CATALOG OF ORIGINAL DESCRIPTIONS: Globotruncana putahensis Takayanagi 1965

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.


Higher levels: pf_cat -> G -> Globotruncana -> Globotruncana putahensis
Other pages this level: << < G. monmouthensis, G. morozovae, G. nakkadyi, G. naqibi, G. navarroensis, G. neotricarinata, G. orientalis, G. pessagnoi, G. postrugosa, G. poststephensoni, G. pozaryskae, G. pseudoconica, G. pseudofornicata, G. pura, G. pustulifera, G. putahensis, G. qabeliatensis, G. quadrata, G. renzi, G. repanda, G. riojai, G. roddai, G. rosetta insignis, G. rosetta pettersi, G. rugosa, G. rugosa subrugosa, G. sahakianae, G. samuriensis, G. schneegansi, G. semsalensis, G. sharawnaensis, > >>

Globotruncana putahensis

Citation: Globotruncana putahensis Takayanagi 1965
Rank: Species
Type locality: A depth of 70-76 feet in Shell Oil Company Diamond Core Hole No. SA, Section A, drilled along the Putah Creek on the Yolo-Solano County line, SW1/4 sec. 23, T. 8N., R. 4W., Yolo County, California.
Type age: Upper Cretaceous. Campanian, middle to upper part of the Globotruncana subcircwnnodifer Zone.
Type sample and level: Forbes Formation; rare.
Holotype Repository: Palo Alto, California; paleontological type collection of Stanford University.
Type & figured specimens: Holotype (fig. 2a-c) no. 9799.

Current identification/main database link: Globotruncanita elevata (Brotzen, 1934)


Original Description
Test medium in size, low trochospiral, spiral side nearly flat or slightly convex, umbilical side strongly convex; peripheral outline subcircular, peripheral margin moderately lobate, axial periphery subacute, with a double keel, often weakened and transformed into a faint narrow peripheral band in later chambers of last whorl; chambers hemispherical, elevated towards umbilical region, lunate in spiral view, strongly inflated on umbilical side, about 16 to 18 chambers arranged in three whorls on spiral side, early ones globular, inflated, later flattened, increasing gradually in size, usually six in last whorl, commonly obliquely overlapping earlier chambers; sutures on umbilical side slightly curved, generally depressed, somewhat incised about umbilicus between adumbilical extension of peripheral keels on earlier chambers of last whorl; sutures on spiral side curved, obliquely directed backwards, strongly raised, beaded; early chambers with two closely spaced beaded keels, one of which is located on umbilical side and becoming feeble on later chambers, transformed into faint narrow peripheral band on last and penultimate chambers; wall finely perforate, coarsely hispid to beaded on umbilical side, and especially in earlier chambers, spiral side smooth; primary aperture interiomarginal, umbilical; tegilla with accessory apertures not preserved in examined specimens; coiling of test predominantly dextral.

Size: Maximum diameter of holotype 0.46 mm., maximum thickness 0.25 mm.

Etymology: from the locality - Putah Creek

Extra details from original publication
Remarks. - The new species is very similar to Globotruncana wiedenmayeri wiedenmayeri Gandolfi (1955) in general appearance, but it differs in lacking rugose ridges on the umbilical side and 'arched lips (rosetta type) covering the umbilical apertures'. Furthermore G. wiedenmayeri wiedenmayeri has finely raised double keel throughout the whole chamber margins. In this respect the present form is more similar to G. wiedenmayeri magdalenaensis Gandolfi (1955, op. cit.), but it is also distinguished from the latter form in having generally six chambers in the last whorl, in contrast to four to five of the latter subspecies, distinctly beaded sutures on the spiral side, and relatively sharp angle at axial periphery. Nevertheless, some morphological characters as shape of chamber, nature of double keel, and roughness of chamber surface on the umbilical side suggests a close relationship among these three forms. However, according to Berggren (1962) who examined the holotypes of Gandolfi's two subspecies, these are considered to be synonymous with Globotruncana fundiconulosa Subbotina (1953 pl. 14, figs. la-3c (not 4a-c)). And he emphasized 'the acute circum-umbilical rim (and the broad slope of the chambers towards the umbilical region) and scalloped chambers (and raised sutures) on the spiral side' as diagnostic to this form. Further, Globotruncana (Globotruncana) ventricosa carinata Dalbiez (1955) seems to be synonymous with G. fundiconulosa, so far as their illustrations and descriptions are concerned. Employing these criteria, G. putahensis can be distinguished from G. fundiconulosa. An Australian form referred to Globotruncana (Globotruncana) elevata elevata (Brotzen) by Edgell (op cit. ) and the Californian form illustrated by Graham and Church (op. cit.) under the name of G. elevata elevata (Brotzen) appear to be identical with G. putuhensis. Concerning the Australian specimens, Edgell noted that in the earlier chambers of some specimens there is a tendency toward a doubtful second keel. On the illustrations by Edgell and/or Graham and Church, such kind of second beaded keels are clearly shown on the earlier chan1bcrs on the umbilical side. These features are believed to suggest the presence of definite double keels on the chambers of the earlier whorls just as in G. putahensis. Such characteristic feature as a double keel was, however, not noticed by Brotzen (1934). Jn addition, Pessagno (1960) showed excellent thin sections of G. (G.) stuarti elevata (= G. elevata e!evata of authors), in which a single-keeled nature or the peripheral margin is clearly visible throughout its ontogenetic development. Taking these features into consideration, the present writer agrees with Pessagno's determination, and thus regards both Australian and Californian forms as distinct from G. elevata elevata (Brotzen). In the feature of the characteristic tendency or two closely spaced keels which fuse into a single keel, G. putahensis resembles Globotruncana rosetta (Carsey). But G. putahensis differs from the latter species and its allied forms in lacking a distinct peri-umbilical collar-like rise formed by the adumbilical extension of the peripheral keels and in having beaded umbilical surface. 1t is also similar to Globotruncana gansseri Bolli in general outline of test, shape of chamber, and roughened umbilical surface. But the latter exhibits G. putahensis appears to be taxonomically intermediate between G. rosetta and G. gansseri, in position.

References:

Takayanagi, Y. (1965). Upper Cretaceous planktonic foraminifera from the Putah Creek subsurface section along the Yolo-Solano County Line, California. Science Reports of the Tohoku University. 36(2): 161-237. gs :: ::


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Globotruncana putahensis compiled by the pforams@mikrotax project team viewed: 29-5-2020

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