The Comparative Gut Content Analysis of Some Chironomidae Larvae Living in the Freshwaters at Northern Thrace Region of Turkey

Abstract

The roles of larval chironomids in the food chain of both the lotic and the lentic ecosystems are very important. On the one hand, chironomid larvae feeding on algae, diatoms, rotting organic matter, plant, and animal residues also play an important role in these systems as a source of food for other carnivores and omnivorous organisms. In this study, the gut contents of Cryptochironomus defectus (Kieffer, 1913), Cladotanytarsus mancus (Walker, 1856), Polypedilum scalaenum (Schrank, 1803), Tanypus kraatzi (Kieffer, 1912) collected from the freshwater ecosystems located in the northern parts of the Thrace region of Turkey were analyzed to compare their feeding habits. As a result of the analysis, it was determined that while plant fragments were dominant in C. defectus species in the gut content (44.3%), algae were dominant for C. mancus (44.7%), P. scalaenum (63.5%), T. kraatzi (65%). According to the results of the Shannon-Wiener (H') index species, diversity of the P. scalaenum was found to be the highest among the larvae (H'= 1.345). Also, according to the Bray-Curtis similarity index, the most similar types of gut contents were P. scalaenum and C. defectus (38%). This low rate indicated that the species have different food preferences.

Cyanobacteria and Macroinvertebrate Relationships in Freshwater Benthic Communities beyond Cytotoxicity

“…However, cyanobacteria contain nutrients and active macromolecules, such as pigments, carbohydrates, lipids (including essential fatty acids), proteins, vitamins, and minerals, which are necessary for the growth and maturation of macroinvertebrates [ 76 , 77 , 81 , 82 , 83 ]. A gut content analysis (microscopy, serology or DNA) has proven that certain grazer invertebrates feed on cyanobacteria [ 30 , 78 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 ], and they even prefer filamentous species [ 84 , 86 , 90 , 93 ], but their ingestion in other grazers may accidentally occur because some cyanobacteria species are usually found as epiphytes of macrophytes, or as part of complex biofilms, periphyton and detritus [ 2 , 3 , 83 , 94 , 95 ]. This dichotomy has led us to wonder whether the simple detection of cyanobacteria in grazers’ gut contents can be nutritionally considered by proposing an enzyme analysis as the most appropriate way to confirm that invertebrates have the capacity to digest cyanobacteria and to absorb their nutrients [ 84 ].…”

Profiling Analysis of Filter Feeder Polypedilum (Chironomidae) Gut Contents Using eDNA Metabarcoding Following Contrasting Habitat Types—Weir and Stream

“…Filter feeder chironomid depends upon the food available in the habitats [ 47 ]. Chlorophyta is a dominant food item [ 8 , 12 ]; specifically, green algae [ 11 ] and Diatomea [ 7 ] in the gut content of chironomid have also been reported in previous studies based on microscopic observation. Certainly, these groups have been reported in water sample (eDNA) based content exploring the biodiversity of the freshwater habitat [ 19 ].…”

“…A similar analysis, reported by Butakka et al (2016) [ 7 ], could categorize the food content as algae, fungal spores, and plant fragments but there was inadequacy in diverse composition and high-taxonomic resolution. Certain observations could identify phytoplankton [ 5 , 8 ], mostly algae [ 9 , 10 ] and detritus [ 11 , 12 ], as the major gut content in the chironomid. However, these results could not profile detailed taxonomic specificity and diversity of food sources.…”