The Tuzancoa Formation: Evidence of an Early Permian Submarine Continental Arc in East-Central Mexico

The discovery of a new locality yielding giant Guadalupian (Lower Permian) fusulinids in east-central Alaska extends the range of these forms much farther north than previously known, and into a tectonostratigraphic terrane from which they previously had not been reported. The number of areas from which giant parafusulinids are known in North America is thus raised to eight. Three of these localities are in rocks that previously had been referred to the allochthonous McCloud belt arc, and one, West Texas, is known to have been part of Paleozoic North America. Comparison of species from all areas suggests that there are two closely related species groups: one represented in Texas and Coahuila, and the other represented in Sonora, northern California, northeastern Washington, southern and northern British Columbia, Alaska, and apparently in Texas. These groups may differ because they are of slightly different ages or because interchange between the faunas of Texas–Coahuila area and the other regions was somewhat inhibited during the Early Permian.

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Cordilleran deformation along the eastern edge of the Valles–San Luis Potosí carbonate platform, Sierra Madre Oriental fold-thrust belt, east-central Mexico

Geological Society of America Bulletin ◽

10.1130/0016-7606(1984)95<1387:cdatee>2.0.co;2 ◽

1984 ◽

Vol 95 (12) ◽

pp. 1387 ◽

Cited By ~ 32

Author(s):

MAX SUTER

Keyword(s):

Carbonate Platform ◽

Central Mexico ◽

Thrust Belt ◽

East Central ◽

Sierra Madre Oriental ◽

San Luis ◽

Sierra Madre ◽

San Luis Potosi ◽

Eastern Edge ◽

San Luis Potosí

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Early Permian Fusulinids from the Owens Valley Group, east-central California

10.1130/spe217 ◽

1988 ◽

Keyword(s):

Early Permian ◽

Owens Valley ◽

East Central ◽

Central California

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Resource Allocation Among Cladodes of Opuntia Robusta From East-central Mexico

10.21203/rs.3.rs-161086/v1 ◽

2021 ◽

Author(s):

Héctor Javier León-Solano ◽

Mariusz Krzysztof Janczur ◽

Emilio González-Camarena ◽

Marcin Czarnoleski ◽

Bartosz Jenner ◽

...

Keyword(s):

Resource Allocation ◽

Salicylic Acid ◽

Resource Availability ◽

Stress Factors ◽

Central Mexico ◽

Hydroxybenzoic Acid ◽

East Central ◽

Vegetative Tissues ◽

Resource Availability Hypothesis ◽

New Hypothesis

Abstract The Optimal Defense Hypothesis (ODH) predicts that younger, more valuable plant organs should be better defended. We tested this hypothesis in Opuntia robusta Wendl. since its sequential, hierarchical and segmented architecture permits the consideration of a possible reallocation of secondary metabolites among cladodes with different age. We performed a field study taking samples of vegetative tissues from cladodes of different orders during eight months, and a field experiment, by covering either apical or basal cladodes with a fabric. We determined the content of 4-hydroxybenzoic acid (4-HBA), chlorogenic acid (CGA), quercetin (QUE) and salicylic acid (SA). 4-HBA and CGA followed the predictions of ODH. QUE followed an inverse tendency. SA did not show any tendency related either with the position of the cladode or the treatment (light vs. shade) however, its concentration was positively correlated with the concentration of 4-HBA. As we detected SA only in a low proportion of cladodes and 4-HBA in all cladodes, we hypothesize the conversion of the latter metabolite to the former one. Contrary to ODH, CGA presented lower concentrations in apical than in basal cladodes when co-occurred with SAL, and QUE was transferred from apical (younger) to basal (older) cladodes. In this study, we found contradictions in the premises and outcomes of both the Resource Availability Hypothesis (RAH) and the ODH, suggesting that a new hypothesis concerning the plant defense against stress factors should be proposed.

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