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Cannosphaeropsis frielingii
Plate 3, figs. A–L.
Derivation of name. Named in honor of Dr. Joost Frieling in recognition of his achievements in marine palynology and work on the PETM at Utrecht University, at Oxford University, and soon at Ghent University.
Diagnosis. A species of Cannosphaeropsis with thick vesiculate trabeculae and gonal platforms.
Holotype. Plate 3, figs. A–C, SDB 204.51m R33.4.
Paratypes. Paratype 1: Plate 3, figs. D–F, SDB 204.84m R43. Paratype 2: Plate 3, figs. G–H, BR 357.39m H36. Paratype 3: Plate 3, figs. I & L, CL 103.04m M47. Paratype 4: Plate 3, figs. J–K, SDB 204.51m K13.
Material. South Dover Bridge (SDB) core, Talbot County, Maryland, USA.
Type locality and horizon. South Dover Bridge (SDB) core, latest Paleocene, 204.51 m.
Age. Latest Paleocene.
Description.
Shape: Cyst proximochorate to chorate. Central body subspherical to slightly elongate.
Wall relationships: autophragm smooth to finely granulate, bearing processes connecting the autophragm to ectophragmal thick vesiculate trabeculae.
Wall features: Ectophragmal network formed by single parasutural trabeculae that connect the distal ends of gonal processes. At gonal positions branches are present.
Processes: The vesiculate trabeculae network is mostly oriented in dorsal direction with thick processes connecting this network to the autophragm. Ventral processes are present, but these are shorter and do not connect to the trabeculae network. Processes are bi- or trifurcate. No trabecular spines midway between gonal positions indicated. “Gonal plates” are present at intersects between trabecula. Trabecula show thickening towards gonal platforms.
Paratabulation: Difficult to determine, indicated by trabeculae only.
Archeopyle: Precingular, Type P (300), operculum free.
Paracingulum: not well visible, can be indicated by network of trabeculae.
Parasulcus: not well visible, can be indicated by parasutural trabeculae.
Dimensions: Holotype: endocyst width 33 μm; total cyst length 73 μm, length apical process 13 μm, thickness trabecula, 2 μm. Other types: endocyst width 33–43 μm; total cyst length 68–76 μm, length apical process 13–15 μm, thickness trabecula, 1–2 μm (n D 5).
Stratigraphic range/occurrence. Latest Paleocene.
Remarks. Cannosphaeropsis frielingii sp. nov. differs from the overall similar Cannosphaeropsis utinensis (Wetzel, 1932) in having alveolate trabecula containing vesicles and by lacking trabecular spines that are present in C. utinensis. The vesicles in C. frielingii are larger compared to the alveolate autophragm and/or trabecula in Cannosphaeropsis passio (de Verteil and Norris, 1996). Furthermore, the trabeculae are wider compared to C. passio, and no gonal platforms are present in C. passio. Similarly to Cannosphaeropsis quattrocchiae (Guerstein et al., 2001), C. frielingii has “gonal platforms”. The difference between C. quattrocchiae and C. frielingii is that C. frielingii has microperforate gonal platforms, which is not seen in C. frielingii. Furthermore, in C. quattrocchiae, the trabeculae bear a thin crest that gives a fibrous appearance and is not alveolate. The size of structural voids and vesicles within various species within the genus Cannosphaeropsis has been used as a diagnostic trait. McLachlan et al. (2021) show that the degree of vesiculation varies within a group of 400 specimens in the species Cannosphaeropsis franciscana (Damassa, 1979) and assigned subspecies (McLachlan et al., 2021). Nevertheless, Cannosphaeropsis frielingii sp. nov. differs from other species within this genus based on other features than just the degree of vesiculation alone.
Derivation of name. Named in honor of Dr. Joost Frieling in recognition of his achievements in marine palynology and work on the PETM at Utrecht University, at Oxford University, and soon at Ghent University.
Diagnosis. A species of Cannosphaeropsis with thick vesiculate trabeculae and gonal platforms.
Holotype. Plate 3, figs. A–C, SDB 204.51m R33.4.
Paratypes. Paratype 1: Plate 3, figs. D–F, SDB 204.84m R43. Paratype 2: Plate 3, figs. G–H, BR 357.39m H36. Paratype 3: Plate 3, figs. I & L, CL 103.04m M47. Paratype 4: Plate 3, figs. J–K, SDB 204.51m K13.
Material. South Dover Bridge (SDB) core, Talbot County, Maryland, USA.
Type locality and horizon. South Dover Bridge (SDB) core, latest Paleocene, 204.51 m.
Age. Latest Paleocene.
Description.
Shape: Cyst proximochorate to chorate. Central body subspherical to slightly elongate.
Wall relationships: autophragm smooth to finely granulate, bearing processes connecting the autophragm to ectophragmal thick vesiculate trabeculae.
Wall features: Ectophragmal network formed by single parasutural trabeculae that connect the distal ends of gonal processes. At gonal positions branches are present.
Processes: The vesiculate trabeculae network is mostly oriented in dorsal direction with thick processes connecting this network to the autophragm. Ventral processes are present, but these are shorter and do not connect to the trabeculae network. Processes are bi- or trifurcate. No trabecular spines midway between gonal positions indicated. “Gonal plates” are present at intersects between trabecula. Trabecula show thickening towards gonal platforms.
Paratabulation: Difficult to determine, indicated by trabeculae only.
Archeopyle: Precingular, Type P (300), operculum free.
Paracingulum: not well visible, can be indicated by network of trabeculae.
Parasulcus: not well visible, can be indicated by parasutural trabeculae.
Dimensions: Holotype: endocyst width 33 μm; total cyst length 73 μm, length apical process 13 μm, thickness trabecula, 2 μm. Other types: endocyst width 33–43 μm; total cyst length 68–76 μm, length apical process 13–15 μm, thickness trabecula, 1–2 μm (n D 5).
Stratigraphic range/occurrence. Latest Paleocene.
Remarks. Cannosphaeropsis frielingii sp. nov. differs from the overall similar Cannosphaeropsis utinensis (Wetzel, 1932) in having alveolate trabecula containing vesicles and by lacking trabecular spines that are present in C. utinensis. The vesicles in C. frielingii are larger compared to the alveolate autophragm and/or trabecula in Cannosphaeropsis passio (de Verteil and Norris, 1996). Furthermore, the trabeculae are wider compared to C. passio, and no gonal platforms are present in C. passio. Similarly to Cannosphaeropsis quattrocchiae (Guerstein et al., 2001), C. frielingii has “gonal platforms”. The difference between C. quattrocchiae and C. frielingii is that C. frielingii has microperforate gonal platforms, which is not seen in C. frielingii. Furthermore, in C. quattrocchiae, the trabeculae bear a thin crest that gives a fibrous appearance and is not alveolate. The size of structural voids and vesicles within various species within the genus Cannosphaeropsis has been used as a diagnostic trait. McLachlan et al. (2021) show that the degree of vesiculation varies within a group of 400 specimens in the species Cannosphaeropsis franciscana (Damassa, 1979) and assigned subspecies (McLachlan et al., 2021). Nevertheless, Cannosphaeropsis frielingii sp. nov. differs from other species within this genus based on other features than just the degree of vesiculation alone.