Evolutionary tracks of chromosomal diversification in Trichopsis (Anabantiformes, Osphronemidae) fishes: New insights from a molecular cytogenetic perspective

BOONYADA MINGKWAN (Department of Biology, Faculty of Science, Khon Kaen University. Muang, Khon Kaen 40002, Thailand)
FRANCISCO DE MENEZES CAVALCANTE SASSI (Departamento de Genética e Evolução, Universidade Federal de São Carlos. Rodovia Washington Luiz Km. 235, C.P. 676, São Carlos, SP, 13565-905, Brazil)
NAWARAT MUANGLENM (Department of Fisheries, Faculty of Agricultural Technology, Sakon Nakhon Rajabhat University. Sakon Nakhon, 47000, Thailand)
SITTHISAK PINMONGKHONKUL (Department of Biology, School of Science, University of Phayao. Muang, Phayao 56000, Thailand)
KRIT PINTHONG (Department of Fundamental Science, Faculty of Science and Technology, Surindra Rajabhat University. Muang, Surin 32000, Thailand)
SAMPAN TONGNUNUI (Department of Conservation Biology, Mahidol University. Kanchanaburi Campus, Sai Yok, Kanchanaburi Province 71150, Thailand)
PUN YEESIN (Department of Technology and Industries, Faculty of Science and Technology, Prince of Songkla University. Pattani Campus, Muang, Pattani 94000, Thailand)
ALONGKLOD TANOMTONG (Department of Biology, Faculty of Science, Khon Kaen University. Muang, Khon Kaen 40002, Thailand)
THOMAS LIEHR (University Hospital Jena, Friedrich Schiller University, Institute of Human Genetics. Jena 07747, Germany)
MARCELO DE BELLO CIOFFI (Departamento de Genética e Evolução, Universidade Federal de São Carlos. Rodovia Washington Luiz Km. 235, C.P. 676, São Carlos, SP, 13565-905, Brazil)
WEERAYUTH SUPIWONG (Applied Science Program, Faculty of Interdisciplinary Studies, Khon Kaen University. Nong Khai Campus, Muang, Nong Khai 43000, Thailand)

Biodiversitas Journal of Biological Diversity
Vol. 24 No. 3 (2023)

Abstract. Mingkwan B, Sassi FDMC, Muanglenm N, Pinmongkhonkul S, Pinthong K, Tongnunui S, Yeesin P, Tanomtong A, Liehr T, Cioffi MDB, Supiwong W. 2023. Evolutionary tracks of chromosomal diversification in Trichopsis (Anabantiformes, Osphronemidae) fishes: New insights from a molecular cytogenetic perspective. Biodiversitas 24: 1551-1559. This study investigated the chromosomes of three Trichopsisspecies (namely Trichopsis pumila, Trichopsis vittata, and Trichopsis schalleri) using conventional (Giemsa stain, Ag-NOR) and molecularcytogenetic techniques. Fluorescence in situ hybridization (FISH) with repetitive DNAs, including 5S and 18S rDNAs, and microsatellites as probes were also performed. Our results indicated a conserved diploid number of 46 (2n) for all analyzed species of both sexes, although varying in their karyotype structure. Furthermore, T. schalleri and T. vittata karyotypes were presented with only acrocentric chromosomes (46a), while T. pumila had a submetacentric pair in addition to acrocentric ones (2sm+44a). Positive Ag-NOR sites were differentially found in each species adjacent to the acrocentric chromosome's centromeric and/or interstitial sub-centromeric regions. Both 5S and 18S rDNAs vary between the analyzed species, but all were localized in multiple sites. However, the distribution pattern of microsatellites differed in each species, mostly scattering at peri-centromeric and telomeric regions. These findings show that Trichopsis species, while having a conserved diploid number, differ significantly in the distribution of repetitive sequences in their karyotypes, particularly for rDNAs. These species-specific patterns can be useful for characterizing and identifying further different species and examining the evolutionary mechanisms that drove the evolution of these fishes' karyotypes.