首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
A preliminary account of Entolomataceae from Costa Rica is presented. Three new taxa are described, two inClitopilus, one inRhodocybe, and three new combinations are proposed inInocephalus. Five taxa ofClitopilus are reported for the first time from Costa Rica and a key to species is provided. Four species ofRhodocybe are discussed and a key to the six species known from Costa Rica is also provided.Alboleptonia earlei, Inocephalus murraii, Inocephalus quadratum, Rhodocybe incarnata andRhodocybe pseudonitellina are now known to occur in Costa Rica.  相似文献   

3.
4.
Centruroides schmidti Sissom, 1995 is the new identification designate of the scorpions previously known as C. thorelli (Kraepelin, 1891) in Northwest Costa Rica. The geographical distribution of the species in this country is established on the basis of new collected material. Its distribution includes the Pacific slope of the Guanacaste volcanic range, and the Pacific and Atlantic slopes of the Tilarán volcanic range between 50 and 775 m elevation above sea level, within the Costa Rican Guanacaste and Alajuela provinces.  相似文献   

5.
Noel H. Holmgren 《Brittonia》1978,30(2):182-194
The mountains of Costa Rica and western Panama constitute a natural floristic region that is inhabited by six species ofCastilleja.Castilleja talamancensis, C. lentii andC. tayloriorum are described as new. The remaining three areC. arvensis,C. irasuensis andC. quirosii. All butC. arvensis are endemic to the area. The six species are keyed, described, illustrated, mapped and documented with literature and specimen citations.  相似文献   

6.
This study analyzed the publications of authors from Costa Rican institutions that were included in the Science Citation Index (SCI) during 1999-2001. Out of the 722 references detected, distributed in 328 journals, 90.7% corresponded to original research articles. The total productivity figures showed a moderately increasing trend, both in absolute and population-adjusted terms, in concordance with previous data recorded for the period 1980-1998. The contribution of Revista de Biología Tropical to these figures corresponded to 10.0%, 8.9%, and 19.1%, for the years 1999, 2000, and 2001, respectively. The subject distribution of articles followed a similar pattern to that described for 1980-1998, with a predominance of biomedical (33.3%) and biological (27.5%) sciences, followed by agronomical (15.5%) sciences, chemistry (13.6%), physics (5.0%), geological sciences (3.6%), and mathematics (1.5%). Citation analyses for individual publications (up to July 15, 2002) revealed that only 45.2% of the articles had been cited at least once. The ten most cited references were analyzed, varying from 26 to 114 citations. The average citation per article was 2.60, and the average number of authors per article was 2.92. In agreement with data from 1980-1998, the University of Costa Rica appeared as the institution with highest productivity of SCI publications during 1999-2001, with a contribution of 50.0%. The percentage of publications performed without the participation of foreign co-authors showed a change in its decreasing trend of 1980-1998, stabilizing near the range of 25-30% during the period 1999-2001.  相似文献   

7.
8.
John F. Utley 《Brittonia》1981,33(4):581-586
Two new species ofVriesea with pendent inflorescences,V. uxoris andV. vietoris, are described from the mountains of Costa Rica, and their relationships in the genus are discussed.  相似文献   

9.
Chimpanzees and capuchins demonstrate greater varieties and higher rates of tool-use when compared to other non-human primates. Although capuchins have been studied extensively in captivity, data on their tool-using behavior under free-ranging conditions are limited. This is the first long-term field research to systematically study complex object manipulation in capuchins. The aims of this research are 1) to examine the types, rates, and contexts of tool- and object-use in free-ranging capuchins and 2) to determine if free-ranging capuchins' object manipulation behavior is comparable to the behavior exhibited by captive individuals. Data on 3 troops of white-faced capuchins (Cebus capucinus) were collected from February 1995 to January 1996 at Palo Verde, Costa Rica. Data were collected using focal animal and ad libitum sampling techniques. Any observed incident of tool-use and object-use was recorded. No tool-use was observed during the 11-month study. Object-use (pound, rub, and fulcrum-use) occurred at a rate of 0.19/hr and made up less than 1% of the monkeys' time (there were no differences among the age/sex classes). The results indicate that free-ranging capuchins do not exhibit the range of tool-using behavior demonstrated by their captive counterparts. This may be the result of differential motivational responses to objects, arboreal lifestyle, absence of adequate tool material, and/or absence of food resources that require extraction involving tool-use. Am J Phys Anthropol 106:311–321, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

10.
Beginning in early 2006, an ocular disease of unknown etiology was routinely observed in American crocodiles (Crocodylus acutus) inhabiting the highly polluted Tarcoles River in west-central Costa Rica. We examined the nature and incidence of ocular disease in Tarcoles crocodiles and assessed the possible association between the disease and accumulation of chemical pollutants in diseased individuals. During 12-15 September and 12-13 December 2007, crocodiles were captured and examined for ocular disease and sampled to determine environmental contaminant accumulation. Three of 11 (27.3%) crocodiles captured (all males) exhibited unilateral ocular disease, primarily characterized by corneal opacity and scarring, anterior synechia, and phthisis bulbi. Multiple pollutants were detected in crocodile caudal scutes (organochlorine pesticides [OCPs] and metals), crocodile blood (OCPs), and sediments (OCPs and metals) from the Tarcoles, but no associations were found between contaminant accumulation and the incidence of eye disease. On the basis of the limited number of diseased animals examined and the potential exposure of crocodiles to pathogens and other pollutants not targeted in this study, we cannot rule out infection or chemical toxicosis as causes of the eye lesions. However, circumstantial evidence suggests that the observed ocular disease is likely the result of injury-induced trauma (and possibly secondary infection) inflicted during aggressive encounters (e.g., territorial combat) among large adult crocodiles living at relatively high densities.  相似文献   

11.
A five-years long study aiming to describe the basic genetic epidemiology of the dystrophinopathies in Costa Rica recruited 31 patients with clinical symptoms of DMD/BMD at the National Children's Hospital (HNN). This center is the obligate reference hospital of the national health system for genetic diseases, however, the geographic origin of the patients, a low percentage of deletions and a high proportion of de novo mutations found among them indicate that a significant ascertainment bias impedes a substantial scientific approach to confront and alleviate the problems posed by these severe diseases in Costa Rica.  相似文献   

12.
Costa Rica has experienced a marked reduction in infant mortality--both in the neonatal and post-neonatal components--in the last decade. The decline could be related to improvements in the pattern of fetal growth. The present report analyses the birth weight of newborns from a random sample of all births in the Republic of Costa Rica during 1970 and 1975. While the average birth weight in that period was 3100 grams, the prevalence of low birth weight neonates decreased from 9 to 7 per cent in five years. The provinces of Limon and San Jose exhibited the highest frequency of low birth weight. Women 20 to 29 years old had babies with better or optimal body weight. Age, marital status and occupation of the mother appeared correlated with birth weight. A relationship between changes in fetal growth and changes in maternal, perinatal and neonatal mortality is apparent. The present situation of birth weight places Costa Rica among the countries in transition with a clearer perspective to attain an even higher infant survival in the near future. In this regard, several measures oriented toward prevention of low birth weight are recommended.  相似文献   

13.
Habitat use by squirrel monkeys (Saimiri oerstedi) in Costa Rica   总被引:1,自引:0,他引:1  
This paper analyses movement patterns, habitat preferences, activity schedules, and dispersion of troop members in squirrel monkeys (Saimiri oerstedi) in relation to seasonal changes in food abundance in a Costa Rican tropical wet forest. Secondary forest was the preferred habitat and use of primary forest and late successional forest was limited primarily to seasons when food availability was low. Range area differed between seasons, varying from 79 to 110 ha, and totaling 176 ha over 11 months. The number of hectares used, hourly rate of group movement, and proportion of time spent foraging each season were all negatively related to relative food abundance. There was a tendency to spend less time in foraging activities in the middle of the day and to spend more time exclusively in travel at dawn and dusk. In all seasons dispersion was least when the troop was travelling and it was generally greatest during seasons of low food abundance. Measures of the allocation of time by the troop to food-related activities and the extent of troop dispersion each season were consistent with estimates based on behavior sampling of individuals.  相似文献   

14.
Paullinia fournieri, a new species from Costa Rica is described, illustrated, and its relationships to other species are discussed.  相似文献   

15.
16.
Parallel to a zooplankton study (1999-2000) observations were made (from an inflatable boat), on the presence of dolphins along a transect (-8 km long) on the axis of Culebra Bay (24 km2), Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both years. The presence of S. attenuata in Culebra Bay might be associated to the abundances of fish and mollusks (their presumed prey: for example, squids), as evidenced by fishery statistics available for this zone of the Pacific coast of Costa Rica.  相似文献   

17.
Sullivan JB  Chacón I 《ZooKeys》2011,(149):39-49
So far, two species of Neotherina Dognin have been recorded in Costa Rica. Neotherina imperilla (Dognin) occurs primarily at altitudes between 1100 and 1700 meters and Neotherina callas (Druce) which is widely distributed above 1100 meters. A third, new species, Neotherina xanthosa Sullivan and Chacón is described from altitudes above 2400 meters. Heterogeneity of the genus is discussed.  相似文献   

18.
Three hundred and thirty two species of polychaetes belonging to 50 families are reported for Costa Rica based on previously published reports. In a few families, available material was re-examined and appropriate changes in species identifications were made. Only three species, (Glycera oxycephala Ehlers, 1887; Hemipodia pustulata (Friedrich 1956); and Scolepis (Scolepis) squamata (Miller, 1806)) have been reported from the Caribbean coast of Costa Rica, and these three species have also been reported from the Pacific Coast. The families with more than 15 species are the Spionidae (26), Cirratulidae (24), Nereididae (21), Lumbrineridae (19) and Paraonidae (16). Despite extensive sampling on the Pacific coast over the last 25 years, the Costa Rican polychaete fauna, especially that of the Caribbean coast, remains poorly known.  相似文献   

19.
As a result of a review of the Costaceae for theManual de las Plantas de Costa Rica, two new species ofCostus (C. ricus andC. osae) are here described and illustrated. The assignment of the new species ofCostus subgen.Costus is discussed.  相似文献   

20.
Keys in Spanish and English are given for the genera of Chrysomelinae known from Costa Rica. For each genus, a list of species compiled from collections in the University of Costa Rica, the National Biodiversity Institute, and the entomological literature is presented. The genus Planagetes Chevrolat 1843 is recorded for the first time from Central America, and the genus Leptinotarsa St?l 1858 is synonymized with Stilodes Chevrolat 1843.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号