Abundance, Richness, Seasonal and Altitudinal Dynamics of Aquatic True Bugs (Heteroptera) in Mountain Wetlands of Argentina

Abstract

Mountain wetlands provide unique information because their biota is highly specific and contributes significantly to regional diversity. The goals of this study were assessing altitudinal and temporal variation in the distribution of Heteropteran assemblages in mountain wetlands; and studying the phenology of the most abundant species. All stages of Heteroptera and data on environmental variables were collected monthly over one year from five mountain wetlands. A simple community structure, and also a low richness of aquatic true bugs, composed of four Heteropteran families (C o r i x i d a e , B e l o s t o m a t i d a e , N o t o n e c t i d a e a n d Gelastocoridae), characterized our ponds. Richness and abundance varied temporally and spatially (p < 0.0001); and increased at higher elevations. Additionally, the highest abundance of cold stenothermal species occurred at the highest altitudes where harsh conditions are prevalent. Ectemnostega (E.) quadrata and S. (T.) jensenhaarupi, both endemic to the Andes region, were the most abundant species. Both these species showed univoltine cycles and overwintered as adults. Biodiversity of the Heteroptera reached maximum values in summer when water temperature increased. Temporal and spatial monitoring studies provide key information on the distribution, diversity, and habitat requirements of Heteropteran species as well as on conservation and management of these vulnerable habitats and species which are faced with climate warming.

Artificial reservoirs complement natural ponds to improve pondscape resilience in conservation corridors in a biodiversity hotspot

“…High beetle diversity probably arises from high species turnover between lentic and lotic habitats at higher elevations [ 75 ; 76 ] and high microhabitat availability in natural ponds at low elevations respectively [ 25 ]. Increased aquatic bug species richness and diversity can be associated with increased elevation [ 57 ], but we did not find that here across our short elevation range. Aquatic bugs in this area are mainly widespread generalists [ 35 ; 36 ] possessing great plasticity [ 77 ], allowing them to occupy a variety of aquatic environments.…”

“…Artificial reservoirs had less marginal grasses and forbs coverage, more reed coverage, and were rich in submerged aquatic weeds (dominated by Elodea spp.). These seemingly open habitats favour early aquatic beetle and bug colonization [ 55 ; 56 ; 57 ]. However, consistent with recent suggestions [ 19 ; 22 ; 58 ], beetle species richness and diversity was positively correlated with increased forb cover in artificial reservoirs.…”

“…The beetles and most bugs sampled here are water-dwelling during their adult and larval stages, and might also be capable of assessing water biochemistry directly. Nevertheless, moderate water temperature increases activity [ 43 ; 57 ] and shortens larval development time [ 10 ] for dragonflies, beetles and bugs occupying both natural ponds and artificial reservoirs. For these reasons, most aquatic beetles occupy ponds characterized by moderate water temperature, yet dragonflies (and their larvae) and bugs may be able to tolerate slightly elevated water temperature.…”

Aquatic insects decline in abundance and occupy low‐quality artificial habitats to survive hydrological droughts

“…Adult aquatic beetles and bugs are atmospheric breathers, and do not rely on dissolved oxygen directly, yet bug species richness showed some response to water temperature and dissolved oxygen. Most bug species are early colonisers of water bodies and are physically and physiologically enabled to occupy lentic habitats fluctuating in daily/seasonal water temperature and dissolved oxygen (Florencio, Serrano, Gómez‐Rodriguez, Millán, & Paz‐Paniagua, ; Scheibler, Melo, Montemayor, & Scollo, ), but high concentrations of dissolved oxygen and low water temperature create suitable conditions for predators, influencing the occupancy and diversity of aquatic bugs (Lytle, ).…”

When is protection not conservation? A case study of semi‐natural freshwater marshes in Hong Kong

“…Throughout Asia, small paddy fields have tended to be abandoned in recent years (Katayama et al, 2015;Ba et al, 2018). Although these habitats can support a variety of rare aquatic insects for a transitional period (Yoon et al, 2010;Yeh, Lee & Wong, 2015;Scheibler et al, 2016), they eventually become transformed into terrestrial environments. For instance, the soil moisture of semi-natural marshes in Korea had begun to decrease 10 years after abandonment and, unless inhibited by waterlogging, terrestrialization might be completed within four decades (Lee, You & Robinson, 2002).…”