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Spiniferella granulata
Holotype. Plate 4, figure 9; GSCA slide no. P51199-02 (¼GSCC slide no. P5205-92G), 15.5x91.0; EF M56/1; Nunavut Palaeontology Collection no. NUPB 1019; Q section, Twosnout creek, Bylot Island. Bylot Island formation.
Etymology. The epithet is an adjective derived from the Latin granulatum, meaning small seed or grain, in reference to the nature of the ornamentation on the central body.
Diagnosis. A species of Spiniferella with an extremely long apical process, especially characterised by the strongly granular nature of the wall of the central body. Processes other than the apical are slender, tapering and have delicate, elongate trifurcations at the distal extremities.
Comments. Spiniferites scabrosus and an undescribed species of Achomosphaera, both of which have strongly granular ornamentation on the central body, occur in the Upper Cretaceous rocks of Bylot Island. The granulation is reminiscent of that in Spiniferites scabrosus, in both size and the distribution over the whole central body. Spiniferella crouchiae is much larger than Spiniferella granulata, having a central body that is 70–80um and an overall size of 125–150um, whereas Spiniferella granulata has a central body 36–63um long and 33–46um wide. Furthermore, the ornamentation of the central body of Spiniferella crouchiae can be smooth to granulate or reticulate; that of Spiniferella granulata is always markedly granulate. Although Sluijs and Brinkhuis (2024) do not include the sizes of the processes in Spiniferella crouchiae, the processes of Spiniferella granulata are clearly considerably slenderer and shorter. According to Sluijs and Brinkhuis (2024, 457), Spiniferella crouchiae has a smooth to granulate to reticulate autophragm. However, Spiniferella crouchiae is considerably larger than Spiniferella granulata, having a central body that is 70 to 80um and an overall dimension of 125 to 150um.
Size. Holotype: overall length 79um, overall width 55um, main body length 44um, main body width 33um, processes up to 10um long with trifurcations up to 6um long, apical process 23um long. Range of five specimens: overall length 58–94um, overall width 44–68um, central body length 36– 63um, central body width 33–46um, process length up to 15um, process width up to 4um, apical process length up to 28um and width up to 3.5um.
Age. Santonian to late Maastrichtian.
Etymology. The epithet is an adjective derived from the Latin granulatum, meaning small seed or grain, in reference to the nature of the ornamentation on the central body.
Diagnosis. A species of Spiniferella with an extremely long apical process, especially characterised by the strongly granular nature of the wall of the central body. Processes other than the apical are slender, tapering and have delicate, elongate trifurcations at the distal extremities.
Comments. Spiniferites scabrosus and an undescribed species of Achomosphaera, both of which have strongly granular ornamentation on the central body, occur in the Upper Cretaceous rocks of Bylot Island. The granulation is reminiscent of that in Spiniferites scabrosus, in both size and the distribution over the whole central body. Spiniferella crouchiae is much larger than Spiniferella granulata, having a central body that is 70–80um and an overall size of 125–150um, whereas Spiniferella granulata has a central body 36–63um long and 33–46um wide. Furthermore, the ornamentation of the central body of Spiniferella crouchiae can be smooth to granulate or reticulate; that of Spiniferella granulata is always markedly granulate. Although Sluijs and Brinkhuis (2024) do not include the sizes of the processes in Spiniferella crouchiae, the processes of Spiniferella granulata are clearly considerably slenderer and shorter. According to Sluijs and Brinkhuis (2024, 457), Spiniferella crouchiae has a smooth to granulate to reticulate autophragm. However, Spiniferella crouchiae is considerably larger than Spiniferella granulata, having a central body that is 70 to 80um and an overall dimension of 125 to 150um.
Size. Holotype: overall length 79um, overall width 55um, main body length 44um, main body width 33um, processes up to 10um long with trifurcations up to 6um long, apical process 23um long. Range of five specimens: overall length 58–94um, overall width 44–68um, central body length 36– 63um, central body width 33–46um, process length up to 15um, process width up to 4um, apical process length up to 28um and width up to 3.5um.
Age. Santonian to late Maastrichtian.