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1.
Leaves of two new plants are reconstructed from their isolated leaflets collected from the Oligocene Los Ahuehuetes locality near Tepexi de Rodríguez in Puebla, Mexico. The leaves of Pseudosmodingium mirandae Ramírez-Gardu?o et al. are compound imparipinnate with leaflets of variable morphology. The leaflets of five leaf morphotypes vary from narrow elliptic to lanceolate or lorate; they are symmetrical to slightly asymmetrical, with acute to attenuate apex, acute to cuneate base, and entire to serrate margin. Venation is simple pinnate craspedodromous, with secondary veins slightly curved near their base; secondary veins may dichotomize near the margin to become tertiary veins, and intersecondary veins are small and oblique to the secondary veins. A small number of leaflets assigned to Pseudosmodingium terrazasiae Ramírez-Gardu?o et al. are distinguished from P. mirandae by the leaflet shape, length&rcolon;width ratio, base shape, and apex angle. Morphological comparison of the fossil leaves with leaves of extant species of Anacardiaceae based on numerical analyses indicates a close similarity between P. mirandae and Pseudosmodingium multifolium Rose, while P. terrazasiae is more similar to Pseudosmodingium perniciosum (HBK) Engl. The presence of fossil species with extant relatives that are endemic to Mexico, along with previous reports, indicates that by the Oligocene, some lineages were already in place, although today they form part of the more xeric communities in southern North America.  相似文献   

2.
The Sierra Norte de Puebla, Mexico, is a region with biological and cultural diversity, where the use of local natural resources was increased by the relative isolation of the region until recent decades. There are more than 600 useful plants reported. In the Sierra Norte de Puebla at least six Begonia species are used as food. The objective of this paper is to report such species that are utilized for self-supply and for sale in local markets. The management includes gathering among wild populations, transplanting of rhizomes and vegetative propagation by leaves to establish and increase populations in home gardens and in coffee plantations.  相似文献   

3.
A complete skeleton of a new scincomorph lizard from the Early Cretaceous deposits of Tepexi de Rodriguez is described. Tepexisaurus tepexii gen. et sp. nov. is the best preserved early scincomorph and the first known taxon that is morphologically primitive to scincoids and paramacellodid lizards. The presence of pointed ventral parietal downgrowths, the coronoid overlapped anteriorly and posteriorly by the dentary and surangular, a small medial flange on the retroarticular process, and weak zygosphene and zygantrum articulations suggest scincoid relationships, but the absence of ventral and dorsal osteoscutes place Tepexisaurus as sister-group of this taxon. It shares the presence of + 30 closely packed teeth with the poorly known Upper Jurassic genus Saurillus and Pseudosaurillus , but differences in the coronoid structure, Meckelian groove and jaw proportions indicate that both taxa are distinct. Similar to Tepexisaurus , the absence of osteoscutes in Saurillus, Pseudosaurillus and Saurillodon place these taxa in a more primitive position relative to other paramacellodids which should be included within Scincoidea. Thus, Paramacellodidae as previously defined is a paraphyletic assemblage. The late presence of a pre-scincoid lizard in the Albian deposits of Tlayua can be correlated with the presence of sphenodontians and the relictual nature of the basal squamate Huehuecuetzpalli mixtecus. It gives additional evidence to support the hypothesis that Tlayua was a refuge for terrestrial archaic forms during the Albian.  相似文献   

4.
This paper describes the trade of dry medicinal plants in the southwestern area of the state of Puebla, Mexico. Gatherers who collect medicinal plants represent the poorest economic link in the trade chain. The critical socioeconomic situation of the human population is reflected in the state of the wild plants at the zone, as a result of an increase in their use for economic survival. The stock of medicinal plants handled by regional traders is an indicator of the abundance and diversity of the flora present in the zone, and permits a dynamic exchange of these products with regional traders from outside. Tracing the commercial path of six medicinal plants from the field to the market, only 6.17% of the consumer price, on average, was returned to the collectors. Most of the medicinal plants marketed and used in Mexico are wild plants. This fact, combined with the increasing demand that exists for medicinal plants in this region, create a potential environmental threat. Since this threat is a multifactorial one, involving the complex socioeconomic conditions in which rural workers and their families live, conservation programs for the wild flora (including reassessed gathering methods, production of selected medicinal species and protection of wild populations and market regulations of quality and equity) have to be applied within an organizational framework of the gatherers and peasants in the zone.  相似文献   

5.
Comparisons of age at menopause are made difficult by the different methodologies applied across populations. This study extended an opportunity to apply different methodologies to the same data to draw some preliminary conclusions about age at menopause in Puebla, Mexico. Among 755 women aged 28 to 70 interviewed in the capital city of Puebla, Mexico, 447 (59.6%) were naturally or surgically postmenopausal. Mean recalled age at natural menopause in Puebla (46.7 years) appears to be similar to mean recalled age at menopause in Mexico City (46.5 years), suggesting that age at menopause is similar in urban Mexican populations. However, median age at menopause computed by probit analysis was later in the city of Puebla (49.6 years) compared to the median age computed by the same method in the capital city of León, Guanajuato, Mexico (48.2 years). Median age at menopause computed by Kaplan-Meier survival analysis suggests that age at menopause in Puebla (50.0 years) is older still, and close to that of the United States (51.1 years). The differences in median ages at menopause in Puebla are solely due to methodological choices and highlight the difficulty inherent in making inferences across studies of age at menopause between biological and/or cultural groups. Factors associated with age at menopause offer another avenue for comparing and understanding variation in this basic biological process. In Puebla, smoking, low levels of education, and nulliparity are associated with an earlier age at menopause.  相似文献   

6.
Recently discovered fossil flowers from the Cretaceous Cerro del Pueblo and flowers and fruits from the Oligocene Coatzingo Formations are assigned to the Rhamnaceae. The Cretaceous flower, Coahuilanthus belindae Calvillo-Canadell and Cevallos-Ferriz, gen. et sp. nov., is actinomorphic with fused perianth parts forming a slightly campanulate to cupulate floral cup, with sepals slightly keeled and spatulate clawed petals. The Oligocene fossils include Nahinda axamilpensis Calvillo-Canadell and Cevallos-Ferriz, gen. et sp. nov. (characterized by its campanulate bisexual flower with stamens opposite, adnate to and enfolded by petals; and with the ovary ripening into a drupe), and a winged fruit assigned to Ventilago engoto Calvillo-Canadell and Cevallos-Ferriz, sp. nov. The flowers and drupe features indicate closer affinity to Zizipheae and/or Rhamneae, while the single samaroid fruit suggests the presence of Ventilagineae. However, the unique character combination in the fossil flowers precludes placing them in extant genera. Nevertheless, the history of the family is long and can be traced back to the Campanian. A detailed phylogenetic revision of the group that uses morphological characters from both extant and fossil plants is needed to better understand the significance of these records as well as other important fossils of the family.  相似文献   

7.
Tapirira chimalapana is a new species of tree common in the rain forests and lower montane forests of the Isthmus of Tehuantepec in the Mexican states of Veracruz and Oaxaca. It is most similar to the AndeanT. guianensis Aubl. subsp.subandina Barfod &; Holm-Niels. but differs from this and all other congeners by having larger petals on pistillate flowers than on staminate flowers and by pubescence features. Details of field characteristics, distribution, ecology, phenology, germination, and local names and uses are included.  相似文献   

8.
The compressed basidiocarp of a fungus belonging to Geasteraceae (Lycoperdales; Gasteromycetes) was recovered from the plant-bearing Cenozoic strata of the Pié de Vaca Formation, Puebla, Mexico. The fossil specimen consists of an open exoperidium with ten triangular rays, and a central, circular endoperidium with an eccentrical ostiole and irregular surface relief. Scanning electron microscopy revealed a delicate reticulum on the surface of rays and on samples of the endoperidium. An acetolyzed fragment of the endoperidium yielded a few fungal spores, and similar spores were also obtained from an acetolyzed rock fragment adjacent to the fossil specimen. The fossil fungus exhibits the characteristics of extant earthstars; morphological comparison between the extant and the fossil earthstar and the type of spores obtained from the endoperidium of the latter indicate its affinity with Geastrum, although uncertainty in diagnostic characters preclude its assignment to a living species. The report of a complete basidiocarp of Geastrum from the Cenozoic of Puebla may contribute greatly to the knowledge about the spatial distribution and evolutionary history of Geasteraceae and Lycoperdales.  相似文献   

9.
The amber of Simojovel de Allende, Chiapas, Mexico, of Late Oligocene-Early Miocene age, has yielded a new flower representing the Meliaceae. The flower of Swietenia miocenica Casta?eda-Posadas & Cevallos-Ferriz sp. nov. is characterized by small size; free calyx composed of five glabrous lobes, ciliolated along the margin lobes; corolla composed of five free, contortedly inserted petals with ciliolated margins; cylindrical staminal tube ending in 10 acuminate or toothed accessories and 10 sessile anthers; and a discoid stigma divided in five lobular stigmatic glands. The morphology of S. miocenica is well represented among Meliaceae. Although the new species shares many characters with Swietenia microphylla, small differences in the length and width of petals and the length of staminal tube support its recognition as a new species. The presence of this genus demonstrates the establishment of tropical communities in southern Mexico by the early Miocene and highlights the influence of the northern hemisphere flora on the extant neotropical flora of the area.  相似文献   

10.
11.
A fossil assemblage of diverse megascopic benthic algae is well preserved on bedding planes in black siliceous shales of the Neoproterozoic Lantian Formation (upper Sinian) at Lantian village, Xiunng county, Anhui Province, South China. Based on morphological differences, 12 taxa are recognized. Most specimens show both a holdfast and a vegetative thallus, some with dichotomous branching, which reveals that they are multicellular benthic algae. Each type presents a certain morphological appearance, e.g., spheroidal - Chuaria sp., filamentous - Doushantuophyton rigidulum , fan-like - Flabellophyton lantianensis. Four to six different benthic forms and more than 15 individuals are well preserved on the same bed with an area less than 150 cm2. These confirm that a great morphological evolutionary radiation of seaweeds took place no later than the Lantian epoch, with an absolute age around 570 Ma. Growth cycles in Flabellophyton strigata n.sp. reveal that periodical events, such as seasonal variations, occurred in that epoch. A benthic assemblage consisting of three differentiated macroscopic remains is similar to the Miaohe Biota reported from the Doushantuo Formation of the Yangtze Gorges 1200 km away, allowing biostratigraphic correlation of both of these Neoproterozoic Formations.  相似文献   

12.
Tetramorium notomelanum sp. n. is described from the Tehuacán Valley, state of Puebla, México. Its distribution and relation with other species of the tortuosum-group is discussed. The new species of Tetramonium is described from workers, and distinguished from others of the group by several characters: i) black coloration of the body; ii) size: T. notomelanum sp. n. is smaller than T. hispidum (Wheeler), T. mexicanum Bolton and T.spinosum (Pergande), but larger than T. bicolorum Vásquez-Bola?os and T. placidum Bolton; iii) length of the hairs of the dorsal of the head are equal to the diameter of eye; iv) the length of the hairs on the scape and tibiae less than the width of the appendage where they are located. This is the second species of the tortuosum group of Tetramorium found in the State of Puebla, and the fourth recorded in Mexico.  相似文献   

13.
We present a first glimpse of the mean height of men in eighteenth century Mexico based on evidence from the Revillagigedo Census of 1791–1792. Mexican men were shorter than those of Europe and North America. For example, contemporary French men were about 165 cm and US men were about 174 cm; in contrast, Mexican men were about 162 cm. Men of higher income were taller than those in the middle and lower income strata. Mestizos (a mix of whites and Indians) were shorter than the rest of the recruits belonging to other ethnic categories.  相似文献   

14.
A micropaleontologic study was carried out from samples collected along a section that crops out in the Santiago Coatepec Stream, located in the southeast of the state of Puebla, Mexico. The sedimentary sequence begins with a reddish conglomerate. Above, thick and thin layers of grey-greenish sandstones that continue in fine-grained, calcareous sandstones, and, finally, in limestones. The reddish conglomerate may represent a continental environment, and the marine transgression began with the sandstone deposit that contains a marine association of Invertebrates such as Trigonids (Myophorella sp.), and other Mollusks such as Trichites sp., Ostreids and Gastropods, Echinoderms, and Sponges as Cladocoropsis mirabilis. This sequence also provides a rich assemblage of larger Foraminifera as well as Algae, which is reported for the first time in this site. The larger agglutinated Foraminiferal assemblage is composed of Alveosepta jaccardi, Pseudocyclammina lituus, Everticyclammina virguliana, Rectocyclammina chouberti, Choffatella cf. Ch. tingitana, Mesoendothyra croatica, Nautiloculina oolithica, Freixialina planispiralis, Audienusina fourcadei, Placopsilina sp., Pseudocyclammina sp., Meandrospira sp. and Lenticulina sp. All those taxa were adapted to special paleoecological conditions, such as a continuous terrigenous input. The Algae are Marinella lugeoni, Pseudoepimastopora jurassica, Permocalculus sp., and Halimeda sp. The stratigraphic distribution of the larger benthic Foraminifera allow us to propose a Kimmeridgian age for the studied sequence. The opening of the Atlantic Ocean permitted the colonization of its margins by the larger Foraminifera during this time. The data provided by the larger Foraminifera, the Algae, and the lithology may suggest an internal platform environment of warm shallow water. This foraminiferal association is constituted by cosmopolitan species which are frequent in the Tethyan Realm.  相似文献   

15.
Gene frequencies and admixture estimates in the state of Puebla, Mexico   总被引:4,自引:0,他引:4  
Three hundred ninety-three individuals from the Universidad Autónoma de Puebla and its University Hospital were studied to determine the distribution of ABO, MN, Rh-Hr, Duffy, and Diego blood groups; red cell hemoglobin and glucose-6-phosphate dehydrogenase variants; and serum haptoglobins, albumins, and factor Bf types. With the results we estimated that the proportions of black, indian, and white genes are 10.7%, 56.3%, and 33.0%, respectively, in a trihybrid model. Reasons are given as to why the black ancestry may be artifically high, and it is pointed out that independent confirmation with other markers is needed before the figure can be accepted as a true value.  相似文献   

16.
Adult butterflies and moths (Lepidoptera) use their proboscises to feed on flower nectar and other types of liquid food. Aphids frequently secrete honeydew from their anuses, attracting various types of insects, such as ants. Adult lepidopterans are also known to feed on aphid honeydew. However, very few studies have clarified the species composition and morphology of moths feeding on aphid honeydew. In late June 2017, we found nocturnal moths sipping honeydew secreted by Shivaphis celti and Sitobion cornifoliae (Hemiptera: Aphididae) on leaves of Celtis sinensis (Cannabaceae) and Cornus kousa (Cornaceae), respectively, at the edge of a secondary forest in central Japan. The moths were observed to uncoil their proboscises and feed on honeydew on the leaves. No moths were observed to feed on honeydew directly from aphids. Nocturnal moths of 60 species (11 families) and 16 species (7 families) were collected from honeydew on Ce. sinensis and Co. kousa leaves, respectively. Eleven moth species were shared between the two types of honeydew. The most abundant species, Oncocera semirubella (Lepidoptera: Pyralidae), accounted for 44.7% of all individuals. The sex ratio of O. semirubella was female biased. Of the 65 moth species collected on aphid honeydew, 52.3% (34 species) have been previously reported to visit flowers. Moths visiting honeydew had relatively short proboscises and small body size. These results suggest that aphid honeydew is an important, accessible food resource for moths of small size.  相似文献   

17.
18.
Among the Pleistocene localities of the Sierra de Atapuerca, the site called Sima del Elefante is famous for having delivered in its lower level (TE-LRU) some hominid remains currently considered the oldest in Western Europe (about 1.2 Ma). In its upper part (TE-URU), this site has fossiliferous levels pertaining to the late Middle Pleistocene (350-250 ka). Here we describe for the first time the amphibians and reptiles of these upper levels (TE18 and TE19), which have proved to be one of the richest assemblages of all the localities of the Sierra de Atapuerca. The faunal list is composed of 18 taxa made up of urodeles (Salamandra salamandra and Lissotriton helveticus), anurans (Discoglossus sp., Alytes sp. Pelobates cultripes, Pelodytes punctatus, Bufo bufo, Bufo calamita, Hyla arborea and cf. Rana sp.), a terrestrial tortoise (Testudo s.l.), lizards (Lacerta s.l., Podarcis sp. and Anguis fragilis) and snakes (Natrix natrix, Natrix maura, Coronella cf. girondica and Vipera latasti). For the first time, the genera Lissotriton, Discoglossus and Podarcis are mentioned in the Pleistocene localities of the Sierra de Atapuerca. TE19 also corresponds to the earliest mention for L. helveticus in the Iberian Peninsula. With the exception of tortoises, all these species are currently present in the province of Burgos, and thus suggests that the herpetofauna has a modern aspect since the Middle Pleistocene. This association of amphibians and reptiles suggests a slightly warmer climate than the current one, but may correspond to a “cold and dry” period if compared with other Pleistocene localities of the Sierra de Atapuerca. The landscape was probably composed of a gallery forest along a quiet water river within a Mediterranean environment alternating laterally between dry meadows, rocky or stony areas and open scrubland.  相似文献   

19.
20.
FANNING, U., EDWARDS, D. & RICHARDSON, J. B., 1992. A diverse assemblage of early land plants from the Lower Devonian of the Welsh Borderland. Nine rhyniophytoid taxa are described from an early Gedinnian locality ( middle micromatus-newportensis spore Biozone) near Ludlow, England. They include Cooksonia pertoni, C. hemisphaerica, C. cambrensis, Tortilicaulis transwalliensis and three new taxa, Salopella marcensis sp. nov., Uskiella reticulata sp. nov. and Tarrantia salopensis gen. et sp. nov. Isolated sporangia of reniform shape, and those subtended by short lengths of axis, contain spores of Apiculiretusispora type and may belong to C. caledonica or Renalia . Morphologically distinctive forking, terminal sporangia lacking identifiable spores are not placed in a new taxon, because evidence based on in situ spores from elsewhere suggests they may belong to Salopella . Structures previously interpreted as clusters of sporangia of Yarravia- type are shown to be ± globular sporangia longitudinally split into valves. Sterile axes are dominated by smooth forms; although rare examples possess small enations. Tracheids have not been seen in axes of fertile specimens nor in sterile coalified compressions. A single pyrite permineralization contains tracheids of zosterophyll type. The assemblage demonstrates diversity among rhyniophytoids in the early Devonian and the existence of low vegetation 'alongside' the much larger zosterophyll dominated type.  相似文献   

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