<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>During a survey in Golestan province, north Iran, two populations belonging to the family Tylenchidae were recovered in association with <italic>Quercus</italic> sp., and a rotten wood sample of an unidentified forest tree. The first recovered species was mainly characterized by having a disc-like differentiation in the frontal end under the light microscope (LM), proposing it as a tentative member of the genus <italic>Discotylenchus</italic>. Detailed morphological studies using scanning electron microscope (SEM), however, did not reveal a true disc, but showing the smooth cephalic region, and a narrow annulus behind the cephalic plate. Based upon the cephalic region structure, and by lacking a true disc, the species was identified as a member of the genus <italic>Filenchus</italic>. This population was further characterized by 555 to 618 μm long females, lateral fields with four incisures, 9 to 10 μm long stylet, spermatheca large, including spheroid sperm, post-vulval uterine sac (PUS) 8 to 12 µm long and gradually tapering to an elongate conoid tail with pointed tip. It was compared with relevant species of <italic>Filenchus</italic> having four incisures in the lateral fields and similar general morphology. By having a disc-like differentiation in the frontal end under the LM, it was further compared with three similar known species of <italic>Discotylenchus</italic>. The morphological comparisons with species under two aforementioned genera showed the recovered population belongs to an unknown species, described herein as <italic>Filenchus pseudodiscus</italic> n. sp. The molecular phylogenetic relationships of the new species using partial small and large subunit ribosomal RNA gene (SSU and LSU D2-D3 rDNA) sequences were reconstructed and discussed. <italic>Malenchus gilanensis</italic>, the second recovered and studied species was originally established based upon traditional criteria. An updated LSU phylogeny of the genus <italic>Malenchus</italic> by including <italic>M. gilanensis</italic> was also presented and its results were discussed.</p>
</abstract>

During a survey in Golestan province, north Iran, two populations belonging to the family Tylenchidae were recovered in association with Quercus sp., and a rotten wood sample of an unidentified forest tree. The first recovered species was mainly characterized by having a disc-like differentiation in the frontal end under the light microscope (LM), proposing it as a tentative member of the genus Discotylenchus. Detailed morphological studies using scanning electron microscope (SEM), however, did not reveal a true disc, but showing the smooth cephalic region, and a narrow annulus behind the cephalic plate. Based upon the cephalic region structure, and by lacking a true disc, the species was identified as a member of the genus Filenchus. This population was further characterized by 555 to 618 μm long females, lateral fields with four incisures, 9 to 10 μm long stylet, spermatheca large, including spheroid sperm, post-vulval uterine sac (PUS) 8 to 12 µm long and gradually tapering to an elongate conoid tail with pointed tip. It was compared with relevant species of Filenchus having four incisures in the lateral fields and similar general morphology. By having a disc-like differentiation in the frontal end under the LM, it was further compared with three similar known species of Discotylenchus. The morphological comparisons with species under two aforementioned genera showed the recovered population belongs to an unknown species, described herein as Filenchus pseudodiscus n. sp. The molecular phylogenetic relationships of the new species using partial small and large subunit ribosomal RNA gene (SSU and LSU D2-D3 rDNA) sequences were reconstructed and discussed. Malenchus gilanensis, the second recovered and studied species was originally established based upon traditional criteria. An updated LSU phylogeny of the genus Malenchus by including M. gilanensis was also presented and its results were discussed.

<article-title xml:lang="en">Morphological and molecular characterization of <italic>Filenchus pseudodiscus</italic> n. sp. from east Golestan province, north Iran; with an updated phylogeny of <italic>Malenchus</italic> Andrássy, 1968 (Tylenchomorpha: Tylenchidae)

Journal of Nematology

This work is licensed under the Creative Commons Attribution 4.0 International License.

Morphological and molecular characterization of  n. sp. from east Golestan province, north Iran; with an updated phylogeny of  Andrássy, 1968 (Tylenchomorpha: Tylenchidae)

During a survey in Golestan province, north Iran, two populations belonging to the family Tylenchidae were recovered in association with Quercus sp., and a...

Morphological and molecular characterization of Filenchus pseudodiscus n. sp. from east Golestan province, north Iran; with an updated phylogeny of Malenchus Andrássy, 1968 (Tylenchomorpha: Tylenchidae)

Published Online: Aug 05, 2021

Page range: 1 - 14

DOI: https://doi.org/10.21307/jofnem-2021-069

Keywords
LSU rDNA D2-D3, Morphology, New species, Phylogeny, SSU rDNA, Taxonomy

© 2021 Parnaz Mortazavi et al., published by Sciendo.

This work is licensed under the Creative Commons Attribution 4.0 International License.

Morphological and molecular characterization of Filenchus pseudodiscus n. sp. from east Golestan province, north Iran; with an updated phylogeny of Malenchus Andrássy, 1968 (Tylenchomorpha: Tylenchidae)

Published Online: Aug 05, 2021

Page range: 1 - 14

DOI: https://doi.org/10.21307/jofnem-2021-069

KeywordsLSU rDNA D2-D3, Morphology, New species, Phylogeny, SSU rDNA, Taxonomy

© 2021 Parnaz Mortazavi et al., published by Sciendo.

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
LSU rDNA D2-D3, Morphology, New species, Phylogeny, SSU rDNA, Taxonomy