Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Based on a combination of somatic, cephalic, and lip-region characters, authors establish a new Desmoscolex species. The descriptions and illustrations are very good. Unfortunately, more than 100 species have been discovered in this subgenus, yet the authors only compared the described species with one closely related species, resulting in an insufficiently comprehensive discussion. Would it be possible to classify the known species within the subgenus into several groups based on differences in the structure and size of cephalic setae as well as reproductive structures, so as to provide a reference for peers.

Specific comments

1. Page 1. Keywords: Please add “Jindo Korea”. meiofauna is changed to “nematode”
2. Page 3. Please provide the specific name of the laboratory in which the type specimens were deposited.
3. Page 4. Results: Phylum Nematoda Potts, 1932 should be Phylum Nematoda Cobb, 1932

         Please see Hodda, 2022

4. It is suggested to change Figure 4 to Figure 2, Figure 8 to Figure 3.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The research is scientifically very relevant being well supported by methodological approach. The sampling effort and the number of processed specimens (19 specimens examined, including both males and females) insure the taxonomic soundness eliminating any morphological doubts (artefacts). Also, the preservation and slide-mounting followed standard protocols used in nematology (e.g. Seinhorst’s slow-dehydration technique).  Overall, the experimental design is solid for a descriptive taxonomy study. All diagnostic observations are sustained by multiple observations/measurements and images (e.g., confirmation that no spines/papillae occur in D. curuvus through both DIC and SEM across several individuals). The study brings a significant contribution to the genus Desmoscolex, a group where relatively few new species have been added in recent years. The genus (especially subgenus Desmoscolex (Desmoscolex)) has historically been considered taxonomically challenging, partly due to the small size and cryptic features of these nematodes, aspects that were clearly shown by the authors. Moreover, the ultrastructural characters mentioned by the authors are critical for species delimitation (for example, a novelty for this study is the highlighting of the lip-region architecture revealed in D. curuvus, a tuberculate membrane ring with six sectoral openings and inner fragments). The significance of the study is also regional and ecological: D. curuvus being found in the tidal flats of Korea’s west coast, a habitat the authors describe as underexplored for meiofauna. Though the manuscript is already strong, the following suggestions are relatively minor: integrate some remarks from Differential Diagnosis earlier (optional): e.g., the detailed comparison with D. spinosus  (this would immediately inform readers how the new species differs from its closest relative, without needing to jump to the discussion); ensure consistency when referring to the new species in differential context, agreement on nomenclature: for ex., one time is D. (D.) curuvus and other times just D. curuvus sp. nov. (both are fine, just be consistent after the first mention). Minor edits for clarity: A few sentences could be rephrased for maximal clarity. One example is the sentence describing the SEM sample: “Because neither conditions (opened vs. closed) were not represented in both sexes, direct comparison …, nor can the two states themselves be confidently attributed to sex”. This is scientifically correct, but the authors might consider breaking it into two sentences.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf