Knowledge about microorganisms present in the most diverse habitats represents a potential source, not only for taxonomic guidelines that aid in correct identification, but also for potential genes of interest for biotechnological processes. The Flavobacterium genus is composed of species inhabiting diverse sources, from soil, ice, freshwater, to species pathogenic for fish. Species of this genus contain in their genomes several genes responsible for denitrification processes, thus finding potential niches for colonization in the soil and aquatic habitats. Therefore, the present study reports the proposal of a new species of the genus Flavobacterium . Strain PRF/RAS-24, isolated from a water sample from a recirculating tank of tilapia production in the state of Paraná, Brazil. The sample was diluted 1:100 and plated on G medium supplemented with tobramycin (1 µg x mL-1). After 48 hours of incubation at 28°C, colonies with notable motility were observed, lacking defined borders due to the high rate of gliding motility. Multiple colony formation centers were identified, making it difficult to quantify the number of colonies due to their gliding capacity. So, motility was evaluated through previously published methodology. As a result colony diameter reached 55mm after 72 hours at 28ºC. Do not grow well at 0.8% NaCl and absence of growth at 2%. G media supplemented with 2% skimmed milk was used to observe casein hydrolytic enzyme production by the strain, confirming this phenotypic virulent trait. Cell morphology was visualized by Gram staining, confirming the morphology of short Gram negative rods. Comparative analyses of the 16S rRNA gene of the isolate against the NCBI type strain database revealed similarities with Flavobacterium tagetis GN10 (98.6%), F . tristanium GB56.1 (98.52%), F . zhairuoense A5.7, and F . anhuiense D3 (both with 98.15%), the nucleotide collection as database show best hits 98.89-99.88% similarity with sequences assigned as Flavobacterium sp., isolates were from metagenomic gut microbiota and water of ornamental fish aquaria. Genomic sequencing was performed using MiniIon mk1D (Oxford Nanopore Technologies). Raw data was generated. Pod5 was base-called using the HAC model at Dorado (ONT). FastQ reads were adapter/barcode trimmed by Porechop , and before assembly and polishing using Canu and Racon , respectively. NanoFilt was used to remove >-q 15 bases. The final assembly was composed of seven contigs with an average size of 748 kb and a G+C content of 49.8%. Genomes of the species with the highest 16S rRNA gene similarity were downloaded from the NCBI database and compared to obtain average nucleotide identity (ANI) and digital DNA-DNA hybridization with the fastANI software. As a result, the highest hybridization index (78.42%) and ANI (88.69%) were with F . anhuiense . RCM74 assembled metagenomic data. These ANI vallue are below the cutoff > or = 96, proposed for species delineation, based on genomic data. So as for the G+C content of 34 % present by F. anhuiense versus 49.8% in % the proposed novel species.