Palaeontologia Electronica palaeo-electronica.org Angiosperm pollen grains from the Cuayuca Formation (Late Eocene to Early Oligocene), Puebla, Mexico Elia Ramírez-Arriaga, Mercedes B. Prámparo, and Enrique Martínez-Hernández ABSTRACT Systematic descriptions and illustrations of the best preserved angiosperm pollen grains (Monocotyledonae or Liliopsida: n= 7 and Dicotyledonae or Magnoliopsida: n= 41) recovered from Cuayuca Formation (late Eocene-early Oligocene), Puebla State, Mexico are provided, some of them of chronostratigraphic importance (Aglaoreidia pristina, Armeria, Bombacacidites, Corsinipollenites, Eucommia, Favitricolporites, Intratriporopollenites, Lymingtonia, Magnaperiporites, Malvacipollis spinulosa, Margo- colporites aff. vanwijhei, Momipites coryloides, Momipites tenuipolus, Mutisiapollis, Ranunculacidites operculatus, and Thomsonipollis sabinetownensis). Taxa identified from the Cuayuca Formation suggest local semiarid vegetation such as tropical decid- uous forest, chaparral, grassland, and arid tropical scrub, in which angiosperms are one of the main representatives. Nevertheless, temperate taxa from Pinus forest and cloud forest were also registered from regional vegetation. It is noticeable that at the present time, such taxa are well represented in the vegetation of the Balsas River Basin, which would suggest the existence of this type of flora in the Cuayuca region since the Oligocene. Elia Ramírez-Arriaga. Departamento de Paleontología, Instituto de Geología, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, C.P. 04510, México, Distrito Federal, [email protected]. Mercedes B. Prámparo. Centro Regional de Investigaciones Científicas y Tecnológicas, Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales, Unidad de Paleopalinología, Mendoza, Argentina. [email protected] Enrique Martínez-Hernández. Departamento de Paleontología, Instituto de Geología, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, C.P. 04510, México, Distrito Federal. [email protected] Keywords: systematic palynology; angiosperm pollen grains; Cuayuca Formation; Paleogene vegetation; Mexican Cenozoic basins PE Article Number: 18.1.2A Copyright: Paleontological Society January 2015 Submission: 27 February 2014. Acceptance: 19 December 2014 Ramírez-Arriaga, Elia, Prámparo, Mercedes B., and Martínez-Hernández, Enrique. 2014. Angiosperm pollen grains from the Cuayuca Formation (Late Eocene to Early Oligocene), Puebla, Mexico. Palaeontologia Electronica 18.1.2A: 1-38. palaeo-electronica.org/content/2015/1027-angiosperm-pollen-cuayuca-fm RAMÍREZ-ARRIAGA, PRÁMPARO, & MARTÍNEZ-HERNÁNDEZ: ANGIOSPERM POLLEN CUAYUCA FM. FIGURE 1. Location of the nine sections studied from the Cuayuca Formation, Puebla, Mexico. 1, Principal, “A” and “B” sections; 2, “F”, “H” and second sections; and 3, Lagunillas, Lagunillas de Rayón and Tzompahuacan sections. INTRODUCTION gene and Neogene pollen grains are lacking in most of those studies. The Cuayuca Formation was described by The present contribution deals with the taxon- Fries (1966), who designated a Miocene-Pliocene omy and systematics of selected angiosperm pol- age. Subsequently, palynostratigraphic research len grains (Monocotyledonae or Liliopsida and has allowed it to be re-assigned to a late Eocene- Dicotyledonae or Magnoliopsida) obtained from the early Oligocene age based on the presence of Cuayuca Formation, some of them of chronostrati- some index taxa, such as Cicatricosisporites doro- graphic importance. The Monocotyledonae (Liliop- gensis, Aglaoreidia pristina, Ephedripites claricri- sida) pollen grains are represented by status, Malvacipollis spinulosa, Margocolporites monosulcate and monoporate aperture types and aff. vanwijhei, Momipites tenuipolus, Ranuncula- Dicotyledonae (Magnoliopsida) pollen grains cidites operculatus, Polyadopollenites aff. pflugii, include colpate, colporoidate, colporate, porate, and Thomsonipollis sabinetownensis (Ramírez- and inaperturate pollen types. This contribution Arriaga et al., 2006, 2008). The Cuayuca Forma- constitutes one of the first taxonomic descriptions tion is within the Balsas Group; it was deposited in of angiosperm pollen grains recovered from the central Mexican Tertiary basins generated through evaporites of the Cuayuca Formation, which pro- tectonic events (Silva-Romo et al., 2000). Cur- vides useful information for a better understanding rently, those Paleogene basins are distributed of the paleobiodiversity and distribution of the Mex- throughout the Mezcala-Balsas hydrological sys- ican plant communities during the late Paleogene. tem (Fries, 1960) also known as the Balsas River Basin. The Cuayuca Formation yielded a diverse MATERIAL AND METHODS and well preserved terrestrial palynological assem- blage obtained from nine outcrop sections in A total of 49 samples were collected from nine Puebla State, southern Mexico (Figure 1). The pal- outcrop sections, with 21 samples bearing palyno- ynoflora studied includes gymnosperm and angio- morphs (Figure 2). All samples were processed sperm pollen grains, as well as pteridophyte and through standard methods (HCI and HF). The bryophyte spores. Ramírez-Arriaga et al. (2005) slides obtained have been stored in the UNAM published systematic descriptions of spores and (Universidad Nacional Autónoma de México), at gymnosperm pollen grains. the Geology Institute Palynological Collection There are several publications dealing with (IGLUNAM). Samples were examined with a Zeiss Mexican Cenozoic palynology (Graham, 1976; transmitted light microscope, and the photomicro- Martínez-Hernández et al., 1980; Tomasini-Ortíz graphs were taken with a Sony digital camera. In and Martínez-Hernández, 1984; Palacios and Rze- order to highlight the morphology, some photo- dowsky, 1993; Martínez-Hernández and Ramírez- graphs were taken in phase-contrast. Coordinates Arriaga, 1996, 1999; Graham, 1999), but taxo- of the illustrated specimens were provided, most of nomic studies with detailed descriptions of Paleo- them using an England Finder (EF) slide. Total 2 PALAEO-ELECTRONICA.ORG FIGURE 2. Stratigraphic columns with the location of the palynological samples studied from the Cuayuca Forma- tion, Puebla, Mexico. counts of taxa at the different sections studied are sections: 1) principal section; 2) section “A” (Cuay shown in Table. A); 3) section “B” (Cuay B); 4) section “F” (IzF); 5) section “H” (IzH); 6) second section (IzS); 7) Lagu- Statistical Analysis nillas section (Lag); 8) Lagunillas de Rayón section In order to determine vegetation types, taxa (LagRay); and 9) Tzompahuacan section (Tzo). were classified by means of multivariate analysis The WINCLADA data matrix from PAE analy- via hierarchical clustering analysis, in which groups sis (Nixon, 2002) shows rows that correspond to were defined using the Ward method with a Euclid- outcrop sections and columns for palynomorphs, ian distance of 1.8; this was done using program R whose presence (1) or absence (0) in each section (Johnson, 2000). In addition, Constrained Cluster is indicated. In hierarchic grouping, sections were Analysis (CONISS) through the incremental sum of clustered according to the presence of taxa. NONA squares method was applied using the Tilia Graph was used to carry out the parsimony analysis program, in order to define paleopalynological (Goloboff, 1993). The PAE analysis included a heu- changes in the Cuayuca Formation Mcy Member ristic search with tree bisection and reconnection (Grimm, 1987). This analysis was also able to give (TBR), branch swapping with 500 replications hold- information concerning the most representative ing 10 trees per replication, and further expanding elements in each paleocommunity. the memory to hold up to 10,000 trees. WINCLADA calculated three statistics that reflect the degree of The Parsimony Analysis of Endemicity (PAE) conflict among data: a) Length=L; b) Consistency Parsimony Analysis of Endemicity (Rosen, Index=CI; and c) Retention Index=RI. In the pres- 1988; Morrone and Crisci, 1995; Ramírez-Arriaga ent work, clades are supported by the presence of et al., 2008, 2014) was used to compare the paly- palynomorphs, and unique occurrences are nomorph diversity of Cuayuca Formation outcrop emphasized with black circles. 3 RAMÍREZ-ARRIAGA, PRÁMPARO, & MARTÍNEZ-HERNÁNDEZ: ANGIOSPERM POLLEN CUAYUCA FM. TABLE. List of angiosperm and gymnosperm pollen grains identified in Cuayuca Mcy Member: second section (Sec- ond); Tzompahuacan section (Tz); Lagunillas de Rayón section (LR); Lagunillas section (L); “B”section (“B”); “F” sec- tion (“F”); “H” section (“H”); Principal section (Principal); “A” section (“A”). SECTIONS Second Tz LR L "B" "F" "H" Principal "A" Samples Pb-8899 Pb-8902 Pb-9141 Pb-9515 Pb-9147 Pb-9343 Pb-8868 Pb-8869 Pb-8870 Pb-8871 Pb-8872 Pb-8890 Pb-8891 Pb-8896 Pb-8897 Pb-8898 Pb-9136 Pb-9137 Pb-9138 Pb-9334 Pb-9337 Pb-9339 Pb-9340 DYCOTYLEDONAE Alnus vera 111 133 2 1 1 Armeria type sp. 2 1 2 1 2 1 Bombacacidites sp. 11 Caryophyllaceae type 1 Caryapollenites sp. 2 1 1 1 1 Casuarinidites sp. 11 213 141 Chenopodipollis sp. 12312 63129265 Clavainaperturites sp. 1 1 Corsinipollenites spp. 4 1 2 4 2 Cupuliferoidaepollenites sp. 3 Cupuliferoipollenites sp. 1 Eucommia pollen type 31 1102 Euphorbiaceae type 21 Fabaceae pollen type 4 1 1 2 Favitricolporites sp. 1 Ficus type 1 Gesneriaceae type 1 Glycydendron pollen type 1 Intratriporopollenites sp. 1 1 Juglanspollenites sp. 1 1 Labiatae type 1 Landolphia pollen type