Strumigenys perplexa

Strumigenys perplexa
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Attini
Genus:	Strumigenys
Species:	S. perplexa
Binomial name
Strumigenys perplexa (Smith, F., 1876) Specimen labels
Synonyms
Strumigenys antarctica Forel, 1892 Strumigenys leae Forel, 1913

Bolton (2000) - By far the most common and widely distributed dacetine in Australia, S. perplexa also occurs in New Zealand and on Lord Howe Island, Norfolk Island and Philip Island. It is known to be the host species of the socially parasitic Strumigenys xenos in the first two of these localities (Brown, 1955; Taylor, 1968a).

At a Glance

• Limited invasive

Identification

Bolton (2000) - A member of the signeae complex in the Strumigenys godeffroyi-group. Among the Austral members of the signeae-complex perplexa, together with Strumigenys geryon, Strumigenys gryphon, Strumigenys cingatrix and Strumigenys deuteras, are characterised, and easily recognised, by the 3 or 4 distinct pairs of stiffly erect stout hairs on the mesonotum. Of these, geryon and gryphon have numerous long slender hairs on the first gastral tergite that are finely filiform to flagellate, whereas gastral hairs in the remainder are short, stiffly erect and tend to be blunt apically. S. perplexa is distinguished from its closest congeners, cingatrix and deuteras by the characters given in the key, but see also the notes under cingatrix.

Of all the large amount of perplexa material examined the vast majority has MI 40-48. However, a few samples, mostly from Queensland and northern New South Wales, have shorter mandibles, MI 34-38. These samples also tend to be dark in colour, have a head that on average is somewhat narrower (CI 69-75, as opposed to CI 73-79), have a lateral alitrunk that is mostly unsculptured, and have fewer rows of hairs on the first gastral tergite; in extreme cases the hairs are reduced to merely an apical and a basal row. I had initially separated these few series as a sibling species, but the acquisition of more material produced individuals that were intermediate in one or more of these characters. In effect there may be two or even more close sibling species here. I can not resolve the problem at this time so all are retained here as a single species. A more detailed analysis in the future, when more of the supposed intermediates are available, may produce different results.

Keys including this Species

• Key to Australian Strumigenys Species
• Myrmicinae of the southwestern Australian Botanical Province

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -25.91666667° to -41.35°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Australasian Region: Australia (type locality), Lord Howe Island, New Zealand (type locality), Norfolk Island.
Indo-Australian Region: Philippines.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Brown (1954) - Strumigenys perplexa shows surprisingly wide tolerance with respect to nesting sites, and has been found in dry, open woodland in South Australia and western Victoria, as well as in the dark, moist fern gullies in the hills east of Melbourne.

Castes

Worker

.	Owned by Museum of Comparative Zoology.

Images from AntWeb

Worker. Specimen code casent0172367. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by ANIC, Canberra, Australia.

Queen

Images from AntWeb

Queen (alate/dealate). Specimen code casent0172368. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by ANIC, Canberra, Australia.

Queen (alate/dealate). Specimen code casent0178475. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by CAS, San Francisco, CA, USA.

Queen (alate/dealate). Specimen code casent0178872. Photographer Erin Prado, uploaded by California Academy of Sciences.	Owned by CAS, San Francisco, CA, USA.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• perplexa. Orectognathus perplexus Smith, F. 1876c: 491 (w.q.) NEW ZEALAND. Wheeler, G.C. & Wheeler, J. 1955a: 140 (l.); Wheeler, G.C. & Wheeler, J. 1973c: 214 (l.). Combination in Strumigenys: Emery, 1897c: 575. Senior synonym of antarctica: Emery, 1924d: 321; of leae: Brown, 1958h: 38. See also: Bolton, 2000: 967.
• antarctica. Strumigenys antarctica Forel, 1892c: 338 (w.) NEW ZEALAND. Junior synonym of perplexa: Emery, 1924d: 321.
• leae. Strumigenys leae Forel, 1913g: 182 (w.q.) AUSTRALIA (Tasmania). Junior synonym of perplexa: Brown, 1958h: 38.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

Worker

Bolton (2000) - TL 2.0-2.6, HL 0.53-0.65, HW 0.42-0.49, CI 69-79, ML 0.21-0.30, MI 34-48, SL 0.29-0.36, SI 68-78, PW 0.25-0.30, AL 0.53-0.68 (35 measured).

With characters of signeae-complex. Apical fork of right mandible with a single small intercalary tooth. Apicoscrobal hair short, stiff and simple, straight or very shallowly curved. Cephalic dorsum sharply reticulate-punctate; 4-6 short standing hairs present along occipital margin, sometimes also with a short erect pair near highest point of vertex. Main row of projecting hairs on leading edge of scape spatulate and curved; secondary hairs on the edge distinctly shorter and very much more slender, the two sets of hairs easily distinguished. Pronotal humeral hair stiff and simple, straight to shallowly curved; pronotal dorsum with 1-3 pairs of stiffly erect simple hairs and mesonotum with 3 (rarely 4) similar pairs. Entire dorsal alitrunk finely and densely reticulate-punctate. Side of pronotum varying from entirely reticulate-punctate to almost entirely smooth. Katepisternum smooth, at most with weak traces of sculpture around extreme periphery. Metapleuron and side of propodeum varying from almost entirely reticulate-punctate to almost entirely smooth; commonly with a variably sized smooth patch that extends over the upper portion of the metapleuron and lower portion of the side of the propodeum. Postpetiole usually unsculptured and smooth but often with traces of sculpture peripherally; never entirely sculptured over whole disc. Hairs on first gastral tergite short and straight, simple and stiffly erect, apically blunt; hairs usually evenly distributed over sclerite but in some populations reduced medially and sometimes with only a basal and an apical transverse row. Basigastral costulae usually shorter than disc of postpetiole, less commonly about as long as disc.

Type Material

Bolton (2000) - Syntype workers and queen, NEW ZEALAND: Tairua, near Mercury Bay (Brown) (The Natural History Museum) [examined].

• Orectognathus perplexus Smith, 1876: Syntype, worker(s), queen(s), Tairua, near Mercury Bay, New Zealand, The Natural History Museum.
• Strumigenys antarctica Forel, 1892: Syntype, worker(s), Drury, Auckland, New Zealand, Musee d'Histoire Naturelle Genève.
• Strumigenys leae Forel, 1913: Syntype, 3 workers, Chudleigh, Tasmania, Australia, Museum of Comparative Zoology.
• Strumigenys leae Forel, 1913: Syntype, worker(s), Tasmania, Australia, Musee d'Histoire Naturelle Genève.

References

• Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028. (page 967, figs. 524, 546 redescription of worker)
• Brown, W. L., Jr. 1954b. A preliminary report on dacetine ant studies in Australia. Ann. Entomol. Soc. Am. 46: 465-471.
• Brown, W. L., Jr. 1958h. A review of the ants of New Zealand. Acta Hymenopterol. 1: 1-50 (page 38, senior synonym of leae)
• Emery, C. 1897c. Formicidarum species novae vel minus cognitae in collectione Musaei Nationalis Hungarici quas in Nova-Guinea, colonia germanica, collegit L. Biró. Természetr. Füz. 20: 571-599 (page 575, Combination in Strumigenys)
• Emery, C. 1924f [1922]. Hymenoptera. Fam. Formicidae. Subfam. Myrmicinae. [concl.]. Genera Insectorum 174C: 207-397 (page 321, senior synonym of antarctica)
• Hamer, M.T., Telfer, M.G., Turner, C.R. 2023. Rediscovered after 102 years: Strumigenys rogeri (Formicidae; Myrmicinae) is rediscoverd in Britain from the Eden Project East Cornwall (VC 22). British Journal of Entomology, Natural History 36, 225-231.
• Hamer, M.T., Turner, C.R. 2024. Strumigenys emmae (Emery, 1890) (Myrmicinae) new to Britain, with an updated key to the known Strumigenys of the West Palaearctic. Zootaxa 5415(4), 570–576 (doi:10.11646/zootaxa.5415.4.6).
• Heterick, B.E. 2021. A guide to the ants of Western Australia. Part I: Systematics. Records of the Western Australian Museum, Supplement 86, 1-245 (doi:10.18195/issn.0313-122x.86.2021.001-245).
• Heterick, B.E. 2022. A guide to the ants of Western Australia. Part II: Distribution and biology. Records of the Western Australian Museum, supplement 86: 247-510 (doi:10.18195/issn.0313-122x.86.2022.247-510).
• Purkaret, A., Repta, F., Selnekovic, D., Jancik, L., Holecova, M. 2021. Notes on Strumigenys argiola (Emery, 1869) (Hymenoptera: Formicidae) with emphasis on its distribution, ecology and behaviour. Entomofauna Carpathica 33(2): 73-88.
• Smith, F. 1876c. Descriptions of three new species of Hymenoptera (Formicidae) from New Zealand. Trans. Entomol. Soc. Lond. 1876: 489-492 (page 491, worker, queen described)
• Wang, C., Lin, C.-C., Keller, R.A., Billen, J. 2021. The ‘hairwheels’ in Strumigenys ants are not glandular. Asian Myrmecology 13: e013004 (doi:10.20362/am.013004).
• Wheeler, G. C.; Wheeler, J. 1955a [1954]. The ant larvae of the myrmicine tribes Basicerotini and Dacetini. Psyche (Camb.) 61: 111-145 (page 140, larva described)
• Wheeler, G. C.; Wheeler, J. 1973c. The ant larvae of the tribes Basicerotini and Dacetini: second supplement (Hymenoptera: Formicidae: Myrmicinae). Pan-Pac. Entomol. 49: 207-214 (page 214, larva described)

References based on Global Ant Biodiversity Informatics

• Andersen A. N. 1983. A brief survey of ants in Glenaladale National Park, with particular reference to seed-harvesting. Victorian Naturalist 100(6): 233-237.
• Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
• Chong C-S., L. J. Thomson, and A. A. Hoffmann. 2011. High diversity of ants in Australian vineyards. Australian Journal of Entomology 50: 7-21.
• Chong C. S., C. F. D'Alberto, L. J. Thomson, and A. A. Hoffmann. 2010. Influence of native ants on arthropods communities in a vineyard. Agricultural and Forest Entomology 12: 223-232.
• Clay R. E., and K. E. Schneider. 2000. The ant (Hymenoptera: Formicidae) fauna of coastal heath in south-west Victoria: effects of dominance by Acacia sophorae and management actions to control it. Pacific Conservation Biology 6: 144-151.
• Cumber, R. A. 1959. Distributional and biological notes on sixteen North Island species of Formicidae (Hymenoptera). New Zealand Entomologist 2(4):10-14.
• Cumber, R.A. 1959. Distributional and biological notes on sixteen North Island species of Formicidae (Hymenoptera)
• Forel A. 1913. Fourmis de Tasmanie et d'Australie récoltées par MM. Lae, Froggatt etc. Bull. Soc. Vaudoise Sci. Nat. 49: 173-195
• Hoffmann, B. D., R. Graham, and D. Smith. 2017. Ant species accumulation on Lord Howe Island highlights the increasing need for effective biosecurity on islands. NeoBiota 34:41-52.
• Lowery B. B., and R. J. Taylor. 1994. Occurrence of ant species in a range of sclerophyll forest communities at Old Chum Dam, north-eastern Tasmania. Australian Entomologist 21: 11-14.
• Schnell M. R., A. J. Pik, and J. M. Dangerfield. 2003. Ant community succession within eucalypt plantations on used pasture and implications for taxonomic sufficiency in biomonitoring. Austral Ecology 28: 553–565.
• Sinclair J. E., and T. R. New. 2004. Pine plantations in south eastern Australia support highly impoverished ant assemblages (Hymenoptera: Formicidae). Journal of Insect Conservation 8: 277-286.
• Taylor R. W. 1968. The Australian workerless inquiline ant, Strumigenys xenos Brown (Hymenoptera - Formicidae) recorded from New Zealand. New Zealand Entomologist 4(1): 47-49
• Taylor R. W. 1987. A checklist of the ants of Australia, New Caledonia and New Zealand (Hymenoptera: Formicidae). CSIRO (Commonwealth Scientific and Industrial Research Organization) Division of Entomology Report 41: 1-92.
• Taylor R. W., and D. R. Brown. 1985. Formicoidea. Zoological Catalogue of Australia 2: 1-149. 
• Wheeler W.M. 1935. Check list of the ants of Oceania. Occasional Papers of the Bernice Pauahi Bishop Museum 11(11):1-56.
• Wheeler WM. 1927. Ants of Lord Howe and Norfolk Islands. Proceedings of the American Academy of Arts and Sciences. 62.4: 120-153.
• Wheeler, W. M. 1927. The ants of Lord Howe Island and Norfolk Island. Proc. Am. Acad. Arts Sci. 62: 121-153
• Wheeler, William Morton. 1927. The Ants of Lord Howe Island and Norfolk Island. Proceedings of the American Academy of Arts and Sciences 62(4): 121-153
• Wheeler, William Morton.1935.Checklist of the Ants of Oceania.Occasional Papers 11(11): 3-56