@ARTICLE{TreeBASE2Ref9902, author = {George E. Ball and David R. Maddison}, title = {Classification and evolutionary aspects of the species of the New World genus Amblygnathus Dejean, with description of Platymetopsis, new genus, and notes about selected species of Selenophorus Dejean (Coleoptera: Carabidae: Harpalini).}, year = {1987}, keywords = {}, doi = {}, url = {http://www.jstor.org/stable/25078414}, pmid = {}, journal = {Transactions of the American Entomological Society}, volume = {113}, number = {3}, pages = {189--307}, abstract = {Descriptions and illustrations of structural features of adults, keys, and geographical distribution provide the basis for characterizing the 24 known species of the autochthonous and predominantly Neotropical genus, Amblygnathus Dejean, 1829 (type species-A. cephalotes Dejean, 1829). The 15 new species and two new subspecies are: A. interior (type locality-M?xico, state of Sinaloa, Mazatlan); A. panamensis (Panam?, Canal Zone, Ancon); A. fricki (Panam?, Canal Zone, Fort Clayton); A. woodruffi (Honduras, La Lima); A. tikal (Guatemala, Department of Del Peten, Tikal); A. whiteheadi (M?xico, Chiapas, north of Ocozocuautla); A. gilvipes gilvipes (Brazil, state of Bahia, Chapada); A.g. peruanus (Peru, Department of Huanuco, Rio Yuyapichis); A. xingu (Brazil, state of Mato Grosso, Parque Nacional Xingu); A. braziliensis (Brazil, Rio de Janeiro); A. geminatus (Surinam, Onverdacht, Billiton); A. darlingtoni (Colombia, Magdalena, Rio Frio); A. bicolor (Brazil, state of Par?, Santarem); A. gigas (Brazil, state of Mato Grosso, Vera); and A. reichardti (Brazil, state of S?o Paulo, Salesop?lis). New synonyms are the following (junior synonyms in parentheses): A. mexicanus Bates, 1882 (= Selenophorus delumbis Casey, 1914); and A. subtinctus (LeConte, 1866) (= Selenophorus angulatus Casey, 1914). Transfer of Amblygnathus obscuricornis Waterhouse, 1845 to Selenophorus Dejean, 1829 is confirmed, and A. ruficollis Putzeys, 1878 is also placed in Selenophorus. A South American species whose adults have a setose dorsal surface but resemble Amblygnathus in habitus and head structure, is described as a new species in a new monobasic genus: Platymetopsis overali (type locality-Brazil, state of Para, Tracuetua Braganca). The genus Platymetopsis may be at the base of the New World Selenophorus group of genera, i.e., sister group of the ancestral stock of Athrostictus + Selenophorus branches, or it may represent a separate stock of Selenophori in the New World. Its relationships not being clear, this genus is classified incertae sedis in the Selenophorus group of genera. Based principally on a phylogenetic interpretation of character states of the male genitalia, the species of Amblygnathus are arrayed in groups and subgroups: 1., the Middle American-North American A. iripennis group-A. iripennis subgroup (one species), A. mexicanus subgroup (one species), A. puncticollis subgroup (six species), and A. subtinctus subgroup (three species); 2., the South American A. suturalis group-A. gilvipes subgroup (one species and two subspecies); A. suturalis subgroup (three species), and A. darlingtoni subgroup (three species); and 3., the A. cephalotes group-A. corvinus subgroup (one species), and A. cephalotes subgroup (five species). Similarities in structure of the male genitalia hypothesized to be synapotypic indicate that Amblygnathus is related to a complex of species of Selenophorus, designated as the "laminate species group," on the basis of common possession of a lamina, and including the subgenus Celiamorphus Casey, 1914, the S. seriatoporus group, the S. amaroides group, and the monobasic S. ruficollis group. Using this complex as out-group, the phylogeny of the species of Amblygnathus was reconstructed, indicating that the A. iripennis group is the sister taxon of the A. suturalis + A. cephalotes groups. A numerical analysis of the re-coded data, using PAUP and MacClade computer programs, indicates that the reconstructed phylogeny based on mental analysis is only partially supported, and that there are many other equally likely reconstructions, some of which are more parsimonious. Examination of the consensus trees and one of the short trees most similar to the tree resulting from the mental analysis shows that the reasons for such re-arrangements are themselves weak, or are contradicted by additional data used in the mental analysis but not in the numerical analysis. Consequently, the mental reconstruction is used as the basis for classifying the species of Amblygnathus and for evolutionary considerations, including the geographical history of the genus. The ecological aspects of the origin of Amblygnathus are postulated to have involved development of adaptations necessary for: 1, life in wet habitats (i.e., in leaf litter, in the vicinity of swamps and marshes); and 2, eating larger or harder seeds, or other tough plant tissue, and inference based on the enlarged heads of adults, with consequent increased area for origin of larger mandibular muscles. With these modifications, the ancestral stock of Amblygnathus entered an ecological zone different from that of the laminate species of Selenophorus, whose members live in drier lowland habitats. One species, Amblygnathus interior, seems to have returned to a habitat more like that of the laminate species of Selenophorus, i.e., drier litter in forests, but in mountains rather than in lowlands. A reconstructed geographical history of Amblygnathus hypothesizes an early Tertiary vicariance event that separated in Central America the ancestor of the A. iripennis group from the South American ancestral stock of the A. suturalis + cephalotes groups. Correlation of geological events during the Tertiary Period with the reconstructed phylogeny and present geographical distribution patterns indicates that the ancestral stocks of the subgroups of the A. iripennis group were variously isolated in southeastern United States, on the Atlantic and Pacific versants of Middle America, and on what were then islands of Lower Central America. Isolation is postulated to have provided the interruption in genetic contact that was necessary to permit differentiation to occur. Following initial isolations, sympatry among the various stocks was achieved through subsequent dispersal of the species. The single Greater Antillean endemic species of Amblygnathus, A. puncticollis (Putzeys, 1878) is postulated to have reached the islands by flight of volant adults from the mainland of Nuclear Central America.} }

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