Subfossil Chironomidae (Diptera) in surface sediments of the sinkholes (cenotes) of the Yucatan Peninsula: Diversity and distribution

Abstract

Cenotes (sinkholes), formed by the dissolution of the carbonate rock, are the most common waterbodies on the Yucatan Peninsula. Despite their unique features and great amount in the region, our knowledge on the biota of cenotes remains fragmentary. Within the present study we analysed chironomid remains from surface sediment of ten cenotes situated in SE Mexico. In total, 20 taxa of 17 genera were recorded, and the total diversity was estimated to ~30 taxa. The most common taxa were Polypedilum (Tripodura) sp., Tanytarsus ortoni-type, Fittkauimyia sp., Labrundinia sp. and Endotribelos sp. There was a great variability in head capsule abundance among cenotes, ranging from 1 to 64 individuals per site with significantly higher number of remains recorded in open cenotes compared to the closed, cavern types. The results indicate that beside ecological features, such as low trophy, oxygen depletion, simplified habitat structure and fish predation, there are also taphonomical processes connected to the specific nature of cenotes that can hinder the accumulation of biological remains in the sediment. We conclude that due to poor sedimentation and preservation of remains, cenotes have limited potential for palaeolimnological studies.

DNA Barcodes Applied to a Rapid Baseline Construction in Biodiversity Monitoring for the Conservation of Aquatic Ecosystems in the Sian Ka’an Reserve (Mexico) and Adjacent Areas

“…All aquatic ecosystems studied here, except Tres Reyes 1, are of transparent blue water (see Figure 2). Accordingly, most of the aquatic systems in the Yucatan Peninsula, which are oligotrophic, show an average Secchi disk of 7.6 m [40] and exhibit a predominant presence of diatoms [41].…”

Dna Barcodes, a Powerful Tool for a Rapid Construction of a Baseline and Conservation of Aquatic Ecosystems in Sian Ka’an Reserve (Quintana Roo State, Mexico) And Adjacent Areas

“…All aquatic ecosystems studied here, except Tres Reyes 1, are of transparent blue water (see Fig. 2), accordingly with most of the aquatic systems in the Yucatan Peninsula, which are oligotrophic, with an average Secchi disk of 7.6 m [37] and exhibit a predominant presence of diatoms [38].…”

“…Since data are absence-presence, variation species composition between sampling places was performed using the Sørensen index of dissimilarity [37][38][39]. All analyses were performed with Betapart Package in R software [36].…”

“…Chironomids were represented basically by pupae, but some adults emerged inside the trap. Recently, in a study about subfossil Chironomidae present in sediments from Yucatan Peninsula, the maximum resolution was to groups of species, and the authors concluded that due to poor sedimentation and preservation of remains, cenotes have limited potential for palaeolimnological studies [37]. This conclusion highlights the urgency to bio-assess this community at the present day.…”

A guide to the identification of subfossil non-chydorid Cladocera (Crustacea: Branchiopoda) from lake sediments of Central America and the Yucatan Peninsula, Mexico: part I

“…These waterbodies were mainly lakes varying in depth, but there were also cenotes and smaller ponds. Most of the studied waterbodies have already been the subject of studies of various limnological characteristics (Pérez et al 2011), bioindicators such as ostracods, chironomids, and cladocerans together (Pérez et al 2013), as well as the diversity and distribution of pollen (Correa-Metrio et al 2011;Franco-Gaviria et al 2018a), cladocerans (Wojewódka et al 2016), ostracods (Cohuo et al 2016), and chironomids (Hamerlik et al 2018). Additionally, the DNA of the ostracods has been analyzed (Macario-Gonzáleza et al 2018), along with some paleolimnological studies (Curtis et al 1998;Escobar et al 2012;Diaz et al 2017;Franco-Gaviria et al 2018b) having been conducted.…”