Professor Emeritus Cornell University Ithaca, New York
Paratachys terryli Liebherr is Kauai’s representative to a Hawaiian radiation also including species endemic to O‵ahu, Moloka‵i, Maui, and Hawai‵i Island. Paratachys terryli inhabits high-elevation summit bog forest and streamside habitats where the beetles occupy voids under rocks or within moss. The species exhibits both ocular and flight-wing polymorphisms. Individuals vary in eye development from macrophthalmic, with large convex compound eyes comprising over 100 ommatidia, to microphthalmic, with small flat eyes composed of only 20 ommatidia. Intermediate numbers of ommatidia are also observed suggesting that eye development is polygenically determined. Paratachys terryli also exhibits flight-wing dimorphism, with nearly all individuals possessing vestigial flight wings, though a single, macrophthalmic female was found to have fully developed wings with venation and dimensions as in the flight-capable Tachys oahuensis Blackburn. Carabid flight-wing dimorphism has been demonstrated to be Mendelian and di-allelic within species of several genera; the derived brachypterous allele being dominant to the wild-type “winged” allele. But in some species factors such as temperature, nutrition, or gender influence wing development. So, there are several obvious questions to ask concerning P. terryli. Is wing development under strict Mendelian control or can nutrition, temperature, or gender influence wing development? Secondly, are ocular and flight-wing polymorphisms under independent genetic control or linked? If independent, microphthalmic, flight-capable beetles are predicted. How would such beetles fare in flight? If the genetic programs are linked, how so? It is fitting that Terry Lee Erwin’s Paratachys leads us to ask deeper questions about carabid evolution.
