Taxacom: [iczn-list] Meier et al.'s re-analysis of the data in Sharkey et al.’s (2021) in Cladistics

[Buz Wilson]

Dear Taxacom readers

I generally lurk this list, searching for interesting tidbits to think 
about. This thread got my attention because I had previously read Meier 
et al (I get the journal) as I wanted to concur with points made by 
David Campbell. I was horrified to see that Zookeys, which I assumed 
would be stronger on morphological systematics and the needs of the 
ICZN, had published this paper. When I was the scientific editor for a 
Museum journal, I would have sent similar papers back to the authors 
without bothering to request referee reports (I did on one occasion). I 
am not, however, against using molecular data for systematics.

I was interested to read David Campbell's <pleuronaia at gmail.com> post on 
this subject.
[abridged]
"At least in vertebrates this gene and the mitochondria in general is 
affected by introgression. Species boundaries are unfortunately not as 
clean as we would hope. I would imagine the same may be true of many 
invertebrate taxa and even plants."

Introgression certainly occurs in aquatic groundwater-dependent isopod 
crustaceans from our own data. I studied a flock of 30 species of 
Phreatoicidean isopods from Australia's northern territory (Kakadu and 
Arnhemland) and was able to separate them using morphological analysis. 
We also collected mtDNA from practically all species but I was confused 
by one of the species showing up as with the same genetics as another 
species (we completed the molecular analysis before I finished the 
monograph). This finding was not an accident because we collected data 
on as many as 5-6 specimens from each putative species. These isopods 
subsist during the dry season in highly compact populations and 
sequences for individuals varied only by 0-3 bases (panmixis assumed). 
The two species are readily identifiable morphologically (I provide a 
key to the species) but they have identical COI and 16S sequences, which 
is evidence that their entire mtGenome may also be identical (hopefully 
someday someone will check this). If you want to see our results, please 
see our recent monograph: Wilson GDF, Humphrey CL. 2020. The 
/Eophreatoicus/ Nicholls, 1926 species flock from Kakadu and Arnhem 
Land, with a description of a new genus of Amphisopidae (Crustacea : 
Isopoda : Phreatoicidea) Zootaxa 4854: 1-303. Zootaxa made a figure 
errata but I can provide a revised (unofficial) version if anyone is 
interested. The earlier molecular analysis: Wilson, G.D.F., Humphrey, 
C.L., Colgan, D.J., Gray, K.-A. & Johnson, R.N. (2009) 
Monsoon-influenced speciation patterns in a species flock 
of/Eophreatoicus/ Nicholls (Isopoda; Crustacea). Molecular Phylogenetics 
and Evolution, 51, 349–364. https://nam10.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdoi.org%2F10.1016%2Fj.ympev.2009.02.001&data=05%7C01%7Ctaxacom%40lists.ku.edu%7Cc029e1f0013a46c7088608da22d84add%7C3c176536afe643f5b96636feabbe3c1a%7C0%7C0%7C637860609629159000%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=ztKeMMAtycOHRXAJFd8p44OO%2BUTkA7NQncTzbPg5AkA%3D&reserved=0. 
The raw molecular data with updated species names and locations can be 
found on GenBank.

David Campbell again:
"Symbionts can be a problem"
Symbionts are known in isopods and may be behind the selective advantage 
shown by particular mitochondria in the /Eophreatoicus/ populations 
(another thing that I wish someone would check out).

Best wishes

Buz
-- 

George D.F. (Buz) Wilson, Ph.D.
Saugatuck Natural History Laboratory, LLC
website:https://nam10.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.snhlab.com%2F&data=05%7C01%7Ctaxacom%40lists.ku.edu%7Cc029e1f0013a46c7088608da22d84add%7C3c176536afe643f5b96636feabbe3c1a%7C0%7C0%7C637860609629159000%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=EbcJ13pBo61Wc%2BQNx2myYruZRbHOu2JiB2ULkkim6ug%3D&reserved=0
publications:https://nam10.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.researchgate.net%2Fprofile%2FGeorge-Wilson-12&data=05%7C01%7Ctaxacom%40lists.ku.edu%7Cc029e1f0013a46c7088608da22d84add%7C3c176536afe643f5b96636feabbe3c1a%7C0%7C0%7C637860609629159000%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=TCET0ncOm%2BZSIOw3sfpklsKDZQtJ5KGMGJOjf0ujoqw%3D&reserved=0
email:gdfw at SNHLab.com