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Subspecies Globorotalia (Globorotalia) hirsuta hirsuta d'Orbigny 1839 | ||||||
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| Diagnosis / Definition: | ||||||
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Blow (1969): Description of neotype: Test large, coiled in a low trochospire consisting of about 9-io chambers in the spire and with 4 complete chambers in the last whorl; a small portion of the fifth chamber is just visible especially ventrally. The equatorial profile is strongly lobulate and the axial profile shows a biconvex test with a sub-acute peripheral margin which bears a distinct carina. The dorsal surface of the test is smoothly convex, almost dome-like, and the earlier part of the test is considerably above the level of the peripheral parts of the chambers of the last whorl but the earlier spire is not raised. The dorsal surfaces of the chambers are not individually inflated and the chambers are not embracing. The dorsal intercameral sutures are smoothly recurved and weakly limbate at least for the intercameral sutures of the last two chambers; this dorsal limbation is only clearly visible when the surface of the test is examined under water. Ventral surfaces of the chambers distinctly inflated and the ventral intercameral sutures incised, distinct and slightly curved to slightly sinuous in disposition. Umbilicus small, but open and deeply set between the ventral umbilical shoulders of the opposing chambers. Umbilicus partly overhung by a lobe like extension of the last chamber which is strongly inflated ventrally. Aperture, interiomarginal, umbilical extraumbilical, a slit like opening extending from within the open umbilicus almost to the peripheral margin and bordered by a thin narrow lip. Wall, calcareous, radial hyaline [62a], densely but finely perforate without distinct pore pits. Wall , pustulose, especially over the dorsal surfaces of the earlier chambers and over the ventral surfaces of the chambers prior to the last; pustules well separated not fused together so giving a coarsely "hispid" appearance but this "hispidity" does not appear to be due to the presence of spine bases. Maximum diameter of neotype 0.69 mm. |
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| Discussion / Comments: | ||||||
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Blow (1969): General Notes: A considerable number of authors have, in the identification of this taxon, followed the concept developed by BRADY for "Pulvinulina canariensis (D'ORBIGNY)" using the binomen "Globorotalia canariensis (D'ORBIGNY)." However as discussed by BANNER and BLOW (196o, Contrib. Cushman Found. Foram. Res., vol. XI, pt. 1, PP. 33-34) a syntypic series of two specimens exists for Rotalina canariensis D'ORBIGNY. The two syntypes are badly damaged but both specimens are non-carinate and as such can be seen to be referable to Globorotalia (Turborotalia). With the selection of one of the two syntypes as a lectotype, and following the discussion given by BANNER and BLOW (Op. Cit. supra), it can now be justifiably argued that Rotalina canariensis should be regarded as specifically nomen dubium at least. However, the lectotype and single remaining syntype are sufficient to show that D'ORBIGNY'S concept of canariensis was distinctly different from BRADY'S subsequently developed concept. D'ORBIGNY clearly figured a form, called by him Rotalina hirsuta, with a depressed, flattened and carinate test. It seems clear from the description given by D'ORBIGNY that he was dealing with the same morphotype subsequently called P. canariensis by BRADY. It should be noted that BRADY'S morphotype is quite common in the material Collected by H.M.S. Challenger from the vicinity of the Canary Islands and these specimens are virtually topotypic for Rotalina hirsuta D'ORBIGNY, 1839. As noted by BANNER and BLOW (op. cit. supra, p. 37), no syntypes exist in the ALCIDE D'ORBIGNY collections in Paris and, therefore, a neotype is proposed here from the material collected by H.M.S. Challenger. The neotype is proposed from material Collected by H.M.S. Challenger at Station no. 8, off Gomera, Canary Islands; the neotype is deposited in the British Museum (Natural History) registered number 1968-3-27 (ex sample ZF.461). The justification for clearly and objectively defining the morphology of G. (G.) hirsuta hirsuta by neotypy is now to be seen in the recent taxonomic recognition of such taxa as Globorotalia margaritae BOLLi and Globorotalia (G.) crassula viola BLOW, n.subsp., as well as the biostratigraphic need to carefülly distinguish the morphological limits of the taxon in the fossil record. Differential diagnosis between G. (G.) hirsuta hirsuta and forms such as these mentioned here can only be validly made when there exists a single primary reference type to which objective reference can be made. Remarks: G. (G.) hirsuta hirsuta is characterized by a comparatively lax coiling mode and a spire which tends to show flare. The chambers are not embracing. Ventrally, the taxon shows a normally convex ventral surface with a small but deeply set open umbilicus. Forms now referred to Globorotalia (G.) crassula viola have been confused with G. (G.) hirsuta hirsuta and/or G. (G.) hirsuta praehirsuta. However, G. (G.) hirsuta (sensu lato) possesses a strongly convex (almost "domed") dorsal surface but the dorsal surfaces of the chambers are not individually inflated. Further, the dorsal intercameral sutures are smoothly recurved so giving a virtual hemicircular appearance to the chambers in dorsal aspect; the dorsal intercameral sutures are only weakly limbate. All these characters distinguish G. (G.) hirsuta (sensu lato) from G. (G.) crassula viola which has a nearly flat dorsal surface, strongly limbate dorsal sutures which are nearly straight or only slightly curved. The dorsal arrangement of the chambers in G. (G.) crassula viola gives a mitred, champered or "dove tailed" appearance to the test in dorsal aspect similar to the petal arrangement of the violet (e.g., Viola odorata) from which the subspecific name was taken. G. (G.) hirsuta hirsuta differs from G. (G.) hirsuta praehirsuta in having a more inflated ventral surface to the final chamber, in having a more lax coiling mode which is expressed ventrally in the presence of a small, open but deeply set umbilicus, and in having less closely appressed, less embracing chambers as seen in dorsal aspect. The surfaces of test in hirsuta (sensu stricto) are more pustulose than in praehirsuta Stratigraphical Range: From within the early part of Zone N.22 to Zone N.23. The neotype was obtained from Recent or Subrecent deposits,Challenger Station No.8, off Gomera, Canary Islands, from a dredge sample taken in 62o fathoms. Specimen from a sample registered in the British Museum (Natural History) as ZF.461. |
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| Synonym list: | ||||||
| Blow (1969): 1839 Rotalina hirsuta d'Orbigny. - d'Orbigny : p.131 pl. 1, figs. 37-39
non 1839 Globigerina hirsuta d'Orbigny. - d'Orbigny : pl. 2, figs. 4-6
1884 Pulvinulina canariensis d'Orbigny. - Brady : p.692 pl. 103, figs. 8a-10b
non 1960 Rotalina canariensis d'Orbigny. - Banner & Blow : p.692 pl. 103, figs. 8a-0b
1969 Globorotalia (Globorotalia) hirsuta hirsuta d'Orbigny. - Blow : p.398 pl. 8, figs. 1-3; pl. 43, figs. 1-2
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| Was used in synonym list of: | ||||||
| References: | ||||||
d'Orbigny,A.D. (1839): Brady,H.B. (1884): Banner,F.T. and Blow,W.H. (1960): Blow,W.H. (1969): |
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| Anonymous: Unedited TaxonConcept data | ||||||
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