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The Hawaiian Islands have arisen in isolation in the middle of the Pacific Ocean due to volcanism unleashed by interaction of mantle-deep thermal plumes with the overlying Pacific Plate (MONTELLI et al. 2004, ABOUCHAMI et al. 2005). This volcano “factory” has produced a consistently present string of islands increasing in age from the current Big Island of Hawaii (500,000 years old) northwestwardly to the island of Kure, estimated to be 28-30 million years old (CARSON & CLAGUE 1995). Successively colonizing and proliferating on these islands since Miocene time (LIEBHERR 2005), are beetles classified in the carabid beetle genus Blackburnia SHARP, 1878 (LIEBHERR & ZIMMERMAN 2000). The 132 known Blackburnia species are arrayed in four successive adelphotaxa. The monotypic subgenus Protocaccus LIEBHERR & ZIMMERMAN, 2000, adelphotaxon to the rest of the radiation, is represented by B. mandibularis LIEBHERR, 2000 of Kauai. The next-diverging clade is classified as subgenus Colpocaccus SHARP, 1903, and is composed of four flightcapable species. The last two adelphotaxa are the nominate subgenus Blackburnia and subgenus Metromenus SHARP, 1884. The former includes 52 species, and is based on a ground-plan ancestor that was capable of dispersal by winged flight. This clade exhibits the greatest anagenetic diversification of all four clades, with various subgroups exhibiting extensive modifications of the external cuticle, including thickened, ridged, and variously shaped pronota and elytra, as well as elongate legs, and extensive specializations of the male and female genitalia (LIEBHERR & ZIMMERMAN 1998, 2000). Taxa exhibiting cuticular modifications are all brachypterous, suggesting that loss of metathoracic wings was a requisite precursor to modification of body armature. All 75 species of subgenus Metromenus are characterized by brachyptery. These also exhibit various body forms however the member taxa are never characterized by the thickened cuticle and associated modifications seen among taxa of sg. Blackburnia. Monophyly of the latter three subgenera was corroborated using molecular sequence data (CRYAN et al. 2001), though basal relationships of the three clades were resolved so that Colpocaccus and Metromenus were construed as adelphotaxa. In this study, morphological characters, and ecological and genetic characteristics of the various clades compared. These comparisons illustrate the coordinated diversification of ecological and genetic traits, and how these are associated with different levels of speciation. These traits are then put in the context of species endangerment, assessed using biotic survey data started in the 19th Century, and continuing during present-day efforts to completely describe and characterize the Blackburnia fauna.