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Spiniferites hexatypicus
Spiniferites hexatypicus Matsuoka, 1983
Taxonomic junior synonym: Spiniferites ovatus Bujak, according to Bujak and Matsuoka (1986, p.239).
Holotype: Matsuoka, 1983, pl.13, figs.1ab
Age: Middle-Late Miocene
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Original description: [Matsuoka, 1983b]:
Spiniferites hexatypicus sp. nov.
PI. 13, figs. 1-3, Text-Fig. 18
Derivation of name: Greek, hexa + typicus, hexagonal shaped, with reference to the hexagonal cyst body.
Diagnosis: Cyst relatively long and rounded hexagonal, and having smooth to finely granular surface. Epicyst trapezoidal in shape, and hypocyst nearly trapezoidal in shape. Processes short, solid, gonal only and simple or small bifid distally. Proximal base of processes somewhat membraneous. Archeopyle simple precingular and formed by loss of the 3 paraplate.
Holotype: KMD slide NTE 3a-3 (8.3/134.7), pl. 13, fig. 1. Sample NTE 3a, Teradomari Formation - Middle to Late Miocene. Loc.: Teradomari, Teradomari-cho, Niigata Prefecture, Central Japan.
Description: The intermediate proximochorate cyst is rounded hexagonal in shape and consists of two layers, periphragm and endophragm adpressed between processes. The periphragm has a smooth to finely granular surface. The epicyst without apical boss shows a rounded trapezoidal shape. The hypocyst marks a trapezoidal outlne in equatorial view. The processes are composed of only short, solid and gonal type with simple or small bifurcate recurved distal extremities. The archeopyle is a simple precingular type derived from loss of the 3" paraplate. The paratabulation is represented by parasuture as the follow; 4', 0a, 6", 6c, 6'", 1p, 1"" and Xs.
Dimensions: Holotype: Length of cyst 71 μm, width of cyst 62 μm, length of processes up to 7 μm, width of paracingulum 9.5 μm. Other specimens: Length of cyst 62-71 μm, width of cyst 52-66 μm, length of processes up to 10 μm. Number of specimens measured: 10.
Occurrence: Rare to abundant in the Teradomari Formation and Shiiya Formation (Middle Miocene to Pliocene).
Remarks: This new species is characterized by the rounded hexagonal cyst body without an apical boss. The specimens obtained from the Niigata district are ill-preserved and corroded. This species is similar to Spiniferites cingulatus (O. WETZEL), but differs from the latter in having a hexagonal cyst body and shorter processes.
Taxonomic junior synonym: Spiniferites ovatus Bujak, according to Bujak and Matsuoka (1986, p.239).
Holotype: Matsuoka, 1983, pl.13, figs.1ab
Age: Middle-Late Miocene
-------------------------------------------------------------------------------------------------------------------------
Original description: [Matsuoka, 1983b]:
Spiniferites hexatypicus sp. nov.
PI. 13, figs. 1-3, Text-Fig. 18
Derivation of name: Greek, hexa + typicus, hexagonal shaped, with reference to the hexagonal cyst body.
Diagnosis: Cyst relatively long and rounded hexagonal, and having smooth to finely granular surface. Epicyst trapezoidal in shape, and hypocyst nearly trapezoidal in shape. Processes short, solid, gonal only and simple or small bifid distally. Proximal base of processes somewhat membraneous. Archeopyle simple precingular and formed by loss of the 3 paraplate.
Holotype: KMD slide NTE 3a-3 (8.3/134.7), pl. 13, fig. 1. Sample NTE 3a, Teradomari Formation - Middle to Late Miocene. Loc.: Teradomari, Teradomari-cho, Niigata Prefecture, Central Japan.
Description: The intermediate proximochorate cyst is rounded hexagonal in shape and consists of two layers, periphragm and endophragm adpressed between processes. The periphragm has a smooth to finely granular surface. The epicyst without apical boss shows a rounded trapezoidal shape. The hypocyst marks a trapezoidal outlne in equatorial view. The processes are composed of only short, solid and gonal type with simple or small bifurcate recurved distal extremities. The archeopyle is a simple precingular type derived from loss of the 3" paraplate. The paratabulation is represented by parasuture as the follow; 4', 0a, 6", 6c, 6'", 1p, 1"" and Xs.
Dimensions: Holotype: Length of cyst 71 μm, width of cyst 62 μm, length of processes up to 7 μm, width of paracingulum 9.5 μm. Other specimens: Length of cyst 62-71 μm, width of cyst 52-66 μm, length of processes up to 10 μm. Number of specimens measured: 10.
Occurrence: Rare to abundant in the Teradomari Formation and Shiiya Formation (Middle Miocene to Pliocene).
Remarks: This new species is characterized by the rounded hexagonal cyst body without an apical boss. The specimens obtained from the Niigata district are ill-preserved and corroded. This species is similar to Spiniferites cingulatus (O. WETZEL), but differs from the latter in having a hexagonal cyst body and shorter processes.