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Leberidocysta microverrucosa

From Fensome et al., 2019:
Leberidocysta microverrucosa Slimani, 1994, p.111–112, pl.18, figs.18,21–25. Holotype: Slimani, 1994, pl.18, figs.24–25. Questionable assignment: Slimani (1994, p.111). Taxonomic junior synonyms: Hexagonifera verrucosa (name not validly published) and Leberidocysta? verrucosa, both according to Slimani (2001a, p.193). Schiøler et al. (1997, p.87) considered this species to be a possible taxonomic junior synonym of Leberidocysta? flagellichnia. Age: early Campanian–earliest Danian.

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Original description (Slimani, 1994):
Leberidocysta? microverrucosa sp. nov. (P1.18, Fig. 18,21-25)
Name derivation: Greek: micro, small; Latin: verruca, wart; reference to the warty surface of the endocyst.
Holotvpe: Turnhout -892.87 m, preparation 4, E.F. coord. X40.
Paratvpe: Turnhout -892.87 m, preparation 1, E.F. coord. E32.
Type locality: Turnhout -892.87 m.
Type horizon: Lower Maastrichtian
Synonymy:
1971: Hexagonifera chlamydata COOKSON and EISENACK, 1962b - WILSON, pl. 4, fig. 6.
1974: Hexagonifera verrucosa sp. nov. in WILSON, p. 282-283. pl. 10, fig. 12-13, text-fig. 44.
?1975: Hexagonifera sp. B - WILLIAM S and BRIDEAUX, pl. 8, fig. 5, pl. 10, fig. 1.
?1992: "Forma X sp. I" - MARHEINECKE, p. 121, pl. 27, fig. 11-13.

Diagnosis: Small cavitated cyst, with an ovoidal to subspheroidal endocyst and typically covered with microwarts; a smooth, endocyst-like or subpolyhedral pericyst has very low ridges that indicate vague paratabulation. The endophragm and periphragm are constantly connected ventrally around a small pore that apparently represents the flagellar pore allowing dorsoventral orientation of the cyst. The archaeopyle is apical type (tA)a with a typically small attached operculum.

Dimensions: Holotype. Endocyst, length: 24 µm, width: 22 µm; pericyst, length: 34 µm, width: 30 µm. Variations: Endocyst; length: 24(28)34 µm, width: 22(25)30 µm; pericyst; length: 30(35)38 µm, width: 24(31)35 µm. Number of specimens measured: 15.
Material: 97 specimens.

Description: The thick endophragm (1 to 3 µm), is densely adorned with warts (1 to 3 µm in diameter) of slightly variable size and density from one specimen to another. The periphragm is thin, smooth, hyaline and adorned by parasutural ridges; these ridges are thin, low, more or less discernible and sometimes accompanied by an alignment of small hollows (0.5 to 1 µm in diameter). The paratabulation is rudimentary and apparently of the gonyaulacoid type; the precingulate and postcingulate paraplates are vaguely marked, the paracingulum up to 8 µm wide is rarely indicated by two transverse ridges, and divides the cyst into an epicyst and a hypocyst which is about twice as large. Ventrally, the parasulcus is rarely visible and represented by an omegaform posterior paraplate (in the paratype). The margin of the archaeopyle is entire, the operculum (14 pm long in Phototype) is oval and constantly attached to the ventral edge of the archaeopyle.

Note: This species is characterized by the ovoid shape of its endocyst which is distinctly warty, by its vaguely tabulated perikysis, by the presence of a flagellar pore and by its apical archaeopyle with a typically attached operculum. Our species is provisionally assigned to the genus Uberidocysta because of the typically attached operculum and the presence of the flagellar pore. Uberidocysta? microverrucosa sp. nov. is conspecific with the specimen A'Hexagonifera chlamydata in WILSON (1971), H. verrucosa of WILSON (1974) unpublished and possibly with "Forma X sp. I" of MARHEINKCKK (1992) from the Maastrichtian of Hemmoor, Germany. Hexagonifera sp. B of WILLIAM S and BRIDEAUX (1975), Maastrichtian of Grand Banks (Canada) resembles a little to the species studied especially by the ornamentation of its endocyst and by its reduced pericoel. Uberidocysta? flagellichnia SCH0LER and WILSON (1993) differs from our species only by its granulated to vermiculated endophragm. SCH0LER and WILSON (1993) also separated L? flagellichnia from "Hexagonifera verrucosa" of WILSON (1974) and from "Forma X. sp. 1 " of MARHEINECKE (1992) which have a verrucous endophragm.

Stratiaphic distribution: Beutenaken: scale. 2 to 15, Halembaye: ex. 1 to 48; Lower Campanian - Maastrichtian upper. (Zone with G. quadrata - Zone with B. junior). Turnhout: -978 to -759.89 m, upper Campanian. - early Danian. In WILSON (1974). Upper Campanian - Maastrichtian inf. (Langei Zone - occidentalis Zone), Denmark; Upper Campanian - Maastrichtian inf. (mucronata Zone - lanceolata Zone), Maastricht region.
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