Phylogenetic relationships of three families of the suborder Mononchina Kirjanova & Krall, 1969 inferred from 18S rDNA

Abstract

Mononchida is an order of predatory nematodes and includes the suborders Bathyodontina and Mononchina. In this survey, sequences of the 18S rDNA were amplified and used to reconstruct the phylogeny of the Mononchina. Phylogenetic analyses using Neighbour Joining (NJ) and Maximum Likelihood (ML) were employed with five outgroup taxa and 65 mononch sequences including 14 new sequences from Iran. Both analyses indicated that the Anatonchus is monophyletic. Actus was placed as the sister group of Mylonchulus with weak and strong support, respectively, from the ML and NJ analyses. In both phylogenetic analyses, trees obtained from SSU rDNA alignments were subdivided into five highly- or moderately-supported clades, designated Clade I: Mylonchulus spp., Clade II: Actus salvadoricus, Clade III: Anatonchus spp., a group comprising the genera Clarkus, Coomansus, Miconchus and Prionchulus, Clade IV: Mononchus spp., and Clade V: Granonchulus sp. The 18S rDNA analysis demonstrated that this region of the nuclear genome can be used to resolve the relationships of members of this suborder.

Molecular Character of Mylonchulus hawaiiensis and Morphometric Differentiation of Six Mylonchulus (Nematoda; Order: Mononchida; Family: Mylonchulidae) Species Using Multivariate Analysis

“…The present results indicate that 18S rDNA sequence data are a valuable marker for the phylogenetic analysis within Mylonchulus species. This agrees with the previous result obtained [5,11,35]. Tree topology using Bayesian inference shows that M. hawaiiensis stand separately, which contrasts with the result obtained by Olia et al [35].…”

“…Therefore, the variation that exists may be due to the geographic location. Shokoohi et al [11] and Koohkan et al [5] indicated that the populations of Mylonchulus make a monophyletic group. The present study obtained the same result.…”

“…In Nematoda, the order Mononchida [2,3] comprises predators found in various habitats, including terrestrial to aquatic [4]. These groups of nematodes play an essential role in the dynamics of the fauna of the soil [5]. Mononchida members play a crucial role in decreasing the plant-parasitic nematodes; however, this predatory behaviour is mainly investigated in the controlled environment [6].…”

“…Therefore, their precise identification helps to find out a suitable predator to combat the plant-parasitic nematodes in future research. The genus Mylonchulus [8] (Nematoda; order: Mononchida; family: Mylonchulidae), is a broadly distributed taxon with six species being reported from Iran [5,6,[9][10][11][12][13][14][15][16][17]. Morphology, morphometrics, and molecular characters are the primary distinguishing tool for predator nematodes [4,5].…”

“…The genus Mylonchulus [8] (Nematoda; order: Mononchida; family: Mylonchulidae), is a broadly distributed taxon with six species being reported from Iran [5,6,[9][10][11][12][13][14][15][16][17]. Morphology, morphometrics, and molecular characters are the primary distinguishing tool for predator nematodes [4,5]. However, in some species of the Mylonchulus, the morphology and morphometrics overlap [4], so species identification becomes problematic.…”