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Gonyaulacysta jurassica ssp. adecta var. adecta
From Fensome et al., 2019:
Gonyaulacysta jurassica ssp. adecta var. adecta (Sarjeant, 1982b). Autonym. Holotype: Sarjeant, 1982b, pl.1, fig.2. Age: Callovian.
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Original description (Sarjeant, 1982b):
Gonyaulacysta jurassica (DEFLANDRE) subsp. adecta nov.
Pls. 1-3; pl. 4, figs. 1-4, 9; pl 6, figs. 4-5, 9.
DERIVATION OF NAME: Greek adektos, unbitten, unmolested.
DIAGNOSIS: A su bspecies of Gonyaulacysta jurassica in which no hypotractal cavation is developed. nor is an opisthopyle present.
HOLOTYPE: Specimen SWS 2459/1/6, slide GMUS Pd 249; figured herein, pl. 1, fig. 2. (Lodged in the collections of the Department of Geological Sciences, University of Saskatchewan, Canada). Middle Jurassic (Callovian: Jason Zone), Isle of Skye, western Scotland.
PARATYPES: Specimens SWS 2459/1/134 and SwS 2459/1/138, slide GMUS Pd 249; figured herein, pl. 1, figs. 5, 6. Same locality and lodgement.
DIMENSIONS: Holotype: overall length 77 μm, length of epiperico el 20 μm, length of endoblast 50 um, overall breadth 62 μm, breadth of endoblast 45 um. Paratype A: overall length 57 μm, length of epipericoel 12 μm, length of endoblast 45 μm, overall breadth 37 μm, breadth of endoblast 31 μm.
Paratype B: overall length 79 μm, length of epipericoel 22 μm, length of endoblast 56 μm, overall breadth 51 μm, breadth of endoblast 43 μm. Range of dimensions: overall length 56-105 μm. 30 specimens measured.
DISCUSSION: Though both subspecies here distinguished are present together in the type horizon for the species, each has an independent history, G. jurassica subsp. adecta appearing in the Callovian and fading out in the Early Jurassic, G. jurassica subsp. jurassica developing from it in the early Oxfordian and persisting into the Middle or Late Kimmeridgian. Since each thus has not only an evolutionary but also a stratigraphical significance, nomenclatural separation appears justified despite their overlapping range.
Gonyaulacysta jurassica ssp. adecta var. adecta (Sarjeant, 1982b). Autonym. Holotype: Sarjeant, 1982b, pl.1, fig.2. Age: Callovian.
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Original description (Sarjeant, 1982b):
Gonyaulacysta jurassica (DEFLANDRE) subsp. adecta nov.
Pls. 1-3; pl. 4, figs. 1-4, 9; pl 6, figs. 4-5, 9.
DERIVATION OF NAME: Greek adektos, unbitten, unmolested.
DIAGNOSIS: A su bspecies of Gonyaulacysta jurassica in which no hypotractal cavation is developed. nor is an opisthopyle present.
HOLOTYPE: Specimen SWS 2459/1/6, slide GMUS Pd 249; figured herein, pl. 1, fig. 2. (Lodged in the collections of the Department of Geological Sciences, University of Saskatchewan, Canada). Middle Jurassic (Callovian: Jason Zone), Isle of Skye, western Scotland.
PARATYPES: Specimens SWS 2459/1/134 and SwS 2459/1/138, slide GMUS Pd 249; figured herein, pl. 1, figs. 5, 6. Same locality and lodgement.
DIMENSIONS: Holotype: overall length 77 μm, length of epiperico el 20 μm, length of endoblast 50 um, overall breadth 62 μm, breadth of endoblast 45 um. Paratype A: overall length 57 μm, length of epipericoel 12 μm, length of endoblast 45 μm, overall breadth 37 μm, breadth of endoblast 31 μm.
Paratype B: overall length 79 μm, length of epipericoel 22 μm, length of endoblast 56 μm, overall breadth 51 μm, breadth of endoblast 43 μm. Range of dimensions: overall length 56-105 μm. 30 specimens measured.
DISCUSSION: Though both subspecies here distinguished are present together in the type horizon for the species, each has an independent history, G. jurassica subsp. adecta appearing in the Callovian and fading out in the Early Jurassic, G. jurassica subsp. jurassica developing from it in the early Oxfordian and persisting into the Middle or Late Kimmeridgian. Since each thus has not only an evolutionary but also a stratigraphical significance, nomenclatural separation appears justified despite their overlapping range.