Adolfia sp.

Mottequin, Bernard, 2008, New observations on Upper Devonian brachiopods from the Namur-Dinant Basin (Belgium), Geodiversitas 30 (3), pp. 455-537 : 501-502

Adolfia sp.

( Fig. 43 G-L)

MATERIAL EXAMINED. — BM-2002-7 (five articulated specimens, one ventral valve, one dorsal valve).

REMARKS Seven poorly preserved specimens of which the microornament consists of long subradial capillae with spine bases are left in open nomenclature. Th ey have been collected in the upper part of the Neuville Formation on the southeastern margin of the Dinant Synclinorium.Th ey are close to Adolfia deflexa (Roemer,1843) sensu Vandercammen and A.rarispinosa (Vandercam- shell FIG. 45 (IRScNB.— Adola fi12289 a cf. trelonensis ),loc.BM- (Le 2001 Maître -2,Lambermont,1961),almost Formation complete: men, 1955), but both species need to be revised. A, ventral view; B, dorsal view; C, lateral view; D, posterior view; E, anterior view; F, detail of micro-ornament with anterior margin to the left of the photograph. Scale bars: A-E, 10 mm; F, 1 mm.

Adolfia cf. trelonensis (Le Maître, 1961)

(Fig. 45; Table 4) MATERIAL EXAMINED. — BM-2001-2 (one articulated specimen). Gürichella trelonensis Le Maître, 1961: 115-120 , pl. 8, figs 1-14. — Vandercammen 1966: 276-279, 284, pl. 2, REMARKS figs 1-10, pl. 3, fig. 7.

Only one specimen has been recovered.It displays the Guerichella trelonensis – Sartenaer 1967: 386. following external characters: shell wider than long,

Mottequin B.

ventribiconvex, subpentagonal in outline; lateral and anterior margins outlining a curve slightly excavated medially by the sulcus; sulcus wide, well-delimited, shallow, with bottom flattened at front; tongue 1.85 times wider than high, subtrapezoidal, perpendicular to the commissural plane; ventral interarea slightly concave, (6.25)times wider than high, cata-apsacline; delthyrium not observed; dorsal valve wider than long, subtrapezoidal in outline; dorsal posterolateral areas inclined to become flat; fold originating at beak, low, clearly delimited, with top flattened; dorsal interarea not observed; 12 sharp and rounded costae per flank, separated by similar grooves;most internal costae with bifurcation; sulcus with one central and two lateral costae;fold with four costae increasing by intercalation; subcylindrical spine bases arranged along subradial alignments; growth lamellae rare. Th e specimen is close to Le Maître’s species in the bifurcations of the most internal costae on the flanks, the profile of its interarea, its shallow sulcus and low fold, as well as its transverse outline. However, it does not display rounded cardinal extremities. It originates from the base of the Lambermont Formation (northern border of the Dinant Synclinorium). Some badly preserved specimens collected in the upper part of the Aisemont Formation could be assigned to this taxon.

Figures

FIG. 43. — A-F, Adolfia biverrucosa (Vandercammen, 1955), almost complete shell (IRScNB a12285), loc. BM-2003-8, Neuville Formation; G-L, Adolfia sp., complete shell (IRScNB a12288), loc. BM-2002-7, Neuville Formation; A, G, ventral views; B, H, dorsal views; C, I, lateral views; D, J, posterior views; E, K, anterior views; F, L, detail of micro-ornament. Scale bars: A-E, G-K, 10 mm; F, L, 1 mm.