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Eocladopyxis furculum
From Fensome et al., 2019:
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Original description Awad and Oboh-Ikenobe, 2016:
Holotype: ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST- 1915-S21, EF N29, Late Paleocene. Plate II; 3.
Paratypes: Paratype 1. ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST-1915-S21, EF H27/1, Late Paleocene. Plate II; 4. Paratype 2. ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST- 1915-S21, EF N39/2, Late Paleocene. Plate II; 5.
Type Locality: Upper Paleocene of ODP Hole 959D, Côte d’Ivoire-Ghana Transform Margin, West Africa. Lithological unit III (Shipboard Scientific Party, 1996).
Etymology: From the Latin: “furcula”, meaning little fork, with reference to its short processes that expand distally.
Synonymy: Eocladopyxis sp. A (Edwards, 2001) plate 2; 7.
Diagnosis: A species of Eocladopyxis with numerous short processes that are distally open with a serrate or spinate margin.
Description: Proximochorate cyst, spherical to subspherical, moderately to strongly compressed dorso-ventrally, bowl-shaped when the operculum is not attached; with numerous, short nontabular processes, more than 10 per plate, that are open and expanded distally with a serrate or spinose margin. Paratabulation gonyaulacacean, indicated on hypocyst by narrow parasutural grooves. Plates 1000, 2000, 3000, 4000, 5000 and 6000 are discernible on the ventral and dorsal side of the hypocyst and all the plates are discernible on the operculum (4Aa þ 6P), which consists of the four apical plates that remain attached to each and the individual precingular plates.
Dimensions: Holotype: width x length with operculum: 63 72 mm, length without operculum: 35 mm, length of processes up to 5 mm. Paratype 1: width x length with operculum: 60 65 mm, length without operculum: 35 mm, length of processes: 4 mm. Paratype 2: width x length without operculum: 55 25 mm, length of processes: 5 mm. Average dimensions: length with operculum: 65e70 mm, length without operculum: 30e40 mm, width: 60e65 mm, Length of processes: 3e5 mm. 29 specimens measured Stratigraphic range: For the studied interval, Eocladopyxis furculum sp. nov. was observed only in ODP Hole 959D at 812.34 mbsf (Late Paleocene) where it has common abundance. However, the new species was also recorded in the Oligocene sediments at 411.71 mbsf (unpublished data).
Comparison: Eocladopyxis furculum sp. nov. differs from the other species of the genus by its short and distally expanded processes that are open distally and have serrate or spinose margins. Eocladopyxis furculum sp. nov is similar to Eocladopyxis peniculata (Morgenroth, 1966) in the lengths of the processes, which are 3e5 mm in the former and 3e7 mm in the latter. However, the distal ends of the processes differ in the two species because Eocladopyxis peniculata has distally pointed and closed acuminate processes, while Eocladopyxis furculum sp. nov has serrate or spinose pro cesses (Plate II; 7,8). Eocladopyxis tessellata (Liengjarern et al., 1980) has longer (8e15 mm), bi-to multifurcate processes with spinose distal end. Eocladopyxis furculum sp. nov. is similar to Eocladopyxis sp. A. (Edwards, 2001), but has shorter processes. Species of Polysphaeridium (Davey and Williams, 1966) and Homotryblium (Davey and Williams, 1966) are also chorate cysts with epicystal archaeopyle and compound opercula. However, Homotryblium has one process per plate, and Polysphaeridum lacks the parasutural groves that charaterize the hypocyst in Eocladopyxis (Stover and Evitt, 1978; Liengjarern et al., 1980).
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Original description Awad and Oboh-Ikenobe, 2016:
Holotype: ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST- 1915-S21, EF N29, Late Paleocene. Plate II; 3.
Paratypes: Paratype 1. ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST-1915-S21, EF H27/1, Late Paleocene. Plate II; 4. Paratype 2. ODP Hole 959D, 812.34 mbsf, sample CIG7, slide MST- 1915-S21, EF N39/2, Late Paleocene. Plate II; 5.
Type Locality: Upper Paleocene of ODP Hole 959D, Côte d’Ivoire-Ghana Transform Margin, West Africa. Lithological unit III (Shipboard Scientific Party, 1996).
Etymology: From the Latin: “furcula”, meaning little fork, with reference to its short processes that expand distally.
Synonymy: Eocladopyxis sp. A (Edwards, 2001) plate 2; 7.
Diagnosis: A species of Eocladopyxis with numerous short processes that are distally open with a serrate or spinate margin.
Description: Proximochorate cyst, spherical to subspherical, moderately to strongly compressed dorso-ventrally, bowl-shaped when the operculum is not attached; with numerous, short nontabular processes, more than 10 per plate, that are open and expanded distally with a serrate or spinose margin. Paratabulation gonyaulacacean, indicated on hypocyst by narrow parasutural grooves. Plates 1000, 2000, 3000, 4000, 5000 and 6000 are discernible on the ventral and dorsal side of the hypocyst and all the plates are discernible on the operculum (4Aa þ 6P), which consists of the four apical plates that remain attached to each and the individual precingular plates.
Dimensions: Holotype: width x length with operculum: 63 72 mm, length without operculum: 35 mm, length of processes up to 5 mm. Paratype 1: width x length with operculum: 60 65 mm, length without operculum: 35 mm, length of processes: 4 mm. Paratype 2: width x length without operculum: 55 25 mm, length of processes: 5 mm. Average dimensions: length with operculum: 65e70 mm, length without operculum: 30e40 mm, width: 60e65 mm, Length of processes: 3e5 mm. 29 specimens measured Stratigraphic range: For the studied interval, Eocladopyxis furculum sp. nov. was observed only in ODP Hole 959D at 812.34 mbsf (Late Paleocene) where it has common abundance. However, the new species was also recorded in the Oligocene sediments at 411.71 mbsf (unpublished data).
Comparison: Eocladopyxis furculum sp. nov. differs from the other species of the genus by its short and distally expanded processes that are open distally and have serrate or spinose margins. Eocladopyxis furculum sp. nov is similar to Eocladopyxis peniculata (Morgenroth, 1966) in the lengths of the processes, which are 3e5 mm in the former and 3e7 mm in the latter. However, the distal ends of the processes differ in the two species because Eocladopyxis peniculata has distally pointed and closed acuminate processes, while Eocladopyxis furculum sp. nov has serrate or spinose pro cesses (Plate II; 7,8). Eocladopyxis tessellata (Liengjarern et al., 1980) has longer (8e15 mm), bi-to multifurcate processes with spinose distal end. Eocladopyxis furculum sp. nov. is similar to Eocladopyxis sp. A. (Edwards, 2001), but has shorter processes. Species of Polysphaeridium (Davey and Williams, 1966) and Homotryblium (Davey and Williams, 1966) are also chorate cysts with epicystal archaeopyle and compound opercula. However, Homotryblium has one process per plate, and Polysphaeridum lacks the parasutural groves that charaterize the hypocyst in Eocladopyxis (Stover and Evitt, 1978; Liengjarern et al., 1980).