Alicantina lozanoi


Classification: pf_cenozoic -> Truncorotaloididae -> Alicantina -> Alicantina lozanoi
Sister taxa: A. prolata, A. lozanoi,

Taxonomy

Citation: Alicantina lozanoi (Colom 1954)
Rank: Species
Basionym: Globigerina lozanoi Colom 1954
Synonyms:
Taxonomic discussion: Colom (1954) produced a plate with 48 outline drawings of his species lozanoi but did not identify one of these as a holotype. They include a rather wide range of morphologies, from relatively low-spired forms usually with 4-4½ chambers in the final whorl, interpreted as juveniles, to more high-spired forms with five to six chambers. Blow (1979) selected one of these, a specimen with 6 chambers, as a lectotype (Colom, 1954, pl. 2, fig. 45). Colom (1954) described Globigerina aspensis (= Acarinina aspensis) from the same locality as lozanoi. Both species are loosely coiled with a large, open umbilicus and have a similar number of chambers in the final whorl but lozanoi is smaller in size and high spired, whereas aspensis is larger and very low spired. The wall of aspensis was described as having pustules and the wall of lozanoi was described as smooth. Since Colom did not designate any type specimen(s) and his material is said to be in his personal collections and may, in fact, be lost, it is difficult to assess the two species from Colom’s illustrations alone. However, we have been able to examine well preserved material from various localities of both taxa and although the two morphotypes were described from the same locality and have similar short stratigraphic ranges they appear to be unrelated as can be seen from comparison of surface wall texture, chamber shape and apertural disposition.
Bolli (1957b) described Globigerina prolata from the Morozovella formosa formosa Zone (= E5). Hillebrandt (1976) was of the opinion that G. prolata was ancestral to G. nuttalli, whereas Blow (1979) regarded G. prolata as a subspecies of G. lozanoi. Blow (1979) figured a series of specimens (his pl. 145, figs. 1-5) to illustrate the complete gradation of the prolata morphotype into the lozanoi morphotype. However, the holotype of prolata is very poorly preserved and appears to be mostly an internal mould. Globigerina prolata has not been identified by many workers and, in fact, Tourmarkine and Luterbacher (1985) did not include it in their treatment of Paleocene and Eocene planktonic foraminifera. This would seem to indicate uncertainty over the validity of this morphotype. We think it is prudent not to use this morphotype until its taxonomic status is clarified. [Berggren et al. 2006]


This taxon was exhaustively discussed in the Atlas of Eocene Planktonic Foraminifera by Berggren et al. (2006a, p. 397–398) under Praemurica? lozanoi (see synonymy). Blow (1979), besides selecting a lectotype ( = n.45, pl. 2), indicates that out of Colom’s type plate 2, the specimens illustrated at no. 2, 8, 10–12, 14, 16–29, 31–32, 40–42, 44, 46–47 can be assigned to typical lozanoi lozanoi. Furthermore, after having identified lozanoi prolata specimens (see above), Blow (1979) also indicated which specimens he considered as transitional between the two subspecies. We totally agree with Blow’s choice and contrary to Berggren et al. (2006a), we consider A. prolata Bolli as a distinct taxon deserving recognition as a valid species (see above). [Soldan et al. 2018]

Catalog entries: Globigerina lozanoi

Type images:

Distinguishing features: Moderately high, evolute, trochospiral test, 5-6 globular chambers in final whorl; predominantly, intraumbilical aperture.

NB These concise distinguishing features statements are used in the tables of daughter-taxa to act as quick summaries of the differences between e.g. species of one genus.
They are being edited as the site is developed and comments on them are especially welcome.

Description


Diagnostic characters: This species is characterized by its medium high, relaxed (evolute) trochospire late in ontogeny, five to six globular chambers in the outer whorl, subcircular equatorial periphery and (predominantly, but not exclusively) intraumbilical aperture. [Berggren et al. 2006]

Wall type: Smooth, cancellate, nonspinose. [Berggren et al. 2006]

Test morphology: Test trochospiral, asymmetrically biconvex; the first two whorls coiled in medium high, tight spire then the coiling mode tends to become more evolute and the more evolute spire increases markedly in height; chambers globular, increasing gradually in size as added, 5 to 6 (more typically 6) in the last whorl; the last chamber in some instances more oval on the umbilical side; equatorial periphery subcircular, moderately lobate; sutures depressed, mainly straight and radial on both sides; umbilicus medium-sized and deep; aperture a distinct, moderately high arch, interiomarginal, umbilical; in specimens characterized by more oval last chamber the aperture tends to extend extraumbilically. [Berggren et al. 2006]

Size: 0.35-0.40 mm and a height of 0.45 mm (Colom, 1954). [Berggren et al. 2006]

Character matrix

test outline:Subcircularchamber arrangement:Trochospiraledge view:Inequally biconvexaperture:Umbilical-extraumbilical
sp chamber shape:Globularcoiling axis:Moderateperiphery:N/Aaperture border:N/A
umb chbr shape:Globularumbilicus:Narrowperiph margin shape:Broadly roundedaccessory apertures:None
spiral sutures:Strongly depressedumb depth:Deepwall texture:Cancellateshell porosity:Finely Perforate: 1-2.5µm
umbilical or test sutures:Strongly depressedfinal-whorl chambers:5.0-6.0 N.B. These characters are used for advanced search. N/A - not applicable

Biogeography and Palaeobiology


Geographic distribution: Cosmopolitan, more common in mid- to low latitudes. [Berggren et al. 2006]
Aze et al. 2011 summary: Low to middle latitudes; based on Berggren et al. (2006a)

Isotope paleobiology: No data available. [Berggren et al. 2006]
Aze et al. 2011 ecogroup 2 - Open ocean mixed-layer tropical/subtropical, without symbionts. Based on δ13C lighter than species with symbionts; also with relatively light δ18O. Sources cited by Aze et al. 2011 (appendix S3): Pearson et al. (2001a)

Phylogenetic relations: Although Hillebrandt (1976) and Blow (1979) regarded prolata as phylogenetically or ontogenetically linked to lozanoi. Blow stated (1979, p. 855) that the origin of G. lozanoi (sensu lato) was unknown, but that inasmuch as prolata morphotypes appear earlier in the succession that the ancestor of the lozanoi group was essentially a “four-chambered last-whorl turborotaliid morphotype.” Assignment to Turborotalia (as delineated here) is clearly not possible owing to the different wall texture and apertural disposition. At the same time we believe it is unrelated to A. aspensis and A. pentacamerata for similar reasons.
The wall texture (dutertrei-type cancellate) and apertural disposition of lozanoi are reminiscent of the Paleocene (essentially early Paleocene) genus Praemurica (see treatment of that genus in Olsson and others, 1999), although the relatively high spire in some individuals is not characteristic of the genus. At the same time we are unable to propose a suitable praemuricate ancestor for the lozanoi -prolata group in the early Eocene. Owing to the uncertainty surrounding the affinities and ancestry of lozanoi we assign it here provisionally to Praemurica (the obvious uncharacteristic high spire and the distinct stratigraphic gap from Zone P3 to E5/6 notwithstanding) and provide a separate entry for it here. Praemurica? lozanoi did not give rise to Guembelitroides nuttalli as suggested by Blow (1979, p. 855). [Berggren et al. 2006]

Most likely ancestor: Alicantina prolata - at confidence level 4 (out of 5). Data source: Soldan et al. 2018, fig 7.

Biostratigraphic distribution

Geological Range:
Notes: P. lozanoi s.s.: Zone E6 – E10; P. lozanoi s.l. (including prolata morphotype): E5-E9 (upper part). [Berggren et al. 2006]
Last occurrence (top): within E10 zone (41.89-43.23Ma, top in Lutetian stage). Data source: Berggren et al. 2006, fig 12.1
First occurrence (base): within E5 zone (50.67-52.54Ma, base in Ypresian stage). Data source: Berggren et al. 2006, fig 12.1

Plot of occurrence data:

Primary source for this page: Berggren et al. 2006 - Eocene Atlas, chap. 12, p. 397; Soldan et al. 2018

References:

Berggren, W. A., Olsson, R. K. & Premoli Silva, I. (2006a). Taxonomy, biostratigraphy and phylogenetic affinities of Eocene Astrorotalia, Igorina, Planorotalites, and Problematica (Praemurica? lozanoi). In, Pearson, P. N. , Olsson, R. K. , Hemleben, C. , Huber, B. T. & Berggren, W. A. (eds) Atlas of Eocene Planktonic Foraminifera. Cushman Foundation for Foraminiferal Research, Special Publication. 41(Chap 12): 377-400. gs :: ::

Bermudez, P. J. (1961). Contribucion al estudio de las Globigerinidea de la region Caribe-Antillana (Paleoceno-Reciente). Editorial Sucre, Caracas. 1119-1393. gs :: ::

Blow, W. H. (1979). The Cainozoic Globigerinida: A study of the morphology, taxonomy, evolutionary relationships and stratigraphical distribution of some Globigerinida (mainly Globigerinacea). E. J. Brill, Leiden. 2: 1-1413. gs :: ::

Bolli, H. M. (1957a). Planktonic foraminifera from the Eocene Navet and San Fernando formations of Trinidad. In, Loeblich, A. R. , Jr. , Tappan, H. , Beckmann, J. P. , Bolli, H. M. , Montanaro Gallitelli, E. & Troelsen, J. C. (eds) Studies in Foraminifera. U.S. National Museum Bulletin. 215: 155-172. gs :: ::

Colom, G. (1954). Estudio de las biozonas con foraminiferos del Terciario de Alicante. Boletin del Instituto Geologico y Minero de Espana. 66: 1-279. gs :: ::

Hillebrandt, A. , von (1976). Los foraminiferos planctonicos, nummulitidos y coccolitoforidos de la zona de Globorotalia palmerae del Cuisiense (Eoceno inferior) en el SE de Espana, (Provincias de Murcia y Alicante. Revista Española de Micropaleontología. 8(3): 323-394. gs :: ::

Nocchi, M., Amici, E. & Premoli Silva, I. (1991). Planktonic foraminiferal biostratigraphy and paleoenvironmental interpretation of Paleogene faunas from the subantarctic transect, Leg 114. Proceedings of the Ocean Drilling Program, Scientific Results. 114: 233-273. gs :: ::

Olsson, R. K., Hemleben, C., Berggren, W. A. & Huber, B. T. (1999). Atlas of Paleocene Planktonic Foraminifera. Smithsonian Institution Press, Washington, DC. 1-252. gs :: ::

Soldan, D., Petrizzo, M. R. & Premoli Silva, I. (2018). Alicantina, a new Eocene planktonic foraminiferal genus for the lozanoi group. Journal of Foraminiferal Research. 38(1): 41-52. gs :: ::

Stott, L. D. & Kennett, J. P. (1990). The Paleoceanographic and Paleoclimatic signature of the Cretaceous/Paleogene boundary in the Antarctic: Stable isotopic results from ODP Leg 113. Proceedings of the Ocean Drilling Program, Scientific Results. 113: 829-848. gs :: ::

Toumarkine, M. & Luterbacher, H. (1985). Paleocene and Eocene planktic foraminifera. In, Bolli, H. M. , Saunders, J. B. & Perch-Neilsen, K. (eds) Plankton Stratigraphy. Cambridge Univ. Press, Cambridge 87-154. gs :: ::

Toumarkine, M. (1983). Les Foraminifères planctoniques de l’Eocène moyen et supérieur des régions tropicales à temperées chaudes. In, p1-219 (ed.) . PhD thesis, Université Pierre et Marie Curie, Paris 6 1-219. gs :: ::

Warraich, M. Y. & Ogasawara, K. (2001). Tethyan Paleocene-Eocene planktic foraminifera from the Rakhi Nala and Zinda Pir land sections of the Sulaiman Range, Pakistan. Science Reports of the Institute of Geosciences, University of Tsukuba, Section B = Geological Sciences. 22: 1-59. gs :: ::


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Alicantina lozanoi compiled by the pforams@mikrotax project team viewed: 2-6-2020

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