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Pentadinium galileoi

Pentadinium galileoi Sancay et al., 2007, p.537–538,540, pl.1, figs.1–20, text-fig.4.

Holotype: Sancay et al., 2007, pl.1, figs.1–4.
Age: Maastrichtian.
Occurrence: Eastern Anatolia, Turkey, rare in Keleres (Yazla) Formation and common in Askale Formation, Oligocene-Lower Miocene, correlation based on dinoflagellate, acritarch, spore-pollen, foraminifera, and nannofossils (Sancay 2005; Sancay et al. 2006; Bati and Sancay in review).

Original description (Sancay et al., 2007):
Pentadinium galileoi Sancay, Bati, Edwards and Ertug, n. sp. Plate 1, figures 1-4
Shape: sphaerical, chorate with prominant discodial cingulum and slender, distally furcate apical, sulcal, and antapical processes.
Wall features: granular in intraplate areas, gonal spines at apex, posterior intercalary, and antapex, processes at gonal positions may be on a variably developed antapical ‘skirt’ formed by extended septa (2-3µm), minute bifurcate spines intergonally and along cingulum at plate intersections; larger process at apex may indicate presence of preapical plates. Process length 7.5-15µm.
Wall relationships: Periphragm and endophragm appressed except at cingular area and at septa. A broad paracingular flange consists mainly of adcingular parts of the pre- and postcingular plates separated by true cingular plates up to 15 µm wide. Parasutural septa are 7.5 to15 µm high and give rise to gonal spines.
Archeopyle: Type P (3''), periarcheopyle larger than endoarcheopyle.
Tabulation: gonyaulacoid, 1pr, 3-4', 6'',6c, 6''', 1p, 1'''', small sulcal plates may be indicated by additional spines/processes (text-figure 4).
Size: Polar diameter of the holotype is 84µm to 80µm. Polar diameter of the other specimens range between 73µm to 89µm with an avarage of 84µm, endocyst diameter ranges between 51µm to 67µm with an average of 63µm (measurements have been taken from 10 representative specimens).
Etymology: Named in honor of Galilei Galileo who first discovered rings around the planet Saturn.
Holotype: Specimen illustrated in plate 1, figures 1-4, Sample No: 116-1 (Ebulbahar Section), England Finder reference J21.
Repository: Turkish Petroleum Corporation, Research Center, Palynology Laboratory (archive number: 8086-87)

Affinities/Comparisons:
This species resembles the Eocene forms Pentadinium goniferum Edwards 1982 and Pentadinium polypodum Edwards 1982 in having processes, but differs from both in surface texture (granulate as opposed to coarsely vermiculate in Pentadinium goniferum Edwards 1982 and shagreenate in Pentadinium polypodum Edwards 1982) and process type. The processes in Pentadinium galileoi nov. sp., although somewhat variable, are noticeably narrower distally and have bifurcate or trifurcate terminations. The flange in the cingular area in Pentadinium galileoi nov. sp. (that is mostly made up of parts of pre- and postcingular plates) may be smooth or bear lacy openings. Septa form a more conspicuous projecting awning over the archeopyle than in previously named species. End members of this species superficially resemble Pentadinium membranaceum (Eisenack 1965) Stover and Evitt 1978, but the higher septa in the apical area and the lack of a closed ‘skirt’ in the antapical area yield an equant rather than an elongate overall shape; also the surface texture is granulate as opposed to coarsely vermiculate. This species differs from the middle Miocene species Pentadinium spinulum Strauss and Lund 1992 in having pronounced gonal processes and a paracingulum that is more highly inflated relative to the septa on the epi- and hypocyst. It has spines similar to the spines typical of Pentadinium spinulum Strauss and Lund 1992, but the gonal processes in Pentadinium galileoi nov. sp. make these spines appear less prominent. Pentadinium galileoi nov. sp. could perhaps have evolved into Pentadinium spinulum Strauss and Lund 1992 by the reduction of the gonal processes.
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