M2 - San Ramon section (Cretaceous of Argentina)

Where: Chubut, Argentina (42.7° S, 69.8° W: paleocoordinates 44.8° S, 58.3° W)

• coordinate estimated from map

When: Lefipán Formation, Maastrichtian (72.1 - 66.0 Ma)

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified mudstone

• The uppermost Maastrichtian is represented by tidal channel and tidal flat deposits with a low diversity Corbicula assemblage indicative of low salinity, high-stress environments unfavorable to most marine species that characterize the stable, normal marine, Maastrichtian infaunal guilds in most of the succession.
• This bed: Bioturbation - Heterolithic bedding.

•The Lefipán Formation consists of marine to marginal marine, fossiliferous sandstones and mudstones with some intercalated coquinas and conglomerates.

Size class: microfossils

• Samples were marine (dinoflagellate cysts)and continental (spores, pollen grains, fungal remains, fresh water algae) palynomorphs.

Preservation: original sporopollenin

Collection methods: chemical,

• Slides are housed in the palynological collection of the Museo Paleontológico Egidio Feruglio, Trelew, Chubut, Argentina (MPEF-Palin)numbers 100 to 113.

Primary reference: V. D. Barreda, N. R. Cúneo, P. Wilf, E. D. Currano, R. A. Scasso and H. Brinkhuis. 2012. Cretaceous/Paleogene Floral Turnover in Patagonia: Drop in Diversity, Low Extinction, and a Classopollis Spike. PLoS ONE 7(12):e52455 [C. Jaramillo/J. Moreno]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 151446: authorized by Carlos Jaramillo, entered by Jessica Moreno on 02.10.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

• Pollen terminology follows Punt et al. 2007.
Equisetopsida
 Pinidae - Pinidae
Classopollis sp. Pflug 1953
Lycopodiopsida
 Isoetales - Isoetaceae
Echinosporis sp. Krutzsch 1967 clubmoss
 Lycopodiales -
Retitriletes austroclavatidites Döring et al. 1963 clubmoss
 Lycopodiales - Lycopodiaceae
Sestrosporites pseudoalveolatus Dettmann 1963 clubmoss
 Selaginellales -
Camarozonosporites spp. Potonié 1956 clubmoss
Densoisporites velatus Dettmann 1963 clubmoss
Ceratosporites equalis Cookson and Dettmann 1958 clubmoss
Lycopsida
  -
Pteridopsida
  -
Leiotriletes sp. Potonie and Kremp 1954
Deltoidospora sp. Miner 1935
Cyathidites patagonicus Archangelsky 1972
Cyathidites minor Couper 1953
Cyathidites australis Couper 1953
Polypodiopsida
  - Gleicheniaceae
Gleicheniidites sp. Dettmann 1963
Clavifera triplex Bolkhovitina 1966
 Schizaeales - Polypodiidae
Convolutispora "sp. 2" Hoffmeister et al. 1955
  - Dicksoniaceae
Trilites "sp. 1" Erdtman and Couper 1947
Trilites volkheimerii Filatoff 1975
  - Polypodiaceae
Laevigatosporites ovatus Wilson and Webster 1946
  - Blechnaceae
Peromonolites vellosus Partridge 1973
Microfoveolatosporis
  -
Cycadopites
  -
Cycadopites sp. Wodehouse 1933
Ginkgoopsida
 Caytoniales -
Angiospermae
 Fagales -
Nothofagidites saraensis Menendez and Caccavari 1975
 Gunnerales -
 Proteales - Proteaceae
Propylipollis sp. Martin and Harris 1975
Propylipollis ambiguus Dettmann and Jarzen 1996
Proteacidites "sp. B" Cookson and Couper 1953
Lewalanipollis senectus Dettmann and Jarzen 1996
 Proteales -
Peninsulapollis "sp. 2" Dettmann and Jarzen 1988
Peninsulapollis gillii Dettmann and Jarzen 1988
Peninsulapollis cf. truswelliae Dettmann and Jarzen 1988
 Mesangiosperms - Arecaceae
Spinizonocolpites hialinus Archangelsky and Zamaloa 1986 palm
Arecipites sp. Nichols et al. 1973 palm
Arecipites minutiscabratus Mc Intyre 1968 palm
Longapertites aff. vaneendenburgi Geermerad et al. 1968 palm
 Mesangiosperms - Liliaceae
Liliacidites vermireticulatus Archangelsky and Zamaloa 1986
Liliacidites regularis Archangelsky 1973
 Poales - Typhaceae
 Chloranthales - Chloranthaceae
 Coniferales - Podocarpaceae
Lygistepollenites florinii Stover and Evans 1973 podocarp
Microcachryidites antarcticus Couper 1953 podocarp
Phyllocladidites mawsonii Cookson 1947 podocarp
Trisaccites microsaccatum Couper 1953 podocarp
Gamerroites psilasaccus Archangelsky 1988 podocarp
Podocarpidites sp. Cookson 1947 podocarp
Podocarpidites elegans Romero 1977 podocarp
Podocarpidites rugulosus Romero 1977 podocarp
Podocarpidites ellipticus Cookson 1947 podocarp
Magnoliopsida
  -
Retitricolporites "sp. 1" Van der Hammen and Wymstra 1964
Bryopsida
  -
Stereisporites sp. Pflug 1953
Stereisporites (Tripunctisporis) sp.