Pheidole navigans, Forel, 1901

Matsunaga, Janis N., Howarth, Francis G. & Kumashiro, Bernarr R., 2019, New State Records and Additions to the Alien Terrestrial Arthropod Fauna in the Hawaiian Islands, Proceedings of the Hawaiian Entomological Society 51 (1), pp. 1-71 : 13

Pheidole navigans (= moerens ) Forel

New island record

This species was previously reported as Pheidole moerens Wheeler in Gruner et al. (2003) from Hawaii and by Starr and Starr (2013) from Maui. Sarnat et al. 2015 removed Pheidole navigans Forel, 1901 from synonymy with P. moerens after examining type specimens, as well as representatives from Hawaii. A single minor worker was collected from Lihue, Kauai at a rental car parking lot near the Lihue Airport (13.X.2015, ex. peanut butter baited vial, coll. B. Dietrich, voucher at HDOA), however, we cannot confirm P. navigans without additional specimens including major workers. We report the following Oahu collections as a new island record.

Collection records: OAHU, Mililani, 3.X.2008, at large at a nursery with plants from Hawaii island, coll. R. Change, det. C. Young, 6.X.2008; Waimanalo, 21.VIII.2013, peanut butter baited vial at nursery, coll. D. Arakaki, det. C. Young, 22.VIII.2013. Vouchers at HDOA .

Trichomyrmex destructor (Jerdon) “dark form”

Record of note/Establishment uncertain

Ants collected from Ford Island by a private pest control company were somewhat morphologically similar to local Trichomyrmex (= Monomorium ) destructor populations, however, with minor differences and darker coloration. Individuals from this collection site were also similar to M. mayri (not established in Hawaii), however, DNA analysis (using COI) by R. Clouse and M. Janda placed this population within a T. destructor clade which falls between a T. destructor clade from Madagascar and a T. destructor clade from Melanesia, India, and Palau.

While this population falls within T. destructor , it is important to note that this potentially represents a recent and separate invasion of T. destructor to Hawaii. Further DNA analysis of local T. destructor populations should be done to verify this conclusion, however, the location and cicumstances of the infestation in addition to morphological differences point to a new introduction of a very invasive pest ant species in Hawaii. Vouchers at HDOA.

Collection records: OAHU, Ford Island , 12.X.2012, vienna sausage baited vial, coll. C. Agena, det. R. Clouse and M. Janda, 22.II.2013. Vouchers at HDOA .