Morphological and Molecular Study of the Fish Parasitic Crustaceans Cymothoa indica and Mothocya collettei (Isopoda: Cymothoidae), with New Distribution Records
Round 1
Reviewer 1 Report
This is a good paper with interesting findings. There are a few comments and edits in the attached pdf.
Comments for author File: 
Comments.pdf
The English language was good.
Author Response
Reviewer 1
I thank you for your thoughtful suggestions and insights. The manuscript has been re-checked and the necessary changes have been made in accordance with your suggestions. The responses to all comments have been prepared and attached herewith below. Edits made to the file have been reflected in the manuscript.
Thank you for your consideration. I look forward to hearing from you.
Sincerely,
Hiroki Fujita
This is a good paper with interesting findings. There are a few comments and edits in the attached pdf.
R: Thank you very much for your very helpful feedback, I revised the manuscript according to your suggestion.
Comments in the file
L83: This sentence is confusing. Rather move COI and 16S later on in the sentence.
R: Agreed and revised it as you indicated.
L90: Why are the molecular results given first? You methods section has the morphology first and it make sense to do morphology before the molecular identification if you are using morphological characteristics to identify the species.
R: Because C. indica can only be identified by DNA analysis, the results of DNA analysis need to be discussed first.
L90: italics
R: Agreed and revised it as you indicated.
L106: Is there a reason why they could not be included?
R: That is because there is no data on GenBank. I added the reason in this sentence.
L127: Of the cephalon I assume?
R: This is regarding cephalon; I added it to the text on cephalon.
Figure 3: This image (C) is so unclear and does not provide any information on this species. Is there a better image?
R: A photograph of the ventral view is necessary to determine the presence or absence of a brood pouch. Because the individual has already been dissected for drawing, it cannot be re-photographed. I am sorry.
L158: Why is pereopod 7 not with the other pereopods?
R: I revised it.
L177: The specimen is not juvenile because it has the characteristics. It is identified as a juvenile based on these characters
R: I revised these sentences with input from other reviewers.
L185, 190: italics
R: Agreed and revised it as you indicated.
L259: We...but it is a single author publication?
R: I replaced it “I”.
L321: Some species names in the references need italics
R: Agreed and revised it as you indicated.
L321: The citation on the website is different to this.
R: Agreed and revised it as you indicated.
Reviewer 2 Report
In the title, the specific names indica and collettei must not be capitalized.
In the Abstract, I changed “Okinawa Islands” to “Ryukyu Islands”, since neither species has been recorded anywhere between Kyushu and Taiwan before.
The abstract mentions Cymothoa indica “juveniles”, but there was only one specimen. This confusion about specimen number reappears frequently elsewhere in the text.
The Introduction says there are six stages in the life history, but only five are listed; I have tentatively added “egg/embryo” to the head of the list.
In section 2.2 (Molecular analysis), several clarifications are needed: 1) how many, and which, pereopods were sacrificed for DNA extraction? Were the extracted pereopods still usable for microscopical study and drawing? 2) Was Tris-HCl added to each tube? If so, add the word “each”. 3) Was the DNA in the supernatant or in the centrifuged pellet, and did the PCR mixture include 1 microliter of the solution or the pellet? In the third paragraph, please replace “under registration” with actual registration numbers.
There is a lot of wasted space at the bottom of pp. 3 and 5.
The drawings are very cartoon-like. If a lot of fine setation, pilosity, surface sculpturing, etc. has been omitted, the captions should say so. The drawings of pleopods and uropods could be improved by using stippling to more clearly indicate which plate-like ramus lies below the other.
Because the eyes are oriented obliquely, it is insufficient to say that their size is 0.7 times the width, and 0.4 time the length, of the cephalon. What axes of the eye are being compared with the cephalic dimensions? Please show this in Fig. 4A. The revised text may have to be adjusted accordingly.
The descriptions of the marginal setae of the uropodal rami of C. indica do not match the figures (which show apical setae as well as medial/lateral setae). The text should furthermore clarify that the medial/lateral setae are limited to the distal half or less of each margin. The text does not mention the setae on the distal corner of the peduncle.
The first paragraph of the Discussion fails to cite any of the papers about Okinawan cymothoids that were published by Williams & Bunkley-Williams around the 1990s.
The first paragraph of the Discussion says that 16S could not distinguish C. indica and C. eremita, but the Results section says (and Fig. 2 shows) that the two species involved are C. indica and C. pulchrum. C. eremita is the next more basal branch on the tree, thus distinguishable from both. I have changed the Discussion text accordingly to read C. pulchrum.
I don’t think the final paragraph of the Discussion is very useful and recommend its deletion. Cinusa is rather outside the scope of the present study. Furthermore, adding the two present specimens to an existing dataset cannot be expected to affect the main shape of the previous study’s tree. Confirmation of the earlier results concerning Cinusa is only to be expected.
Comments on the References:
1. Capitalize Database? Add the year to the access date.
2. List all the authors in full unless the journal’s instructions say not to.
5. Italicize Nerocila californica.
7. Delete the comma after Isopoda; capitalize Crustacea and Pacific.
8. Insert a space after “sp.”
11. Do not capitalize most words in the title; italicize the two scientific names.
12. Close spaces around the end-parenthesis.
18. The date 2013 should be in boldface font.
20. Italicize the two scientific names; capitalize Isopoda.
21. Spell out the journal title fully.
23. Add the DOI number.
24. Do not capitalize the final two words of the title, computing platforms.
25. Italicize Cymothoa.
27. Is this a dissertation? If so, please check the required format for dissertations.
32. Add the article number – 105 – as “pagination” after the volume number.
34. Italicize Mothocya.
40. Do not capitalize most words in the title; re-capitalize the journal title as PLoS ONE?
Comments for author File: Comments.pdf
The author has already had a commercial editing company review his MS, and the resulting text is certainly readable, but a moderate amount of additional editing is needed. Especially, the commercial editing company seems not to have understood that only one new specimen of each species was studied; inappropriate plural constructions abound. More precise and concise phraseology is also often possible. To show what might be done, I am attaching a "Track-Changes" rewrite of the parts where the greatest density of corrections/suggestions occur. The description of the second species, not treated in the attached file, requires more or less the same changes as the description of the first species. Other parts of the text and the Figure captions could also benefit from minor changes of a similar nature. Necessary typographic and other changes to the References are listed in the "Comments to Authors".
Author Response
Reviewer 2
I thank you for your thoughtful suggestions and insights. The manuscript has been re-checked and the necessary changes have been made in accordance with your suggestions. The responses to all comments have been prepared and attached herewith below. Edits made to the file have been reflected in the manuscript.
In the title, the specific names indica and collettei must not be capitalized.
R: Agreed and revised it as you indicated.
In the Abstract, I changed “Okinawa Islands” to “Ryukyu Islands”, since neither species has been recorded anywhere between Kyushu and Taiwan before.
R: Agreed and revised it as you indicated.
The abstract mentions Cymothoa indica “juveniles”, but there was only one specimen. This confusion about specimen number reappears frequently elsewhere in the text.
R: Agreed and revised it as you indicated.
The Introduction says there are six stages in the life history, but only five are listed; I have tentatively added “egg/embryo” to the head of the list.
R: I replace six with five.
In section 2.2 (Molecular analysis), several clarifications are needed: 1) how many, and which, pereopods were sacrificed for DNA extraction? Were the extracted pereopods still usable for microscopical study and drawing?
R: I noted in the manuscript that I used the right preopod 7. This is different from the one used for the drawing.
2) Was Tris-HCl added to each tube? If so, add the word “each”.
R: I added “each” in the sentence.
3) Was the DNA in the supernatant or in the centrifuged pellet, and did the PCR mixture include 1 microliter of the solution or the pellet?
R: DNA was contained in the supernatant.
In the third paragraph, please replace “under registration” with actual registration numbers.
R: Agreed and revised it as you indicated.
There is a lot of wasted space at the bottom of pp. 3 and 5.
R: Agreed and revised it as you indicated.
The drawings are very cartoon-like. If a lot of fine setation, pilosity, surface sculpturing, etc. has been omitted, the captions should say so. The drawings of pleopods and uropods could be improved by using stippling to more clearly indicate which plate-like ramus lies below the other.
R: Agreed and revised it as you indicated. I already used broken line.
Because the eyes are oriented obliquely, it is insufficient to say that their size is 0.7 times the width, and 0.4 time the length, of the cephalon. What axes of the eye are being compared with the cephalic dimensions? Please show this in Fig. 4A. The revised text may have to be adjusted accordingly.
R: The comparison was changed to eye long axis vs. cephalon length and eye short axis vs. cephalon width, respectively.
The descriptions of the marginal setae of the uropodal rami of C. indica do not match the figures (which show apical setae as well as medial/lateral setae). The text should furthermore clarify that the medial/lateral setae are limited to the distal half or less of each margin. The text does not mention the setae on the distal corner of the peduncle.
R: Agreed and revised it as you indicated.
The first paragraph of the Discussion fails to cite any of the papers about Okinawan cymothoids that were published by Williams & Bunkley-Williams around the 1990s.
R: Thank you for your suggestion. I added that reference to the discussion.
The first paragraph of the Discussion says that 16S could not distinguish C. indica and C. eremita, but the Results section says (and Fig. 2 shows) that the two species involved are C. indica and C. pulchrum. C. eremita is the next more basal branch on the tree, thus distinguishable from both. I have changed the Discussion text accordingly to read C. pulchrum.
R: I am sorry, I missed. Thank you for your editing.
I don’t think the final paragraph of the Discussion is very useful and recommend its deletion. Cinusa is rather outside the scope of the present study. Furthermore, adding the two present specimens to an existing dataset cannot be expected to affect the main shape of the previous study’s tree. Confirmation of the earlier results concerning Cinusa is only to be expected.
R: Based on the opinions of other reviewers, I decided to keep this paragraph. It also included a discussion about Elthusa.
Comments on the References:
- Capitalize Database? Add the year to the access date.
R: Agreed and revised it as you indicated.
- List all the authors in full unless the journal’s instructions say not to.
R: The reference contains nearly 100 authors. It abbreviated according to the Endnote format provided by the journal.
- Italicize Nerocila californica.
R: R: Agreed and revised it as you indicated.
- Delete the comma after Isopoda; capitalize Crustacea and Pacific.
R: Agreed and revised it as you indicated.
- Insert a space after “sp.”
R: Agreed and revised it as you indicated.
- Do not capitalize most words in the title; italicize the two scientific names.
R: Agreed and revised it as you indicated.
- Close spaces around the end-parenthesis.
R: Agreed and revised it as you indicated.
- The date 2013 should be in boldface font.
R: Agreed and revised it as you indicated.
- Italicize the two scientific names; capitalize Isopoda.
R: Agreed and revised it as you indicated.
- Spell out the journal title fully.
R: Agreed and revised it as you indicated.
- Add the DOI number.
R: Agreed and revised it as you indicated.
- Do not capitalize the final two words of the title, computing platforms.
R: Agreed and revised it as you indicated.
- Italicize Cymothoa.
R: Agreed and revised it as you indicated.
- Is this a dissertation? If so, please check the required format for dissertations.
R: Agreed and revised it as you indicated.
- Add the article number – 105 – as “pagination” after the volume number.
R: Agreed and revised it as you indicated.
- Italicize Mothocya.
R: Agreed and revised it as you indicated.
- Do not capitalize most words in the title; re-capitalize the journal title as PLoS ONE?
R: Agreed and revised it as you indicated.
Reviewer 3 Report
see attached pdf
Comments for author File: Comments.pdf
The contribution is in general interesting, though weak, because only single specimens of two species were examined. The drawings are a bit sketchy and wobbly.
Several statements are not precise and some language editing is necessary. Corrections have been added in the adjoined pdf file. Comments in the pdf file can be read with Acrobat tools, klick on the marked sections.
Concerning the position of Elthusa in the phylogenetic trees, the author should mention that the genus seems to be polyphyletic in his data. He overlooked this fact.
Author Response
Reviewer 3
I thank you for your thoughtful suggestions and insights. The manuscript has been re-checked and the necessary changes have been made in accordance with your suggestions. The responses to all comments have been prepared and attached herewith below. Edits made to the file have been reflected in the manuscript.
The contribution is in general interesting, though weak, because only single specimens of two species were examined. The drawings are a bit sketchy and wobbly.
Several statements are not precise and some language editing is necessary. Corrections have been added in the adjoined pdf file. Comments in the pdf file can be read with Acrobat tools, klick on the marked sections.
Concerning the position of Elthusa in the phylogenetic trees, the author should mention that the genus seems to be polyphyletic in his data. He overlooked this fact.
R: Thank you very much for your very helpful feedback, I revised the manuscript according to your suggestion. Particularly, I mentioned Elthusa is polyphyletic in the tree.
Comments in PDF
L44: statement is not logical. To identify hosts you do not need a phylogenetic study.
R: Agreed and revised it as you indicated.
L45: statement is too general and therefore not correct. There are many cymothoid species for which the distribution and host preferences are well known.
R: I revised the sentence to say that information is lacking about some species.
L308–310: delete: too general and trivial statement
R: I determined that this sentence is necessary as a closing. This wording was revised.
