Predators select for defensive adaptations, such as stings, toxins, and camouflage color patterns. Madtoms, Noturus, are diminutive catfishes with dorsal and pectoral stings. Thirteen of the 25 nominal species have serrated spines in the pectoral sting and a contrasting pigment pattern. Behavior of two saddled species, N. miurus and N. hildebrandi, and one uniformly colored species, N. leptacanthus, was investigated to test if the pigment pattern is camouflage. Saddle spacing and crypticity of the saddled species were measured against various substrates and were found to be unevenly spaced, which could be camouflage when viewed against gravel. Given substrate choices, madtoms preferred gravel during daylight conditions. In subsequent experiments, all species were given colored gravel to test color vs. texture-based substrate choice and preferred dark substrates. In the presence of a predator stimulus, madtoms preferred gravel at night and dawn. The pigment pattern likely is camouflage when viewed against gravel substrates.

Butterfly wing color patterns result from the arrangement of monochromatic scales containing chemical pigments and a delicate architecture that can cause interference or diffraction of light, generating iridescent colors. The latter mechanism is known as structural coloration and, despite its ecological importance, little is known about the molecular mechanisms underlying the development of this trait. The Southern Dogface butterfly, Zerene cesonia, exhibits sexually dimorphic development of ultraviolet wing reflectance. Males possess a UV-reflective patch on the forewing that results from nano-structures on the wing scales, which are absent in females. This dimorphism offers an excellent opportunity to explore the genetic mechanisms involved in pattern formation and cyto-structural variation. We used RNA-seq data from imaginal wing discs through late larval and pupal development to identify genes involved in the regulation of color pattern and scale structure formation. We identified candidate genes for the regulation of wing color pre-patterning and sexually-dimorphic development of wing scales. Our results provide a genomic resource for the identification and characterization of genes that participate in the regulation of wing development in pierid butterflies.

A revision and a phylogenetic analysis of the genera Zelomorpha Ashmead, 1900 and Hemichoma Enderlein, 1920 were conducted. Phylogenetic analyses used molecular and morphological data. A total of 39 sequences were obtained for COI (887 bases long) and 57 for 28S (1254 bases long). DNA sequences were aligned manually and also aligned with ClustalW (Thompson et al. 1997). Parsimony, Maximum Likelihood, and Bayesian approaches were applied to phylogenetic analyses with each gene region analyzed separately and in a combined analysis. The phylogenetic analysis analyses supported the monophyletic status of the genera Zelomorpha, as defined by Sharkey et al. (2006), and Hemichoma; they upholdseld the hypothesis that the the New World species formerly placed in Biroia belonged to Zelomorpha, and corroborated the synonomy ofgenus Dichelosus with Zelomorpha (Sarmiento and Sharkey, 2005). A total of 3,242 specimens of Hemichoma and Zelomorpha collected through the New World representing 113 species were examined. In addition to the 29 species of Zelomorpha described originally in diverse genera and now moved into the Zelomorpha, 74 new species are described. Seven new species are described for the genus Hemichoma for a total of 10 species. All species are fully redescribed. Fully illustrated keys to the species of Zelomorpha and Hemichoma are provided. The phylogenetic results based on maximum parsimony suggest that, despite the colorful nature of the sister group Hemichoma, species of Zelomorpha were nocturnal and became diurnal secondarily in one lineage. The change to diurnality is linked to a decrease in eye size, to an increase in body size, and to the emergence of colorful patterns. Palatability field tests using lizards as predators of Zelomorpha concinna, a common species with one of the more characteristic and bright color patterns, suggest that the coloration has a warning function and that this wasp is highly unpalatable. Evidence was found that the short ventrally curved ovipositor is an effective defensive structure. DISCLAIMER: The text of this dissertation does not constitute the publication of new species as defined by the International Code of Zoological Nomenclature. The newly estrablished species names in this work will be/have been recognized as valid upon their publication in a peer-reviewed journal.

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