Catalog - Globigerina inflata

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Globigerina inflata

Citation: Globigerina inflata d’Orbigny, 1839

Type specimens: 1966.2.3.23 - neotype; ZF461 - neotype sample.

Type locality: Holotype: marine sands off Santa Cruz, Teneriffe, Canary Islands Neotype: Sample dredged by H. M. S. Challenger on 12th February, 1873, at Station 8, off Gomera, Canary Islands (28° 3' 15" N. lat., 7° 27' 00" W. long.) at 620 fathoms (378 metres) submarine depth. The sample is catalogued in the British Museum (Natural History), London, as ZF461.

HOLOTYPE description: Testa suborbiculata, globosa, punctala, lucida, alba; spira brevi, obtusa, anfractibus duobus, partim amplexantibus; loculis quatemis, convexis; suturis minime excavatis; apertura magna. [d'Orbigny 1839]

Coquille.- Orbiculaire,très-convexe,presque sphérique, presqu'aussi haute que large, légèrement marquée de petits points ou trous, qui ne l'empêchent par d'être brillante. Spire peu convexe, très-obtuse, en partie recou- verte par le retour des loges, composée de deux tours peu distincts au sommet, ou de sept à huit loges en tout. Loges globuleuses peu détachées les unes des autres, au nombre de quatre ail dernier tour; leurs sutures sont peu profondes, et leur jonction à angle droit au centre n'y laisse qu'une tres-légère dépression ombilicale. Ouverture unique, en croissant, très-longue, occupant presque toute la longueur de la dernière loge. Couleur blanche. [d'Orbigny 1839]

NEOTYPE description: the test of the neotype (plate 4, figure Ia-c) consists of approximately three whorls of chambers coiled in a low trochospire. The early whorls have five chambers in each whorl, but the last whorl possesses four chambers only. The test is almost wholly involute ventrally and almost wholly evolute dorsally. The chambers arc slightly inflated dorsally, relatively strongly inflated vcntrally, and subovoid in axial view, the axial profile being distinctly more convex ventrally than clorsally. The dorso-ventral periphery is broadly rounded in axial view and weakly lobulate in equatorial view. Dorsally, the initial sutures are indistinct (except when the test is clarified by liquids), but they become increasingly (although still shallowly) depressed at successive ontogenetic stages. The dorsal intercamcral sutures are curved and meet the spiral suture at broad angles. The early chambers, in dorsal view, are reniform in outline, but they become increasingly longer than broad during ontogeny. The later chambers also acquire greater breadth at their posterior than at their anterior ends. T he last-formed chamber slightly embraces the outcr part of the dorsalsurface ofthe penultimate whorl (plate 4, figure Ib). Ventrally, the intercameral sutures are distinctly but not strongly depressed, and arc subradial. They meet tlie periphery and the umbilicus at broad angles approaching right angles. The umbilicus is nar·row but open and deep; it is sharply delimited by the umbilical shoulders of the first three chambers of the last whorl and by the inner part of the apertural face of the last chamber. The aperture is a broad, high arch, interiomarginal, ventral and intraumbilical-extraumbilical in position, extending along the basal suture of the narrow, convex apertural face almost as far as its junction with the periphery of the penultimate whorl. The aperture possesses no distinct lip, but the apertural face is thickened, hyaline and granular above the aperture throughout its length. The walls of the test are uniformly perforate, but the perforations are superficially obscured in the early chambers by surface granularity, both dorsally and ventrally. The granularity is most marked, dorsally, on the surface of the early whorls, and, ventrally, in the area immediately around the umbilicus and immediately facing the aperture. The wall of the last-formed chamber is smooth, except on the apertural face. [Banner & Blow 1967]

Nous ne connaissons aucune autre espèce qu'on puisse confondre avec celle-ci par ses spires se recouvrant en dessus, sur plus de la moitié de la largeur des loges; c'est aussi la plus sphérique dans son ensemble, et l'une des moins ombiliquée." [d'Orbigny 1839]

Neotype designated by Banner & Blow 1967 with the following explanation:
Although d'Orbigny believed that this species could not be confused with any other globigerinid because of its globose test, in which the last-formed chambers partially embraced the previous whorl dorsally, and in which the umbilicus was greatly reduced, it is apparent that this species is not clearly separable, on its original diagnosis, from Pulleniatina obliquiloculata (sensu lato). As noted above, the two taxonomic groups have, in fact, sometimes been confused. In fact, although it has been consistently ignored in the literature, the diagnosis and description given by d'Orbigny for Globigerina inflata (""Spire peu convexe, tres obtuse, en partie recouverte par le retour des loges"") would agree with the diagnosis given for Pulleniatina by some authors (e.g., Sigal, 1952, p. 235).

In order to make an objective distinction possible between the taxa, it is necessary to typify Globigerina inflata d'Orbigny, 1839. However, a thorough search of the Alcide d'Orbigny collections has shown that none of the original syntype series exists (Banner and Blow, 1960a, p. 37). Accordingly, a neotype for Globigerina inflata d'Orbigny, 1839, is here proposed and described. As neotypified, G. inflata d'Orbigny belongs to the sub-genus Turborotalia Cushman and Bermudez, as was agreed by Bermudez (1961, p. 1323). It may be considered to be a subjective senior synonym of Rotalina aradasii Seguenza, 1862, originally obtained from the Pleistocene and Pliocene of Catania and Messina, but this cannot be determined with cenainty, as Seguenza's type series was destroyed during the Messina earthquake of 1908 (teste Mistretta, 1962), and R. aradasii does not appear to have been neotypified. Globigerina nipponica Asano, 1957, was distinguished from G. inflata d'Orbigny by its ""last, smaller chamber of which the apertural periphery has a distinct lip"" (Asano, 1957, p. 18). The original description and illustrations of G. nipponica (Asano, loc. cit. and pi. l , figs. 1-3) show that this taxon was based on specimens conspecific with Globorotalia ( T .) inflata, as neotypified, which possess small aborted final chambers. G. (T.) nipponica (Asano) may therefore be regarded as a junior synonym of G. (T.) inflata (d'Orbigny).

The name G. inflata has been extensively used. Ellis and Messina (1940) list 53 references to this name published before 1936, and since then there have been very many more. Significantly, Ellis and Messina list only four references which were published prior to Brady's illustrations (1884, pi. 79, figs. 8-10), and we have been able to find no others. As we believe it probable that the great majority of taxonomists have used Brady's description and illustrations as their basis for interpretation of d'Orbigny's taxon, we have selected as neotype a specimen which 1) came from a locality as near as possible to that from which d'Orbigny's specimens were obtained, 2) came from material studied by Brady, 3) satisfies the original diagnosis given by d'Orbigny, and 4) agrees with the concept of the species developed by Brady."

References:

Banner, F. T. & Blow, W. H. (1967). The origin, evolution and taxonomy of the foraminiferal genus Pulleniatina Cushman, 1927. Micropaleontology. 13(2): 133-162. gs

Blow, W. H. (1969). Late middle Eocene to Recent planktonic foraminiferal biostratigraphy. In, Bronnimann, P. & Renz, H. H. (eds) Proceedings of the First International Conference on Planktonic Microfossils, Geneva, 1967. E J Brill, Leiden 380-381. gs

d'Orbigny, A. (1839b). Foraminifères des Iles Canaries. In, Barker-Webb, P. & Berthelot, S. (eds) Histoire naturelle des Iles Canaries. (2): 120-146. gs

CATALOG OF ORIGINAL DESCRIPTIONS: Globigerina inflata d’Orbigny, 1839

Globigerina inflata

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