I’ve been mentioning in this blog several unrecognized species which we have been finding in the fauna of Bembidiina in America north of México. By “unrecognized” I mean both undescribed species (those without a name), and species that have already been described, but that are currently and incorrectly considered in the literature to be a synonym of another species.
For my amusement, I decided to tally up how many species we now know about that are unrecognized in the literature, and I present the following list. The number of unrecognized species in the genus or subgenus or species group is listed in parentheses. A “+” after the number means we have hints of additional species, and ++ means that there are surely many more species, but we haven’t worked as much on that group yet and so we don’t understand how many more there are. I have not included the genus Amerizus, as Dave Kavanaugh is working on that group and is more familiar with it.
This list will continue to grow as we focus on various groups, but for now it gives a sense that we already know of a lot of undocumented species. For context, I should mentioned that there are about 250 recognized species in Canada and the continental USA.
Unrecognized species of Bembidiina (excluding Amerizus) in Canada and the continental USA
- Lionepha (2+)
- Bembidion (40++)
Subgenera of Bembidion:- Lindrochthus (1+)
- Furcacampa (2+)
- Notaphus (5++)
- Trepanedoris (2++)
- Ocydromus (1)
- Peryphus (2)
- “Nearctic Clade” (5+)
- Hydriomicrus (1)
- Plataphus (16+)
- breve group (4+)
- arcticum group (1)
- kuprianovi group (2)
- gebleri group (2+)
- prasinum (i.e., rusticum/sulcipenne/hyperboraeorum) group (1+)
- curtulatum group (4)
- planiusculum group (2)
- Hydrium (1)
- Trechonepha (1)
- Liocosmius (3+)
This totals to 42 unrecognized species. Immediately evident is the unrecognized diversity within the subgenus Plataphus; at least 16 species unrecognized, and there are likely more. This high number is partly because we have done a lot of DNA sequencing on that group. It would not surprise me if subgenus Notaphus might rival that once we study them more. Subgenus Trepanedoris might not hold as many new ones, but it clearly has quite a few. Subgenus Hirmoplataphus is very complex, and may have many undetected species.
Update: see my follow-up post about showing the geographic distribution of these species.
David Maddison
The Subulate Palpomere 
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