Studies in Hawaiian Diptera III: New Distributional Records for Canacidae and a New Endemic Species of Procanace

Abstract

The distributions of Hawaiian Canacidae, comprising nearly 800 individual collection events, are reviewed and a total of four new island records are reported. These include Canaceoides angulatus from Kahoolawae and Procanace bifurcata from Molokai and Maui, and Procanace constricta from Oahu. A new species from Kauai, Procanace hardyi O'Grady and Pak, is described. This species is closely related to P. constricta from Oahu, Maui, Molokai and Hawaii and shares a similar constriction of the abdomen between tergites four and five but differs in the configuration of the seventh abdominal tergite. Detailed distribution maps for all species are included.

The evolution of marine dwelling in Diptera

“…This scenario is likely given that marine dwelling may be a result of a combination of several ecophysiological traits and no one particular trait confers salt tolerance or stress tolerance within the marine environment. Within some families, particularly Canacidae and Coelopidae, adapting to the marine environment may have been gained early on in the evolutionary history and then occasionally lost as some of these lineages transitioned to freshwater environments (O’Grady & Pak, 2016 ). The absence of evidence of reversions to the terrestrial environment within these families suggests that their most recent common ancestor specialized in marine environments.…”