et al. 2007).

DISTRIBUTION

The type horizon of “ Rubrileiites ” ruber is in the upper part of the Laeviuscula Zone , Laeviuscula Subzone , Bj-9 horizon ( Dietze et al. 2007). In the Iberian range ( Spain), most of the specimens are from the Laeviuscula Zone , but some specimens are reworked together with fossils from the base of the ( Sauzei ) Propinquans Zone ( Fernández-López 1985: 79). Subbetic specimens are from the upper part of the Laeviuscula Zone ( Laeviuscula Subzone ) and of the lower part of the Propinquans Zone from Sierra Alta Coloma area (section JAC3, JAC3’, JAC4, JAC22; Jaén Province ), and from Rio Fardes (section JFA; Gorafe, Granada Province).

Figures

FIG. 12. — A-D, Witchellia albida(Buckman, 1926) [M]: A, JAC11.7.5,Laeviuscula Zone,Sierra de Alta Coloma (JAC11 section); B, JAC22.35.5,Laeviuscula Zone, Trigonalis Subzone,Sierra de Alta Coloma (JAC22 section); C, JAC13.R.3,Laeviuscula Zone?, Sierra de Alta Coloma (JAC13 section); D, JAC22.R.3, Laeviuscula Zone?, Sierra de Alta Coloma (JAC22 section). E-G, Witchellia rubra (Buckman, 1926) [M]: E, JAC3.71.4, Laeviuscula Subzone, Sierra de Alta Coloma (JAC3 section); F, JAC22.R.8, Laeviuscula Zone?, Sierra de Alta Coloma (JAC11 section); G, JAC3’.4.11, Propinquans Zone, Patella Subzone, Sierra de Alta Coloma (JAC3’ section). Scale bar: 1 cm.