Biocomplexity Project: A Synthetic Approach to Phytotelmata Communities

Results of the Study As the data are still being analyzed, only preliminary results are presented here. We request that these data not be used for any purpose without permission and proper aknowledgment. We are currently working on publications and will send manuscripts on request. Sarracenia purpurea There was significant among-site variation in the appearance of the plant itself and in their habitats. Populations of Sarracenia purpurea in the north were more likely to be in very wet bogs or along pond margins, often in deep sphagnum, while plants in the south could be found in sandy soil in seepege bogs that could be quite dry for periods of time. Plants in the north had significantly more leaves and were shorter (as measured from the ground surface to the top of the tallest leaf). The mean leaf length did not significantly change with latitude, suggesting that the plants in the north have a more prostrate form or may be nestled down into sphagnum, decreasing their apparently height. There were no significant trends in the size of the keel or aperture. Naczi et al. (1999) had suggested that there may also be differences in the morphology of the pitcher, such as in lip width, that justify dividing Sarracenia purpurea into two species. We found no significant pattern in lip width with latitude, although the southern-most population did tend to have somewhat thicker leaf lips. We hope to further analyze these data to understand how aspects of the habitat or climate may affect morphology. The plant shape may vary in more subtle ways, such as generaly shape or color. All leaves were photographed and will be analyzed for such differences, as well as looking for specific differences among the proposed subspecies and species. Invertebrates The invertebrate species composition seems fairly constant over the 39 sites. Virtually all sites contained the major known invertebrates: the mosquito Wyeomyia smithii, the midge Metriocmenums knabi, the mite Sarraceniopus gibsoni, and the rotifer Habrotrochus rosa. This suggests interesting questions about the relative stability of this species group. In addition, 11 other invertebrate taxa were recorded (Table 1), most of which were relatively rare. At the among-pitcher scale, the presence of the four most abundant taxa (midges, mites, mosquitoes, and bdelloid rotifers) was more variable; each occurred in less than 62% of the pitchers collected. The other eleven taxa occurred in less than 10% of pitchers. Table 1. Number of sites (out of the 39) and pitchers (out of the 780) in which each invertebrate taxon occurred. Taxon Number of sites Percentage of sites Number of pitchers Percentage of pitchers Midges 38 97 480 61.5 Mites 38 97 474 60.8 Mosquitoes 37 95 461 59.1 Bdelloid rotifers 38 97 370 47.4 Flesh flies 23 59 67 8.6 Copepods 16 41 43 5.5 Loricate rotifers 12 31 23 2.9 Nematodes 8 21 15 1.9 Unknown rotifers 9 23 13 1.7 Cladocerans 8 21 10 1.3 Gastropods 3 8 3 0.4 Gastrotrichs 2 5 2 0.3 unknown Mosquitoes 2 5 2 0.3 Amphipods 1 3 1 0.1 Tardigrades 1 3 1 0.1 Protozoans In all, 50 different types of protozoa were distinguished. We are now confirming identifications of many of these species. As with the invertebrates, several types were relatively common across the 39 sites. We do not know whether these are exactly the same species across all sites or whether they are specialists in pitcher plants or just common environmental types. Many types were rare; just over half of the taxa were found only at one or two sites (Table 2). Most of the taxa were rare at the pitcher scale; only 6 of the 50 taxa occurred in more than 10% of the pitchers. Table 2: Number of sites (out of the 39) and pitchers (out of the 780) in which some of the most abundant protozoan taxon occurred Genus Number of sites Percentage of sites Number of pitchers Percentage of pitchers Bodo 39 100 402 51.5 Colpoda 37 94.9 141 18.1 Colpidium 34 87.2 100 12.8 Chrysomonas 32 82.1 149 19.1 Cyclidium 32 82.1 126 16.2 Peranema 17 43.6 32 4.1 unknown 16 41.0 44 5.6 unknown 15 38.5 88 11.3 Cryptomonas 14 35.9 25 3.2 Anisonema 13 33.3 22 2.8 Tachysoma 10 25.6 12 1.5 Paramecium 9 23.1 18 2.3 Petalomonas 9 23.1 19 2.4 Euglena 8 20.5 24 3.1 Menoidium 8 20.5 11 1.4 Bacteria We identified 30 different colony types of bacteria. Because we identified types on the basis of colony growth on agar, we cannot yet confirm species identifications across sites. We have preserved the 5-8 most abundant colony types at each site and hope to use 16S sequencing or fingerprint data to identify species at a later date. The colony types were often highly colored, a common feature of bacteria in stressed environments. Colony-type composition was more variable than that of invertebrates and protozoa; only 9 out of the 30 types occurred in more than 90% or less than 10% of sites. At the pitcher scale, however, nearly half of the taxa occurred in less than 10% of the pitchers.