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Leffingwellia costata
Leffingwellia costata Head and Norris, 2003, p.12,14, fig.10; fig.12, nos.16–25.
Acritarch.
Holotype: Head and Norris, 2003, fig.12, nos.16–18.
Age: late early–late Pliocene.
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Original description: [Head and Norris, 2003]:
LEFFINGWELLIA COSTATA new species
Figures 10, 11, 12.16–12.25
Incertae sedis B. HEAD IN HEAD AND WESTPHAL, 1999, p. 22, fig. 15.3, 15.4.
Diagnosis. -- Main body ornamented with low, sinuous to subparallel anastomosing ridges that often extend onto appendages.
Description. -- Elongate palynomorph; main body proximally round-ended, and bears low (about 1.0 μm or less in width and height) sinuous to subparallel anastomosing ridges on outer surface. Ridge crests appear sharp. Ornament extends onto proximal ends of appendages, becoming progressively less well developed or smooth distally. Wall of main body usually considerably thicker than of appendages (e.g., holotype, Fig. 12.16–12.18), but thicknesses may be similar in some specimens (e.g., Fig. 12.22–12.25). Each appendage tapers distally; has u- or c-shaped transverse section (Fig. 10); thinning of wall often occurs towards lateral margins which are entire.
Etymology. -- Latin, costa, ridge; with reference to the ridged ornament on this species.
Type. -- Holotype, sample DSDP 603C-5-5, 100–102 μm; slide 1 (ROM 55071); England Finder reference Q41/2. Upper Pliocene. Figure 12.16–12.18.
Measurements.-- Holotype: total length 66 μm, breadth 26 μm, maximum wall thickness 2.5 μm, ratio of main body length/total length 0.30. Range of Hole 603C specimens: total length 45 (59.0) 71 μm, breadth 23 (25.3) 27 mm, maximum wall thickness 1.0 (2.3) 3.0 μm, ratio of main body length/total length 0.26 (0.30) 0.37. Eight specimens measured. See also Figure 11.
Material examined. -- Eight specimens from a single sample from DSDP 603C (603C-5-5, 100–102 μm). One specimen from the Clino Core, Bahamas, illustrated in Head and Westphal (1999, p. 22, fig. 15.3, 15.4).
Occurrence.-- Upper Pliocene of DSDP 603C, and upper Lower Pliocene of the Clino Core, Bahamas (as Incertae sedis B of Head in Head and Westphal, 1999).
Comparison. -- Incertae sedis A of Head in Head and Westphal (1999), represented by two specimens from the Lower Pliocene of the Bahamas, differs from Leffingwellia costata n. sp. in having an ornament of low verrucae on the main body.
Acritarch.
Holotype: Head and Norris, 2003, fig.12, nos.16–18.
Age: late early–late Pliocene.
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Head and Norris, 2003]:
LEFFINGWELLIA COSTATA new species
Figures 10, 11, 12.16–12.25
Incertae sedis B. HEAD IN HEAD AND WESTPHAL, 1999, p. 22, fig. 15.3, 15.4.
Diagnosis. -- Main body ornamented with low, sinuous to subparallel anastomosing ridges that often extend onto appendages.
Description. -- Elongate palynomorph; main body proximally round-ended, and bears low (about 1.0 μm or less in width and height) sinuous to subparallel anastomosing ridges on outer surface. Ridge crests appear sharp. Ornament extends onto proximal ends of appendages, becoming progressively less well developed or smooth distally. Wall of main body usually considerably thicker than of appendages (e.g., holotype, Fig. 12.16–12.18), but thicknesses may be similar in some specimens (e.g., Fig. 12.22–12.25). Each appendage tapers distally; has u- or c-shaped transverse section (Fig. 10); thinning of wall often occurs towards lateral margins which are entire.
Etymology. -- Latin, costa, ridge; with reference to the ridged ornament on this species.
Type. -- Holotype, sample DSDP 603C-5-5, 100–102 μm; slide 1 (ROM 55071); England Finder reference Q41/2. Upper Pliocene. Figure 12.16–12.18.
Measurements.-- Holotype: total length 66 μm, breadth 26 μm, maximum wall thickness 2.5 μm, ratio of main body length/total length 0.30. Range of Hole 603C specimens: total length 45 (59.0) 71 μm, breadth 23 (25.3) 27 mm, maximum wall thickness 1.0 (2.3) 3.0 μm, ratio of main body length/total length 0.26 (0.30) 0.37. Eight specimens measured. See also Figure 11.
Material examined. -- Eight specimens from a single sample from DSDP 603C (603C-5-5, 100–102 μm). One specimen from the Clino Core, Bahamas, illustrated in Head and Westphal (1999, p. 22, fig. 15.3, 15.4).
Occurrence.-- Upper Pliocene of DSDP 603C, and upper Lower Pliocene of the Clino Core, Bahamas (as Incertae sedis B of Head in Head and Westphal, 1999).
Comparison. -- Incertae sedis A of Head in Head and Westphal (1999), represented by two specimens from the Lower Pliocene of the Bahamas, differs from Leffingwellia costata n. sp. in having an ornament of low verrucae on the main body.