Description of Laimaphelenchus belgradiensis sp nov (Nematoda: Aphelenchoididae) and its phylogenetic and systematic position within Aphelenchoidoidea

Abstract

Laimaphelenchus belgradiensis sp. nov. is described and illustrated, based on morphological, molecular and morphometric data. The new species belongs to the group of Laimaphelenchus species having a vulval flap. A unique combination of characters distinguishes this parthenogenetic species from others: annulated cephalic region; no labial disc; polygonal median bulb; offset tail terminus with four pedunculate tubercles in a square position that end in 10-12 finger-like protrusions. Morphologically, the new species resembles L. cocuccii and L. deconincki but differs from them by the body length, stylet length, distance from the anterior end to the median bulb, head annulations and tail shape. Bayesian phylogenetic analyses based on 18S and the D2/D3 segment of 28S rRNA genes were performed using sequences of species from 18 genera within the Aphelenchoidoidea. The resulting phylogenetic trees generated three distinct clades representing three families: Aphelenchoididae, Ektaphelenchidae and Parasitaphelenchidae. In the 18S tree L. belgradiensis sp. nov. forms a clade with L. penardi and in the 28S tree the new species is close to L. persicus and L. preissii.