Publications

iridoid glycosides in the nectar ofcatalpa speciosa are unpalatable to nectar thieves.	the floral nectar ofcatalpa speciosa has a chemical mechanism that limits thievery. a bioassay employing sphingid larvae,ceratomia catalpae, shows that catalpa iridoid glycosides are present in the floral nectar. when potential nectar thieves are fed nectar, a sucrose solution of identical concentration, or a sucrose solution plus 0.4% catalpol and 0.4% catalposide (catalpa iridoids), the thieves drink significantly more of the pure sucrose solution than either of the other two sugar sources. th ...	1982	24415339
hostplant suitability and defensive chemistry of the catalpa sphinx, ceratomia catalpae.	the growth and survival of the catalpa sphinx, ceratomia catalpae (sphingidae), were measured on five different species of catalpa: c. bignonioides, c. bungeii, c. fargeseii, c. ovata, and c. speciosa. larval growth varied significantly among these host plant species; however, survival did not differ. quantification of the iridoid glycoside content of larvae, pupae, adults, larval frass, and leaves of the larval host plant, c. bignonioides, by gas chromatography showed that leaves contained both ...	2003	14682517
catalpa bignonioides alters extrafloral nectar production after herbivory and attracts ant bodyguards.	inducible anti-herbivore defenses are found within many plant taxa, but there are fewer examples of inducible indirect defenses that incorporate the third trophic level. this study links caterpillar foraging, herbivore-induced changes in extrafloral nectar production, and the attraction of ants to vulnerable leaves and plants. catalpa bignonioides walter (bignoniaceae) uses extrafloral nectar to attract ant (forelius pruinosus(roger)) bodyguards in response to ceratomia catalpae (boisduval)(lepi ...	2003	12647162
caterpillar chemical defense and parasitoid success: cotesia congregata parasitism of ceratomia catalpae.	sequestration of plant compounds by herbivorous insects as a defense against predators is well documented; however, few studies have examined the effectiveness of sequestration as a defense against parasitoids. one assumption of the "nasty host" hypothesis is that sequestration of plant defense compounds is deleterious to parasitoid development. we tested this hypothesis with larvae of the sequestering sphingid ceratomia catalpae, which is heavily parasitized by the endoparasitoid cotesia congre ...	2010	20683647
chemical defense across three trophic levels: catalpa bignonioides, the caterpillar ceratomia catalpae, and its endoparasitoid cotesia congregata.	plant secondary chemistry can vary among plant tissues, individuals, and populations, and this variation has population-level consequences for upper trophic levels. in this study, we examined the multi-trophic consequences of variation in iridoid glycosides, which are a component of plant defense against generalist herbivores and also contribute to the unpalatability of sequestering herbivores to both vertebrate and invertebrate predators. several populations of catalpa bignonioides were located ...	2011	21948221
incompatibility between plant-derived defensive chemistry and immune response of two sphingid herbivores.	herbivorous insects use several different defenses against predators and parasites, and tradeoffs among defensive traits may occur if these traits are energetically demanding. chemical defense and immune response potentially can interact, and both can be influenced by host plant chemistry. two closely related caterpillars in the lepidopteran family sphingidae are both attacked by the same specialist endoparasitoid species but have mostly non-overlapping host plant ranges that differ in secondary ...	2015	25516226