Biodiversity Data Journal :
Research Article
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Corresponding author: Leticia Bao (baoleticia@gmail.com)
Academic editor: Pedro Cardoso
Received: 12 Mar 2018 | Accepted: 24 Apr 2018 | Published: 03 May 2018
© 2018 Leticia Bao, Juaquín Ginella, Mónica Cadenazzi, Enrique Castiglioni, Sebastián Martínez, Luis Casales, María Caraballo, Álvaro Laborda, Miguel Simo
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Bao L, Ginella J, Cadenazzi M, Castiglioni EA, Martínez S, Casales L, Caraballo MP, Laborda Á, Simo M (2018) Spider assemblages associated with different crop stages of irrigated rice agroecosystems from eastern Uruguay. Biodiversity Data Journal 6: e24974. https://doi.org/10.3897/BDJ.6.e24974
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The rice crop and associated ecosystems constitute a rich mosaic of habitats that preserve a rich biological diversity. Spiders are an abundant and successful group of natural predators that are considered efficient in the biocontrol of the major insect pests in agroecosystems. Spider diversity in different stages of the rice crop growth from eastern Uruguay was analysed. Field study was developed on six rice farms with rotation system with pasture, installed during intercropping stage as cover crop. Six rice crops distributed in three locations were sampled with pitfall and entomological vaccum suction machine. Sixteen families, representing six guilds, were collected. Lycosidae, Linyphiidae, Anyphaenidae and Tetragnathidae were the most abundant families (26%, 25%, 20% and 12%, respectively) and comprised more than 80% of total abundance. Other hunters (29%), sheet web weavers (25%) and ground hunters (24%) were the most abundant guilds. Species composition along different crop stages was significantly different according to the ANOSIM test. The results showed higher spider abundance and diversity along the crop and intercrop stages. This study represents the first contribution to the knowledge of spider diversity associated with rice agroecosystem in the country.
Agroecology, Araneae, diversity, guilds composition, rice crop
The study of biological diversity associated with agroecosystems has focused the attention of biologists in the last decades to produce sustainable crops. One of them has been the cultivation of rice, which is the most ancient form of intensive agriculture in the world (
Uruguay produced 1,348,301 tonnes of rice, becoming the seventh exporter country inthe world during the 2013/2014 season (
The rice crop and associated ecosystems (natural environments or other crops) constitute a rich mosaic of habitats that preserve a high biological diversity (
A few studies related to spider diversity in agroecosystems and adjacent environments have been carried out in Uruguay (
In the present paper, we study the spider diversity in different stages of the rice crop from eastern Uruguay, with the aim of identifying the changes along the crop cycle and to provide baseline information as a tool for evaluation of the impact of management practices on crop sustainability.
Study area and crop management
The main area for rice production in Uruguay is located in the eastern region of the country (
Spider collection and data analysis
From November 2013 to November 2015, two rice paddies on each of the three collecting sites were sampled seasonally (one rice paddy of first and other of second year), resulting in six rice paddies in the whole work. Spiders were sampled with pitfall traps and an entomological vacuum suction machine. Fifteen pitfall traps were installed for each crop and set for a week. Each trap consisted of a 400 ml cup containing 100 ml conservative mix (8.5 volumes of distilled water, 1.5 volumes of acetic acid 4%, 1 volume NaCl). Ground and vegetation from the surrounded area of each pitfall trap (3 to 4 metres away) was sampled during one minute with the vacuum suction machine (fifteen samples per paddy). The collected material was kept in 70% ethanol. Specimens were identified at family and species/morphospecies level using keys and taxonomic revisions from literature (
A total of 16 families, 61 species/morphospecies and six guilds of spiders were registered (Table
Family |
Species/morphospecies |
Anyphaenidae |
Acanthoceto acupicta |
Arachosia magna |
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Sanogasta maculatipes |
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Araneidae |
Alpaida veniliae |
Alpaida versicolor |
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Argiope argentata |
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Araneidae sp1 |
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Larinia bivittata |
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Corinnidae |
Mazax cf ramirezi |
Ctenidae |
Asthenoctenus borellii |
Gnaphosidae |
Camilina chilensis |
Apopyllus silvestri |
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Gnaphosidae sp1 |
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Linyphiidae |
Linyphiidae sp1 to sp9 |
Scolecura propinqua |
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Sphecozone ignigena |
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Sphecozone sp1 |
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Sphecozone sp2 |
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Tutaibo sp1 |
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Tutaibo sp2 |
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Lycosidae |
Agalenocosa velox |
Allocosa sp1 |
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Allocosa sp2 |
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Allocosa sp3 |
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Diapontia uruguayensis |
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Lobizon corondaensis |
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Lobizon humilis |
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Lycosa cf thorelli |
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Lycosa u-album |
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Lycosinae sp1 |
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Lycosinae sp2 |
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Lycosa auroguttata |
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Schizocosa malitiosa |
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Miturgidae |
Miturgidae sp1 |
Oxyopidae |
Oxyopes salticus |
Pholcidae |
Pholcidae sp1 |
Salticidae |
Hisukattus transversalis |
Dendryphantes mordax |
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Salticidae sp1 |
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Salticidae sp2 |
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Salticidae sp3 |
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Tetragnathidae |
Glenognatha lacteovitatta |
Leucage volupis |
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Tetragnatha sp1 |
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Tetragnatha sp2 |
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Theridiidae |
Steatoda ancorata |
Theridiidae sp1 |
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Theridiidae sp2 |
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Thymoites sp1 |
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Thomisidae |
Thomisidae sp1 |
Thomisidae sp2 |
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Titanoecidae |
Goeldia luteipes |
Trachelidae |
Meriola cetiformis |
Family | Sampling moment | ||||||||
post-seeding | tillering 1 | grain filling 1 | intercrop 1 | tillering 2 | grain filling 2 | intercrop 2 | Subtotal | % | |
Anyphaenidae | 25 | 116 | 144 | 6 | 24 | 67 | 33 | 415 | 19.88 |
Araneidae | 0 | 6 | 12 | 30 | 7 | 12 | 9 | 76 | 3.64 |
Corinnidae | 2 | 0 | 0 | 0 | 1 | 0 | 2 | 5 | 0.24 |
Ctenidae | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0.05 |
Gnaphosidae | 3 | 1 | 0 | 0 | 1 | 0 | 0 | 5 | 0.24 |
Linyphiidae | 100 | 129 | 26 | 91 | 37 | 11 | 122 | 516 | 24.71 |
Lycosidae | 30 | 197 | 53 | 32 | 65 | 59 | 114 | 550 | 26.34 |
Miturgidae | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 3 | 0.14 |
Oxyopidae | 0 | 4 | 1 | 1 | 1 | 1 | 24 | 32 | 1.53 |
Pholcidae | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0.05 |
Salticidae | 9 | 35 | 49 | 2 | 4 | 11 | 25 | 135 | 6.47 |
Tetragnathidae | 23 | 106 | 24 | 18 | 25 | 39 | 10 | 245 | 11.73 |
Theridiidae | 2 | 8 | 16 | 9 | 4 | 1 | 11 | 51 | 2.44 |
Thomisidae | 2 | 3 | 1 | 4 | 0 | 26 | 7 | 43 | 2.06 |
Titanoecidae | 1 | 0 | 0 | 0 | 3 | 0 | 0 | 4 | 0.19 |
Trachelidae | 0 | 0 | 1 | 0 | 1 | 2 | 2 | 6 | 0.29 |
198 | 606 | 330 | 193 | 173 | 229 | 359 | 2088 | 100 |
Hisukattus transversalis Galiano, 1987, Lycosa auroguttata (Keyserling, 1891), Lobizon corondaensis (Mello-Leitão, 1941), Agalenocosa velox (Keyserling, 1891), Sphecozone ignigena (Keyserling, 1886), Camillina chilensis (Simon, 1902), Mazax ramirezi (Rubio & Danişman, 2014) and Arachosia magna are registered for the first time for Uruguay (Table
Spider abundance adjusted to Poisson distribution and presented statistical differences between sampling periods, showing higher values in the intercrop stages and the lower values immediately after seeding (F= 24.22, df=562 p>0.0001, Fig.
A) Mean number of spiders per sample. Different letters indicate significant differences compared by Tukey-Kramer test (F=24.22, df=562, p<0.0001). B) Mean spider species richness. Different letters indicate significant differences compared by Tukey_Kramer test (F=7.16, df=6, p<0.0036). Sampling periods: 1:post-seeding,; 2 and 5: tillering, 3 and 6: grain filling; 4 and 7: intercrop.
Other hunters, sheet web weavers and ground hunters were the more abundant guilds with 29%, 25% and 24% of relative abundance respectively (Fig.
Species accumulation curve was non-asymptotic, indicating that there could be additional species to be sampled (Fig.
Species accumulation curves of observed (S) and corrected richness (S est: 500 randomisations), singletons, doubletons, uniques and duplicates from the forty samples from different sampling moments: 1-6: post-seeding, 7-12, 23-28: tillering, 13-18, 29-34: grain filling, 19-22, 35-40: intercrop.
According to the SIMPER test comparing between collecting moments, Lycosa thorelli (Keyserling, 1877), Glenognatha lacteovitatta (Mello-Leitao, 1944), Scolecura propinqua (Millidge, 1991), Tetragnatha sp. 1, Diapontia uruguayensis (Keyserling, 1877), Sphecozone ignigena (Keyserling, 1886) and Sanogasta maculatipes (Keyserling, 1891) contributed to 57% of the observed dissimilarity (Suppl. material
Total number of spiders per sample was lower in the early crop stages and increasing to the end of the crop cycle. Recently tilled fields had low vegetation complexity and represent a critical period for predator’s establishment (
In this study, we confirm that rice crops serve as reservoirs for spider species that where recorded at different regional environments.
A. magna was reported in grasses and near streams from Argentina (
A. velox was registered in flooded grasslands from Argentina (
L. corondaensis was reported for woodlands neighbouring grasslands from Argentina (
Mazax ramirezi was collected in pitfall traps for grasslands from Buenos Aires, Argentina. In this study, all the exemplars were also obtained with this type of traps and the species was found throughout the rice cycle.
Lobizon humilis (Mello-Leitao, 1944) (Lycosidae) was registered mainly during the intercrop stage. The species was reported from Argentina (
Sanogasta maculatipes (Anyphaenidae) was more abundant at tillering and grain filling stages in the rice cultivation, as it was also reported from Brazilian crops (
Glenognatha lacteovitatta (Tetragnathidae) was reported for alfalfa and wheat crops from Argentina (
The family Linyphiidae presented high species diversity and it was the second more abundant in this study. This result agrees with the results of
The range percentage obtained for the richness estimators was nearly 70% to 87%, indicating that a comprehensive inventory would be reached (
Except for sensing web spiders, all the guilds proposed by
This study represents the first contribution to the knowledge of spider diversity associated with rice crop agroecosystems in Uruguay. The results showed a high spider abundance and diversity throughout the crop and intercrop stages. Future research should focus on successional changes in the mosaic of landscapes of the region and evaluate the effects of management strategies on biodiversity, in order to promote its conservation and assure a sustainable rice crop production through natural biological control.
To Héctor Da Fonseca, Jorge and Raúl Servetto, who kindly allowed us to conduct the research on their farms; and to Ing. Agr. Marcelo Segovia for his help on Charqueada farm selection and providing farm management information.
Fellowship ANII POSNAC_2012_4459 L. Bao.
Unidad de Entomología. Facultad de Agronomía. Universidad de la República. Garzón 780. CP 12900. Montevideo. Uruguay.
The paper was originally conceived by LB and MS. The study was designed by LB, MC and EC, LB, LC, SM and MPC carried out the field work. MS, LB, JG and AL identified the exemplars and performed the curatorial work. LB, MS and MC analyzed the data. LB and MS wrote the final version of the manuscript. All authors read and approved the final manuscript
Dissimilarity Matrix of SIMPER Test obtained with PAST 3.14 software (Hammer et al. 2001).