A new actinolaim, Egtitus invaginatus n. sp. (Nematoda: Actinolaimidae) from South Korea

Abraham Okki Mwamula; Chang-hwan Bae; Yi Seul Kim; Young Ho Kim; Yeong-Don Lee; Dong Woon Lee

doi:10.2478/jofnem-2026-0012

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A new actinolaim, Egtitus invaginatus n. sp. (Nematoda: Actinolaimidae) from South Korea

Journal of Nematology

Volume 58 (2026): Issue 1 (February 2026)

By: Abraham Okki Mwamula, Chang-hwan Bae, Yi Seul Kim, Young Ho Kim, Yeong-Don Lee and Dong Woon Lee

Open Access

|May 2026

Abstract

Egtitus invaginatus n. sp. isolated from litter soils sampled around a dead black pine was characterized using morphometrics and DNA barcodes. Egtitus invaginatus n. sp. is characterized by a medium sized body 1.67–2.12 mm long, lip region expanded, 2.1–2.5 times as wide as high, anteriorly truncate, with rounded to angular sides, offset by a depression, odontostyle 19.0–21.0 μm long or as long as the lip region diameter, pars refringens vaginae with two irregularly ovoid to D-shaped pieces, vulva flush with body contour in lateral view, a transverse slit in ventral view, vulva opening equatorial to slightly post-equatorial; one to three ventral cleft-like invaginations present at 4.0–6.0 μm posterior to anal opening, forming papilla-like outgrowth, tail straight or slightly curved ventrad, 12.5–17.5 times anal body diameter; spicules 46.5 μm long, seven spaced ventromedian supplements and male tail conoid to broadly rounded. The phylogenetic relationships among species were reconstructed using 18S-rRNA and 28S-rRNA gene sequences. The two phylogenies showed that E. invaginatus n. sp. is genetically similar to the only gene sequences of the genus available in GenBank database.

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Articles in this issue

DOI: https://doi.org/10.2478/jofnem-2026-0012 | Journal eISSN: 2640-396X | Journal ISSN: 0022-300X

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Language: English

Page range: 137 - 149

Submitted on: Jan 13, 2026

Accepted on: Mar 13, 2026

Published on: May 6, 2026

Published by: Society of Nematologists, Inc.

In partnership with: Paradigm Publishing Services

Publication frequency: 1 issue per year

Keywords:

Actinolaimidae,

Egtitus,

Molecular characterization,

Related subjects:

© 2026 Abraham Okki Mwamula, Chang-hwan Bae, Yi Seul Kim, Young Ho Kim, Yeong-Don Lee, Dong Woon Lee, published by Society of Nematologists, Inc.
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Volume 58 (2026): Issue 1 (February 2026)