In this study, we sampled aquatic snails for the presence of hairworm cysts from 46 streams in Payne County, Oklahoma. Gordiid cysts were found at 70 % (32/46) of sites examined. Based on cyst morphology, we were able to identify three morphological types of gordiid cysts, including Paragordius, Gordius, and Chordodes/Neochordodes. Using our gordiid cyst presence data in conjunction with environmental variables, we developed an ecological niche model using Maxent to identify areas suitable for snail infections with gordiids. The model successfully predicted all presence localities of gordiid cysts in snails over a geographic area of 1,810 km 2 . We used this information, along with arthropod host infections and crowdsourcing, citizen scientists sampling for adult free-living worms during peak emergent times in areas predicted suitable by the model, to document Paragordius varius, Chordodes morgani, and a new species of gordiid (Gordius n. sp.). To our knowledge, this is the first ecological niche model attempted on such a narrow geographic scale (county level) that recovered known locations successfully. We provide new scanning electron micrographs and molecular data for these species. Our field data and ecological niche model clearly indicate that gordiid cysts are easy to detect in the environment and together these sampling techniques can be useful in discovering new species of gordiids, even in relatively well sampled areas for these cryptic parasites.

Hairworms infect terrestrial arthropods and are 1 of the most understudied groups of parasites. Recently, life cycles of 2 gordiids (Paragordius varius and Paragordius obamai) have been domesticated in the laboratory. We tested the viability of laboratory reared and post-frozen larval and cyst stages of the North American gordiid, P. varius , frozen at -80 C for 7 mo, and the viability of field collected and post-frozen cysts of the African (P. obamai) and North American ( P. varius ) gordiid frozen at -20 C for 2 mo. All snails exposed to post-frozen or control P. varius larvae became infected with cysts, and there was no significant difference in prevalence or mean intensity of cysts among control or experimental snail groups. As with larvae, no significant differences were observed in prevalence or mean intensity of emerging worms from crickets infected with post-frozen or control P. obamai or P. varius cysts. All female P. obamai and P. varius worms from control and post-frozen cyst infections laid eggs and larvae hatched from some of these eggs. Survival and cyst formation of P. varius larvae exposed to different combinations of drying and/or freezing temperatures indicated that gordiid larvae have the ability to survive drying and freezing, but survival significantly increases during freezing at lower temperatures. The major contribution of our study is the demonstration that gordiid larval and cyst stages can survive freezing temperatures to infect and develop in the next host.

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Previous studies on Gyrinicola batrachiensis indicate that these pinworms have distinct reproductive strategies dependent on the development time to metamorphosis of their anuran tadpole hosts. In tadpoles of amphibian species with short developmental periods (a few weeks), female nematodes reproduce parthenogenetically, and only produce thick-shelled eggs used as transmission agents from tadpole to tadpole. In contrast, nematodes in tadpoles with longer larval developmental periods (months to years) reproduce by haplodiploidy, and females produce thick-shelled as well as autoinfective thin-shelled eggs. However, recent investigations on the haplodiploidy strain of G. batrachiensis indicate that plasticity exists in the ability of these nematodes to produce thin-shelled autoinfective eggs when these nematodes infect tadpoles of co-occurring amphibian species. Yet, little information is available on the potential mechanism for this reproductive plasticity because few co-occurring amphibian species have been examined for the reproductive strategies of these nematodes. Therefore, our goals were to document field host specificity and reproductive strategies of nematode populations in tadpoles of five co-occurring amphibian species that varied in their larval developmental periods. Additionally, we evaluated adult worm morphology from each infected amphibian species to assess any differences in worm development and reproductive strategy of pinworm populations in different amphibian species. Of the five amphibian species examined, four were infected with the haplodiploid strain of G. batrachiensis. Prevalence of G. batrachiensis ranged from a high of 83% in Acris blandchardi to a low of 15% in Pseudacris clarkii; whereas mean intensity was highest for Rana sphenocephala (10 ± 10.36) and lowest for Hyla chrysoscelis (3.23 ± 3.35). Prevalence appeared to be controlled by tadpole ecology and life history, while mean intensity appeared to be controlled by tadpole physiology and worm reproductive strategy, but not necessarily the developmental period of each anuran species. G. batrachiensis observed in long developing tadpoles of R. sphenocephala had high mean intensities and conformed to the haplodiploidy reproductive strategy with both male and female worms being present, and females produced thick-shelled and thin-shelled eggs. In contrast, tadpoles of A. blanchardi, H. chrysoscelis, and P. clarkii, which varied in their developmental times from long to short, had relatively low mean intensities and contained both male and female G. batrachiensis. However, female worms only produced thick-shelled eggs in these hosts. Importantly, morphological differences existed among female worms recovered from R. sphenocephala and female worms recovered from A. blanchardi tadpoles with long developmental periods. These data strongly suggest that when the haplodiploidy strain of G. batrachiensis is shared by tadpoles of different amphibian species, species-specific differences in interactions between these nematodes and their developme...

The Audio Arts and Acoustics department at Columbia College in Chicago acquired a new building in 2003. The facility, a former bank, contained an old steel and concrete vault that was converted to a reverberation chamber. The acoustic properties of the space, including reverberation time, modal density, and early reflection maps were analyzed and compared to a computer model. Reflectograms were predicted at various locations and compared to test data acquired with Time Delay Spectrometry (TDS). Polar Energy Time (PET) techniques were also used to identify the location of a single 4×4 sample of foam absorber and the results of the test were compared to the predicted value from the computer model. The results of the tests show that, under its current configuration, the room is usable as a reverberation chamber down to 300 Hz, and that the computer model was able to accurately predict the results from the PET methodology.