Witchellia minima ( Hiltermann, 1939 )

Sandoval, José, 2022, Sonniniidae Ammonitina, Middle Jurassic from Southern Spain: taxonomic, biostratigraphical and palaeobiogeographical analysis, Geodiversitas 44 (27), pp. 801-851 : 838

Witchellia minima ( Hiltermann, 1939) [m] ( Fig. 14J )

Sonninia deltafalcata minima Hiltermann, 1939: 174 , pl. 12, figs 4, 6.

Sonninia (Poecilomorphus) boweri minima – Huf 1968: 50, pl. 4, figs 4(LT refigured)-6.

Pelekodites minimus – Morton 1975: 66, pl. 10, figs 23, 24, 31-34.

Maceratites minimus – Fernández-López 1985: 104, pl. 11, fig. 16.

? Pelekodites aff. minimus [m] – Dietze et al. 2007: 6, fig. 4c.

MATERIAL EXAMINED. — JAC22.26.2 and JAC22.43.26 .

MEASUREMENTS. — See Table 23.

DESCRIPTION

Small evolute microconch with slightly compressed ovate whorl section, rounded umbilical edge and barely convex flanks, as well as a rounded venter with a faint keel. It is scarcely ornamented with smooth inner whorls; intermediate whorls have barely visible irregular sigmoid ribs, some bifurcating near the umbilical edge. The outer whorls are smooth or almost so. The peristome has spatulate lappets and a small ventral rostrum. The septal suture is not preserved in the Subbetic specimen.

REMARKS W. macer is the most similar species to W. minima , but it is somewhat larger and has a more marked ribbing. In the Subbetic, both taxa appear at equivalent stratigraphic levels. W.minima may represent an extreme morphotype of W. macer .

DISTRIBUTION

In Scotland, W. minima occurs in the Laeviuscula and Propinquans? zones ( Morton 1975). Dietze et al. (2007) cited “ P.” aff. minimus in the Ovale Zone of Dundry Hill, Somerset (SW England). In the Iberian range ( Spain), the species is present in the Ovale and Laeviuscula zones (Fernández-López 1985) and in the Atlas (Morocco) it occurs in the Laeviuscula Zone ( Sadki 1996). The Subbetic specimens are from the Laeviuscula Zone of JAC22 section, Sierra de Alta Coloma area (Jaén Province).

Figures

FIG. 14. — A-E, Witchellia peleka (Buckman, 1923) [m]: A, TT.76.1, Ovale? Zone, Sierra de Alta Coloma;B, JA13.34.2,Ovale Zone, Sierra de Alta Coloma (JAC13 section); C, JAQ1.(-15).1, Ovale Zone, Barranco de Agua Larga (JAQ1 section); D, JSP1, Ovale Zone, Sierra de San Pedro, Jaén province; E, MOD.R.1, Ovale Zone?, Montillana, (MOD section); F-I, Witchellia macer (Buckman, 1889) [m]; F, FAa.4.1, Laeviuscula Zone?, Sierra de Alta Coloma área; G, JVM.42, bed with ammonite of the Laeviuscula and Propinquans zones, La Martinica section; H, JST.93.6, Laeviuscula Zone, Sierra del Trigo, Jaén province; I, JAC22.49.1, Laeviuscula Subzone, Sierra de Alta Coloma (JAC22 section); J, Witchellia minima (Hiltermann, 1939) [m], JAC22.43.26, Laeviuscula Zone, Trigonalis Subzone, Sierra de Alta Coloma (JAC22 section); K-O, Witchellia moisyi (Brasil, 1893) [m]; K, JAC11.6?.7, Laeviuscula Zone?, Sierra de Alta Coloma, (JAC11 section); L, M, JAC6.R.14, JAC6.R.7, Propinquans Zone, Sierra de Alta Coloma área, (JAC6 section); N, O, JAQ1.67.2, JAQ1.67.1, Propinquans Zone, Barranco de Agua Larga (JAQ1 section);P, Q, Dorsetensia liostraca Buckman,1892 [M], JGa8.32.4,JGa8.32.2,Humphriesianum Zone,Romani Subzone,Sierra de Gaena (sections, JGa2);R, S, Dorsetensia hebridica Morton,1972 [M];R, JAC3.118.4,Propinquans Zone,Hebridica Subzone,Sierra de Alta Coloma (JAC3 section);S, JAC3’.22.44,