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Trinovantedinium uitpensis

Trinovantedinium uitpensis sp. nov., Cárdenas et al., 2021

Holotype: Cárdenas et al. 2021, Plate II, 1–3
Type locality: Cocinetas Basin, La Guajira, Colombia; Stratigraphic horizon: Uitpa Formation
Age: Aquitanian, early Miocene

Original description: Cárdenas et al., 2021:

Diagnosis:
Peridinioid cyst moderately dorsoventrally compressed, proximate, acavate. Pentagonal outline in dorsoventral view wider than long: straight to slightly convex epicyst with rounded apex; straight to slightly concave hypocyst with two antapical horns. Autophragm smooth with verrucate to slightly baculate penitabular ornamentation. Cingulum planar to slightly helicoidal with denticulated margins. Archeopyle intercalary hexa 2a, presumably isodeltalinteloid. Operculum free to adherent.

Description:
Peridinioid cyst proximate, acavate and moderately dorsoventrally compressed with pentagonal outline in dorsoventral view: sides of the epicyst are straight to slightly convex, whereas sides of the hypocyst are straight to slightly concave. The cyst is wider than long, and therefore, five of the eight specimens found are in polar orientation presumably due to post-depositional compression (Plate II,
4–11). Lengths of the epicyst and the hypocyst are approximately equal. The apex is rounded and the antapex has two slightly asymmetrical horns, up to ~12.5 μm long, distally tapering into rounded tips. The antapical depression is shallow and wide.
Wall: single-layered (autophragm), ~0.4 μm thick and light brown in color. The autophragm is smooth with verrucate to slightly baculate penitabular ornamentation. Verrucae are solid, ~ 1.0 μm wide and ~ 1.0 μm long. Baculae aremsolid, ~1.0 μm wide and ~1.4 μm long. The cingulum is planar to slightly
helicoidal, indicated by two denticulate folds and interrupted ventrally by an unornamented sulcal region. The cingular area may be slightly inflated. Cingular baculae are solid or hollow, usually connected proximally, ~ 1.0 μm wide and ~ 2.5 μm long.
Archeopyle: formed by the release of the anterior intercalary plate 2a and presumably hexagonal isodeltalinteloid (Plate II, 8–9)
Operculum: free and sometimes adherent on adcingular margin

Dimensions:
Holotype: length, 48 μm; width, 53 μm
Range: length, 38–48 μm; width, 51–73 μm
Three specimens measured.

Affinities/Comparison:
Trinovantedinium uitpensis sp. nov. differs from other species in the genus by having denticulate cingulum and verrucate to slightly baculate ornamentation elsewhere (Fig. 5). Ornamentation in species of Trinovantedinium vary as follows: T. applanatum: acuminate and slightly capitate; T. boreale: capitate; T. ferugnomatum: acuminate, capitate and bifid; T. glorianum: acuminate, truncated and occasionally bifid; T. harpagonium: taeniate and flared to infundibular; T. henrietii: flared; T. pallidifulvum: acuminate; T. papula: acuminate, capitate and rarely distally bifurcate; T. sterthense: capitate; T. variabile: considerable variation but mostly flared and aculeate, occasionally irregularly branched (see Bujak, 1984, p. 194, Text-fig. 3); T.? xylochoporum: tubiform and tapering, distally ramified.
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