Basilaphelenchus hyrcanus n. sp. (Rhabditida: Tylaphelenchinae) associated with bark of a beech tree (Fagus orientalis Lipsky) from northern Iran

Esmaeil Miraeiz,Ramin Heydari,Zahra Tanha Maafi,Behrouz Golhasan

doi:10.21307/jofnem-2021-028

Abstract

Basilaphelenchus hyrcanus n. sp., the sixth species of the newly established genus was isolated during a nematode survey associated with bark samples of beech tree in northern Iran, which differs from the other species by body size, stylet length, metacorpus structure, and tail characters of both genders. The new species is also characterized by elevated cephalic region with sclerotised vestibule, posteriorly directed stylet knobs, well-developed metacorpus filling corresponding body region, position of excretory pore at the level of base of metacarpus, length of post uterine sac by 38–60 μm long, conoid elongate tail by sharp to finely rounded tip in female. Based upon the morphological characteristics and phylogenetic analyses of partial 18 S and D2-D3 28 S rDNA segments, the new species mostly resembles B. magnabulbus. However, B. hyrcanus n. sp. is clearly different from this species by having a longer stylet, different position of the excretory pore, a different male tail tip characters and 4.4 and 13.2% sequence divergences in 18 S and D2-D3 28 S, respectively.

Highlights

Aphelenchoididae Skarbilovich, 1947 is a diverse family that includes fungal feeders, plant parasites, insect parasites and predators (Hunt, 1993, 2008)
The molecular phylogenetic relationships of Aphelenchoididae inferred from 18 S and 28 S D2-D3 of rDNA by Kanzaki and Giblin-Davis (2012) showed four major clades
Basilaphelenchus currently consists of five nominal species of which four species have been proposed from Iran, namely B. persicus Pedram et al, 2018, B. brevicaudatus Mirzaie Fouladvand et al, 2019a, B. gorganensis Mirzaie Fouladvand et al, 2019b, and B. magnabulbus Aliramaji et al, 2019a

Summary

Introduction

Aphelenchoididae Skarbilovich, 1947 is a diverse family that includes fungal feeders, plant parasites, insect parasites and predators (Hunt, 1993, 2008). Kanzaki et al (2014) erected a new subfamily Tylaphelenchinae including Pseudaphelenchus Kanzaki et al, 2009 and Tylaph elenchus Rühm, 1956 assigning them to clade one. Pedram et al (2018) added a new genus, Basilaphelnchus Pedram et al, 2018, to this subfamily. They considered Albiziaphelenchus Bajaj, 2012 as the fourth genus for Tylaphelenchinae. Based on partial 18 S and 28 S D2D3 rDNA sequences, the phylogenetic relationships with other genera of Aphelenchoididae are discussed. The objectives of the present study were to (a) characterize the new species by the morphological features (b) determine the molecular phylogenetic affinities of B. hyrcanus n. The objectives of the present study were to (a) characterize the new species by the morphological features (b) determine the molecular phylogenetic affinities of B. hyrcanus n. sp. with closely related species using both partial 18 S and 28 S D2-D3 rDNA sequences

Objectives

Methods

Results

Conclusion