Long-stemmed Pennant Ant
Tetramorium tonganum
Species Info General
Other common names include: n/a
This interesting ant is a rare denizen of wet forests. In two decades’ worth of surveys conducted by Maui Invasive Species Committee, it has only ever been found in woodland areas from Nāhiku to Kaʻelekū, on the north shore west of Hāna – and usually in low numbers. It was first collected on the island of Tongatapu, the main island in Tonga (hence the species epithet tonganum). However we now know that it is not native to that archipelago.
Huddleston & Fluker (1968) reported that this species “[s]eems to be scarce in its habitats, usually found in higher (over 80 inches) rainfall areas” while Mann (1921) reported that it “[n]ests in small colonies in rotten wood”. Sarnat & Economo (2012) wrote that Tetramorium tonganum “is most often encountered on vegetation in disturbed or edge forest habitat.” On Oʻahu it was found nesting within the stalk of a sugar cane at the Mānoa Substation of the now-defunct Hawaiian Sugar Planters’ Association (Swezey 1927).
Identification/Description
This is an orangish-yellow ant midway in size between our four common Pennant Ants: Tetramorium caldarium and Tetramorium simillimum (aka Confusing Yellow Pennant Ant and Similar Yellow Pennant Ant) are both a bit smaller than the Long-stemmed Pennant Ant, while Tetramorium bicarinatum and Tetramorium insolens (Bicolored Pennant Ant and Insolent Pennant Ant) are both a bit larger.
Impacts
- Not a lot is known about this ant’s habits and potential impacts. Sarnat & Economo (2012) suggested that “it is not believed to cause significant damage to ecological or agricultural systems.”
History
- This species was first noted in the Islands in March of 1926 (Swezey 1927). It is unclear when it was first detected on Maui other than that it was known to be here prior to 1994 (Nishida 1994). It has not yet been recorded on Molokaʻi, Lānaʻi or Kahoʻolawe.
Resources/References
- Tetramorium tonganum – AntWiki
- Huddleston, E. W. & Fluker, S. S. 1968. Distribution of Ant Species of Hawaii. Proceedings of the Hawaiian Entomological Society 20(1): 45–69.
- Mann, W. M. 1921. The Ants of the Fiji Islands. Bulletin of the Museum of Comparative Zoölogy at Harvard College 64: 40–499.
- Nishida, G. M. 1994. Hawaiian Terrestrial Arthropod Checklist (Second Edition). Hawaii Biological Survey Contribution No. 94-04, Bishop Museum Technical Report No. 4.
- Sarnat, E. & Economo, E. P. 2012. The Ants of Fiji. University of California Press, Berkeley & Los Angeles, California. 384 pp.
- Swezey, O. H. 1927. [Notes & Exhibitions]. Tetramorium tonganum Mayr. Proceedings of the Hawaiian Entomological Society 6(3): 367–368.
