Carnets de Géologie [Notebooks on Geology]: Article 2013/07 (CG2013_A07)

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Contents


[1) Introduction] [2) Material and method] [3) "Acroporella occidentalis"]
[4) Cymopolia mayaense Johnson & Kaska, 1965] [5) Cylindroporella elassonos Johnson & Kaska, 1965]
[6) Conclusions] [Bibliographic references] and ... [Plates]


Revision of the Jesse Harlan Johnson Collection.
Part 1. Some fossil Dasycladales from Guatemala

Bruno Granier

Department of Ecology and Evolutionary Biology, The University of Kansas, 1200 Sunnyside Avenue, Lawrence, Kansas 66045 (USA)

Rajka Radoičić

Kralja Petra I, 38, 11000, Beograd (Serbia)

Katica Drobne

Ivan Rakovec Paleontological Institute, ZRC SAZU, Novi trg 2, 1000 Ljubljana (Slovenia)

Manuscript online since November 11, 2013
[Scientific editor: Michel Moullade; technical editor: Bruno Granier; language editor: Stephen Eagar]

Click here to download the PDF version!

Abstract

This first report is a revision of fossil calcareous green algae (Dasycladales) described from the Upper Cretaceous and Paleocene series of Guatemala. Among other things in their 1965 paper J.H. Johnson and H.V. Kaska introduced three new species originally referred to the genera Acroporella, Cylindroporella, and Cymopolia. One species, which has previously been referred to the genus Cylindroporella, is a foraminifer.

Key-words

Paleocene; Upper Cretaceous; Guatemala; Dasycladales.

Citation

Granier B., Radoičić R. & Drobne K. (2013).- Revision of the Jesse Harlan Johnson Collection. Part 1. Some fossil Dasycladales from Guatemala.- Carnets de Géologie [Notebooks on Geology], Brest, Article 2013/07 (CG2013_A07), p. 281-301.

Résumé

Révision de la Collection Jesse Harlan Johnson. Première partie. Quelques Dasycladales fossiles du Guatémala.- Ce premier rapporte traite de la révision de quelques algues calcaires vertes fossiles (Dasycladales), ou supposées telles (dans les faits un de ces taxons attribué au genre Cylindroporella est un foraminifère), décrites de terrains crétacés et paléocènes du Guatémala. Dans leur papier de 1965 J.H. Johnson and H.V. Kaska avaient entre autres choses introduit trois nouvelles espèces attribuée à l'origine aux genres Acroporella, Cylindroporella et Cymopolia.

Mots-clefs

Paléocène ; Crétacé supérieur ; Guatémala ; Dasycladales.


1) Introduction

Jesse Harlan Johnson (1892-1974) was a prolific American paleophycologist (Wray, 1977, 1985; anonymous, last consulted 2013-09-24) who described a number of fossil algal taxa, both red and green "calcareous algae", including mostly new species, but less commonly new genera. Several years after his death part of his collection, which was then located at the Colorado School of Mines in Golden, was transferred to the University of Kansas at Lawrence. Another significant part of his collection, i.e., the specimens bearing U.S. National Museum labels in his publications, is stored at the Smithsonian Institution in Washington D.C.. One cannot exclude the possibility that further specimens might be in some geological survey, but the core of the collection (the potential "types") was sent to the Smithsonian awaiting paleophycologists to check this reference material. During the course of a short-term visit the first author (B.G.) was given the opportunity to access this collection and to study part of this material. The following report is the first of a forthcoming series dedicated to Jesse Harlan Johnson's fossil calcareous algae. It deals with three "species" described in Johnson and Kaska (1965): "Acroporella occidentalis", a nomen nudum (see discussion in Deloffre & Granier, 1992, and herein), Cymopolia mayaense Johnson & Kaska, 1965, and Cylindroporella elassonos Johnson & Kaska, 1965.

2) Material and method (Fig. 1 )

With respect to these taxa, Johnson and Kaska (1965) list four thin sections with an USNM registration number (No. 42499, 42500, 42504, and 42524, ink writing, which correspond respectively to locality numbers 4819, 4819(2), 7747, and 10029, glass engraving). However the thin section 42500 is probably lost as there is no record for it in the Smithsonian Institution's inventory. The quality of the remaining thin sections varies significantly: the color of the Canada balsam has locally turned from light yellow to dark brown; the rock slices themselves have different thicknesses; the sections of the fossil specimens are random; etc.

The microfacies of slide 42499 is bioturbated bioclastic wackestone with benthic foraminifers and calcareous green algae. Slide 42524 is also a bioturbated foraminiferal wackestone, but it has suffered some diagenetic alteration. The last slide, i.e., No. 42504, consists of a chloralgal grainstone with the typical circumgranular fibrous cementation that characterizes submarine hardground formation (the remaining intergranular pore space is occluded by a late phreatic drusy cement).


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Figure 1: The three (remaining) thin sections studied.

3) "Acroporella occidentalis" (Fig. 2 ) [BG & RR]

According to Deloffre & Granier (1992), this taxon is a nomen nudum because its type was not properly identified. Actually, Johnson & Kaska (1965, p. 78) clearly state that the type slide is "4819 = U.S.N.M. No. 42499" and illustrate two sections of the algal thallus ("Plate 7, figures 1, 2"; herein Fig. 2 ). In the figure caption of their Plate 7, none of the sections is explicitly defined as the type-specimen (holotype or type) or even referred to the type slice.

We found that none of these figured algal sections occurs in the type slice. Accordingly, none can be considered as a potential candidate to be selected as the lectotype. None of them are visible on the second thin section, even though Johnson & Kaska (1965, p. 78) state that slide "7747 = U.S.N.M. No. 42504" was also figured. In conclusion, both illustrated sections probably come from a third slide, labelled "4819(2) = U.S.N.M. No. 42500". Because this last slice is lost, this material (corresponding to the printed photomicrographs), which otherwise could have been considered as syntypes, cannot be used to define a lectotype. At this stage there are two options remaining:

1) we select a neotype from the type slice and therefore we keep the original specific epiteth, i.e., "occidentalis";

2) alternatively we could select an holotype (and paratypes) and give a brand new name to these specimens. In the same paper, Johnson & Kaska (1965) have already introduced three new species all bearing "occidentalis" as a specific epithet (one Jania, one Larvaria and the "Acroporella").

We retained the first option in order to avoid further confusion. This option implies that both the date of valid publication (2013 in lieu of 1965) and the authorship of the species change. Following Radoičić (1990) we shall not refer the species to the Triploporellacean genus Acroporella Praturlon, 1964, but to the Polyphysacean genus Clypeina (Michelin, 1845), that already includes more than 40 species (see Deloffre & Granier, 1992; Granier & Deloffre, 1993, 1994; and Granier, 2013, for a recent addition to the list).


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Figure 2: Duplicate of  "Plate 7, figures 1, 2" in Johnson & Kaska (1965) with "Acroporella occidentalis". Some rights reserved.

Phylum Chlorophyta

Class Dasycladophyceae Hoek et al., 1995

Order Dasycladales Pascher, 1931

Family Polyphysaceae (Kützing, 1841)

Tribe Clypeineae (Elliott, 1968)

Genus Clypeina (Michelin, 1845)

Clypeina occidentalis Granier & Radoičić in Granier et al., 2013

[= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965]

(Fig. 2 ; Pl. 1 , figs. a-f; Pl. 2 , figs. a-l; Pl. 3 , figs. a-j; Pl. 4 , figs. a-c; Pl. 8 , fig. d)

Neotype (selected herein): Pl. 2 , fig. b. This specimen is an oblique section with three successive verticils. Thin section USNM 42499 (=4819, see Fig. 1 ).

Paratypes: all the accompanying sections from the same material (Pl. 1 , figs. a-f; Pl. 2 , figs. a-l; Pl. 3 , fig. a)

Measurements: The new measurements for the external diameter of the calcareous coating (D), the internal diameter (d) and their relative ratio (d/D) are displayed in the table below. Blue (cyan) cells for data measured on slide 42499, green (lime) cells for slide 42504, yellow cells for the combination of both slides.

Clypeina occidentalis D µm d µm d/D %
42499 (=4819) 438 171 39%
42499 (=4819) 400 210 52%
42499 (=4819) 476 210 44%
42499 (=4819) 571 286 50%
42499 (=4819) 495 200 40%
42499 (=4819) 571 190 33%
42499 (=4819) 476 171 36%
42499 (=4819) 429 190 44%
42499 (=4819) 524 162 31%
42504 (=7747) 381 190 50%
42504 (=7747) 571 324 57%
average ALL (11 measur.) 485 210 43%
standard deviation (σ) 66 50 8%
average 42499 (9 measur.) 487 199 41%
standard deviation (σ) 66 50 7%

In the type slide, D = ca. 490 +/- ca. 65µm and d = ca. 200 +/- ca. 50µm for a ratio d/D = 41 +/- 7%. The maximum length is 2.0mm (Pl. 1 , fig. a) and the spacing of the whorls (including the height of a whorl) is quite variable, ranging from 190 to 380µm. The "pores" (laterals) gradually increase in diameter from 50µm in the proximal part to 80µm in the distal part. There are usually 12 laterals per verticil (but this number may vary from ten to twenty). These laterals arise at steep angle (ca. 30°) along the main axis. Because they are commonly abraded distally, they are in average 170µm in length but, in better preserved specimens (Pl. 1 , fig. f; Pl. 2 , fig. b), they may reach 350µm.

Discussion: The general morphological features, the measurements, and last, but not least, both their stratigraphic ranges [1] and their geographic locations [2] point to synonymize this species (now validly published) with Clypeina elliotti J.-P. & R. Beckmann, 1966 (op. cit., Pl. 11, figs. 155-159). When writing their manuscript the latter authors were unaware of the existence of a "competitor". Later, in a postscript note (Beckmann J.-P. & R., 1966, p. 41), they acknowledge the contribution newly published by Johnson & Kaska (September 1965). We understand that, on the basis of the poor illustration of "Acroporella occidentalis" (Johnson & Kaska, 1965, Pl. 7, figs. 1-2; herein Fig. 2 ), they could not considered a possible synonymy with their new species.

[1] "Lower Eocene" for Clypeina occidentalis versus "Paleocene (or lower Eocene ? )" for Clypeina elliotti.

[2] Guatemala for Clypeina occidentalis versus Cuba for Clypeina elliotti.

4) Cymopolia mayaense Johnson & Kaska, 1965 (Fig. 3.1-4 ) [BG]

According to Johnson & Kaska (1965, p. 85), the type slide is "4819 = U.S.N.M. No. 42499" but none of their illustrated specimens (op. cit., Pl. 18, figs. 1-4; herein Fig. 3.1-4 ) occurs precisely in this thin section. They say they "also figured slide" (..) "4819(2) = U.S.N.M. No. 42500" but one should not forget that this last slice is lost. Fortunately, we identified one photomicrograph (Johnson & Kaska, 1965, Pl. 18, fig. 3) as originating from a capture of slide "7747 = U.S.N.M. No. 42504". It includes several sections, which can be treated as syntypes, and one of them will be selected as the lectotype.


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Figure 3: Duplicate of  "Plate 18" in Johnson & Kaska (1965) with Cymopolia mayaense and "Cylindroporella elassonos". Some rights reserved.

Phylum Chlorophyta

Class Dasycladophyceae Hoek et al., 1995

Order Dasycladales Pascher, 1931

Family Dasycladaceae Kützing, 1843

Tribe Dasycladeae Pia, 1920

Sub-Tribe Cymopoliinae (Pia, 1931)

Genus Cymopolia J.V. Lamouroux, 1816

Cymopolia mayaense Johnson & Kaska, 1965

(Fig. 3.1-4 ; Pl. 4 , figs. d-f; Pl. 5 , figs. a-i; Pl. 6 , figs. a-c; Pl. 7 , figs. a-f; Pl. 8 , fig. e)

Synonymy list:

1965 Cymopolia mayaense n.sp.- Johnson & Kaska, p. 83-85, Pl. 18, figs. 1-4
("type": Pl. 18, fig. 1; herein  Fig. 3.1 );

1966 Cymopolia cf. kurdistanensis Elliott.- J.-P. & R. Beckmann, p. 38, Pl. 11, figs. 165-167;

non 1968 Cymopolia mayaense.- Segonzac, p. 385, Pl. (3) [Pl. h.-t. XVIII], fig. 5;

non 1978 Cymopolia mayaense.- Deloffre & Radoičić, p. 71-72, Pl. 7, figs. 3-4;

1982 Cymopolia mayaense.- Deloffre & Génot, p. 68-69, Pl. 5, fig. 3 (= Pl. 18, fig. 1 in Johnson & Kaska, 1965);

1992 Cymopolia mayaense.- Deloffre & Granier, p. 344 (not illustrated);

1998 Cymopolia mayaense.- Barattolo, p. 76-77, Pl. 11, figs. 1-6; Pl. 12, figs. 1-2; Pl. 13, fig. 1

Lectotype (selected herein): Pl. 6 , fig. b pars. This is the tangential section at the bottom of the figure, which shows (?) 12 successive verticils, already illustrated by Johnson & Kaska (1965, Pl. 18, fig. 3 pars; herein Fig. 3.3 pars). Thin section USNM 42504 (=7747, see Fig. 1 ).

Paratypes: Pl. 6 , fig. b pars, the accompanying random sections from the same photomicrograph, already illustrated by Johnson & Kaska (1965, Pl. 18, fig. 3 pars; herein Fig. 3.3 pars). Thin section USNM 42504 (=7747).

Measurements: The new measurements for D, d and d/D are given in the table below. Blue (cyan) cells for data measured on slide 42499, green (lime) cells for slide 42504, yellow cells for the combination of both slides.

Cymopolia mayaense D µm d µm d/D (%)
42499 (=4819) 381 171 45%
42499 (=4819) 876 371 42%
42499 (=4819) 676 305 45%
42504 (=7747) 705 295 42%
42504 (=7747) 381 124 33%
42504 (=7747) 714 248 35%
42504 (=7747) 724 248 34%
42504 (=7747) 619 286 46%
42504 (=7747) 762 381 50%
42504 (=7747) 905 381 42%
42504 (=7747) 457 171 38%
average ALL (11 measur.) 655 271 41%
standard deviation (σ) 180 89 6%
average 42504 (8 measur.) 658 267 40%
standard deviation (σ) 169 91 6%

In the slide 42504, D = ca. 660 +/- ca. 170µm and d = ca. 270 +/- ca. 90µm for a ratio d/D = 40 +/- 6%. The maximum length is 2.4mm (Pl. 5 , fig. b) and the interwhorl spacing (including the height of a whorl) ranges from 120 to 170µm. There are some 20 laterals per verticil. The sterile primary or secondary orders of the laterals rarely exceed 40µm in diameter. The subspherical fertile ampulla (they are ovoidal to ellipsoidal in Cymopolia heraki Gušić, 1967: see Pl. II, fig. 10 op. cit., for instance) in terminal position on a primary and surrounded by 4 to 6 secondaries reaches 100µm in diameter.

Discussion: With an outer diameter D = ca. 660 +/- ca. 170µm and an inner diameter d = ca. 270 +/- ca. 90µm (in the slide 42504), this species is by far the smallest of all the Cenozoic representatives of the genus Cymopolia. Being the smallest, it also has proportionally a lesser number of laterals per verticil than the larger Cymopolia elongata (Defrance, 1825), for instance (see Deloffre & Génot, 1982). Again, material described from Cuba by J.-P. & R. Beckmann (1966, Pl. 11, figs. 165-167) as "Cymopolia cf. kurdistanensis Elliott" is very similar, if not identical, to the material from Guatemala.

5) Cylindroporella elassonos Johnson & Kaska, 1965 (Fig. 3.1-4 ) [BG & RR]

Johnson & Kaska (1965) illustrated under their "Plate 18, figure 5" (Fig. 3.5 ) the "Type" of their "Cylindroporella elassonos n.sp.". They give a perplexing and puzzling "Description" (op. cit., p. 82) and also refer to a type "Slide 10029 = U.S.N.M. No. 42524" (Fig. 1 ). There are no bioclasts referable to algae in this slide. We examined it and were able to capture a new image (Pl. 8 , fig. a). The so-called "Cylindroporella" is a foraminifer, probably a Dicyclina sp. (or a Cuneolina sp.), but not an alga. The thin section includes more specimens (Pl. 8 , figs. b-c) of these agglutinated foraminifers, which are rather common in Upper Cretaceous shallow-water carbonate facies.

6) Conclusions

Among the three taxa introduced by Johnson & Kaska (1965), 1) only one species, i.e., Cymopolia mayaense, passed the re-evaluation. We selected a lectotype out of the syntypes to replace its original holotype, which is lost. 2) Another species, i.e., "Acroporella occidentalis", was not validly published by lack of a correct definition of its holotype. We selected a neotype for the combination Clypeina occidentalis, but because the year of reference is 2013 (not 1965) it now proves to be a junior synonym of Clypeina elliotti J.-P. & R. Beckmann, 1966. 3) The last one, i.e., "Cylindroporella elassonos", is actually not an alga but a foraminifer.

The stratigraphic range of the Cenozoic species, i.e., Clypeina occidentalis and Cymopolia mayaense, is restricted to the Paleocene on the basis of the foraminiferal assemblage that includes: 1) Pseudorhapydionina moulladei Pécheux, 1995 (quoted as "Rhapydionina" by Johnson & Kaska, 1965), in both thin sections [Pl. 2 , fig. f; Pl. 4 , figs. d & f; Pl. 5 , fig. f; Pl. 8 , figs. g & j]; 2) "Quasiborelis" floridanus (Cole) [Pl. 4 , fig. f] and Kayseriella cf. decastroi Sirel [Pl. 8 , fig. i] in thin section 42504; 3) Idalina cf. sinjarica Grimsdale and Haymanella sp. in thin section 42499.

This first contribution to the revision of the Jesse Harlan Johnson Collection demonstrates the necessity to maintain palaeophycological reference collections, primarily as reference material, but also because of the increase in our knowledge, to re-examine these algal microfossils.

Acknowledgements

The first author (BG) benefited from a Smithsonian Fellowship allowing him to investigate the J. Harlan Johnson Collection stored in the premises of the Smithsonian Institution. This research was also partly sponsored by the Association "Carnets de Géologie". He would like to thank the staff of the Department of Paleobiology at the Smithsonian National Museum of Natural History and particularly William A. DiMichele and Jonathan G. Wingerath for their hospitality and having facilitated his work there, Una Farrell for having provided information on Johnson Collection at the Biodiversity Institute of the University of Kansas in Lawrence, as well as Vlasta Ćosović for early suggestions regarding the associated benthic foraminifers. Finally he also acknowledge the positive comments and suggestions of a friendly group of paleophycologists that includes Filippo Barattolo, Ioan I. Bucur, Marc André Conrad and Felix Schlagintweit.

Bibliographic references

anonymous (last consulted 2013-09-24).- J. Harlan Johnson Collection, Kansas Collection, RH MS 735, Kenneth Spencer Research Library, University of Kansas Libraries.- online: http://hdl.handle.net/10407/0546075094

Barattolo F. (1998).- Dasycladacean green algae and microproblematica of the uppermost Cretaceous-Paleocene in the Karst area (NE Italy and Slovenia). In: Hottinger L. & Drobne K. (eds.), Paleogene shallow benthos of the Tethys, 2.- Dela - Opera SAZU, Ljubljana, (Classis IV), p. 65-127 (16 Pls.).

Beckmann J.-P. & Beckmann R. (1966).- Calcareous algae from the Cretaceous and Tertiary of Cuba.- Mémoires suisses de Paléontologie, Basel, vol. 85, 47 p. (12 Pls.).

Deloffre R. & Génot P. (1982).- Les algues Dasycladales du Cénozoïque.- Bulletin du Centre de Recherche Exploration-Production elf-Aquitaine, Pau, Mémoire 4, 247 p.

Deloffre R. & Granier B. (1992).- Inventaire des Algues Dasycladales fossiles. I° partie- Les Algues Dasycladales du Tertiaire.- Revue de Paléobiologie, Genève, vol. 11, n° 2, p. 331-356.

Deloffre R. & Radoičić R. (1978).- Algues calcaires (Dasycladales) du Paléocène de Slovénie (Yougoslavie).- Bulletin du Centre de Recherche Exploration-Production elf-Aquitaine, Pau, vol. 2, n° 1, p. 39-60.

Granier B. (2013).- Heteroporella ? paucicalcarea (Conrad, 1970), an Urgonian Dasycladalean alga revisited.- Carnets de Géologie [Notebooks on Geology], Brest, Letter 2013/01  (CG2013_L01), p. 59-65. DOI: 10.4267/2042/48737

Granier B. & Deloffre R. (1993).- Inventaire des Algues Dasycladales fossiles. II° partie- Les Algues Dasycladales du Jurassique et du Crétacé.- Revue de Paléobiologie, Genève, vol. 12, n° 1, p. 19-65.

Granier B. & Deloffre R. (1994).- Inventaire des Algues Dasycladales fossiles. III° partie- Les Algues Dasycladales du Permien et du Trias.- Revue de Paléobiologie, Genève, vol. 14, n° 1, p. 49-84.

Gušić I. (1967).- New Dasycladaceae from the Maastrichtian of Bešpelj near Jajce (western Bosnia).- Geološki Vjesnik, Zagreb, Svezak 20 (1966), p. 117-126 (Pls. I-VI).

Johnson J.H. & Kaska H.V. (1965).- Fossil Algae from Guatemala.- Professional Contributions of the Colorado School of Mines, Golden, n° 1, 152 p. (47 Pls.).

Pécheux M.J.-F. (1995).- Pseudorhapydionina moulladei, nouveau macroforaminifère du Paléocène du Chiapas, SE Mexique.- Revue de Micropaléontologie, Paris, vol. 38, n° 2, p. 169-174-76.

Radoičić R. (1990).- Paleogene dasycladalean algae from the subsurface of the Western Iraqi Desert.- Bulletin de l'Académie Serbe des Sciences et des Arts, Beograd, (Sciences mathématiques et naturelles, Sciences naturelles), t. CII, nº 32, p. 91-103.

Radoičić R. (1991).- Acicularia tavnae sp. nov. and other Acetabulariaceae from the Palaeocene of eastern Majevica (NE Bosnia, Dinarides).- Geologija, Ljubljana, Knjiga 34 (vol. 34), p. 57-76.

Segonzac G. (1968).- Les Cymopolia (Dasycladacées) du Thanétien des Pyrénées.- Bulletin de la Société d'Histoire naturelle de Toulouse, t. 104, fasc. 3-4, p. 381-391 (Pls. XVI-XVIII).

Wray J.L. (1977).- Memorial to J. Harlan Johnson 1892-1974.- Memorials - Geological Society, Boulder, 6 p.

Wray J.L. (1985).- J. Harlan Johnson (1892-1974), father of American paleoalgology. In: Toomey D.F. & Nitecki M.H. (eds.), Paleoalgology; contemporary research and applications.- Springer-Verlag, Berlin, p. 3-8.


Plates


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Plate 1: Figures a-f: Clypeina occidentalis Granier & Radoičić in Granier et al., 2013 [= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965], thin section 42499. a) axial section; b) long oblique section; c) short oblique (above) and tangential (below) sections; d) axial section; e) deep tangential section (to compare with J.-P. & R. Beckmann, 1966: Pl. 11, figs. 155-156); f) tangential section (to compare with Radoičić, 1991: Pl. 4, fig. 2).


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Plate 2: Figures a-l: Clypeina occidentalis Granier & Radoičić in Granier et al., 2013 [= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965], thin section 42499. a) axial section; b) the neotype, an oblique section; c) tangential section; d) tangential section of two ( ?) laterals (above) and oblique section of a single whorl (below); e) oblique (above) and tangential (below) sections; f) oblique section (with Pseudorhapydionina moulladei Pécheux, 1995); g) subtransverse section; h) oblique section of a single whorl; i) oblique section; j) subtransverse section; k) subtransverse section; l) subtransverse section.


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Plate 3: Figures a-j: Clypeina occidentalis Granier & Radoičić in Granier et al., 2013 [= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965], thin sections 42499 (a) and 42504 (b-j). a) subaxial section; b) oblique section; c) oblique section; d) tangential section; e) oblique section; f) two oblique sections; g) tangential section; h) oblique section; i) subtransverse section; j) subtransverse section (this section is at the bottom of figure 3 of Plate 18 of Johnson & Kaska, 1965).


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Plate 4: Figures a-c: Clypeina occidentalis Granier & Radoičić in Granier et al., 2013 [= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965], thin section 42504. a) tangential section; b) tangential section; c) tangential (above) and oblique (below) sections.

Figures d-f: Cymopolia mayaense Johnson & Kaska, 1965, thin section 42504. d) oblique (subtransverse) section, with Pseudorhapydionina moulladei Pécheux, 1995; e) tangential section; f) oblique (subaxial) section, with Pseudorhapydionina moulladei Pécheux, 1995, and "Quasiborelis" floridanus (Cole).


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Plate 5: Figures a-i: Cymopolia mayaense Johnson & Kaska, 1965, thin sections 42499 (a-c, e & h-i) and 42504 (d & f-g). a) subaxial section; b) deep tangential section; c) oblique section; d) oblique section; e) oblique section; f) partial oblique section, with Pseudorhapydionina moulladei Pécheux, 1995; g) oblique section; h) tangential section; i) tangential section.


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Plate 6: Figures a-c: Cymopolia mayaense Johnson & Kaska, 1965, thin section 42504. a) random sections (the axial section to the right might not belong to Cymopolia); b) random sections, mostly oblique and one tangential. This last section at the bottom is herein selected as a lectotype (actually these specimens are those illustrated on figure 3 of Plate 18 of Johnson & Kaska, 1965); c) oblique section.


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Plate 7: Figures a-f: Cymopolia mayaense Johnson & Kaska, 1965, thin section 42504. a) oblique section; b) subaxial section; c) oblique section; d) axial section; e) oblique section; f) oblique section.  


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Plate 8: Figures a-c: thin section 42524. a) Cylindroporella elassonos Johnson & Kaska, 1965. The fossil pointed by the white arrows (actually the "Type" illustrated on figure 5 of Plate 18 of Johnson & Kaska, 1965) is a foraminifer, i.e., a representative either of the genus Dicyclina or of the genus Cuneolina; b) random section of a similar foraminifer; c) assemblage with Ostracoda and Foraminifera, including Dicyclina sp., Nezzazatinella picardi (Henson) and miliolids.

Figures d & f-i: thin section 42504. d) Clypeina occidentalis Granier & Radoičić in Granier et al., 2013 [= Clypeina occidentalis Johnson & Kaska ex Granier & Radoičić in Granier et al., 2013, non 1965], axial section; f) indetermined foraminifer (Valvulinid); g) Pseudorhapydionina moulladei Pécheux, 1995, transverse section; h) Jodotella sp., axial section; i) Kayseriella cf. decastroi Sirel; j) Pseudorhapydionina moulladei Pécheux, 1995, oblique section.

Figure e: thin section 42499. Cymopolia mayaense Johnson & Kaska, 1965, oblique section.