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1.
Nat Ecol Evol ; 4(1): 40-45, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31844189

RESUMO

According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously supports the primacy of competition and the persistence of rare species. Abundant species monopolize negative associations in about 90% of the assemblages. On the other hand, rare species are mostly involved in positive associations, forming small network modules. Simulations suggest that positive interactions among rare species and microhabitat preferences are the most probable mechanisms underpinning this pattern and rare species persistence. The consistent results across taxa and geography suggest a general explanation for the maintenance of biodiversity in competitive environments.

2.
Zootaxa ; 4623(3): zootaxa.4623.3.6, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31716250

RESUMO

We describe a new species of Pachyphloea from the Natural National Park (NNP) Chicaque, Cundinamarca in the Colombian Andes, providing data on the structure and variability of its eggs. In addition, we synonymize Grylloclonia n. syn. under Pachyphloea, and provide a key for distinguishing males and females of the known species. Finally, we discuss the taxonomical delimitation of genera within the tribe Xerosomatini, and highlight the necessity of carrying out additional studies in this particular taxon of stick insects.


Assuntos
Insetos , Neópteros , Animais , Feminino , Masculino
3.
Environ Entomol ; 47(6): 1376-1387, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30192974

RESUMO

The study of diversity gradients is a frequent approach to understand evolutionary processes that structure communities. Altitudinal gradients allow the analysis of community spatial responses to environmental fluctuations. One interesting place to study altitudinal gradients is the Andes system because of the coexistence of isolated and continuous mountain ranges. We investigated the altitudinal turnover of species in peripheral mountainous systems by analyzing the structure of dung beetle assemblages along a complete gradient in the Sierra Nevada de Santa Marta, Colombia. Seven sites ranging from 480 to 2,890 m were evaluated, using linear transects of pitfall traps. A total of 2,992 individuals and 46 species were collected. Abundance, richness, and diversity diminished with altitude, revealing significant differences among sites. Some genera appeared at certain altitudes and most species appeared at unique sites, indicating a marked altitudinal turnover. A similarity analysis demonstrated the existence of separate lowland and high mountain groups with a turnover at 1,200-1,600 m asl. We registered for the first time a species replacement between Scarabaeinae (low-lands) and Aphodiinae (high-lands) in the Neotropical region. Our results largely agree with the species pattern described for Mesoamerica, although, in this case the altitudinal turnover is more evident, unveiling a transition zone between lowland and high mountain fauna elements. This result suggests an equilibrium between a weak horizontal colonization and a strong vertical turnover, that appears to be higher in isolated mountains. Future investigations with other insect groups are necessary to corroborate this altitudinal pattern in isolated mountains.


Assuntos
Altitude , Besouros , Ecossistema , Animais , Colômbia
4.
Rev Biol Trop ; 63(1): 97-125, 2015 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-26299118

RESUMO

The promotion of biodiversity conservation strategies must address the lack of information and the difficulty of identifying knowledge gaps that may facilitate our knowledge of different taxonomic groups. Dung beetles constitute one of those groups, despite having been proposed as an efficient bioindicator of environmental disturbance processes. In this work, we aimed to prepare a diagnosis on the state of knowledge of the subfamily Scarabaeinae, focusing on the cover sampling degree of this group in Colombia, with the purpose of identifying high-priority areas that will allow the completion of a national inventory. The work consisted of a bibliographical compilation using 12 referential databases and the examination of specimens deposited in 26 national collections. A total of 16 940 individuals were examined, finding registers for 232 species from 386 localities. The respective distribution cover maps were presented, and the cover at a national level was 10.62%. A historical analysis demonstrated a proliferation in the number of studies for the last three decades; nevertheless, a great proportion of unpublished works persists, resulting in only 64 sampled localities with published records. The localities with the greatest sampling efforts were RN La Planada, Lloro, AUN Los Estoraques, PNN Tinigua and Mariquita. Registries for all departments were available, and the best sampled ones were Cundinamarca, Antioquia, Valle del Cauca and Boyaca. The ecosystems with the greatest number of publications are the Andean pre mountain humid forest, followed by the Andean mountain humid forest and the Pacific humid forest. Other ecosystems with few studies included mangroves, desert zones, natural savannahs, palm swamps, paramos, flooding forests and agroforestry systems. The biogeographic region with the greatest number of localities was the Andean region, followed by Choco-Magdalenense and Amazonia. Our results showed that high levels of subsampling persist and that some zones lack registries, as in the case of some parks of the national system of protected areas. It is imperative that the sampling cover is extended at a national level, focusing all possible efforts on collecting in those subsampled regions that have high conservation importance, with the main goal of completing the listing of species and their distribution.


Assuntos
Biodiversidade , Besouros/classificação , Animais , Colômbia , Densidade Demográfica
5.
Zootaxa ; 3941(1): 104-16, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25947496

RESUMO

We describe six new species of crickets from the subfamily Podoscirtinae in the family Gryllidae from the "Amacayacu" National Park: Diatrypa (Latispeculum) didieri n. sp. (Aphonoidini: Diatrypina), Ectotrypa brachyptera n. sp. (Paroecanthini: Paroecanthina), Aphonomorphus (Aphonomorphus) desutterae n. sp., Aphonomorphus (Euaphonus) andreae n. sp., Aphonomorphus (Euaphonus) gorochovi n. sp., and Aphonomorphus (Nigraphonus) otavoi n. sp. (Podoscirtini: Aphonomorphina). Nigraphonus n. subgen. is proposed as a new subgenus of Aphonomorphus, grouping the species with unclear position into Neoaphonus (A. obscurus Chopard, 1956 n. comb., A. parobscurus Gorochov, 2010 n. comb., and A. nigra n. sp.). The state of knowledge of Podoscirtinae in Colombia is discussed.


Assuntos
Gryllidae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Colômbia , Feminino , Gryllidae/anatomia & histologia , Gryllidae/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Parques Recreativos
6.
Zootaxa ; 3826(2): 315-28, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24990049

RESUMO

The family Osmylidae is recorded for the first time in Colombia, extending its known distribution range to the north of South America in the northern Andes. Two new species of the genus Isostenosmylus Krüger, 1913, I. contrerasi n. sp. and I. septemtrionalandinus n. sp. and one morphospecies distributed along the eastern cordillera in the departments of Cundinamarca, Huila, and Norte de Santander are described and illustrated. A key to species of the genus Isostenosmylus, as well as a list of South American species of Osmylidae is included.


Assuntos
Insetos/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Colômbia , Feminino , Insetos/classificação , Masculino
7.
Rev Biol Trop ; 61(2): 735-52, 2013 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23885586

RESUMO

Abstract: Scarabaeoidea superfamily (Insecta: Coleoptera) as a bioindicator element of anthropogenic disturbance in an amazon national park. Insects have been recognized to be important indicators of the quality elements of ecosystems, among others, because of their rapid response to environmental variability and ease cost-effective capture. In this work we evaluated whether beetles of the Scarabaeoidea superfamily may be used as bioindicators of anthropogenic disturbance of Amazonian terra firme rain forests, in order to provide guidelines for monitoring strategies of the Amacayacu National Park. We considered three different levels of anthropogenic disturbance (i.e. low, medium, high) in 12 transects (four in each intervention level), and caught all beetle species of this superfamily. Three interception traps, two light traps, three pitfalls and four bottle fruit traps were used per transect, as well as manual catch. In total, 593 individuals belonging to 92 species, 44 genera and seven families were collected. Scarabaeidae (n = 232, 27 spp.) and Dynastidae (n = 161, 26 spp.) were the families with the highest number of individuals and species, while Aphodiidae, Cetoniidae and Geotrupidae exhibited the lowest. The most abundant species per family were Ateuchus sp. (33.2%) from Scarabaeidae, Cyclocephala verticalis (55.9%) from Dynastidae, Astaena sp. (75.8%) from Melolonthidae, Ceratocanthus amazonicus (66.7%) from Ceratocanthidae y Chaetodus asuai (96.8%) from Hybosoridae. Results showed that the number of species and individuals increased with the anthropogenic disturbance. The Margalef and Shannon indexes also revealed that the highest richness and equity occurred in the high-disturbed site, respectively. Dynastidae exhibited the highest number of exclusive species per gradient, while Scarabaeidae shared most of its species. Ten species were recorded in the three disturbance levels, 26 species in two and 56 species were exclusive to one level. The most abundant species Chaetodus asuai (Hybosoridae) presented a significant decrease in the number of individuals as disturbance increased, while an inverse relationship occurred for C verticalis (Dynastidae). For Astaena sp. (Melolonthidae) and Ligyrus gyas (Dynastidae) a high number of individuals was recorded and were exclusive for one forest site (low and high disturbed forest, respectively). The complete superfamily cannot be used like a single bioindicator element because it displays, in a specific level, very different behaviors in each disturbance condition. We discuss the use of richness and diversity as indicators of disturbance, while we highlight abundance of particular taxa as a better metric for disturbance.


Assuntos
Biodiversidade , Biomassa , Besouros/classificação , Conservação dos Recursos Naturais , Monitoramento Ambiental/métodos , Animais , Colômbia , Densidade Demográfica
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