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Description of Oscheius cyrus n. sp. (Nematoda: Rhabditidae) as new entomopathogenic nematode from Iran

Published online by Cambridge University Press:  19 September 2022

K. Kuhestani
Affiliation:
Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
J. Karimi*
Affiliation:
Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
E. Shokoohi
Affiliation:
Department of Plant Production, Soil Science and Agricultural Engineering, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa
A. Makhdoumi
Affiliation:
Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
*
Author for correspondence: J. Karimi, E-mail: jkb@um.ac.ir

Abstract

A new species of the genus Oscheius, Oscheius cyrus n. sp., collected in the moist soils taken from forest heights in the north of Iran, is recorded. A comprehensive description, comprising molecular (internal transcribed spacer (ITS), 18S, and 28S rDNA genes) information, morphometrics data, light microscope and scanning electron microscope images, is supplied. The species resembles Oscheius myriophilus. However, the highest ranges for female body length, female tail, infective juvenile tail length, median bulb, absence of epiptygma and lateral field incisures number vary. The new species was distinguished from Oscheius insectivorus by the general lip region. The male was not found. Molecular analysis showed that the new species has the most similarity to O. myriophilus both in the ITS and 18S regions. Morphological and molecular data confirmed its belonging to the Insectivora-group. Furthermore, the species of Ochrobactrum pseudogrignonense was reported as a dominant associated bacterium of the new Oscheius species. Finally, the mortality of the host after seven days varied from 20% to 82.5%, depending on nematodes’ concentration.

Type
Research Paper
Copyright
Copyright © The Author(s), 2022. Published by Cambridge University Press

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