CLADISTIC-ANALYSIS, PHYLOGENY AND BIOGEOGRAPHY OF THE HAWAIIAN PLATYNINI (COLEOPTERA, CARABIDAE)

The 128 known native Hawaiian species of the tribe Platynini are analy sed cladistically. Cladistic analysis is based on 206 unit-coded morph ological characters, and also includes forty-one outgroup taxa from ar ound the Pacific Rim. Strict consensus of the multiple equally parsimo nious cladograms supports the monophyly of the entire species swarm. T he closest outgroup appears to be the south-east Asian-Pacific genus L orostema Motschulsky, whose species are distributed from India and Sri Lanka to Tahiti, supporting derivation of the Hawaiian platynines fro m a source in the western or south-western Pacific. The biogeographic relationships of the Hawaiian taxa are analysed using tree mapping, wh erein items of error are minimized. The area cladogram found to be mos t congruent with the phylogenetic relationships, and most defensible b ased on underlying character data is {Kauai[Oahu(Hawaii{Lanai[East Mau i(West Maul + Molokai)]})]}. This progressive vicariant pattern incorp orates progressive colonization from Kauai, and vicariance of the form er Maul Nui into the present islands of Molokai, Lanai, West Maul and East Maul. The evolution of flightlessness, tarsal structure, pronotal setation and bursal asymmetry are evaluated in the context of the cla dogram. Brachyptery is a derived condition for which reversal is not m andated by the cladogram, although repeated evolution of reduced fligh t wings is required. Tarsal structure supports Sharp's (1903) recognit ion of Division 1 as a monophyletic assemblage, but exposes his Divisi on 2 as a paraphyletic group requiring removal of the genus Colpocaccu s Sharp. Pronotal setation is exceedingly homoplastic, and is not usef ul for delimiting natural groups. Left-right asymmetry of the bursa co pulatrix reversed twice independently, resulting in mirror-image bursa l configurations in B. rupicola and Prodisenochus terebratus of East M aui. The amount of character divergence is greater among species compr ising Division I than among species of its sister group, the redefined Division 2. Based on superior fit of Division 1 relationships to the general biogeographic pattern, a greater speciation rate coupled with more extensive extinction is rejected as the cause for this greater di vergence. Intrinsic differentiation in the processes underlying cuticu lar evolution appears to be more consistent with the observed biogeogr aphic and morphological patterns.