Back
Spiniferites firmus
Spiniferites firmus Matsuoka, 1983
Holotype: Matsuoka, 1983b, pl.14, figs.5a–c; He Chengquan et al., 2009, pl.131, fig.14.
Age: Early Pleistocene
-------------------------------------------------------------------------------------------------------------------------------
Original description: [Matsuoka, 1983b]:
Spiniferites firmus sp. nov.
PI. 14, figs. 4, 5
Derivation of name: Latin, firmus, stout, with reference to the stout processes.
Diagnosis: Subspherical to ovoidal cyst having finely granular wall. Processes gonal only, stout, slightly tapering, mainly trifurcate and bifid distally. Archeopyle simple precingular and derived from the 3" paraplate.
Holotype: KMD slide NHA 11-3 (6.1/13 1.2), pl. 14, fig. 5. Sample NHA 11, Haizume Formation - Early Pleisto cene. Loc.: Hachioji, Oguni-cho, Niigata Prefecture, Central Japan.
Description: The proximochorate cyst is subspherical to ovoidal in shape and consists of two layers, periphragm and endophragm adpressed between processes. The surface of the periphragm is finely granular. The stout processes are slightly tapering and composed of gonal type only. Their distal extremities are bifid. The proximal base of the processes becomes membraneous and faintly granular. The parasutural septa are occasionally formed by incomplete membrane on the dorsal side in the antapical area. The precingular archeopyle is indicated by loss of the 3" paraplate. The paratabulation is typical of the genus.
Dimensions: Holotype: Length of cyst 55 μm, width of cyst 50 μm, length of processes 21 μm, width of paracingulum 7.0 μm. Other specimens: Length of cyst 40-45 μm, width of cyst 38-50 μm, length of processes 16-23 μm. Number of specimens measured: 15.
Occurrence: Rare to common in the Shiiya Formation, Nishiyama Formation and its equivalent formations and Haizume Formation (Late Miocene to Early Pleistocene).
Remarks: This new species is similar to Spiniferites membranaceus (ROSSIGNOL), but differs from the latter in having weak development of the membraneous parasutural septa at the antapical area and a larger cyst body, and also differs from S. pachydermus (ROSSIGNOL) in possessing tapering and somewhat membraneous processes S. firmus is different from S. pseudofurcatus (KLUMPP) in having a smaller cyst body and processes without any foliate distal extremities, and from S. pseudofurcatus var. obliqus (WALL) in possessing no processes with delicate
membraneous distal flare.
Holotype: Matsuoka, 1983b, pl.14, figs.5a–c; He Chengquan et al., 2009, pl.131, fig.14.
Age: Early Pleistocene
-------------------------------------------------------------------------------------------------------------------------------
Original description: [Matsuoka, 1983b]:
Spiniferites firmus sp. nov.
PI. 14, figs. 4, 5
Derivation of name: Latin, firmus, stout, with reference to the stout processes.
Diagnosis: Subspherical to ovoidal cyst having finely granular wall. Processes gonal only, stout, slightly tapering, mainly trifurcate and bifid distally. Archeopyle simple precingular and derived from the 3" paraplate.
Holotype: KMD slide NHA 11-3 (6.1/13 1.2), pl. 14, fig. 5. Sample NHA 11, Haizume Formation - Early Pleisto cene. Loc.: Hachioji, Oguni-cho, Niigata Prefecture, Central Japan.
Description: The proximochorate cyst is subspherical to ovoidal in shape and consists of two layers, periphragm and endophragm adpressed between processes. The surface of the periphragm is finely granular. The stout processes are slightly tapering and composed of gonal type only. Their distal extremities are bifid. The proximal base of the processes becomes membraneous and faintly granular. The parasutural septa are occasionally formed by incomplete membrane on the dorsal side in the antapical area. The precingular archeopyle is indicated by loss of the 3" paraplate. The paratabulation is typical of the genus.
Dimensions: Holotype: Length of cyst 55 μm, width of cyst 50 μm, length of processes 21 μm, width of paracingulum 7.0 μm. Other specimens: Length of cyst 40-45 μm, width of cyst 38-50 μm, length of processes 16-23 μm. Number of specimens measured: 15.
Occurrence: Rare to common in the Shiiya Formation, Nishiyama Formation and its equivalent formations and Haizume Formation (Late Miocene to Early Pleistocene).
Remarks: This new species is similar to Spiniferites membranaceus (ROSSIGNOL), but differs from the latter in having weak development of the membraneous parasutural septa at the antapical area and a larger cyst body, and also differs from S. pachydermus (ROSSIGNOL) in possessing tapering and somewhat membraneous processes S. firmus is different from S. pseudofurcatus (KLUMPP) in having a smaller cyst body and processes without any foliate distal extremities, and from S. pseudofurcatus var. obliqus (WALL) in possessing no processes with delicate
membraneous distal flare.