On the Generic Status of Asitrichiosoma Malaise, 1939 (Hymenoptera, Cimbicidae, Cimbicinae) and Its Revision, with Description of Seven New Speciesâ€
Lars Vilhelmsen
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsReviewer’s comments on Insects-4404354
The manuscript deals with a group of cimbicid sawflies occurring in China. Seven new species are described and three redescribed. Together with a couple of additional species that the authors have apparently not examined, they are placed in the genus Asitrichiosoma, a taxon previously at most recognized at the subgenus level.
The descriptions are adequate and decently illustrated. It should be stated why the few remaining species that the authors place in Asitrichiosoma were not redescribed. On ls. 95-105 the depositories of types and additional material of previously described species are listed, but it is unclear whether the authors have examined this material or at least attempted to obtain images of them from the collections where they are deposited. I suspect that the authors have mostly focused on material from ASMN; this needs to be made explicit. Apparently, the species sampled for COI, A. anthracinum, is among the taxa left out of the taxonomic treatment, which is somewhat odd; how did the authors get access to the sequence in the first place?
The most problematic aspect of the paper is its interpretation of the molecular data. They sample 25 cimbicid terminals, including five Trichiosoma and one Asitrichiosoma spp. for COI, producing a phylogeny and comparison of genetic distances between the two aforementioned genera (Fig. 1). They then use the results as evidence for recognizing Asitrichiosoma as separate from Trichiosoma (l. 139, ls. 931-935).
I do not find this argument very compelling. In the cladistic analyses, Asitrichiosoma and Trichiosoma are retrieved as sister groups; the authors seem curiously reluctant to admit this, see ls. 929-931, referring to “relatively close phylogenetic relationships … the two may share a relatively recent common ancestor”. Because the two taxa are sister groups, there is no real evidence in a cladistic sense for either splitting or merging them, it becomes a matter of opinion. Had A. anthracinum been retrieved inside Trichisoma spp., this would have supported merging the genera; conversely, if the two taxa had been placed widely separated among cimbicines, i.e., not sister groups, this would have supported recognizing two separate genera. As it is, it is neither way.
The second line of molecular support regards genetic distance. Briefly, the distance between A. anthracinum and Trichiosoma spp. is significantly larger than within the latter, a result the authors claim “strongly indicates that the two should not be classified within the same genus-level taxon” (l. 935). Again, this is an exaggeration. Only one Asitrichiosoma sp. is sampled, so there is no test of the variation of genetic distance within the 12 species suggested to be in this genus; also, its monophyly is not tested. Besides, Trichiosoma sensu lato comprises almost 50 species including the new species described here, so the overall sampling of the clade is just over 10 %. Also, I do not think there are any widely accepted threshold for recognizing different genera based on genetic distance. Furthermore, adding molecular data for more purported Asitrichisoma spp. might lower the genetic distance between it and Trichiosoma.
The authors provide a list of diagnostic traits for Asitrichiosoma; this seems convincing enough, but it is a problem that A. anthracinum is not examined for morphology. In the Discussion, the authors point out that “mounting evidence indicated that some distantly related taxa exhibit highly convergent morphologies” (ls. 905-906) and “the limitation of morphological characters lies in the fact that when different species display similar phenotypes as a result of convergent evolution or conserved morphology, traditional methods struggle to reveal their true phylogenetic relationships” (ls. 911-914). They certainly have a point, but this also somewhat undermines their morphological diagnosis of Asitrichiosoma as a separate genus, especially given that they present no independent evidence for the monophyly of Asitrichiosoma, molecular or otherwise.
The first two paragraphs of the Discussion (ls. 901-926) is a very generic overview of the use of morphological versus molecular data in current taxonomy, culminating in a paean to the integrative taxonomy approach as the “standard paradigm in modern insect taxonomy” (l. 926). Very stirring stuff, but it does not really provide anything relevant for the data presented, given the weakness of the molecular evidence presented. To be clear, what the authors have produced is not a good example of integrative taxonomy. They provide morphological treatment of ten species with no molecular data, and a COI sequence of an eleventh species that was not included in the morphological part. While they have both morphological and molecular evidence, it cannot really be said to be integrated, given the paucity of molecular data and lack of overlap between taxa sampled for the two different data sources.
In conclusion, I do not think the paper should be published in its present form, given the overinterpretation of the molecular data as presented. The taxonomic part of the paper is solid enough and can be published on its own. I have no strong feelings about the status of Asitrichiosoma; it can be diagnosed sufficiently and there is no strong evidence against it being a separate clade for the moment. The true test of generic definitions in Cimbicinae will require a comprehensive molecular analysis (as opposed to a few COI sequences). If the authors want to include the molecular data they have obtained, they need to adopt a more realistic appraisal of what these data can actually support. It would be better to exclude molecular data for now and develop it further by obtaining more sequences of Asitrichiosoma and Trichiosoma spp. before publishing it.
Cordially yours
Comments for author File: 
Comments.pdf
Author Response
Dear Editor and Reviewers,
Thank you very much for your constructive comments and suggestions on our manuscript entitled "On the generic status of Asitrichiosoma Malaise, 1939 (Hymenoptera, Cimbicidae, Cimbicinae) and its revision, with description of seven new species" (Manuscript ID: insects-4404354). We have carefully revised the manuscript according to the comments from Reviewer 1 and the Editor. Below is our point-by-point response. All revisions in the revised manuscript are highlighted in yellow.
Best regards!
Sincerely yours,
Deng guozhu
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsIt is an integrative revision on a rare subgenus Asitrichiosoma. According to the molecular and morphological evidence, authors upgraded the position into genus and publish seven new species. It is deserved to be published.
few comments as follows,
1, Scale bars should follow one format.
2, Make a worldwide species list.
3, Polish the language.
Other comments see the rev.pdf
Comments for author File: Comments.pdf
It is an integrative revision on a rare subgenus Asitrichiosoma. According to the molecular and morphological evidence, authors upgraded the position into genus and publish seven new species. It is deserved to be published.
few comments as follows,
1, Scale bars should follow one format.
2, Make a worldwide species list.
3, Polish the language.
Other comments see the rev.pdf
Author Response
Dear Editor and Reviewers,
Thank you very much for your constructive comments and suggestions on our manuscript entitled "On the generic status of Asitrichiosoma Malaise, 1939 (Hymenoptera, Cimbicidae, Cimbicinae) and its revision, with description of seven new species" (Manuscript ID: insects-4404354). We have carefully revised the manuscript according to the comments from Reviewer 2 and the Editor. Below is our point-by-point response. All revisions in the revised manuscript are highlighted in red font.
Best regards!
Sincerely yours,
Deng guozhu
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear authors and editor,
I have looked over the revised version of the paper. I acknowledge you have addressed my recommendations, adding two more taxa and toning down the claims for the strength of the molecular evidence. I have no further comments to the paper in its latest version.
Yours sincerely
Lars Vilhelmsen
