Data from: Molecular circadian rhythms are robust in marine annelids lacking rhythmic behavior

# Data from: Molecular circadian rhythms are robust in marine annelids lacking rhythmic behavior Here we described the data provided in addition to the publication: **Molecular circadian rhythms are robust in marine annelids lacking rhythmic behavior** (doi: 10.1371/journal.pbio.3002572). For further details on how the data was generated, please consult the original publication. Reference transcriptome description: The reference transcriptome used for read mapping was created from samples of regenerated *Platynereis dumerilii* tail pieces (newly grown blastema + adjacent old segment) collected at different stages of regeneration (0, 1, 2, 3 and 5) staged according to Planques et al. 2019 [1]. Per regeneration stage, 3 replicates were collected (n=15 samples total). After library preparation with poly-A enrichment, samples were sequenced on an Illumina NovaSeq System (S1 flow cell, 100bp paired-end reads). The sequencing produced ~141 million reads (after standard quality control) that were assembled into a de novo transcriptome of 364,574 transcripts incl. isoforms (GC content: 39.65%, median/mean transcript length: 356bp/810.65bp). BUSCO analysis showed that 98.9% of near-universal single-copy orthologs were included [2] The transcriptome is provided in FASTA-format with all 364,574 transcripts listed. Trimmed/filtered reads of samples from rhythmic vs. arrhythmic phenotype transcriptome comparison: Samples of phenotypically rhythmic or arrhythmic worms collected over the 24h cycle were sequenced as paired-end reads on a Illumina NextSeq550 System (see methods of associated paper for details). For each sample (n=36 total), reads after trimming/filtering are provided as compressed fastq-files. The naming is based on the phenotype (R, A), sampling time point (ZT00, ZT04, ZT08, ZT12, ZT16, ZT20), replicate (1, 2, 3), and an indicator for forward/reverse reads (1, 2). For example, the file ‘R_ZT08_1_2.trim.fastq.gz’ contains the trimmed/filtered reverse reads of replicate 1 collected at time point ZT08 from rhythmic worms. Furthermore, a FastQC quality report is provided for each file. Python code for binary behavior reproducibility analysis: The presented code was used to determine the reproducibility of diel/circadian worm locomotor behavior as described in tzhe publication. R-script for GO-term analysis incl. associated files: The R-script was used to determine the enrichment of biological processes based on the trascriptome expression data. The file includes the R-script as well as the other files mentioned in the script and needed to re-create the analysis. Dryad references: 1\. Planques A, Malem J, Parapar J, Vervoort M, Gazave E. Morphological, cellular and molecular characterization of posterior regeneration in the marine annelid *Platynereis dumerilii*. Dev Biol. 2019;445: 189–210. doi:10.1016/j.ydbio.2018.11.004 2\. Manni M, Berkeley MR, Seppey M, Simão FA, Zdobnov EM. BUSCO Update: Novel and Streamlined Workflows along with Broader and Deeper Phylogenetic Coverage for Scoring of Eukaryotic, Prokaryotic, and Viral Genomes. Mol Biol Evol. 2021;38: 4647–4654. doi:10.1093/molbev/msab199