Two New Benthic Diatoms of the Genus Achnanthidium (Bacillariophyceae) from the Hangang River, Korea

Round 1

Reviewer 1 Report

It is a very interesting work, describing  new species of Achnanthidium genus.

Introduction:

• Figs 1-15 should be moved in Results section, it is description of A. ovalis

Material and Methods:

• The isolation of diatom from environmental samples, should be better explained.  Authors obtained mono specific culture, how did  they assess it?

Results: 

this section for me is fine.

Discussion

• Table 7 is out of page.
• Section 4.4. title reffered to three species but only two are described. A.minutissimum (if it is the third species) has been already described in many papers, and it is not one of the objectives of this paper.
• Section 4.4. Authors referred to Land Use, did they asses it? if yes details must included in material and methods and in results. If no, please cite the source of information. 

 

Author Response

# Reviewer 1

 

It is a very interesting work, describing new species of Achnanthidium genus.

 

Introduction:

 

Figs 1-15 should be moved in Results section, it is description of A. ovalis

Response: The related figures have been moved in Results section (Fig. 2).

 

Material and Methods:

The isolation of diatom from environmental samples, should be better explained. Authors obtained mono specific culture, how did they assess it?

Response: The isolation and culture processes have been explained in M&M: “Single diatom cells were isolated using a Pasteur pipette (Hilgenberg GmbH, Germany) and the capillary method [37] under an Olympus CKX41 inverted microscope (Olympus, Tokyo, Japan). Cells were isolated and cultured in 96-well cell plates, and each well contained 160 μl of Diatom Medium (DM) [38]. After 10–14 days of isolation, diatoms reached the exponential growth stage [39]. The cells that grew and had a healthy aspect were transferred into 24-well cell plates with 1 ml of DM. Again, after 10–14 days, the cells that were in good condition were transferred to 50 cm3 culture flasks with 20 ml of DM. To maintain healthy cells, each strain was sub-cultured at 40-day intervals. All the strains were cultured at 20°C, irradiance of c. 50 μmol quanta m-2 s-1, and a 12:12 h light: dark cycle with cool white fluorescent light.”

 

Results: this section for me is fine.

Discussion

Table 7 is out of page.

Response: We have re-edited this page.

 

Section 4.4. title reffered to three species but only two are described. A.minutissimum (if it is the third species) has been already described in many papers, and it is not one of the objectives of this paper.

Response: That has been corrected.

 

Section 4.4. Authors referred to Land Use, did they asses it? if yes details must included in material and methods and in results. If no, please cite the source of information.

Response: The source of information has been cited.

Reviewer 2 Report

Reviewer’s comments on the manuscript

Two new benthic diatoms of the genus Achnanthidium (Bacillariophyceae) from the Hangang River, Korea

Manuscript ID: diversity-862117

The manuscript fits the aims and scope of the Diversity MDPI. The paper is quite well written. The introduction is clear and contains the most important information about the genus Achnanthidium. A fragment of materials and methods contains sufficiently accurate information on the studies carried out. Descriptions of the two new species are properly written, as well as sufficiently compared with similar species in the discussion.

The main problem concerns proposed names that are incompatible with Latin grammar. Achnanthidium is neuter, so the epithet should be changed accordingly. I suggest changing Achnanthidium ovalis to A. ovale or A. oviforme. The name A. ovatum cannot be used, because such a species already exists. The same problem applies to Achnanthidium cavitata - it should be A. cavitatum.

A map with a sampling points is missing.

Apart from the above remarks, the text contained a few errors, mainly typos and cited literature.

Figs 1–15 should be in the Results section, not in the Introduction.

Line 75 Figs not Figs. (no dot after s). Also line 183 and many others lines.

Line 126 “This process was performed at least four times” information repeated from line 125 – “…the samples were wasched four times…”. Unless the samples have been rinsed up to 16 times, it can stay as it is.

Line 185 location; 30–35 in um in the center, …

Line 185 and 186 The number of striae on the primary side is higher than on the secondary side …

Line 188 … but radiate very slightly…

Line 191 and 192 The number of areolae on the mantle not corresponding to the areolae on the valve face is 3–5…. Without this annotation this sentence is not true.

Line 198 Central raphe endings deflect …

Line 216 Fig. 22 – In the internal view not on the …

Line 242 The axial area is broad … – the same information repeated from lines 240 and 241.

Line 245 and 246 of striae … on the primary side … than on the secondary side …

Line 265 (Figs 58, 59 – solid arrows).

Line 267 (Fig. 59, dotted arrow) – lack of dotted arrow.

Table 7 – at the end there should be sources adequate to Table 6, also, replace all hyphens (-) between numbers with dashes (–).

 

Literature missed in the References:

Medlin & Kaczmarska 2004

Guo et al. 2015

Ki et al. 2005

Kumar et al. 2016

Stamatakis 2014

Ronquist et al. 2012

Kobayasi 1986 –  Kobayasi et al. 1986?

 

References – lack in the text:

Bukhtiarova 2007, 2008

Bukhtiarova and Round 1996

Hwangs et al. 2011

Joh 2012

Kutzing 1833, 1844

Lai et al. 2016

Lobo et al. 1955

Luttenton & Rada 1986

Marquadt et al. 2017

Monnier et al. 2007

Potapova 2012

Tan et al. 2014

Wojtal et al. 2011

I have no other objections to the reviewd paper and am thus glad to recommend the paper for publication in the Diversity MDPI once indicated issues have been addressed, after a major revision of the manuscript.

Author Response

# Reviewer 2

 

Reviewer’s comments on the manuscript

Two new benthic diatoms of the genus Achnanthidium (Bacillariophyceae) from the Hangang River, Korea

Manuscript ID: diversity-862117

The manuscript fits the aims and scope of the Diversity MDPI. The paper is quite well written. The introduction is clear and contains the most important information about the genus Achnanthidium. A fragment of materials and methods contains sufficiently accurate information on the studies carried out. Descriptions of the two new species are properly written, as well as sufficiently compared with similar species in the discussion.

 

The main problem concerns proposed names that are incompatible with Latin grammar. Achnanthidium is neuter, so the epithet should be changed accordingly. I suggest changing Achnanthidium ovalis to A. ovale or A. oviforme. The name A. ovatum cannot be used, because such a species already exists. The same problem applies to Achnanthidium cavitata - it should be A. cavitatum.

Response: Thanks for your suggestion. We have changed the new taxa name as A. ovale and A. cavitatum, according to the reviewer’s comment.

 

A map with a sampling points is missing.

Response: We add a map with the sampling points. Please see the Fig. 1.

 

Apart from the above remarks, the text contained a few errors, mainly typos and cited literature.

Figs 2–15 should be in the Results section, not in the Introduction.

Response: The related figures have been moved in Results section (Fig. 2).

 

Line 75 Figs not Figs. (no dot after s). Also line 183 and many others lines.

Response: Corrected, according to the reviewer’s comment.

 

Line 126 “This process was performed at least four times” information repeated from line 125 – “…the samples were wasched four times…”. Unless the samples have been rinsed up to 16 times, it can stay as it is.

Response: Corrected, according to the reviewer’s comment.

 

Line 185 location; 30–35 in um in the center, …

Response: Corrected, according to the reviewer’s comment.

 

Line 185 and 186 The number of striae on the primary side is higher than on the secondary side …

Response: Corrected, according to the reviewer’s comment.

 

Line 188 … but radiate very slightly…

Response: Corrected, according to the reviewer’s comment.

 

Line 191 and 192 The number of areolae on the mantle not corresponding to the areolae on the valve face is 3–5…. Without this annotation this sentence is not true.

Response: To avoid confusion, this sentence has been removed.

 

Line 198 Central raphe endings deflect …

Response: Corrected according to the reviewer’s comment.

 

Line 216 Fig. 22 – In the internal view not on the …

Response: Corrected, according to the reviewer’s comment.

 

Line 242 The axial area is broad … – the same information repeated from lines 240 and 241.

Response: Corrected, according to the reviewer’s comment.

 

Line 245 and 246 of striae … on the primary side … than on the secondary side …

Response: Corrected, according to the reviewer’s comment.

 

Line 265 (Figs 58, 59 – solid arrows).

Response: Corrected, according to the reviewer’s comment.

 

Line 267 (Fig. 59, dotted arrow) – lack of dotted arrow.

Response: Corrected, according to the reviewer’s comment.

 

Table 7 – at the end there should be sources adequate to Table 6, also, replace all hyphens (-) between numbers with dashes (–).

Response: We have revised the tables.

 

Literature missed in the References:

Medlin & Kaczmarska 2004

Guo et al. 2015

Ki et al. 2005

Kumar et al. 2016

Stamatakis 2014

Ronquist et al. 2012

Kobayasi 1986 –  Kobayasi et al. 1986?

 

References – lack in the text:

Bukhtiarova 2007, 2008

Bukhtiarova and Round 1996

Hwangs et al. 2011

Joh 2012

Kutzing 1833, 1844

Lai et al. 2016

Lobo et al. 1955

Luttenton & Rada 1986

Marquadt et al. 2017

Monnier et al. 2007

Potapova 2012

Tan et al. 2014

Wojtal et al. 2011

Response: Corrected, according to the reviewer’s comment.

 

I have no other objections to the reviewed paper and am thus glad to recommend the paper for publication in the Diversity MDPI once indicated issues have been addressed, after a major revision of the manuscript.

 

Dear # Reviewer 2

We appreciate your careful evaluation of our manuscript and hope that this revision meets your expectations. If you have any questions, please do not hesitate to contact us.

Sincerely,

Baik-Ho Kim, on behalf of all co-authors

Round 2

Reviewer 1 Report

No more comments or suggestion

Author Response

Again thank you very much for your valuable comments.

Reviewer 2 Report

Dear Authors and Editors,

At the end of the Table 7 (last line) there should be sources like in the Table 6. Please, add them. I have no other comments.

Author Response

At the end of the Table 7 (last line) there should be sources like in the Table 6. Please, add them. I have no other comments.

 

Response: According to the reviewer's recommendation, I added the related source.