Aquatic Insects and Benthic Diatoms: A History of Biotic Relationships in Freshwater Ecosystems

The most important environmental characteristic in streams is flow. Due to the force of water current, most ecological processes and taxonomic richness in streams mainly occur in the riverbed. Benthic algae (mainly diatoms) and benthic macroinvertebrates (mainly aquatic insects) are among the most important groups in running water biodiversity, but relatively few studies have investigated their complex relationships. Here, we review the multifaceted interactions between these two important groups of lotic organisms. As the consumption of benthic algae, especially diatoms, was one of the earliest and most common trophic habits among aquatic insects, they then had to adapt to the particular habitat occupied by the algae. The environmental needs of diatoms have morphologically and behaviorally shaped their scrapers, leading to impressive evolutionary convergences between even very distant groups. Other less evident interactions are represented by the importance of insects, both in preimaginal and adult stages, in diatom dispersion. In addition, the top-down control of diatoms by their grazers contributes to their spatial organization and functional composition within the periphyton. Indeed, relationships between aquatic insects and diatoms are an important topic of study, scarcely investigated, the onset of which, hundreds of millions of years ago, has profoundly influenced the evolution of stream biological communities.FESR, Interreg Alcotra 2014-2020, EcO Project of the Piter Terres Monvis

The InBIO Barcoding Initiative Database: contribution to the knowledge on DNA barcodes of Iberian Plecoptera

Background The use of DNA barcoding allows unprecedented advances in biodiversity assessments and monitoring schemes of freshwater ecosystems; nevertheless, it requires the construction of comprehensive reference collections of DNA sequences that represent the existing biodiversity. Plecoptera are considered particularly good ecological indicators and one of the most endangered groups of insects, but very limited information on their DNA barcodes is available in public databases. Currently, less than 50% of the Iberian species are represented in BOLD. New information The InBIO Barcoding Initiative Database: contribution to the knowledge on DNA barcodes of Iberian Plecoptera dataset contains records of 71 specimens of Plecoptera. All specimens have been morphologically identified to species level and belong to 29 species in total. This dataset contributes to the knowledge on the DNA barcodes and distribution of Plecoptera from the Iberian Peninsula and it is one of the IBI database public releases that makes available genetic and distribution data for a series of taxa. The species represented in this dataset correspond to an addition to public databases of 17 species and 21 BINs. Fifty-eight specimens were collected in Portugal and 18 in Spain during the period of 2004 to 2018. All specimens are deposited in the IBI collection at CIBIO, Research Center in Biodiversity and Genetic Resources and their DNA barcodes are publicly available in the Barcode of Life Data System (BOLD) online database. The distribution dataset can be freely accessed through the Global Biodiversity Information Facility (GBIF).European Union (EU) 668981Operational Thematic Program for Competitiveness and Internationalization (POCI), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) POCI-01-0145-FEDER-022127EDP Biodiversity ChairLong Term Research Site of Baixo Sabor LTER_EU_PT_002Portuguese Foundation for Science and Technology SFRH/BD/104703/2014 SFRH/BD/133159/201

Wintering avifauna of Chaco and pantanal habitats in Bahí­a Negra (Northern Paraguay)

Se estudió la avifauna de hábitats típicos de dos ecorregiones, el Pantanal y el Chaco, en el norte de Paraguay (departamento de Alto Paraguay) mediante transectas y observaciones puntuales. Se detectaron 132 especies (109 en bosque y 75 en río), de las cuales 37 utilizaban además hábitats modificados. Las especies más abundantes fueron <i>Phalacrocorax olivaceus</i>, <i>Pitangus sulphuratus</i> y <i>Gnorimopsar chopi</i> en el río y <i>Agelaioides badius</i>, <i>Coryphospingus cucullatus</i> y <i>Sicalis luteola</i> en el bosque. Doce especies en el río y 11 en el bosque aparecieron en el 100% de los recorridos de las transectas, siendo 5 de ellas comunes a ambas zonas. Siete especies (6.4%) del bosque tuvieron un tamaño promedio de grupo de cinco o más individuos, mientras que en el río fueron seis (8%). En el bosque eran numerosas las bandadas mixtas de <i>Zonotrichia capensis</i>, <i>Sicalis luteola</i>, <i>Coryphospingus cucullatus</i>, <i>Paroaria coronata</i>, <i>Agelaioides badius</i> y <i>Molothrus bonariensis</i>. La diversidad de especies observada fue de 80.4 en el bosque y de 58.1 en el río.The avifauna of habitats typical of two ecoregions in northern Paraguay (Alto Paraguay Department), Chaco and Pantanal, was studied through transects and opportunistic observations. Of 132 species recorded, 109 were in the forest, 75 in the river, and 37 in disturbed habitats. The most common species were <i>Phalacrocorax olivaceus, Pitangus sulphuratus</i> and <i>Gnorimopsar chopi</i> in the river, and <i>Agelaioides badius, Coryphospingus cucullatus</i> and <i>Sicalis luteola</i> in the forest. Twelve species of river habitats and 11 species of forest habitats were recorded in all samplings, five of them common to both zones. Seven species (6.4%) of the forest and six (8%) of the river averaged a flock size of five or more individuals. In the forest, flocks were numerous and composed primarily of <i>Zonotrichia capensis, Sicalis luteola, Coryphospingus cucullatus, Paroaria coronata, Agelaioides badius</i> and <i>Molothrus bonariensis</i>. Species diversity was 80.4 in the forest and 58.1 in the river

Do Neotropical adult dobsonflies (Megaloptera, Corydalidae) feed on solid material in the nature? Information from a gut content study

Females of two species of corydalids (Megaloptera), Corydalus magnus Contreras-Ramos, 1998 and Platyneuromus soror (Hagen, 1861), are studied with the aim to determine if solid food is present in their guts, which would indicate the existence of feeding on solid food during the imaginal life in nature. Gut anatomical architecture is also studied and described for females of both species, showing no peculiarities regarding the existing information in other close related species and confirming that digestive morphology is conserved in Megaloptera, as previously reported in literature. No significant solid food was detected in any of the species, so in the nature, they may rely more on liquid sources and/or fat reserves produced in the larval stage for the energetic requirements of adult life

The First Study of Mating Mistakes in Stoneflies (Plecoptera) from China, with Remarks on Their Biological Implications

Currently, information on the biology of Plecoptera from China is scarce, particularly on mating behavior. In this paper, the existence of mating mistakes (erroneous mating attempts) involving 13 Chinese stonefly species (belonging to nine genera and three families) is reported. These erroneous mating behaviors can be included into three different categories: mating attempts between conspecific males (including the formation of erroneous mating balls), mating attempts between different taxa (including displacement attempts during copulation), and mating-related behaviors with non-living objects. From these behaviors, some aspects of stoneflies during mating, such as the physical competition between males, the sensorial mechanisms implied in triggering a mating behavior, the conditions favoring the mating mistakes, and the possible consequences of interspecific mating in the hybrid production, are discussed.National Natural Science Foundation of China (No. 32170459; 31872266; 31071958)China Scholarship Council, the Project of Biological Resources Survey in Wuyishan National Park, Investigation and Evaluation of Insect Resources in Huangshan Scenic Spot (Phase I)Insect fauna of Qilian Mountain National Park (Qinghai)Volume of Lepidoptera and Diptera (procurement contract No. QHTX-2021-006, Administration of Qilian Mountain Nature Reserve, Qinghai Province

Divergent nucleic acid allocation in juvenile insects of different metamorphosis modes

This work was funded by the Regional Government of Andalusia (Excelencia P12-RNM327 Project to MVA). We thank J. M. Medina-Sánchez, J. M. Olalla, J. M. Luzón-Ortega, and I. López Lozano for their help in field sampling. S. Hitos is acknowledged for her contribution on laboratory analyses, J. M. Conde and R. Rubio de Casas for their helpful suggestions for data treatment, I. Peralta-Maraver for drawings of figure 4, and R. Davies for English writing assistance.Supplementary Information The online version contains supplementary material available at https://doi. org/10.1038/s41598-021-89736-w.Nucleic acids help clarify variation in species richness of insects having different metamorphosis modes, a biological conundrum. Here we analyse nucleic acid contents of 639 specimens of aquatic insects collected from four high mountain streams of Sierra Nevada in southern Spain to test whether the allocation to RNA or DNA content differs during ontogeny between juvenile insects undergoing direct (hemimetabolous) or indirect (holometabolous) metamorphosis. The results show that RNA content as a function of body mass was negatively correlated to insect body length in four out of six and three out of six of the holometabolan and hemimetabolan taxa, respectively. Although no significant differences in RNA content were found between holometabolans and hemimetabolans, the significant interaction between body length and metamorphosis mode for RNA and RNA:DNA indicates a strong ontogenetic component to RNA allocation. In addition, our finding of lower DNA content in holometabolans relative to hemimetabolans agree with the analysis of empirical genome data in aquatic and terrestrial insects, and extend to this class of arthropods the “growth rate-genome size-nutrient limitation” hypothesis that differences in allocation between RNA and DNA may reflect fundamental evolutionary trade-off of life-history strategies associated with high growth rates (and RNA content) in holometabolans at the expense of diminished genome sizes.Regional Government of Andalusia (Excelencia P12-RNM327 Project to MVA