Effects of Environmental Changes on Gerromorpha (Heteroptera: Hemiptera) Communities from Amazonian Streams

Abstract

The presence of environmental conditions that are suitable for the development of agricultural and cattle-raising activities has favored the expansion of land use in the Brazilian Amazon. This expansion changes the environmental conditions of aquatic ecosystems by altering the structure of the streambeds and the physicochemical conditions of the water. Therefore, this manuscript aimed to assess the effect of changes in environmental conditions along a gradient of different land uses on the richness and species composition of Gerromorpha (Heteroptera: Hemiptera) communities in streams from the Brazilian Amazon. We sampled Gerromorpha communities and environmental variables (physical structure of the habitat and physicochemical characteristics of the water) in 45 streams in the municipality of Paragominas in the state of Pará, Brazil. We then performed variation partitioning analyses to assess the relative contribution of habitat structure and water physicochemical variables on the richness and species composition. The Habitat Integrity Index (HII), which measures the habitat physical structure, was the best predictor of species richness. The HII and physicochemical variables were jointly the best predictors of species composition. Our results show that Gerromorpha communities respond to gradients of environmental anthropization in the Amazon region, which reinforces the importance of habitat integrity and water quality for the maintenance of Gerromorpha communities.

Genetic Diversity and Population Structure of Hemiculter leucisculus (Basilesky, 1855) in Xinjiang Tarim River

“…This could be because Taitema Lake is located at the end of the Tarim River, and the alluvial plain formed by three water systems of Tarim River, Qarqan River and Altun Rivers, with frequent water exchange [ 35 ]. There was increased gene flow between populations during floods [ 38 , 39 , 40 ].…”

“…In 1958, Bosten Lake introduced Cyprinus carpio , Carassius auratus , Hypophthalmichthys molitrix and Hypophthalmichthys nobilis directly or indirectly from the Yangtze River basin for economic benefits and H. leucisculus and Bosten male fish in the pond dominated [ 42 , 43 ]. High natural diffusion and human translocation are conducive to gene flow and high genetic diversity among river basins, which might help retain the invasive potential [ 38 ]. Therefore, it is speculated that H. leucisculus from Bosten Lake entered Taitema Lake to breed and then expanded into the Tarim River.…”

Aquatic and Semiaquatic Heteroptera (Hemiptera: Insecta) Distribution in Streams on the Cerrado–Amazon Ecotone in Headwaters of Xingu River

“…Among the studies on aquatic insects, there are few analyzing the relationship between the Heteroptera and environmental impacts [20][21][22]. Aquatic Heteroptera are divided into Gerromorpha, Nepomorpha, and Leptopodomorpha infra-orders that are cosmopolitans, not occurring just in Antarctica where major landmasses are absent [23].…”

“…Most of these insects are predators, except for some members of the Corixidae family. The Heteroptera are known for their ecological and environmental importance, such as the biological control of populations through predation, and thus, can be used as indicators of aquatic habitat quality [22,24,25]. Few studies have evaluated the effect of the anthropogenic impacts on the composition and structure of Heteroptera communities in the Cerrado-Amazon transition region [26], and little is known about the effects of changes on these organisms.…”

Chinches semiacuáticas (Hemiptera: Heteroptera: Gerromorpha) del Parque Nacional Natural Utría (Chocó, Colombia)

“…Las chinches semiacuáticas del infraorden Gerromorpha (Hemiptera: Heteroptera), son insectos adaptados a vivir en los cuerpos de agua y se les conoce como chinches patinadores gracias a su habilidad para caminar sobre la superficie del agua (Moreira, 2015). Estos hábitos han hecho que este grupo de insectos jueguen un papel fundamental en los ecosistemas acuáticos, de modo que su conocimiento es esencial para un adecuado manejo de los hábitats acuáticos al ser indicadores de la calidad biológica de estos ecosistemas (Mazzucconi et al, 2009;Moy et al 2022). Además, desempeñan un papel importante dentro de las cadenas tróficas en los ecosistemas acuáticos al servir de alimento a otros invertebrados como arañas, libélulas, escarabajos acuáticos y a vertebrados como peces, ranas, lagartijas, tortugas, cocodrilos, aves y murciélagos, y ser depredadores de artrópodos (Moreira, 2015).…”