TY - JOUR
T1 - Fossil woods from the late Campanian-early Maastrichtian Olmos Formation, Coahuila, Mexico
AU - Estrada-Ruiz, Emilio
AU - Martínez-Cabrera, Hugo I.
AU - Cevallos-Ferriz, Sergio R.S.
N1 - Funding Information:
We would like to acknowledge PASAC (Paleontólogos Aficionados de Sabinas A.C.), M. Sc. René Hernández, M. Sc. José Luis Ramírez, Ing. Geól. Judith Callejas, Ing. Geól. José Juan González and Mr. Martín Galicia for their field assistance. Some wood samples were kindly provided by PASAC. Josefina Barajas-Morales and Patricia Olvera are thanked for allowing access to the slide collections at MEXU (Instituto de Biología, UNAM) and INIFAP. Comments by Dra. Laura Calvillo-Canadell and Dr. Francisco Vega-Vera enhanced our discussion. Dr. Fernando Chiang Cabrera oriented us in the correct use of scientific names. This work was improved with the comments of two anonymous reviewers. Comments by Mrs. Magdalena Alcayde, Editorial Department, Instituto de Geología, UNAM, improved a preliminary English version. This study is based in part on the PhD thesis of Emilio Estrada Ruiz at Posgrado en Ciencias de la Tierra, Instituto de Geología, UNAM. Funds by CONACyT (45065) and DGAPA-UNAM (IN208500 and IN201103) through grants to S.R.S.C.F., and a CONACyT (188612) and DGEP-UNAM student loans to E.E.R. are appreciated.
PY - 2007/6
Y1 - 2007/6
N2 - Three fossil wood types are described from the Olmos Formation, Coahuila, Mexico. The anatomical characters of two of them enable identification to Malvaceae and Fagaceae, while the affiliation of the third type is uncertain (Fagaceae?). The wood of the Malvaceae fossil plant is characterised by the presence of vessel-ray and vessel-parenchyma pits with reduced borders, larger than the intervascular pits, scanty paratracheal parenchyma, septate fibres and storied structure. This wood type, Javelinoxylon, has been also found in the Maastrichtian Javelina Formation, Texas. Aggregate and uniseriate homocellular rays, apotracheal diffuse and diffuse in aggregates parenchyma, simple perforation plates, vessel-ray pits variable with reduced borders and vasicentric tracheids relate the wood of a second plant to Quercinium. The third wood type, Sabinoxylon pasac Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz, is very similar to some species of Quercinium; however, the presence of heterocellular rays and the almost exclusive presence of scalariform perforation plates make unlikely its relationship with this genus. Since observation of vessel parenchyma and vessel ray pits was not possible, its inclusion in Fagaceae cannot be confirmed. Nevertheless, S. pasac and Quercinium centenoae Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz represent the earliest record of fagaceous plants in Mexico, while the presence of Javelinoxylon weberi Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz extends the geographic distribution of the genus in North America.
AB - Three fossil wood types are described from the Olmos Formation, Coahuila, Mexico. The anatomical characters of two of them enable identification to Malvaceae and Fagaceae, while the affiliation of the third type is uncertain (Fagaceae?). The wood of the Malvaceae fossil plant is characterised by the presence of vessel-ray and vessel-parenchyma pits with reduced borders, larger than the intervascular pits, scanty paratracheal parenchyma, septate fibres and storied structure. This wood type, Javelinoxylon, has been also found in the Maastrichtian Javelina Formation, Texas. Aggregate and uniseriate homocellular rays, apotracheal diffuse and diffuse in aggregates parenchyma, simple perforation plates, vessel-ray pits variable with reduced borders and vasicentric tracheids relate the wood of a second plant to Quercinium. The third wood type, Sabinoxylon pasac Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz, is very similar to some species of Quercinium; however, the presence of heterocellular rays and the almost exclusive presence of scalariform perforation plates make unlikely its relationship with this genus. Since observation of vessel parenchyma and vessel ray pits was not possible, its inclusion in Fagaceae cannot be confirmed. Nevertheless, S. pasac and Quercinium centenoae Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz represent the earliest record of fagaceous plants in Mexico, while the presence of Javelinoxylon weberi Estrada-Ruiz, Martínez-Cabrera et Cevallos-Ferriz extends the geographic distribution of the genus in North America.
KW - Coahuila
KW - Fagaceae
KW - Malvaceae
KW - Olmos Formation
KW - late Campanian-early Maastrichtian
UR - http://www.scopus.com/inward/record.url?scp=34247628917&partnerID=8YFLogxK
U2 - 10.1016/j.revpalbo.2006.09.003
DO - 10.1016/j.revpalbo.2006.09.003
M3 - Artículo
SN - 0034-6667
VL - 145
SP - 123
EP - 133
JO - Review of Palaeobotany and Palynology
JF - Review of Palaeobotany and Palynology
IS - 1-2
ER -