Back
Spiniferites pacificus
From Fensome et al., 2019:
Spiniferites pacificus Zhao Yunyun and Morzadec-Kerfourn, 1994, p.268–269, pl.1, figs.1a–c,2a–b,3; pl.2, figs.1–2,3a–b. Holotype: Zhao Yunyun and Morzadec-Kerfourn, 1994, pl.1, figs.1a–c. Age: Pleistocene.
---------------------------------------------------------------------------------------------------
Original description (Zhao Yunyun and Morzadec-Kerfourn, 1994):
SPINIFERITES PACIFICUS NOV. SP. : P1. 1, fig. 1-3 ; P1.2, fig. 1-3.
Derivatio nominis - From the Pacific Ocean.
Holotype - Leg 126, Site 791B, 742.87 m (sample 126-791B-38R-1, 7-9 cm) Slide A, L39, fig 6 P1. 1, Fig 1, deposited at the Institute of Geology of the University of Rennes.
Typicum locus - Leg 126, Site 791B, Izu-Bonin Region.
Typicus stratum - Lower to Upper Pleistocene.
Diagnosis - Proximochorate cyst of spherical to ovoid shape whose wall is composed of an endophragm and a periphragm with a microgranular surface. Presence of gonal processes with trifurcated then bifurcated ends, intergonal processes with bifurcated ends and two antapical processes, hollow, more developed than the others, connected by a low septal membrane and open at their ends divided into three long branches with bifurcated terminations.
Dimensions - Holotype: shell 25.6 x 28.8 µm, length of gonal processes: 7.6 µm, length of antapical processes: 12.8 µm. Average dimensions on 23 measured specimens: shell: 35.3 x 29.9 µm, length of gonal processes: 10.8 µm, length of antapical processes: 13.2 µm.
Description - The proximal chorionic cyst is subspherical to ovoid in shape. The wall consists of two layers, and the periphragm is adorned with microgranules clearly visible under SEM. The processes are hollow, straight, and rigid. Their base is wider than their apex. The gonial or intergonial processes are adorned with very fine or smooth microgranules. The gonial processes located in the region of the parasulcus and paracingulum have trifurcated and then bifurcated terminations. One process is intercalated between two gonial processes. The apex of this intergonial process is only bifurcated. The base of the processes is slightly enlarged and connected by a parasutural membrane. The two antapical processes are larger and thicker than the others. They are hollow, and their distal termination is open with trifurcated edges. Each of the branches is long and finely bifurcated. The base of these processes is broad and connected by a low membrane: Paratabulation is emphasized by low craters connecting the processes. The paratabulation is that of the genus Spiniferites: 3-4, 0a, 6", 6c, 5-6", lp, 1". The dorsal archeopyle has a pentagonal shape (3").
Discussion – The important specific characteristics of these cysts of the genus Spiniferites are the presence of intergonal processes and two strong dorsal antapical processes connected by a weakly developed membrane. Spiniferites pacificus nov. sp. is distinguished from Spiniferites buloideus (DEFLANDRE & COOKSON, 1955) SARJEANT, 1970 by its larger size, the presence of intergonal processes, and the stronger development of the dorsal antapical processes. S. pacificus nov. sp. differs from Spiniferites membranaceus (ROSSIGNOL, 1964) SARJEANT, 1970 by the presence of intergonal processes and a weaker development of the membrane connecting the two dorsal antapical processes. In S. membranaceus, the two antapical processes are fused by a substantial membrane up to their distal end. Spiniferites mirabilis (ROSSIGNOL, 1964) SARJEANT, 1970 is distinguished from S. pacificus nov. sp. by the presence, in general, of two intergonal processes between the gonals and by a more developed antapical complex composed of either 3 processes or 4 to 6- or more- processes connected by a membrane developed to the end of the processes. The species illustrated by Matsuoka (1992, Pl.1, fig. 4) under the name Spiniferites sp. cf. delicatus REID, 1974 from recent sediments off the coast of Japan is very close to S. pacificus nov. sp. Similarly, the species illustrated by McMinn (1992, Pl.1, Fig 5-7) under the name Spiniferites mirabilis (ROSSIGNOL, 1964) SARJEANT, 1970 and from Pliocene to Holocene sediments of the Gippsland Basin in Australia is to be related to Spiniferites pacificus nov. sp.
Spiniferites pacificus Zhao Yunyun and Morzadec-Kerfourn, 1994, p.268–269, pl.1, figs.1a–c,2a–b,3; pl.2, figs.1–2,3a–b. Holotype: Zhao Yunyun and Morzadec-Kerfourn, 1994, pl.1, figs.1a–c. Age: Pleistocene.
---------------------------------------------------------------------------------------------------
Original description (Zhao Yunyun and Morzadec-Kerfourn, 1994):
SPINIFERITES PACIFICUS NOV. SP. : P1. 1, fig. 1-3 ; P1.2, fig. 1-3.
Derivatio nominis - From the Pacific Ocean.
Holotype - Leg 126, Site 791B, 742.87 m (sample 126-791B-38R-1, 7-9 cm) Slide A, L39, fig 6 P1. 1, Fig 1, deposited at the Institute of Geology of the University of Rennes.
Typicum locus - Leg 126, Site 791B, Izu-Bonin Region.
Typicus stratum - Lower to Upper Pleistocene.
Diagnosis - Proximochorate cyst of spherical to ovoid shape whose wall is composed of an endophragm and a periphragm with a microgranular surface. Presence of gonal processes with trifurcated then bifurcated ends, intergonal processes with bifurcated ends and two antapical processes, hollow, more developed than the others, connected by a low septal membrane and open at their ends divided into three long branches with bifurcated terminations.
Dimensions - Holotype: shell 25.6 x 28.8 µm, length of gonal processes: 7.6 µm, length of antapical processes: 12.8 µm. Average dimensions on 23 measured specimens: shell: 35.3 x 29.9 µm, length of gonal processes: 10.8 µm, length of antapical processes: 13.2 µm.
Description - The proximal chorionic cyst is subspherical to ovoid in shape. The wall consists of two layers, and the periphragm is adorned with microgranules clearly visible under SEM. The processes are hollow, straight, and rigid. Their base is wider than their apex. The gonial or intergonial processes are adorned with very fine or smooth microgranules. The gonial processes located in the region of the parasulcus and paracingulum have trifurcated and then bifurcated terminations. One process is intercalated between two gonial processes. The apex of this intergonial process is only bifurcated. The base of the processes is slightly enlarged and connected by a parasutural membrane. The two antapical processes are larger and thicker than the others. They are hollow, and their distal termination is open with trifurcated edges. Each of the branches is long and finely bifurcated. The base of these processes is broad and connected by a low membrane: Paratabulation is emphasized by low craters connecting the processes. The paratabulation is that of the genus Spiniferites: 3-4, 0a, 6", 6c, 5-6", lp, 1". The dorsal archeopyle has a pentagonal shape (3").
Discussion – The important specific characteristics of these cysts of the genus Spiniferites are the presence of intergonal processes and two strong dorsal antapical processes connected by a weakly developed membrane. Spiniferites pacificus nov. sp. is distinguished from Spiniferites buloideus (DEFLANDRE & COOKSON, 1955) SARJEANT, 1970 by its larger size, the presence of intergonal processes, and the stronger development of the dorsal antapical processes. S. pacificus nov. sp. differs from Spiniferites membranaceus (ROSSIGNOL, 1964) SARJEANT, 1970 by the presence of intergonal processes and a weaker development of the membrane connecting the two dorsal antapical processes. In S. membranaceus, the two antapical processes are fused by a substantial membrane up to their distal end. Spiniferites mirabilis (ROSSIGNOL, 1964) SARJEANT, 1970 is distinguished from S. pacificus nov. sp. by the presence, in general, of two intergonal processes between the gonals and by a more developed antapical complex composed of either 3 processes or 4 to 6- or more- processes connected by a membrane developed to the end of the processes. The species illustrated by Matsuoka (1992, Pl.1, fig. 4) under the name Spiniferites sp. cf. delicatus REID, 1974 from recent sediments off the coast of Japan is very close to S. pacificus nov. sp. Similarly, the species illustrated by McMinn (1992, Pl.1, Fig 5-7) under the name Spiniferites mirabilis (ROSSIGNOL, 1964) SARJEANT, 1970 and from Pliocene to Holocene sediments of the Gippsland Basin in Australia is to be related to Spiniferites pacificus nov. sp.