This table contains all high-resolution Chironomid data accompanying Schouten et al., 2026 in prep. All analytical data were attained from a sediment core taken in Mezzano (42°36'42'' N, 11°46'12'' E, 452 m.a.s.l.); a small 'maar'-lake (0.5 km2; 31 m deep) lake in Lazio, located in Central Italy. The data was collected to get a comprehensive understanding of the interaction between, anoxia, temperature and total trophic productivity in the timeframe 12 ka BP - 15 ka BP. Data were attained in 2019 and 2020. Sediments were collected using a piston corer in 3m segments (UWITEC - style). The sediment cores were cut in 1m pieces and subsampled. The age-depth relationship is established with a Bayesian model blending 7 14C dates, 3 recalibrated bulk 14C dates, and an ash layer. 6-11 cm3 of wet sediment were treated with 5% KOH and washed through a 200 and 100-µm mesh size sieve. Chironomid head capsules (HC) were picked in a modified Bogorov counting tray under a dissecting microscope at 40× magnification and mounted on permanent slides with Hydro-Matrix® mounting medium. Taxonomic identification was performed under an optical microscope (Carl Zeiss Primo Star iLed) at 400× magnification, A minimum of 50 HC per sample was identified (Heiri and Lotter, 2001), except for two samples from the lowermost part of the core (15.2-14.6 cal ka BP), which contained 23 and 31 HC, respectively. Half of a mentum was counted as one half, and HC with more than half a mentum were counted as one HC. Taxonomic identifications followed Brooks et al. (2007) and Rieradevall and Brooks (2001).