Molecular characterization of Acrobeloides nanus (Nematoda: Cephalobidae) using 28S rDNA from South Africa

Acrobeloides nanus, belonging to the family Cephalobidae (Cephalobomorpha), are bacterivores that inhabit soil. Information on bacteria-feeding nematodes is sparse. Therefore, identifying this group of nematodes is important because they are one of the main consumers of soil bacteria. Hence, study on this group of nematodes is essential. This molecular study was conducted in 2024 at Limpopo University to identify the free-living bacterivores nematodes from South Africa's soils, using a 28S rDNA marker. The nematode was extracted using the tray method, and then its DNA was extracted using the Chelex method. The nematode was identified as A. nanus. In addition, molecular sequence data of the D2-D3 region of 28S rDNA from this species are provided as DNA barcode sequences. The Nblast analysis based on the 28S rDNA showed that South African A. nanus has a 99% similarity (KX669640) with the population of the Republic of Korea. Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as A. nanus in the same clade with highly supported (89%) bootstrap values. In conclusion, this species was properly identified using 28S rDNA. However, other rDNA markers are recommended to better understand Acrobeloides phylogeny.