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Pontiadinium pecsvaradense
Pontiadinium pecsvaradense Suto-Szentai, 1982
Now Impagidinium?. Originally Pontiadinium, subsequently (and now) Impagidinium?.
Questionable assignment: Lentin and Williams (1989, p.196).
Holotype: Suto-Szentai, 1982, pl.3, figs.1[a-b]; text-fig.4
Age: Pannonian
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Baranyi et al., 2022
Holotype. Sütő-Szentai (1982, p. 227, pl. III, fig. 1). Borehole Pécsvárad 15/T-22, depth 64.0–63.0 m, microscope coordinates (Zeiss) 10.5/90.8. Housed in the holotype collection at the Local History and Natural History Collection of Komló (Komló, Hungary).
Lectotype. Supplementary material 5, Figures S4–S6. Borehole Pécsvárad 15/T-22, depth 64.0–63.0 m, England Finder coordinate W36. Housed in the holotype collection at the Local History and Natural History Collection of Komló (Komló, Hungary).
Original description. Sütő-Szentai (1982, p. 218) reported that the theca is ovoid in outline. She described the cyst as follows: Its apical and antapical poles emerge from the plankton body. The antapical pole is somewhat less developed than the apical one and is asymmetrically curved. The meridional asymmetry, i.e. that the plankton body in the direction of the row of cingulum tabulae 5, 4, 3 to the left of the sulcus and in that of tabulation 4″, 3″, 5″ and 4″′ is more inflated than on the opposite side, is characteristic feature of the plankton body. Its wall is 2 µ thick and finely perforate. Tabulation: 4′, 6″, 6c, 6″′, 1p, 1″′′, 4 s. The tabula 6″ of the epitheca is triangular, its peak pointed, in a direct contact with the tabula 4′. Tabula 4′ rhomboidal. Tabulae 1″ and 5″ of the epitheca pentagonal, tabula 2″ trapezoidal and much less high than the neighbouring ones. Archeopyle: 3″, trapezoidal.
Comment. The taxonomic model of Sütő-Szentai (1982) inappropriately interprets proximate and chorate dinoflagellate cysts as life-form stages of the same taxon. In her interpretation, the proximate cysts in Lake Pannon sediments represent the thecate motile (‘plankton’) stage because of a resemblance to thecate cells of Gonyaulax digitalis and a misunderstanding of the cyst–theca relationship (e.g. as reported in Wall and Dale Citation1968).
Emended description. Proximate dinoflagellate cyst with biconical and ovoidal shape. The cyst has short, rounded apical and antapical horns which are usually of equal length or the antapical protuberance is somewhat smaller. Low sutural features display a presumed standard gonyaulacacean S-type ventral tabulation pattern (Plate 2, figures 9–12). Occasionally, the sutural features appear to be slightly raised by short (∼2.0–3.0 µm in height) rod-like luxuriae supporting the traces of a trabeculate septa (, figures 1–2, 9–10). The precingular 6″ is triangular with direct limited contact with the apical 4′ plate (Plate 2, figures 11–12). The archeopyle is pentagonal and camerate formed by the loss of precingular plate 3″ (Plate 2, figures 1–2, 5). The wall is scabrate-granulate or verrucate and ∼0.9–1.5 µm thick and only rarely has traces of microperforations (Plate 2, figure 5).
Dimensions. The maximum length of the cyst body including the polar protuberances is 67 (82) 106 µm, and the maximum equatorial width is 48 (63) 76 µm. The length of the apical horn is 5 (10) 13 µm; the antapical horn is 3 (3.5) 4 µm in length. Thirteen specimens were measured from the PAET 34P and the holotype material. The holotype is 80 µm in length, and the equatorial width is 60 µm (Sütő-Szentai Citation1982). The lectotype is 78 µm in length, equatorial width is 62 µm, apical horn length is 5 µm and antapical horn length is 3 µm.
Comments and comparisions. Based on the material from the Našice PAET 34P core, and a reexamination of the holotype material (Supplementary material 5), the species description of Pontiadinium pecsvaradensis is emended here. The holotype could not be retrieved because of the desiccated glycerine jelly that left only part of the syntypes recognisable (Supplementary material 5, Figures S1–S3). A lectotype was designated from the same slide and is illustrated in Supplementary material 5, Figures S4–S6. Sütő-Szentai (Citation1982) incorrectly described a theca morphology and failed to report details of the plate suture structure that are critical to distinguishing the Pontiadinium species. The specimen labelled Gonyaulacysta sp. 6 K in Balteş (Citation1971) has a well-developed short apical horn, smaller antapical protuberance and raised sutural structure with a beaded appearance, making it comparable to Pontiadinium pecsvaradensis. Lentin and Williams (Citation1989) questionably re-assigned Gonyaulacysta sp. 6 K of Balteş (Citation1971) to Impagidinium? pecsvaradense although the antapical protuberance is not a characteristic of Impagidinium as described by Stover and Evitt (Citation1978); thus, we retain the species in Pontiadinium. Pontiadinium pecsvaradensis differs from Pontiadinium obesum by its slightly elongated oval or spindle-shaped ambitus with an L:W ratio of 1.4–2.0 for the population of the PAET boreholes, compared to the low L:W ratio (1.2–1.4) in the more spherical-rhomboidal Pontiadinium obesum cysts, and by the more prominent and varied septal development. Pontiadinium obesum cysts have low (∼1.1–1.5 µm in height), narrow simple sutural septa, while the sutural features of Pontiadinium pecsvaradensis tend to be slightly raised, with a beaded appearance, and occasionally they show traces of rod-like luxuriae supporting a trabeculate septa (Plate 2, figures 1–2, 9–10). The cyst wall surface of Pontiadinium pecsvaradensis is more varied, with scabrate-granulate to verrucate ornamentation, while the surface ornament of Pontiadinium obesum specimens is uniformly scabrate-granulate.
Now Impagidinium?. Originally Pontiadinium, subsequently (and now) Impagidinium?.
Questionable assignment: Lentin and Williams (1989, p.196).
Holotype: Suto-Szentai, 1982, pl.3, figs.1[a-b]; text-fig.4
Age: Pannonian
----------------------------------------------------------------------------------------------------------------------------------
Baranyi et al., 2022
Holotype. Sütő-Szentai (1982, p. 227, pl. III, fig. 1). Borehole Pécsvárad 15/T-22, depth 64.0–63.0 m, microscope coordinates (Zeiss) 10.5/90.8. Housed in the holotype collection at the Local History and Natural History Collection of Komló (Komló, Hungary).
Lectotype. Supplementary material 5, Figures S4–S6. Borehole Pécsvárad 15/T-22, depth 64.0–63.0 m, England Finder coordinate W36. Housed in the holotype collection at the Local History and Natural History Collection of Komló (Komló, Hungary).
Original description. Sütő-Szentai (1982, p. 218) reported that the theca is ovoid in outline. She described the cyst as follows: Its apical and antapical poles emerge from the plankton body. The antapical pole is somewhat less developed than the apical one and is asymmetrically curved. The meridional asymmetry, i.e. that the plankton body in the direction of the row of cingulum tabulae 5, 4, 3 to the left of the sulcus and in that of tabulation 4″, 3″, 5″ and 4″′ is more inflated than on the opposite side, is characteristic feature of the plankton body. Its wall is 2 µ thick and finely perforate. Tabulation: 4′, 6″, 6c, 6″′, 1p, 1″′′, 4 s. The tabula 6″ of the epitheca is triangular, its peak pointed, in a direct contact with the tabula 4′. Tabula 4′ rhomboidal. Tabulae 1″ and 5″ of the epitheca pentagonal, tabula 2″ trapezoidal and much less high than the neighbouring ones. Archeopyle: 3″, trapezoidal.
Comment. The taxonomic model of Sütő-Szentai (1982) inappropriately interprets proximate and chorate dinoflagellate cysts as life-form stages of the same taxon. In her interpretation, the proximate cysts in Lake Pannon sediments represent the thecate motile (‘plankton’) stage because of a resemblance to thecate cells of Gonyaulax digitalis and a misunderstanding of the cyst–theca relationship (e.g. as reported in Wall and Dale Citation1968).
Emended description. Proximate dinoflagellate cyst with biconical and ovoidal shape. The cyst has short, rounded apical and antapical horns which are usually of equal length or the antapical protuberance is somewhat smaller. Low sutural features display a presumed standard gonyaulacacean S-type ventral tabulation pattern (Plate 2, figures 9–12). Occasionally, the sutural features appear to be slightly raised by short (∼2.0–3.0 µm in height) rod-like luxuriae supporting the traces of a trabeculate septa (, figures 1–2, 9–10). The precingular 6″ is triangular with direct limited contact with the apical 4′ plate (Plate 2, figures 11–12). The archeopyle is pentagonal and camerate formed by the loss of precingular plate 3″ (Plate 2, figures 1–2, 5). The wall is scabrate-granulate or verrucate and ∼0.9–1.5 µm thick and only rarely has traces of microperforations (Plate 2, figure 5).
Dimensions. The maximum length of the cyst body including the polar protuberances is 67 (82) 106 µm, and the maximum equatorial width is 48 (63) 76 µm. The length of the apical horn is 5 (10) 13 µm; the antapical horn is 3 (3.5) 4 µm in length. Thirteen specimens were measured from the PAET 34P and the holotype material. The holotype is 80 µm in length, and the equatorial width is 60 µm (Sütő-Szentai Citation1982). The lectotype is 78 µm in length, equatorial width is 62 µm, apical horn length is 5 µm and antapical horn length is 3 µm.
Comments and comparisions. Based on the material from the Našice PAET 34P core, and a reexamination of the holotype material (Supplementary material 5), the species description of Pontiadinium pecsvaradensis is emended here. The holotype could not be retrieved because of the desiccated glycerine jelly that left only part of the syntypes recognisable (Supplementary material 5, Figures S1–S3). A lectotype was designated from the same slide and is illustrated in Supplementary material 5, Figures S4–S6. Sütő-Szentai (Citation1982) incorrectly described a theca morphology and failed to report details of the plate suture structure that are critical to distinguishing the Pontiadinium species. The specimen labelled Gonyaulacysta sp. 6 K in Balteş (Citation1971) has a well-developed short apical horn, smaller antapical protuberance and raised sutural structure with a beaded appearance, making it comparable to Pontiadinium pecsvaradensis. Lentin and Williams (Citation1989) questionably re-assigned Gonyaulacysta sp. 6 K of Balteş (Citation1971) to Impagidinium? pecsvaradense although the antapical protuberance is not a characteristic of Impagidinium as described by Stover and Evitt (Citation1978); thus, we retain the species in Pontiadinium. Pontiadinium pecsvaradensis differs from Pontiadinium obesum by its slightly elongated oval or spindle-shaped ambitus with an L:W ratio of 1.4–2.0 for the population of the PAET boreholes, compared to the low L:W ratio (1.2–1.4) in the more spherical-rhomboidal Pontiadinium obesum cysts, and by the more prominent and varied septal development. Pontiadinium obesum cysts have low (∼1.1–1.5 µm in height), narrow simple sutural septa, while the sutural features of Pontiadinium pecsvaradensis tend to be slightly raised, with a beaded appearance, and occasionally they show traces of rod-like luxuriae supporting a trabeculate septa (Plate 2, figures 1–2, 9–10). The cyst wall surface of Pontiadinium pecsvaradensis is more varied, with scabrate-granulate to verrucate ornamentation, while the surface ornament of Pontiadinium obesum specimens is uniformly scabrate-granulate.