We report Ptycholaimellus ocellatus Huang and Wang, 2011, a free-living marine nematode of the family Chromadoridae Filipjev, 1917, as a newly recorded species in Korea. The specimen was collected from intertidal sediment habitats along the southern coast of Korea. Ptycholaimellus ocellatus is characterized by a distinct set of morphological features, including an abruptly tapered cervical region, the presence of ocelli, a transversely striated cuticle with lateral differentiation marked by two prominent longitudinal rows of dots, a large ampulla within a voluminous ventral gland, and two pharyngeal bulbs. This study provides the first taxonomic report of the genus Ptycholaimellus in Korean waters with differential interference contrast (DIC) and scanning electron microscopy (SEM) micrographs.

Abstract
1. INTRODUCTION
2. MATERIALS AND METHODS
    2.1. Sample collection and preparation
    2.2. Morphological analysis
    2.3. Scanning Electron Microscopy (SEM) imaging
3. SYSTEMATIC ACCOUNTS
CRediT authorship contribution statement
Declaration of Competing Interest
ACKNOWLEDGEMENTS
REFERENCES

• Hyo Jin Lee(East Sea Environment Research Center, Korea Institute of Ocean Science & Technology (KIOST), Uljin 36315, Republic of Korea)
• Heegab Lee(East Sea Environment Research Center, Korea Institute of Ocean Science & Technology (KIOST), Uljin 36315, Republic of Korea)
• Hyun Soo Rho(East Sea Environment Research Center, Korea Institute of Ocean Science & Technology (KIOST), Uljin 36315, Republic of Korea) Corresponding author