Glottidia cf. dumortieri ( Nyst, 1843 )

Dulai, Alfréd, 2016, Sporadic Pliocene and Pleistocene brachiopods in Naturalis Biodiversity Center (Leiden, the Netherlands): Records from the Mediterranean, and the North Sea Basin, Fragmenta Palaeontologica Hungarica 33, pp. 65-98 : 78-79

Glottidia cf. dumortieri ( Nyst, 1843)

( Figs 5–9)

1843 Lingula Dumortieri – NYST, pp. 337–338, Pl. 34, Figs 4 a-c.

1872 Lingula Dumortieri Nyst – WOOD, pp. 172–173, Pl. 11, Figs 1 a-c.

1874b Lingula Dumortieri Nyst – DAVIDSON, p. 153, Pl. 7, Figs 1–3.

1881 Lingula Dumortieri Nyst – NYST, p. 252, Pl. 28, Figs 4 a-c.

1893 Lingula Dumortieri Nyst – VINCENT, pp. 41–42.

1964 Glottidia dumortieri (Nyst) – CHUANG, pp. 155–157, Text-Fig. 1.

2004 Glottidia dumortieri (Nyst) – VOSKUIL, p. 47, Text-Fig. 1.

2013 Glottidia dumortieri (Nyst) – DULAI, pp. 25–26, Figs 6–14.

Material – Gedgrave (159 fragmentary specimens); Delden (Delden Member:> 210 fragmentary specimens; Zenderen Member:> 30 fragmentary specimens).

Remarks – Although their fossilization potential is rather low ( EMIG 1990), remains of lingulid brachiopods are common in the Miocene and Pliocene deposits of the North Sea Basin. In several cases these are the dominant fossils, as all or most of the calcium carbonate shells dissolved from the sediments. Species dumortieri was described from the Pliocene of Belgium by NYST (1843) as Lingula . This generic assumption was accepted until the mid-1960s, when CHUANG (1964) recognised that this species should be assigned to the genus Glottidia . This classification was confirmed recently by DULAI (2013) on the basis of Miocene samples from the Netherlands (Beugen). Lingula sp. was mentioned several times even recently from the North Sea Basin, but up to now, the only confirmed lingulid brachiopod is Glottidia . Lingula is known from the Miocene of the Central Paratethys ( EMIG & BITNER 2005), the Atlantic Ocean in France ( EMIG et al. 2007) and from the Mediterranean ( DREGER 1911).

The studied samples contain rather fragmentary lingulids, but some of the specimens can be identified clearly as G. dumortieri . Lingulids are especially frequent in the two boreholes (Delden and Neede), which yielded samples from the Delden and Zenderen Members of the Breda Formation. The identifiable lingulid specimens are from the Delden Member of Twickel borehole at Delden (Gelderland), while the older Zenderen Member yielded very fragmentary lingulids which were not identifiable at species level. In the case of Gelselaarsbrug borehole at Neede (Gelderland) both members of the Breda Formation contain only very fragmentary lingulids. All of the Coralline Crag samples from Gedgrave contain more or less fragmentary lingulid specimens. Species dumortieri was mentioned from the Coralline Crag as early as WOOD (1872) and he realised that it is not rare at Sutton, but all specimens are mutilated.

Glottidia ? sp.

Material – Gedgrave (24 fragments); Cricqueville-en-Bessin (2 fragments); Kreekrak (7 fragments); Delden (Delden Member: 22 fragments, Zenderen Member:> 95 fragments); Neede (Delden Member:> 124 fragments; Zenderen Member: 35 fragments).

Remarks – Several samples from the Pliocene of England, France and the Netherlands yielded indeterminable Lingulidae fragments. The small size of the fragments makes it impossible to decide whether they belong to Lingula or Glottidia . Until now, only Glottidia has surely been confirmed from the Neogene of the North Sea Basin (e.g. CHUANG 1964; DULAI 2013), therefore, Glottidia is used for these fragments with question mark.