scholarly journals Unprecedented ichneumonid parasitoid wasp diversity in tropical forests

2012 ◽  
Vol 279 (1748) ◽  
pp. 4694-4698 ◽  
Author(s):  
Anu Veijalainen ◽  
Niklas Wahlberg ◽  
Gavin R. Broad ◽  
Terry L. Erwin ◽  
John T. Longino ◽  
...  
Keyword(s):  
Species Richness ◽  
Dna Analysis ◽  
Morphological Characteristics ◽  
Parasitoid Wasp ◽  
Primary Data ◽  
Sampling Effort ◽  
Species Accumulation Curves ◽  
Additional Species ◽  
Diversity Gradient ◽  
Richness Patterns

The megadiverse parasitoid wasp family Ichneumonidae (Hymenoptera) is classically considered an exception to the extensively studied latitudinal diversity gradient: the majority of ichneumonid species are described from temperate regions. The gradient has been hypothesized to be dependent on the biology of the wasps, but recently questions of sampling and description biases have been raised. Here, we show with primary data that the species richness of Ichneumonidae is markedly underestimated in tropical areas and that latitudinal diversity patterns in the family remain uncharacterized. We discovered a startling 177 likely undescribed orthocentrine species with relatively low sampling effort in the forests of Central America and Amazonian Ecuador, over three times the previously known orthocentrine diversity in the world's tropics. Species accumulation curves reveal that we are just beginning to unveil the true extent of tropical orthocentrine diversity. We also found evidence for cryptic species; our DNA analysis revealed additional species not easily distinguishable using morphological characteristics. The difficulty in establishing species richness patterns of Ichneumonidae probably follows from the relative lack of taxonomic expertise and the low density of ichneumonid species throughout the landscape.

Watershed-level sampling effort requirements for determining riverine fish species composition

2005 ◽  
Vol 62 (7) ◽  
pp. 1580-1588 ◽  
Author(s):  
Katherine L Smith ◽  
Michael L Jones
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Fish Species ◽  
Correlation Coefficients ◽  
Sampling Effort ◽  
Species Accumulation Curves ◽  
Targeted Sampling ◽  
Weak Negative Correlation ◽  
Fish Species Composition ◽  
Riverine Fish

Accurate assessments of watershed-level species composition are necessary for comparative ecological studies, ecosystem health assessments, monitoring, and aquatic conservation prioritization. Several studies have addressed sampling effort requirements for characterizing fish species composition at a section of stream, but none have examined watershed-level requirements. In the spring and summer of 2002, we extensively sampled nine Great Lakes watersheds to assess sampling-effort requirements. Sampling requirements increased with the targeted percentage of estimated species richness. Sampling 15–119 randomly selected reaches of stream, stratified by stream order, was on average sufficient to detect 80%–100% of estimated species richness. Watershed size (km2) and estimated species richness each showed a weak, negative correlation with sampling-effort requirements in our study streams, with Pearson's correlation coefficients of –5.06 and –0.590, respectively. Because of among-watershed variability in sampling effort requirements, field crews should plot species accumulation curves onsite to determine adequate inventory completion. Based on the difficulty of detecting the last 10% of species, random sampling should be conducted in conjunction with targeted sampling of rare species.

scholarly journals Edge effects and landscape matrix use by a small mammal community in fragments of semideciduous submontane forest in Mato Grosso, Brazil

2008 ◽  
Vol 68 (4) ◽  
pp. 703-710 ◽  
Author(s):  
M. Santos-Filho ◽  
DJ. da Silva ◽  
TM. Sanaiotti
Keyword(s):  
Species Richness ◽  
Small Mammal ◽  
Species Number ◽  
Sampling Effort ◽  
Similar Species ◽  
Species Accumulation Curves ◽  
Mammal Species ◽  
Mato Grosso ◽  
Species Accumulation ◽  
Species Richness And Abundance

A community of small mammals was studied in seasonal semideciduous submontane forest in the state of Mato Grosso, Brazil. This study evaluated the use of edge and matrix pasture, by different small mammal species. Overall, 31 areas were studied, with a total sampling effort of 33,800 trap x nights. Only seven of the 25 species captured in the study sites were able to use the pasture matrix; we classified these species as generalists. Fourteen species were found to be intermediate in habits, being able to use forest edges. We found only four species habitat specialists, occurring only on transect lines in the interior of the fragment, at least 150 m from the edge. Transects located in the pasture matrix and 50 m from the edge had significantly lower species richness and abundance than transects located in the fragment edge or in the interior of the fragment. All transects located within the fragment had similar species richness and abundance, but transects located 50 m from the edge had slightly lower, but non-significant, species richness than transects located 100 m apart from edges. Rarefaction curves demonstrated that only medium-sized fragments (100 300 ha) reached an asymptote of species accumulation. The other areas require further sampling, or more sampling transect, before species accumulation curves stabilize, due to a continued increase in species number.

scholarly journals Variation in the diversity and richness of parasitoid wasps based on sampling effort

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4642 ◽  
Author(s):  
Thomas E. Saunders ◽  
Darren F. Ward
Keyword(s):  
Species Richness ◽  
Austral Summer ◽  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Sampling Effort ◽  
Summer Period ◽  
Wasp Species ◽  
The Cost ◽  
Number Of Individuals ◽  
The Relationship

Parasitoid wasps are a mega-diverse, ecologically dominant, but poorly studied component of global biodiversity. In order to maximise the efficiency and reduce the cost of their collection, the application of optimal sampling techniques is necessary. Two sites in Auckland, New Zealand were sampled intensively to determine the relationship between sampling effort and observed species richness of parasitoid wasps from the family Ichneumonidae. Twenty traps were deployed at each site at three different times over the austral summer period, resulting in a total sampling effort of 840 Malaise-trap-days. Rarefaction techniques and non-parametric estimators were used to predict species richness and to evaluate the variation and completeness of sampling. Despite an intensive Malaise-trapping regime over the summer period, no asymptote of species richness was reached. At best, sampling captured two-thirds of parasitoid wasp species present. The estimated total number of species present depended on the month of sampling and the statistical estimator used. Consequently, the use of fewer traps would have caught only a small proportion of all species (one trap 7–21%; two traps 13–32%), and many traps contributed little to the overall number of individuals caught. However, variation in the catch of individual Malaise traps was not explained by seasonal turnover of species, vegetation or environmental conditions surrounding the trap, or distance of traps to one another. Overall the results demonstrate that even with an intense sampling effort the community is incompletely sampled. The use of only a few traps and/or for very short periods severely limits the estimates of richness because (i) fewer individuals are caught leading to a greater number of singletons; and (ii) the considerable variation of individual traps means some traps will contribute few or no individuals. Understanding how sampling effort affects the richness and diversity of parasitoid wasps is a useful foundation for future studies.

scholarly journals Optimising Capture Methods for the Evaluation of Parasitoid Wasp Diversity

2018 ◽  
Author(s):  
Thomas Edward Saunders
Keyword(s):  
Species Richness ◽  
New Species ◽  
New Zealand ◽  
Parasitoid Wasp ◽  
Parasitoid Wasps ◽  
Sampling Effort ◽  
Optimal Sampling ◽  
Wasp Species ◽  
Use Of Resources ◽  
The Relationship

Parasitoid wasps are mega-diverse, ecologically dominant, but poorly studied components of global biodiversity. Despite their intensive application within pest management as biocontrol agents, little is known about native species. To understand their basic biology they must be collected in sampling programs. However, invertebrate surveys are increasingly subject to funding and time constraints that often preclude complete faunal inventories. In order to maximise the efficiency and reduce the cost of their collection, the application of optimal sampling techniques within a Rapid Biodiversity Assessment framework is proposed. Two sites in the Waitakere Ranges were sampled three times over the summer. An intensive sampling effort of 840 Malaise-trap-days over a three month period was used to determine the relationship between sampling effort and observed species richness. Rarefaction techniques and non-parametric estimators were used to predict true species richness and to evaluate the completeness of sampling. Results show that an intensive Malaise-trapping regime over the summer can capture two-thirds of parasitoid wasp species present. Sampling recommendations are provided to guide optimal usage of Malaise traps for both ecological studies and faunal inventories. Modern taxonomic methods are reviewed and a new species of parasitoid wasp is described, representing the first New Zealand species from the genus Lusius (Ichneumonidae: Ichneumoninae). Morphological measurements confirm the new species represents a significant range expansion for the genus. Greater collaboration between ecologists and taxonomists is encouraged, in order to make more efficient use of resources, data, and expertise unique to each discipline. This is the first study to investigate the relationship between sampling effort and parasitoid wasp diversity in New Zealand. It shows that very high sampling effort fails to catch all species present. Parasitoid wasps are known to be keystone species that show promise as indicators of environmental quality and as surrogates for the diversity of other taxa. The development of optimal sampling strategies will therefore provide an important foundation for their future study.

scholarly journals Enhancing georeferenced biodiversity inventories: automated information extraction from literature records reveal the gaps

2020 ◽  
Author(s):  
Bjørn Tore Kopperud ◽  
Scott Lidgard ◽  
Lee Hsiang Liow
Keyword(s):  
Information System ◽  
Species Richness ◽  
Language Processing ◽  
Concerted Effort ◽  
Location Data ◽  
Diversity Gradient ◽  
Biodiversity Inventories ◽  
Richness Patterns ◽  
First Time ◽  
Promising Avenue

AbstractWe use natural language processing (NLP) to retrieve location data for cheilostome bryozoan species (text-mined occurrences [TMO]) in an automated procedure. We compare these results with data from the Ocean Biogeographic Information System (OBIS). Using OBIS and TMO data separately and in combination, we present latitudinal species richness curves using standard estimators (Chao2 and the Jackknife) and range-through approaches. Our combined OBIS and TMO species richness curves quantitatively document a bimodal global latitudinal diversity gradient for cheilostomes for the first time, with peaks in the temperate zones. 79% of the georeferenced species we retrieved from TMO (N = 1780) and OBIS (N = 2453) are non-overlapping and underestimate known species richness, even in combination. Despite clear indications that global location data compiled for cheilostomes should be improved with concerted effort, our study supports the view that latitudinal species richness patterns deviate from the canonical LDG. Moreover, combining online biodiversity databases with automated information retrieval from the published literature is a promising avenue for expanding taxon-location datasets.

scholarly journals Truncated bimodal latitudinal diversity gradient in early Paleozoic phytoplankton

2021 ◽  
Vol 7 (15) ◽  
pp. eabd6709
Author(s):  
Axelle Zacaï ◽  
Claude Monnet ◽  
Alexandre Pohl ◽  
Grégory Beaugrand ◽  
Gary Mullins ◽  
...  
Keyword(s):  
Species Richness ◽  
Climate Changes ◽  
Sea Surface ◽  
Marine Phytoplankton ◽  
Sampling Effort ◽  
Early Paleozoic ◽  
Latitudinal Diversity Gradient ◽  
Diversity Gradient ◽  
Geological Past

The latitudinal diversity gradient (LDG)—the decline in species richness from the equator to the poles—is classically considered as the most pervasive macroecological pattern on Earth, but the timing of its establishment, its ubiquity in the geological past, and explanatory mechanisms remain uncertain. By combining empirical and modeling approaches, we show that the first representatives of marine phytoplankton exhibited an LDG from the beginning of the Cambrian, when most major phyla appeared. However, this LDG showed a single peak of diversity centered on the Southern Hemisphere, in contrast to the equatorial peak classically observed for most modern taxa. We find that this LDG most likely corresponds to a truncated bimodal gradient, which probably results from an uneven sediment preservation, smaller sampling effort, and/or lower initial diversity in the Northern Hemisphere. Variation of the documented LDG through time resulted primarily from fluctuations in annual sea-surface temperature and long-term climate changes.

scholarly journals The Effect of Climate and Human Pressures on Functional Diversity and Species Richness Patterns of Amphibians, Reptiles and Mammals in Europe

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 275
Author(s):  
Mariana A. Tsianou ◽  
Maria Lazarina ◽  
Danai-Eleni Michailidou ◽  
Aristi Andrikou-Charitidou ◽  
Stefanos P. Sgardelis ◽  
...  
Keyword(s):  
Species Richness ◽  
Functional Diversity ◽  
Agricultural Land ◽  
Influential Factor ◽  
Climatic Variables ◽  
Quadratic Entropy ◽  
Functional Richness ◽  
Precipitation Seasonality ◽  
Rao’S Quadratic Entropy ◽  
Richness Patterns

The ongoing biodiversity crisis reinforces the urgent need to unravel diversity patterns and the underlying processes shaping them. Although taxonomic diversity has been extensively studied and is considered the common currency, simultaneously conserving other facets of diversity (e.g., functional diversity) is critical to ensure ecosystem functioning and the provision of ecosystem services. Here, we explored the effect of key climatic factors (temperature, precipitation, temperature seasonality, and precipitation seasonality) and factors reflecting human pressures (agricultural land, urban land, land-cover diversity, and human population density) on the functional diversity (functional richness and Rao’s quadratic entropy) and species richness of amphibians (68 species), reptiles (107 species), and mammals (176 species) in Europe. We explored the relationship between different predictors and diversity metrics using generalized additive mixed model analysis, to capture non-linear relationships and to account for spatial autocorrelation. We found that at this broad continental spatial scale, climatic variables exerted a significant effect on the functional diversity and species richness of all taxa. On the other hand, variables reflecting human pressures contributed significantly in the models even though their explanatory power was lower compared to climatic variables. In most cases, functional richness and Rao’s quadratic entropy responded similarly to climate and human pressures. In conclusion, climate is the most influential factor in shaping both the functional diversity and species richness patterns of amphibians, reptiles, and mammals in Europe. However, incorporating factors reflecting human pressures complementary to climate could be conducive to us understanding the drivers of functional diversity and richness patterns.

scholarly journals Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

2004 ◽  
Vol 94 (2) ◽  
pp. 111-121 ◽  
Author(s):  
P.A.V. Borges ◽  
V.K. Brown
Keyword(s):  
Species Richness ◽  
Regional Scale ◽  
Local Scale ◽  
Local Species Richness ◽  
Β Diversity ◽  
Arthropod Species ◽  
Α Diversity ◽  
Local Species ◽  
Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

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