Platythyrea pilosula - Image by April Nobile/Antweb
Yesterday, the above photograph was uploaded to Antweb's databases.  Platythyrea pilosula is the final species to be imaged for the Ants of Paraguay project, marking the end of a sporadic and meandering study that I started in 1995 as a hobby during my stint in the Peace Corps. After combining several years' worth of my field collections with the holdings at 19 entomological museums, I tallied 541 species for the country. This turns out to be too many species to keep track of in my head (I max out at about 300 or so), so I've found Antweb's ready access to Paraguayan ant images very helpful.
An unexpected result of the survey was an unusual imbalance between the number of non-native ants present in Paraguay with the number of native species that are trampy or invasive elsewhere in the world:
This is precisely the opposite pattern than that shown by most regions. Consider California. With a land area equivalent to Paraguay, the state hosts 25 non-native species and perhaps only one or two natives that have established elsewhere.
Here's something for the invasion biologists to chew on: Paraguay may be the only place in the world that is a net exporter of invasive ant species. I'm not volunteering to figure out why this is, but I do hope that having the regional ant fauna catalogued and imaged will make the job easier for those who do tackle it.
source: Wild, A. L. 2007. A Catalogue of the Ants of Paraguay (Hymenoptera: Formicidae). Zootaxa 1622: 1â55.
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Good job Alex.
You are right this is really interesting to look at it with an introduced species perspective. One thing that we can notice, and I think this is really important in the spreading of exotic species, is that Paraguay has no border on the sea, and so most of the goods that arrive come by land. I think for the spreading of exotic species, human transport and especially maritime transport had played an important role. This is different for California. Concerning, the species that come from Paraguay, several are also shared with other countries (Argentina, Brasil).
Concerning the list of species, and especially of genera, I was able to find records of Cryptomyrmex and Lachnomyrmex for Paraguay. I supposed for the Cryptomyrmex, it comes from Fernandez 2004. For the Lachnomyrmex, I could find where it come from if you are interested.
Anyway. Great Job!
Thanks Benoit! Where did you turn up the Lachnomyrmex record? I'd love to see it.
What's nice about doing the Paraguay project online is that I can update it continuously to accommodate new records and taxonomic changes. Eventually, all biodiversity work should be structured around databases instead of papers. They make much more sense that way.