Karima Mahmoud Azzam*

Plant Protection Research Institute, Agricultural Research Center, Dokki, Giza, Egypt

*Corresponding Author: Karima Mahmoud Azzam, Plant Protection Research Institute, Agricultural Research Center, Dokki, Giza, Egypt

Received: April 14, 2025; Published: April 23, 2025

Abstract

Currently, there are known to be 21-23 species of Phasmarhabditis nematodes in existence. This research focused on characterizing the newly discovered species, Phasmarhabditis eobaniae n. sp., by comparing it morphologically and phylogenetically with previously identified Egyptian species like Phasmarhabditis tawfiki, Phasmarhabditis eagyptiaca, and other Phasmarhabditis species worldwide.

Nematode-infected and healthy snails were collected from Greater Cairo, Egypt. P. eobaniae n. sp.'s 18S ribosomal (18S rRNA) and (ITS) rDNA gene sequences were acquired. The nematodes were photographed, illustrated, and morphological data were measured. The three species of Phasmarhabditis from Egypt are compared morphologically and molecularly.

P. eobaniae n. sp. represent the fifth species in Africa and the third new species identified in Egypt, following P. tawfiki and P. eagyptiaca. Morphological features indicate a close relationship between the new species, P. eobaniae n. sp. and existing Phasmarhabditis species, particularly P. tawfiki, Phasmarhabditis neopapillosa, and Phasmarhabditis hermaphrodita. P. eobaniae n. sp. is closely associated with Phasmarhabditis papillosa and Phasmarhabditis apuliae, according to phylogenetic analysis of the (ITS) rDNA genes. It exhibits genrtic similarty to P. hermaphrodita based on SSU rDNA genes

The new nematode species demonestrates a significant capability to control all infected terrestrial snails and slugs, as well as 80 to 90% of aquatic snails and 80% of insect pupae and larvae. Results indicated that this newly identified nematode, Phasmarhabditis eobaniae n. sp., may potentially represent a novel addition to the Phasmarhabditis genus.

It shows promise as a biocontrol agent against gastropod pests.

Keywords: Morphology; Phynology; Snail Parasitic Nematodes; Genetic Sequencing; Biocontrol Agent

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Citation

Citation: Karima Mahmoud Azzam. “Phasmarhabditis eobaniae n. sp. (Rhabditidae) a New Snail Parasitic Nematode from Egypt with Comparison with Two Previous Egyptian Species". Acta Scientific Agriculture 9.5 (2025): 34-48.

Copyright

Copyright: © 2025 Karima Mahmoud Azzam. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.