Verticillata hexacantha |
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Verticillata hexacantha differs from Pteroscenium pinnatum
Richard N. Benson (21/01/2004) |
Popofsky’s illustration (1913, p. 282-283, text-fig. 11) of Verticillata hexacantha
is more realistic of the actual taxon from the Gulf of California than is Haeckel’s (1887, p. 1152; pl. 53, figs. 14-16) artistic version of Pteroscenium pinnatum. They may be the same species; if so, Haeckel’s name has priority, but Popofsky (1913) erected the new genus Verticillata with V. hexacantha as the type species. He did not mention Haeckel’s species in his description. Campbell (1954, Treatise on Invertebrate Paleontology, Part D, Protista 3, p. D104 and D 118) lists the two type species separately.
Haeckel’s description and illustration of P. pinnatum differs from the Gulf of California species identified as Verticillata hexacantha in the following features: the surface of the cephalis of P. pinnatum is smooth, not spiny; a median bar is absent; the apical horn is conical, not three-bladed; there are no ribs shown in the cephalic wall; there is no vertical bar or spine; its total (shell) length is only 90 µm whereas the maximum length of the test of the Gulf species (including apical horn and fee) is 221-277 µm.
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