Incidence of deformities and variation in shape of mentum and wing of Chironomus columbiensis (Diptera, Chironomidae) as tools to assess aquatic contamination

Abstract

Constantly, aquatic ecosystems are under pressure by complex mixtures of contaminants whose effects are not always easy to evaluate. Due to this, organisms are sought in which early warning signs may be detected upon the presence of potentially toxic xenobiotic substances. Thereby, the study evaluated the incidence of deformities and other morphometric variations in the mentum and wing of Chironomus columbiensis exposed to water from some of the Colombian Andes affected by mining, agriculture, and cattle raising. Populations of C. columbiensis were subjected throughout their life cycle (24 days) for two generations (F1 and F2). Five treatments were carried out in controlled laboratory conditions (water from the site without impact, site of mining mercury, mining mercury + cyanide, cattle raising, and agriculture) and the respective control (reconstituted water). Thereafter, the percentage of deformities in the mentum was calculated, and for the morphometric analysis 29 landmarks were digitized for the mentum and 12 for the wing. As a result, four types of deformities were registered in the C. columbiensis mentum, like absence of teeth, increased number of teeth, fusion and space between teeth, none of them detected in the individuals from the control. Additionally, the highest incidence of deformity in F1 occurred in the treatment of mining mercury, while for F2 this took place in the treatments of mining mercury + cyanide, cattle raising and agriculture. Differences were also found with respect to the morphometric variations of the mentum and wing of C. columbiensis among the control and the treatments with water from the creeks intervened. The treatments of mining mercury + cyanide and agriculture had the highest morphological variation in the mentum and wing of C. columbiensis. The results suggest that the anthropogenic impacts evaluated generate alterations in the oral apparatus of the larval state of C. columbiensis and in the adult state provoke alterations in the wing shape (increased width and reduced basal area). These deformities may be related to multiple stress factors, among them the xenobiotics metabolized by the organisms under conditions of environmental contamination.

Histological description of immature Chironomus columbiensis (Diptera: Chironomidae): A potential contribution to environmental monitoring

“…The 10 individuals of C. columbiensis used in this study were obtained from a colony maintained at the Laboratory of Zoology of the Universidad de Caldas (Manizales, Caldas, Colombia), confirmed by Trivinho‐Strixino (Universidade Federal de São Carlos‐Brazil‐Departamento de Hidrobiologia), under controlled temperature (22 ± 2°C), humidity (65 ± 10%), and photoperiod (12 hr light/12 hr darkness), semi‐soft reconstituted water, constant aeration, and TetraMin® crushed food (Montaño‐Campaz et al, ).…”

“…C. columbiensis was first described in Cali‐Colombia by Wülker, Sublette, Morath, and Martin (). Larvae of C. columbiensis have been used in environmental quality assessment in Colombia (Montaño‐Campaz, Gomes‐Dias, Restrepo, & García‐Merchán, ). In particular, Montaño () showed that C. columbiensis is more sensitive to heavy metals compared to other chironomid species broadly used ecotoxicology, such as Chironomus calligraphus , Chironomus tentans, and Chironomus riparius .…”

Chironomus columbiensis (Diptera: Chironomidae) as test organism for aquatic bioassays: Mass rearing and biological traits

“…Chironomus columbiensis is one of the few species of this group identified in Colombia, described by Wülker et al (1989) and has been reported in Colombia, Brazil, Guatemala and the United States (ZipcodeZoo 2015), but its biology and ecology are still little known (Montaño-Campaz et al 2019, Ospina-Pérez et al 2019. Therefore, the objective of this study was to know the effects of temperature, availability food and type of water in the laboratory rearing of the species Chironomus columbiensis.…”

A chromosome level genome assembly of Propsilocerus akamusi to understand its response to heavy metal exposure

“…Although the pattern of distribution of chironomids can also serve as an indicator of the urban pollution of stream systems, molecular alterations can be complementary to conventional assessment approaches, in which genetic biomarkers were proposed as early indicators of chemical toxicity. Therefore, some species have been used as target organisms for the assessment of aquatic toxicology, especially Chironomus species, due to their high degree of sensitivity (Martínez‐Paz, 2018; Montaño‐Campaz et al, 2019). However, only a handful of genes (cytochrome P450, hormonal receptors, small heat shock proteins, and α‐enolase) have been demonstrated to be correlated with the tolerance/resistance to insecticides or heavy metals in chironomids (Martín‐Folgar & Martínez‐Guitarte, 2019; Nair et al, 2013; Planelló et al, 2010; Zheng et al, 2018).…”