DNA barcoding reveals diversity of Hymenoptera and the dominance of parasitoids in a sub-arctic environment
1 Biodiversity Institute of Ontario, University of Guelph, Guelph, ON, Canada
2 School of Environmental Sciences, University of Guelph, Guelph, ON, Canada
3 Natural Resources Canada, Ottawa, ON, Canada
4 Canadian National Collection of Insects, Arachnids, and Nematodes, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
5 Royal Alberta Museum, Edmonton, AB, Canada
6 Royal Saskatchewan Museum, Regina, SK, Canada
BMC Ecology 2013, 13:2 doi:10.1186/1472-6785-13-2Published: 26 January 2013
Insect diversity typically declines with increasing latitude, but previous studies have shown conflicting latitude-richness gradients for some hymenopteran parasitoids. However, historical estimates of insect diversity and species richness can be difficult to confirm or compare, because they may be based upon dissimilar methods. As a proxy for species identification, we used DNA barcoding to identify molecular operational taxonomic units (MOTUs) for 7870 Hymenoptera specimens collected near Churchill, Manitoba, from 2004 through 2010.
We resolved 1630 MOTUs for this collection, of which 75% (1228) were ichneumonoids (Ichneumonidae + Braconidae) and 91% (1484) were parasitoids. We estimate the total number of Hymenoptera MOTUs in this region at 2624-2840.
The diversity of parasitoids in this sub-Arctic environment implies a high diversity of potential host species throughout the same range. We discuss these results in the contexts of resolving interspecific interactions that may include cryptic species, and developing reproducible methods to estimate and compare species richness across sites and between surveys, especially when morphological specialists are not available to identify every specimen.