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The first lapsine jumping spider (Salticidae: Spartaeinae) is recorded from Chiapas amber, Mexico. This specimen is a new fossil species belonging to the extant genus Galianora, with an age of 23 My (Miocene-Aquitanian). This is the first lapsine in the the fossil record, a group not previously recorded in the extant spider fauna from Chiapas. The geographical range of the genus extends towards the north of the Neotropical region thanks to this fossil representative. This new species, and previous records of salticids in Mexican amber, are consistent with a radiation of Salticidae in the Neogene, with both Neartic and Neotropical implications. The presence of Galianora in amber, predicts its presence in the extant Chiapas spider fauna. Based on the fossil record, it is possible that extinct genera of spiders may still remain in the region and probably survived the geological evolution of Central America. It is also possible that Chiapas was a center of origin for several species of Araneae; therefore, it is necessary to intensify araneofaunistic studies focused on analyzing the richness and diversity of spiders in Chiapas, using phylogenetic studies (including fossil taxa) to test this hypothesis. [ABSTRACT FROM AUTHOR]

In this study, the results of the identification of five plant fossils included in amber from Simojovel, Chiapas are shown. The vegetal structures studied correspond to two flowers which belong to the Arecaceae Family; two compound leaves (leaflets) which belong to the Fabaceae Family, and an isolated leaf, which belongs to the Myrtaceae Family. The identification and description of these kinds of structures strengthen the present records on the distribution of these family plants during the Miocene in Chiapas. This study contributes to widen the knowledge of the diversity of vegetal remains included in the amber from Chiapas. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuaternario y Geomorfología is the property of Cuaternario y Geomorfologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we describe two fossil remains of squamate reptiles found in Middle Pleistocene outcrops at the northern marine cliffs of the city of Mar del Plata (Buenos Aires province). The specimens were found forming a taphocenosis with remains of other microvertebrates (amphibians, mammals and birds). The reptiles recognized in the association are represented by remains of an undetermined colubrid, and the anguid Ophiodes sp. This latter finding represents the first fossil record for the family Anguidae exhumed in Argentina. [ABSTRACT FROM AUTHOR]

Paleobotany research has developed multiple analytical frameworks using plant macrofossils as a tool for paleoclimate inference. These frameworks can be broadly divided into two groups: the taxon independent approach (TIA) and the nearest living relative (NLR). The TIA studies climate-driven phenotypic variation in extant plants and extrapolates the relationship between climate and structure to make paleoclimatic inferences. The NLR, on the other hand, relies on the taxonomic identification of the species in fossil assemblages to assign them the climatic tolerances of their nearest living relatives. Both frameworks have proven to be useful but have intrinsic flaws due to the nature of the data used and the particular methods employed. Our target here is to highlight the significance of these frameworks, but also to point out that they do not always provide unequivocal paleoenvironmental data, which is the result of differences in both scale (geographic, temporal and taxonomic) and taphonomical processes. Here we illustrate some of the advantages and flaws of both frameworks using three examples of paleoclimate inference for some Mexican localities. In this paper we briefly review as well some of the relevant research relating leaf and wood structure to environmental variation that has served as the foundation for the field. [ABSTRACT FROM AUTHOR]

Taphonomy has undergone substantial changes within its field of study during the last decades, particularly concerning the understanding of the fossil record as an important source of information about the genesis of materials that occurs over temporal scales. Plant taphonomy is the study of the transition of plant remains from biosphere to lithosphere; this transition begins with the initial abscission of plant organs, followed by transportation, eventual deposition, burial and final lithification. Among these taphonomical stages, different processes and factors affecting taxonomic composition and type of the resultant fossil deposit can be recognized. The main goal of this paper is to provide an approximation of the different stages of the plant taphonomic process, highlighting the influence of transport, preservation, reworking and temporality potentials, and the main role of different sedimentary environments in the formation of plant fossil assemblages. The intrinsic plant nature along with the spacial discontinuity of sedimentary settings, their temporality and the variability of physical, chemical and biological factors during diagenesis, provide a complex interaction, essential for the understanding and interpretation of their fossil record. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Daena: International Journal of Good Conscience is the property of Spenta University Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)