Balantoides minimus ( Lethiers, 1970 )

Maillet, Sebastien, Milhau, Bruno, Vreulx, Michel & Posada, Luis-Carlos Sánchez De, 2016, Givetian ostracods of the Candás Formation (Asturias, North-western Spain): taxonomy, stratigraphy, palaeoecology, relationship to global events and palaeogeographical implications, Zootaxa 4068 (1), pp. 1-78 : 19

Balantoides minimus ( Lethiers, 1970)

(Pl. I: Fig. 8)

1964 Pseudonodellina cf. parvula ( Polenova, 1953) ; Magne: 137, pl. 25, fig. 194. 1970 Pseudonodellina parvula minima nov. ssp.; Lethiers: 73, pl. 7, figs. 16–17. 1971a Aechminella minima (Lethiers) ; Becker: 27–28, pl. 3, fig. 29. 1985 Aechminella minima (Lethiers) ; Lethiers et al.: 74–75, pl. 12, fig. 1. 2008a Balantoides cf. minima (Lethiers) ; Casier & Olempska: 54, pl. 1, fig. 8. 2009 Balantoides minimus (Lethiers) ; Casier in Casier & Préat: pl. 4, figs. 9–10. 2010 Balantoides minimus (Lethiers) ; Maillet: 40, pl. 1, figs. 25–26. 2013 Balantoides minimus (Lethiers) ; Maillet: 52, pl. V, figs. 15–16. 2013b Balantoides minimus (Lethiers) ; Maillet et al.: fig. 5D.

Material. 5 specimens (3 C, 2 V).

Diagnosis. Lethiers (1970, p. 73).

Description. Small, slightly preplete carapace. Overlap of the larger LV over the RV pronounced ventrally, otherwise slight on the whole outline. Hmax at 1/3 posterior; Lmax slightly dorsal; Wmax about at mid-dorsal. Straight hinge line and dorsal margin. Cardinal angles of about 130°. Well rounded and regularly convex free margins. Anterior part of the carapace slightly higher than the posterior one. Long sulcus in the posterior part of both valves, extending from the dorsal to the ventral margins. Marked adductorial sulcus at mid-dorsal and slightly anterior. Two tight lobes, around this adductorial sulcus, merged into an oblique shoulder, prominent over the dorsal margin. Surface smooth (?).

Discussion. These specimens look like B. brauni ( Becker, 1968) . However, despite their bad preservation, the size of the carapace is smaller, a little more elongate and more asymmetrical than in B. brauni and lobes are also tighter and more prominent dorsally.

Occurrence. Upper Givetian to Lower Frasnian (Fromelennes Fm, Fort Hulobiet Mb, and Presles Fm), Ardenne (Flohimont, Cul d’Houille, Nismes, Frasnes and Aisemont sections), Middle Givetian (Candás Fm, mb C), Asturias (Peran-Perlora section); Upper Givetian to Lower Frasnian (Beaulieu Fm), Boulonnais.