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

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.

2018 ◽  
Author(s):  
Thomas Edward Saunders

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.


2006 ◽  
Vol 22 (2) ◽  
pp. 167-176 ◽  
Author(s):  
Ilari E. Sääksjärvi ◽  
Kalle Ruokolainen ◽  
Hanna Tuomisto ◽  
Samuli Haataja ◽  
Paul V. A. Fine ◽  
...  

Local species richness and between-site similarity in species composition of parasitoid wasps (Hymenoptera: Ichneumonidae; Pimplinae and Rhyssinae) were correlated with those of four plant groups (pteridophytes, Melastomataceae, Burseraceae and Arecaceae) in a western Amazonian lowland rain forest mosaic. The mosaic structure of the forest was related to variation in soils within the non-inundated terrain. Significant matrix correlation between patterns in parasitoid wasp species composition and plant species composition was found. Most of the overall correlation was due to idiobiont parasitoids of weakly concealed hosts, which attack host larvae and pupae in exposed situations, with two of the four ecologically defined parasitoid groups showing no correlation at all. A positive correlation between the number of plant species and the number of Pimplinae and Rhyssinae species at a site was found when the latter was corrected for collecting effort. Consequently, the degree of floristic difference between sites may be indicative of the difference in species composition of ichneumonids, and the species richness of plants may serve as a predictor of the species richness of parasitoid wasps. Although these results were obtained in a mosaic including structurally and floristically clearly different types of rain forest, the correlation coefficients were relatively low, and the present results lend only weak support to the idea of using plant distributions as indicators of animal distributions.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shimaa A. M. Ebrahim ◽  
Gaëlle J. S. Talross ◽  
John R. Carlson

AbstractParasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression.


2012 ◽  
Vol 6 (4) ◽  
pp. 530-536 ◽  
Author(s):  
Josephine J. Rodriguez ◽  
Jose L. Fernández-Triana ◽  
M. Alex Smith ◽  
Daniel H. Janzen ◽  
Winnie Hallwachs ◽  
...  

2005 ◽  
Vol 137 (1) ◽  
pp. 120-127 ◽  
Author(s):  
Christopher M. Buddle ◽  
Julien Beguin ◽  
Elise Bolduc ◽  
Alida Mercado ◽  
Tara E. Sackett ◽  
...  

AbstractFor over three decades, the importance of taxon sampling curves for comparative biodiversity studies has been repeatedly stated. However, many entomologists (both within Canada and worldwide) continue to publish studies without standardizing their data to take sampling effort into account. We present a case study to illustrate the importance of such standardization, using the collection of spiders (Araneae) by pitfall traps as model data. Data were analyzed using rarefaction to represent one example of a taxon sampling curve, and by a variety of traditional diversity indices to describe alpha diversity. Raw species richness and single-index diversity measures (Shannon–Wiener, Simpson's, and Fisher's α) provided contradictory results. Rarefied species richness standardized to the number of individuals collected enabled more accurate comparisons of diversity and revealed when sampling was insufficient. Focusing on arthropods occurring in forested ecosystems, we also examined the use of taxon sampling curves in current literature by reviewing 133 published articles from 14 journals. Only 26% of the published articles in our review used a taxon sampling curve, and raw species richness and the Shannon–Wiener index of diversity were the most commonly used estimates. There is clearly a need to modify how alpha diversity is measured and compared for arthropod biodiversity studies. We recommend the abandonment of both raw species richness and single-index measures of diversity, and reiterate the need to use rarefaction or a related technique that allows for meaningful comparisons of species richness while taking into account sampling effort.


2019 ◽  
Vol 6 (8) ◽  
pp. 190913 ◽  
Author(s):  
Tapani Hopkins ◽  
Heikki Roininen ◽  
Ilari E. Sääksjärvi

Tropical invertebrates, such as the ichneumonids of tropical forests, are poorly known. Here, we report the first results of extensive sampling at Kibale National Park, Uganda, by providing some of the first tropical ecological data for the ichneumonid subfamily Rhyssinae. We sampled ichneumonids with 34 Malaise traps for a year in 10 sites, in habitats ranging from primary forest to farmland. We also gathered weather and vegetation data. The total sampling effort was 373 trap months and we caught 444 rhyssines in six species. We caught the most rhyssines in dry weather, and towards the end of the sampling year. The rhyssines showed a clear preference for decaying logs and for primary forest. We fitted a model which can be used to predict future catches at the site, and draw conclusions on when rhyssines emerge and on their adult lifespan. Sampling extensively gave us a wealth of ecological data on a poorly known parasitoid wasp subfamily. We recommend that future tropical sampling collect ecological data, and that existing data from previous large-scale surveys be used for ecological analyses.


2012 ◽  
Vol 279 (1748) ◽  
pp. 4694-4698 ◽  
Author(s):  
Anu Veijalainen ◽  
Niklas Wahlberg ◽  
Gavin R. Broad ◽  
Terry L. Erwin ◽  
John T. Longino ◽  
...  

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.


2022 ◽  
Author(s):  
Meng Mao ◽  
Michael R. Strand ◽  
Gaelen R. Burke

Bracoviruses (BVs) are endogenized nudiviruses in parasitoid wasps of the microgastroid complex (family Braconidae). Microgastroid wasps have coopted nudivirus genes to produce replication-defective virions that females use to transfer virulence genes to parasitized hosts. The microgastroid complex further consists of six subfamilies and ∼50,000 species but current understanding of BV gene inventories and organization primarily derives from analysis of two wasp species in the subfamily Microgastrinae ( Microplitis demolitor and Cotesia congregata ) that produce M. demolitor BV (MdBV) and C. congregata BV (CcBV). Notably, several genomic features of MdBV and CcBV remain conserved since divergence of M. demolitor and C. congregata ∼53 million years ago (MYA). However, it is unknown whether these conserved traits more broadly reflect BV evolution, because no complete genomes exist for any microgastroid wasps outside of the Microgastrinae. In this regard, the subfamily Cheloninae is of greatest interest because it diverged earliest from the Microgastrinae (∼85 MYA) after endogenization of the nudivirus ancestor. Here, we present the complete genome of Chelonus insularis , which is an egg-larval parasitoid in the Cheloninae that produces C. insularis BV (CinsBV). We report that the inventory of nudivirus genes in C. insularis is conserved but are dissimilarly organized when compared to M. demolitor and C. congregata . Reciprocally, CinsBV proviral segments share organizational features with MdBV and CcBV but virulence gene inventories exhibit almost no overlap. Altogether, our results point to the functional importance of a conserved inventory of nudivirus genes and a dynamic set of virulence genes for the successful parasitism of hosts. Our results also suggest organizational features previously identified in MdBV and CcBV are likely not essential for BV virion formation. Significance Bracoviruses are a remarkable example of virus endogenization, because large sets of genes from a nudivirus ancestor continue to produce virions that thousands of wasp species rely upon to parasitize hosts. Understanding how these genes interact and have been coopted by wasps for novel functions is of broad interest in the study of virus evolution. This manuscript characterizes bracovirus genome components in the parasitoid wasp Chelonus insularis , which together with existing wasp genomes captures a large portion of the diversity among wasp species that produce bracoviruses. Results provide new information about how bracovirus genome components are organized in different wasps while also providing additional insights on key features required for function.


2020 ◽  
Author(s):  
Shimaa Ebrahim ◽  
Gaëlle Talross ◽  
John R. Carlson

Abstract Parasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species, and many such wasps are used globally to control insect pests. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. However, the nature of these responses and the mechanisms that underlie them await further exploration. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation in a genetic model system for further exploration of how the activation of visual circuits by the sight of a parasitoid wasp alters both sexual behavior and gene expression.


2022 ◽  
Vol 9 ◽  
Author(s):  
Bracha Schindler ◽  
Efrat Gavish-Regev ◽  
Tamar Keasar

In order to integrate parasitoid wasps in agroecosystems as biological control agents, we need to understand how insecticides affect the parasitoids in the crops and their surroundings. We investigated the non-target effect of Indoxacarb, an insecticide commonly used against European grapevine moth, on parasitoid wasp communities in vineyards. We focused on characterizing: 1. The dynamics of common wasp species, and 2. Wasp abundance and species richness in the vineyard center, edge, and nearby natural area. Seven vineyards, with neighboring natural areas, were sampled before, and up to 2 weeks after, Indoxacarb applications over 2 years. We expected initial negative effects of spraying in the vineyard with some effect of Indoxacarb drift into the natural habitat, followed by wasp recovery, first in natural areas, then at the vineyard edge and finally in the center. Sticky traps were hung at the vineyard edge and center to evaluate migration into and out of the vineyard. Vacuum sampling was used to obtain parasitoid total abundance and species richness, and the abundances of four common species (43% of the wasps collected). From the vacuum samples we found that total wasp abundance and richness declined after spraying in the vineyards’ margins and center but rose over time in the natural area. Vineyard wasp abundance was restored to pre-spraying levels within 2 weeks. Among the abundant species, Trichogramma sp. and Telenomus sp., which parasitize lepidopteran hosts, declined after spraying, and Trichogramma sp. recovered more quickly than Telenomus sp. Two other abundant species, Lymaenon litoralis and Oligosita sp., did not decline after spraying. In the sticky traps, wasp abundance increased at the vineyard edge but not center after spraying, suggesting that there was migration of wasps at the vineyard edge, into or out of the crop. The results indicate an effect of Indoxacarb on the parasitoid wasp community, particularly on parasitoids of lepidopterans, the target group of Indoxacarb. The results also indicate a potential for recovery of the parasitoid community through migration from neighboring natural vegetation.


Sign in / Sign up

Export Citation Format

Share Document