Myrmecia esuriens

Myrmecia esuriens
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmeciinae
Genus:	Myrmecia
Species:	M. esuriens
Binomial name
Myrmecia esuriens F. Smith, 1858

Myrmecia esuriens, also known as Tasmanian Inchman, is a species of bulldog ant that is native to Tasmania.

Morphology

The largest size of this bull ant species is reached by the queen, approximately 22 to 24 millimetres (0.87 to 0.94 in) long. Males ("drones") grow to 16 mm (0.63 in), and the worker ants average 14 to 18 mm (0.55 to 0.71 in) long.^[1] Within its genus, M. esuriens is a medium-sized species, as sizes for Myrmecia range from 6 mm (0.24 in) to more than 30 mm (1 in).^[2][3]

The main body of the ant is black with a single segment of the abdomen, the postpetiole, coloured an orange-red. The mandibles, antennae, and legs of the ants are also orange-red. The hair on the ant is yellow, and is short on the head, thorax, and legs and longer on the gaster. No hair is present on the scapes.^[1][4]

The mandibles are long and straight, and of the eleven teeth present, the third, fifth, seventh, and ninth are wider and longer than the other seven. The Tasmanian Inchman has good eyesight, useful outside of the nest for defence and foraging.^[1][2]

Unusually for ants, the queens are noted for not having wings, and instead an ergatoid (worker-like) form.^[1][5] This corresponds with the consideration of the Myrmecia genus as primitive, with several features, such as the presence of ocelli and a well-defined mesonotum, suggestive of earlier evolutionary development.^[3]

Habitat

Endemic to Tasmania, the Tasmanian Inchman inhabits forest, rocky land, and undergrowth, and can often be found under fallen trees. They nest in soil, making mounds that are sometimes partially covered by pebbles or vegetation.^[2][6][7]

Behaviour and other characteristics

The worker ants of the species forage for food in low vegetation and on the ground. Although they themselves are not carnivorous and prefer to feed on nectar and other sweet substances, they do scavenge and hunt prey, which they feed to the ant larvae. Bulldog ants are known for being aggressive and defensive of nests, and use their mandibles and sting to fight off attackers.^[2][3][6]

Myrmecia esuriens is closely related to M. pilosula, the venomous jack jumper ant, the sting of which is known to be deadly to humans sensitive or allergic to the venom. Although M. esuriens also inflicts stings, there is no written information on its venom being harmful to humans. This may be due to relative sting strength and composition or possibly due to M. esuriens not being as prevalent or widespread, contributing to a lack of evidence.^[8] The sting is painful, however, though anecdotal evidence suggests that the pain is short-lived.^[2][9]

In January 1777, Captain Cook's ships HMS Resolution and HMS Discovery landed at Adventure Bay, Tasmania. On 30 January, William Anderson, a surgeon and naturalist aboard HMS Resolution, wrote of two "troublesome" insects of Tasmania, one being the mosquitoes and the other "a large black Ant whose bite is almost intolerable for the short time it lasts". The ants stinging Anderson were almost certainly Myrmecia esuriens.^[9]

Notes

1. ^ ^{a b c d} Shattuck, Steve (2009). "Myrmecia esuriens Fabricius, 1804". Ants Down Under. Commonwealth Scientific and Industrial Research Organisation (CSIRO). http://anic.ento.csiro.au/ants/biota_details.aspx?biotaid=37416. Retrieved 2009-08-18. 
2. ^ ^{a b c d e} Shattuck, Steve (2000). Australian Ants: Their Biology and Identification. 3. CSIRO Publishing. pp. 119–120. ISBN 9780643066595. http://books.google.com/?id=lYCh_VOaVm4C&dq=Myrmecia+esuriens. 
3. ^ ^{a b c} Ogata, Kazuo (1991). "Ants of the genus Myrmecia Fabricius: a review of the species group and their phylogenetic relationships". Systematic Entomology (Royal Entomological Society) 16: 353–381. http://www.agr.kyushu-u.ac.jp/tropic/ehome/paper2.pdf. Retrieved 2009-08-18. 
4. ^ "Tasmanian Inchman Facts". Australian Wildlife. www.ozanimals.com. http://www.ozanimals.com/Insect/Tasmanian-Inchman/Myrmecia/esuriens.html. Retrieved 2009-08-18. 
5. ^ Clark, John (September 1934). "Notes on Australian ants, with descriptions of new species and a new genus". Memoirs of the National Museum, Melbourne (Melbourne: National Museum) (8): 5. http://antbase.org/ants/publications/6105/6105.pdf. Retrieved 2009-08-18. 
6. ^ ^{a b} Daley, Elizabeth; Daley, Anthony (2007). Wings: an introduction to Tasmania's winged insects. Riffles Pty. Ltd. p. 7. ISBN 9780980400625. http://books.google.com/?id=PQOaPwAACAAJ&dq=elizabeth+daley. 
7. ^ Grove, Simon; Richards, Karen; Spencer, Chris; Yaxley, Belinda (2006). "What lives under large logs in Tasmanian eucalypt forest?". The Tasmanian Naturalist (Tasmanian Field Naturalists Club) 128: 86–93. http://www.tasfieldnats.org.au/TasNatArticles/TasNat128/TN128-GROVE2.pdf. Retrieved 2009-08-18. 
8. ^ Brown, Simon G. A.; Franks, Rodney W.; Baldo, Brian A.; Heddle, Robert J. (January 2003). "Prevalence, severity, and natural history of jack jumper ant venom allergy in Tasmania". Journal of Allergy and Clinical Immunology (Elsevier, Inc) 111 (1): 187–192. doi:10.1067/mai.2003.48. PMID 12532117. http://download.journals.elsevierhealth.com/pdfs/journals/0091-6749/PIIS0091674902913102.pdf. Retrieved 2009-08-18. 
9. ^ ^{a b} Cook, James; Anderson, William (1967). Beaglehole, John Cawte. ed. The Journals of Captain James Cook on his voyages of discovery. 3. University of California. p. 794. ISBN 0851157440.