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[Display omitted] • maTs , GTs and VSs showed differential evolution patterns in eukaryotes. • DD37D and DD39D family composed an independent clade, with close to DD41D and DD34D. • HT might exist a lower rate of maTs between invertebrates and GTs between land plant. • Most of maTs and GTs might encoded active transposases possess intact characters. DNA transposons play a significant role in shaping the size and structure of eukaryotic genomes. The Tc1/mariner transposons are the most diverse and widely distributed superfamily of DNA transposons and the structure and distribution of several Tc1/mariner families, such as DD35E/ TR , DD36E/ IC , DD37E/ TRT , and DD41D/ VS, have been well studied. Nonetheless, a greater understanding of the structure and diversity of Tc1/mariner transposons will provide insight into the evolutionary history of eukaryotic genomes. Here, we conducted further analysis of DD37D/ maT and DD39D (named Guest , GT), which were identified by the specific catalytic domains DD37D and DD39D. Most transposons of the maT family have a total length of approximately 1.3 kb and harbor a single open reading frame encoding a ~ 346 amino acid (range 302–398 aa) transposase protein, flanked by short terminal inverted repeats (TIRs) (13–48 base pairs, bp). In contrast, GT s transposons were longer (2.0–5.8 kb), encoded a transposase protein of ~400 aa (range 140–592 aa), and were flanked by short TIRs (19–41 bp). Several conserved motifs, including two helix–turn–helix (HTH) motifs, a GRPR (GRKR) motif, a nuclear localization sequence, and a DDD domain, were also identified in maT and GT transposases. Phylogenetic analyses of the DDD domain showed that the maT and GT families each belong to a monophyletic clade and appear to be closely related to DD41D/ VS and DD34D/ mariner. In addition, maT s are mainly distributed in invertebrates (144 species), whereas GT s are mainly distributed in land plants through a small number of GT s are present in Chromista and animals. Sequence identity and phylogenetic analysis revealed that horizontal transfer (HT) events of maT and GT might occur between kingdoms and phyla of eukaryotes; however, pairwise distance comparisons between host genes and transposons indicated that HT events involving maT s might be less frequent between invertebrate species and HT events involving GT s may be less frequent between land plant species. Overall, the DD37D/ maT and DD39D/ GT families display significantly different distribution and tend to be identified in more ancient evolutionary families. The discovery of intact transposases, perfect TIRs, and target site duplications (TSD) of maT s and GT s illustrates that the DD37D/ maT and DD39D/ GT families may be active. Together, these findings improve our understanding of the diversity of Tc1 / mariner transposons and their impact on eukaryotic genome evolution. [ABSTRACT FROM AUTHOR]