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Protoellipsodinium ornatum
Plate 1, Figures 7-14
Holotype: Plate 1, Figure 7, 8
Paratype: Plate 1, Figure 13, 14
Type Locality: Speeton Bed C8B, early Hauterivian, regale ammonite Zone. Holotype: Slide upper C8B(1), E.F. T48.4.
Paratype: Slide baseC8B(2), E.F. Q46.2.
Derivation of Name: From the Latin ornatus, adorned, embellished- in reference to the relatively complex spines.
Diagnosis: A smooth to finely fibro-perforate, rounded ovoidal species bearing fairly numerous long, flexuous, processes which are capitate or terminate in several very fine distal spines. Processes are usually isolated, having circular contacts with the main body, although some proximal flattening of their bases can occur. Each process has vacuoles running its full length. Tabulation is indicated only by the single plate precingular archeopyle.
Dimensions: Holotype: Central body 38 × 33 μm. Overall 56 × 46 μm.
Paratype: Central body 33 × 28 μm. Overall 48 × 46 μm.
All measured specimens: Central body 46 (39) 33 μm × 38 (33) 28 μm.
Overall: 56 (52) 48 μm × 51 (46) 43 μm
Specimens Measured: 9.
Remarks: Protoellipsodinium ornatum is similar to Protoellipsodinium percultum Duxbury n. sp. in having small vacuoles running the full length of each process but it is smaller, more rounded and has fewer processes which are distally capitate or more complex distally, as opposed to the simple, acuminate spine terminations of P. percultum. Vacuoles were also described for Protoellipsodinium vacuolatum Duxbury 2018, but that species is smaller, with short, acuminate spines and with vacuoles present only at spine bases and running along low crests, where present. The presence of capitate to distally complex process terminations in Protoellipsodinium ornatum Duxbury n. sp., a species restricted to Speeton Beds C9A to C8B (early Hauterivian, upper regale ammonite Zone), is unusual for sediments so old. Duxbury (2019, p. 200) included in Protoellipsodinium clavulus Davey and Verdier 1974 subsp. spinigerus Brideaux 1977 representatives of that species with more elaborate process terminations, beyond those which are “basically capitate”, and such forms were shown in Duxbury (op. cit.) to range no older than the late Barremian, palynofloral Zone LKP22. Protoellipsodinium clavulus clavulus (with capitate spines) ranges significantly older, but only to the base of the late Barremian. Unlike P. ornatum, P. clavulus displays no process vacuoles.
Holotype: Plate 1, Figure 7, 8
Paratype: Plate 1, Figure 13, 14
Type Locality: Speeton Bed C8B, early Hauterivian, regale ammonite Zone. Holotype: Slide upper C8B(1), E.F. T48.4.
Paratype: Slide baseC8B(2), E.F. Q46.2.
Derivation of Name: From the Latin ornatus, adorned, embellished- in reference to the relatively complex spines.
Diagnosis: A smooth to finely fibro-perforate, rounded ovoidal species bearing fairly numerous long, flexuous, processes which are capitate or terminate in several very fine distal spines. Processes are usually isolated, having circular contacts with the main body, although some proximal flattening of their bases can occur. Each process has vacuoles running its full length. Tabulation is indicated only by the single plate precingular archeopyle.
Dimensions: Holotype: Central body 38 × 33 μm. Overall 56 × 46 μm.
Paratype: Central body 33 × 28 μm. Overall 48 × 46 μm.
All measured specimens: Central body 46 (39) 33 μm × 38 (33) 28 μm.
Overall: 56 (52) 48 μm × 51 (46) 43 μm
Specimens Measured: 9.
Remarks: Protoellipsodinium ornatum is similar to Protoellipsodinium percultum Duxbury n. sp. in having small vacuoles running the full length of each process but it is smaller, more rounded and has fewer processes which are distally capitate or more complex distally, as opposed to the simple, acuminate spine terminations of P. percultum. Vacuoles were also described for Protoellipsodinium vacuolatum Duxbury 2018, but that species is smaller, with short, acuminate spines and with vacuoles present only at spine bases and running along low crests, where present. The presence of capitate to distally complex process terminations in Protoellipsodinium ornatum Duxbury n. sp., a species restricted to Speeton Beds C9A to C8B (early Hauterivian, upper regale ammonite Zone), is unusual for sediments so old. Duxbury (2019, p. 200) included in Protoellipsodinium clavulus Davey and Verdier 1974 subsp. spinigerus Brideaux 1977 representatives of that species with more elaborate process terminations, beyond those which are “basically capitate”, and such forms were shown in Duxbury (op. cit.) to range no older than the late Barremian, palynofloral Zone LKP22. Protoellipsodinium clavulus clavulus (with capitate spines) ranges significantly older, but only to the base of the late Barremian. Unlike P. ornatum, P. clavulus displays no process vacuoles.