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1.
We present the first reported occurrence of canid coprolites from the late Pleistocene of central Mexico. The sample consists of five associated coprolites recovered from Quaternary deposits that crop out in southeastern Hidalgo, central Mexico. The material shows several of the typical features of canid feces, including elongated cylindrical shape, uncommon and nondistinct constrictions, and one tapered end. The coprolites are similar in size to feces of North American foxes, such as Vulpes macrotis, V. lagopus, V. vulpes, and Urocyon cinereoargenteus; likewise, their size might be comparable to those of the Pleistocene canid Canis cedazoensis. The content of the studied coprolites consists of numerous teeth and bone fragments referable to the pocket gophers Pappogeomys or Cratogeomys. The coprolite content is related to a mostly carnivorous diet comparable to that of C. cedazoensis, wolves (Canis lupus, C. rufus, and C. dirus), and some foxes (V. macrotis and V. velox). As a result, it is proposed that the potential trace maker of the coprolites could be a form similar to a carnivorous fox or a small dog. These trace fossils represent the first indirect evidence of canids in the late Pleistocene of Hidalgo and provide additional information regarding the geographic distribution of the Canidae in temperate areas of North America that now are part of central Mexico during the second half of the Pleistocene.  相似文献   

2.
In order to better determine the currentstatus of desert pupfish populations (Cyprinodon macularius macularius) in the LowerColorado River Basin of Mexico, bimonthly fishsampling and habitat evaluations were carriedout from September 1996 to August 1997 in sixlocalities of Baja California and Sonora.Desert pupfish were collected using minnowseines and traps. Four sampling sites are inSonora, in shallow marginal habitats of theCiénega Santa Clara (Hunters' Camp, Outletof the Welton-Mohawk channel, El Doctor andFlor del Desierto) and two are in BajaCalifornia (Cerro Prieto and streams south ofCerro Prieto). The most abundant fish speciessampled was native desert pupfish (C.macularius, 59%) followed by sailfin molly(Poecilia latipinna, 19%), redbellytilapia (Tilapia cf. zilli, 10%) and western mosquito fish (Gambusiaaffinis, 7%). Significant temporalfluctuations in distribution and abundance ofdesert pupfish populations, as previouslyreported for these populations, was againdocumented. The main anthropogenic factorsaffecting distribution and abundance of desertpupfish populations in the Mexican portion ofthe Lower Colorado River Basin are progressivealteration of aquatic and riparian habitats, aswell as presence of exotic fishes that havecaused the displacement or elimination ofnative fish populations. Both habitat andpresence of the desert pupfish populations inthe study area are controlled by theperiodicity, quality and volume of dischargesinto the Mexican portion of the basin from theUnited States.  相似文献   

3.
Macrothrix mexicanus sp. nov. is described from central México, a transition zone between the nearctic and neotropics. All localities where it was found are over 1800 meters above sea level. It shows many resemblances with M. laticornis, M. camjatae and M. rosea but is characterized by a persistent dorsal tooth on the valve keel, a spinous papilla on the basipodite of the antenna, the second thoracic limb with a long conical sensillum between scraper 1 and the gnathobase, the endopod of trunk limb IV having two setae; the postabdomen with the dorsal margin bilobed, and the distal segment of the seta natatoria which is unusually long.Abbreviations used on figures EN Endopodite - EP Epipodite - EX Exopodite - IDL Inner distal lobe - ODL Outer distal lobe - GT Gnatobase - E1 Endite 1 - E2 Endite 2 - E3 Endite 3  相似文献   

4.
A new aquatic, arsenic-tolerant species ofEleocharis (Cyperaceae) endemic to Chihuahua, Mexico, is described and illustrated. It belongs toEleocharis sect.Eleogenus seriesMaculosae. A key for the species ofEleocharis sect.Eleogenus from Mexico is included.
Resumen  Sc describe e ilustra una nueva especie deEleocharis (Cyperaceae) acuática, tolerante a altas concentraciones de arsénico, y endémica de Chihuahua, México. Forma parte de la secciónEleogenus serieMaculosae. Se incluye una clave para las especies deEleocharis sect.Eleogenus de México.
  相似文献   

5.
The type specimen of Toyotamaphimeia machikanensis (Diapsida, Crocodylia) from the Osaka Group (Plio-Pleistocene) of Osaka Prefecture, Central Japan, shows multiple abnormalities. The anterior third of the mandible was amputated and shows signs of healing. The right tibia and fibula were fractured, and each of them was later fused in dislocated position with callus formation. Additionally, there are two puncture marks on a dermal scute. Based on the morphologies of these pathologies, the fauna of the community in which this animal lived, and the behavior of extant crocodilians, it is suggested that this individual survived its injuries sustained during multiple intraspecific fights for territoriality or mating.  相似文献   

6.
Paloma White 《Anthrozo?s》2018,31(5):615-625
This paper examines the regulation and management of dogs in the Mexican municipality of Isla Mujeres. It shows how dogs, on Isla Mujeres, are managed under a neoliberal framework of a decentralized government which relies on the personal responsibility of citizens and the outsourcing of essential services to non-government and private organizations. In so doing, this paper demonstrates some of the political and organizational contexts within which human-dog relationships are situated. In particular, it analyzes the ways that humans relate to dogs within a regulatory and socio-political framework. This paper is based on a six-week period of ethnographic research, primarily situated within an international non-government animal rescue organization. From this vantage point, this paper shows how neoliberal approaches to dog management within the municipality creates tension between personal and governmental responsibilities and fosters reliance on the third sector to provide animal welfare and wellbeing services. Within this network of distinctly human relationships, the wellbeing of animals is obscured, leading to a series of animal welfare crises within the municipality.  相似文献   

7.
J. M. Campbell 《ZooKeys》2014,(415):269-293
The species of the genus Charisius Champion, from Mexico and Central America are reviewed. The flightless genus Narses Champion, with one included species, N. subalatus Champion, is placed in synonymy with the genus Charisius. Four new species are described and illustrated, C. granulatus and C. punctatus (from Guatemala) and C. apterus and C. howdenorum (from Mexico). Charisius subalatus (Champion) is redescribed and illustrated. The species C. interstitialis Champion is placed in synonymy with C. zunilensis Champion. The genus is redescribed to include the four new species and N. subalatus. New distributional records are presented for all other species of the genus and a revised key is presented for identification of all the species of the genus.  相似文献   

8.
This paper analyzes the immensely popular animated film Ratatouille as a social and cultural document. It begins with a recapitulation of the movie's story line – a saga of an astute, ambitious and talented rat, who becomes transformed into an accomplished haute cuisine chef. The film illustrates recent anthropological writings on the central role of cooking in human evolution. It also shows how varieties of cooking and table manners provide key indications of the civilizing process. Ultimately, Ratatouille explores distinctions and similarities between “man and beast”. It communicates the idea that all living creatures share more in terms of aptitude and feeling than divides them.  相似文献   

9.
10.
Heron  Gayle A. 《Hydrobiologia》2002,480(1-3):145-154
A new species, Oncaea frosti, is described and compared to O. venusta Philippi and O. venella Farran. The three species are closely related and difficult to distinguish, except for the differences in size of females and males and dorsal dilation of pediger 2 of females of O. frosti.  相似文献   

11.
Comerinia chuetolamina gen. & sp. nov. was collected from a cargo of dried Daphnia imported to Britain from Mexico. Females can be distinguished from all others described in the family Acaridae in that setae 14, 15 and d5 are flattened dorsoventrally over most of the basal half. This region appears blade-like, bearing numerous strong pectinations along the ventral side. Males may be recognized by a series of characters, some of which reflect a close relationship with Forcellinia Ouds., 1924 and others with Tyrophagus Ouds., 1924. The position of the new genus in a commonly used key to adults of the family Acaridae is indicated.  相似文献   

12.
Galve (Teruel, Spain) is a town in the interior of a synclinal fold with Upper Jurassic marine limestones along its flanks, and, in its core, Upper Jurassic–Lower Cretaceous continental and shoreline sediments crop out. The core sediments cover an area about 8 km2, and contain a concentration of sites with footprints, bones, and eggshells of dinosaurs. The footprints are both shafts and natural casts. Some casts are attributed to stegosaurs (Deltapodus). The Deltapodus casts are characterized by features that allow us to make direct observations on the skin formed by polygonal scales, and ellipsoidal “hooves,” as well as deductions on the movement of the limbs during walking. According to the opinion of some authors, dinosaur footprints are indicators of the motion of their limbs and sometimes of the whole body. So far, results have been deduced from theropod, ornithopod, and sauropod footprints. This article shows the results obtained from analis of the aforementioned Deltapodus casts, i.e., forelimb movement similar to that of the forelimbs of sauropods, and the rigid structure of the autopodial part of the hind limb.  相似文献   

13.
Thirteen populations of Thorea were analyzed from central Mexico and south‐eastern Brazil. All populations were considered as belonging to a single species [Thorea hispida (Thore) Desvaux], with wide variation of morphological features. Secondary branches varying in frequency were observed in several populations with an overlapping in the range of branch density for Thorea violacea Bory and T hispida (0–9 and 11–41 per 30 mm, respectively). As this is the most distinguishing character and on the basis of the overlapping (within a same population or even a single plant), we regarded T. violacea as a synonym of T hispida.‘Chantransia’ stage in culture, as well as gametophyte and carposporophyte were described in detail. We confirmed tine coexistence of asexual monosporangia with sexual reproductive structures (carpogonia and spermatangia) and carposporangia. Size, content, arrangement and chromosome number were the most distinctive characteristics among spermatangia, carposporangia and monosporangia. Monosporangia can be promptly differentiated from spermatangia by their granulated content and larger size but they are similar to carposporangia in shape and size; however, monosporangia are not arranged in fascicles. Structures resembling bisporangia were observed in female plants of some populations. Chromosome numbers were n = 4 for spermatangia and fascicle cells, and 2n ca 8 for gonimoblast filaments, carpospores and the ‘Chantransia’ stage cells. The populations of Thorea from central Mexico and south‐eastern Brazil corroborated the known world distribution for T. hispida, consisting dommantly of tropical to subtropical rainforests, sometimes extending into warm temperate areas. Thorea hispida occurred in warm (temperature 17.6–28.O°C), neutral to alkaline (pH 7.0–8.0), high ion content (specific conductance 59–2140 μS cm?1), moderate flowing (current velocity 17–43 cm/s) and shallow waters (depth <50cm); these data are essentially similar to previous reports.  相似文献   

14.
Sicyos lirae is described as a new species from Chiapas, Mexico, and Guatemala. It grows in zones with primary or secondary montane rain forest at elevations between 1400 and 3800 meters. In Guatemala the species is commonly called “güisquil de ratón.” It is similar toSicyos galeottii Cogn., from which it differs in blade consistency, shape of the stigma lobes, and several important ovary and fruit characters.  相似文献   

15.
In the present study, two new species of Gyrodactylus are described from Profundulus oaxacae, a fish endemic to the Pacific slope of Oaxaca State, Mexico. Fishes were collected within their distribution range in 5 localities in the Atoyac-Verde River. Gyrodactylus montealbani n. sp. and G. zapoteco n. sp. were erected and characterized morphologically (sclerites of the attachment apparatus and the male copulatory organ) and molecularly (sequences of the Internal Transcribed Spacer region of rDNA). The haptoral sclerites of the new species are similar to those of Gyrodactylus iunuri and Gyrodactylus tepari, both recently described from the goodeid fish Goodea atripinnis, from the Mexican States of Jalisco and Querétaro, respectively; and to Gyrodactylus xtachuna described from the poeciliid Poeciliopsis gracilis in Veracruz State, Mexico – nonetheless, these species can all be discriminated based on their marginal hook morphology. Specimens of G. montealbani n. sp. and G. zapoteco n. sp. were sequenced, and were aligned with sequences of 25 other Gyrodactylus spp. Both Maximum likelihood and Bayesian inference analyses indicated that the two new species are members of independent, well-supported lineages – these are the first Gyrodactylus species described from Profundulus oaxacae.  相似文献   

16.
The objective of this study was to contribute to the knowledge of the syllids distributed in the eastern coasts of Mexico (Gulf of Mexico and Caribbean) taking into consideration their composition, distribution and diversity. Sampling was done at 77 stations including 49 in soft bottoms (terrigenous and carbonate sediments), and 28 in hard bottoms (coralline substrates) sampled in nine reef zones included in three reef systems (Veracruz, Campeche and Cozumel). In all 2084 individuals were collected (13.5% in soft sediments and 86.4% in coralline areas). Forty-five species were identified: 31 in soft bottoms and 38 in corals, with 21 species common to both types of environments. In soft bottoms, the highest species richness and diversity were found in the Carbonate Zone, while syllids were uncommon in the Terrigenous Zone. In hard bottoms, the highest density, species richness and diversity values were found in the Veracruz Reef System, followed by the Campeche Bank and Cozumel Island Reef Systems. The dominant species in soft bottoms were Haplosyllis spongicola, Exogone lourei, Typosyllis cornuta and T. papillosus, whereas T. alosae, T. corallicola, T. cornuta and H. spongicola dominated in hard bottoms. The importance and success of the syllids in both soft bottoms and reef environments, particularly in those of the Gulf of Mexico is emphasized.  相似文献   

17.
Thirteen new species of the genusStevia are described and illustrated from Mexico:S. chilapensis, S. coahuilensis, S. crassifolia, S. ecatepecana, S. filodecaballoana, S. mascotensis, S. mexicana, S. oaxacana, S. oligophylla, S. potosina, S. rotundifolia, S. scabrelloides, andS. viejoana. In addition, two varieties,Stevia aschenborniana Sch. Bip. ex Klotzsch var.occidentalis Grashoff andS. palmeri A. Gray var.constricta Grashoff are herein redefined as being distinct species,S. occidentalis andS. constricta stat. nov.Stevia mexicana resemblesStevia trifida Lagasca but differs in the habit.  相似文献   

18.
At Cedro Peak (Manzanita Mountains, central New Mexico), the Pennsylvanian succession is divided into four formations: Sandia, Gray Mesa, Atrasado, and lower part of Bursum. The sampled limestones of the Gray Mesa and Atravasado formations yielded three age distinctive fossil assemblages: (a) latest Atokan/early Desmoinesian; (b) late early Desmoinesian, and (c) middle Virgilian. The calcareous algae, incertae sedis algae and cyanobacterial-foraminiferal consortia are described here. The following new taxa are named: Epimastoporaceae n. fam.; Anthracoporellopsis novamexicana n. sp.; Tubiphytidae n. fam.; and Latitubiphytes n. gen.  相似文献   

19.
A new genus and new species of the family Darcythompsoniidae Lang (1936), and a new record of Darcythompsonia fairliensis (T. Scott, 1899), from a coastal lagoon in the south-eastern Gulf of California (Mexico), are reported and fully described and illustrated. Pabellonia olganoguerae gen. no v., sp.nov. shares features with Darcythompsonia T. Scott, 1906, such as the presence of a dimorphic second endopodal segment of the male second swimming leg, and with Kristensenia Por, 1983, the lack of sexual dimorphism in the caudal rami, anal operculum and urosomites. Thus it is considered closely related to these genera, and to represent a third component of mis lineage. Some notes on the biogeography of Darcythompsonia T. Scott, 1906, are also presented.  相似文献   

20.
Human tracks discovered in 1874 at a site named El Cauce or Acahualinca near the shores of Lake Managua, Nicaragua, are the most famous and abundant human tracks in the Americas. They represent a landmark ichnological discovery during the late 19th century that generated much debate regarding their age and origins. Reported dates for the tracks range from 2,120 to 6,500 B.P. The site, which is now situated within the limits of Nicaragua's capital city of Managua, forms the basis of the Acahualinca Tracks Museum (Huellas de Acahualinca) and has been in place since 1953. However, it is still little known and has not been systematically studied, despite being an important window into Meso-American prehistory. Two exposures of a surface of volcanic ash reveal hundreds of human tracks comprising a minimum of 12 clearly defined trackways, and a trampled zone or path representing at least three more individuals, all heading in the same northwesterly direction. Tracks of deer, opossum and at least one bird are also present. Bison tracks collected from another nearby site (El Recreo) that is no longer accessible are on display at the museum. The Acahualinca tracks are noteworthy for the exceptional quality of preservation. We herein present the first maps of the two exposures, which combine to tell a story of human and animal activity along the shores of ancient Lake Managua several thousand years ago.  相似文献   

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