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Rottnestia amphicavata
Rottnestia amphicavata Dobell and Norris in Harland et al., 1980
Tax. jr. synonym of Spiniferites frigidus Harland and Reid in Harland et al., 1980, according to Bujak, 1984; however, de Vernal et al., 1992 retained Rottnestia amphicavata as a separate species.
Holotype: Harland et al., 1980, text-figs.4A-C
Age: Holocene
Original description (Harland et al., 1980)
Description. This variety is similar to R. amphicavata amphicavata sp. and bar. nov. but lacks the distinctive pair of antapical pericoels characteristic of the latter. The antapical extension is not invaginated; thus only one large antapical pericoel is present (height 18µm, width 25 µm). Two hydropyles are present in the right and left posterior portion of the antapical extension and connect the one large pericoel to the exterior. The sutural ridges and crests on the periphragm and the tabulation are similar to R. amphicavata. Dimensions. Length 56 µm, width 38 µm, overall length 88 µm. Remarks. This variety rather closely resembles R. borussica (Eisenack) Cookson & Eisenack. However, the apical extension does not narrow distally nor does it have an apical horn. The antapical extension has longitudinal folds which R. borussica lacks. The presence of a single large pericoel with two hydropyles in the antapical extension also helps separate these two species.
Tax. jr. synonym of Spiniferites frigidus Harland and Reid in Harland et al., 1980, according to Bujak, 1984; however, de Vernal et al., 1992 retained Rottnestia amphicavata as a separate species.
Holotype: Harland et al., 1980, text-figs.4A-C
Age: Holocene
Original description (Harland et al., 1980)
Description. This variety is similar to R. amphicavata amphicavata sp. and bar. nov. but lacks the distinctive pair of antapical pericoels characteristic of the latter. The antapical extension is not invaginated; thus only one large antapical pericoel is present (height 18µm, width 25 µm). Two hydropyles are present in the right and left posterior portion of the antapical extension and connect the one large pericoel to the exterior. The sutural ridges and crests on the periphragm and the tabulation are similar to R. amphicavata. Dimensions. Length 56 µm, width 38 µm, overall length 88 µm. Remarks. This variety rather closely resembles R. borussica (Eisenack) Cookson & Eisenack. However, the apical extension does not narrow distally nor does it have an apical horn. The antapical extension has longitudinal folds which R. borussica lacks. The presence of a single large pericoel with two hydropyles in the antapical extension also helps separate these two species.