Abstract
The Nearctic Shield-backed Katydid (Shieldbacks) genus Aglaothorax is revised. Species boundaries are delimited with molecular phylogenetics, morphology, bioacoustics, and cytogenetics. Five species are redescribed: A. diminutiva (Rentz & Birchim, 1968), A. gurneyi (Rentz & Birchim, 1968), A. longipennis (Rentz & Weissman, 1981), A. morsei (Caudell, 1907), and A. ovatus (Scudder, 1899). Eight described subspecific taxa are elevated to species rank: A. armiger Rehn & Hebard, 1920 comb. restored, A. constrictans (Rentz & Weissman, 1981) stat. rev., A. costalis (Rentz & Weissman, 1981) stat. rev., A. dactyla (Rentz & Weissman, 1981) stat. rev., A. giganteus (Rentz & Birchim, 1968) stat. rev., A. islandica (Rentz & Weissman, 1981) stat. rev., A. segnis Rehn & Hebard, 1920 comb. restored, and A. tinkhamorum (Rentz & Birchim, 1968) stat. rev. Three described subspecies are made junior subjective synonyms: A. ovatus (Scudder, 1899) = A. ovatus longicauda (Rentz & Birchim, 1968); A. dactyla (Rentz & Weissman, 1981) = A. diminutiva malibu (Rentz & Weissman, 1981); and A. islandica (Rentz & Weissman, 1981) = A. morsei santacruzae (Rentz & Weissman, 1981). Twelve new species are described: A. acrolophitus sp. nov., A. amathitis sp. nov., A. bufonoides sp. nov., A. conistylus sp. nov., A. kelainops sp. nov., A. khioneos sp. nov., A. hulodomus sp. nov., A. nesiazo sp. nov., A. oreibates sp. nov., A. poecilonotum sp. nov., A. sphenosternum sp. nov., and A. strobilion sp. nov. Evolution of songs and chromosomes, biogeography, rearing, and conservation are discussed in light of the updated and expanded systematics.
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