Data from: Convergent evolution in the explosive Hawaiian Fancy Cased caterpillar radiation

Species occurring in unconnected, but similar habitats and under similar
selection pressures often display strikingly comparable morphology,
behaviour and life history. On island archipelagos where colonizations and
extinctions are common, it is often difficult to separate whether similar
traits are a result of in situ diversification or independent colonization
without a phylogeny. Here, we use one of Hawaii’s most ecologically
diverse and explosive endemic species radiations, the Hawaiian fancy case
caterpillar genus Hyposmocoma, to test whether in situ diversification has
resulted in convergence. Specifically, we examine whether similar species
utilizing similar microhabitats independently developed largely congruent
larval case phenotypes in lineages that are in comparable, but isolated
environments. Larvae of these moths are found on all Hawaiian Islands and
are characterized by an extraordinary array of ecomorphs and larval case
morphology. We focus on the ‘purse cases’, a group that is largely
specialized for living within rotting wood. Purse cases were considered a
monophyletic group, because morphological, behavioural and ecological
traits appeared to be shared among all members. We constructed a phylogeny
based on nuclear and mitochondrial DNA sequences from 38 Hyposmocoma
species, including all 14 purse-cased species and 24 of non-purse-cased
congeners. Divergence time estimation suggests that purse-cased lineages
evolved independently within dead wood and developed nearly identical case
morphology twice: once on the distant Northwest Hawaiian Islands between
15.5 and 9 Ma and once on the younger main Hawaiian Islands around 3.0 Ma.
Multiple ecomorphs are usually found on each island, and the ancestral
ecomorph of Hyposmocoma appears to have lived on tree bark. Unlike most
endemic Hawaiian radiations that follow a clear stepwise progression of
colonization, purse-cased Hyposmocoma do not follow a pattern of
colonization from older to younger island. We postulate that the diversity
of microhabitats and selection from parasitism/predation from endemic
predators may have shaped case architecture in this extraordinary endemic
radiation of Hawaiian insects.