Discothyrea

Discothyrea Temporal range: 20.43–0 Ma K Pa Eo Ol Mi Pl Early Miocene – Recent
Discothyrea testacea
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Proceratiinae
Tribe:	Proceratiini
Genus:	Discothyrea Roger, 1863
Type species
Discothyrea testacea
Diversity
49 species 2 fossil species (Species Checklist, Species by Country) Discothyrea testacea Specimen Label
Synonyms
Prodiscothyrea Wheeler, W.M., 1916 Pseudosysphincta Arnold, 1916

Discothyrea are all small, relatively cryptic ants with small colonies (10-20 workers) which are generally found in rotten wood, leaf litter, or under stones (Brown, 1958a; Bolton, 1973a). Brown (1958a) first mentioned the possibility that they could be specialised predators of arthropod eggs since the closely related genus Proceratium shows such a trophic specialisation, and was able to find evidence for his theory on the basis of observations of an Australian Discothyrea species (Brown, 1958b). Most studied species prefer spider eggs, although one species was found in the nests of other ants (Brown, 1980). Queens of one African species found their nests within spider egg sacs, which provide both food and lodging for the first generation of workers (Dejean and Dejean 1998).

At a Glance

• Ergatoid queen

Photo Gallery

• 

  Single worker of Discothyrea sauteri collected from Yeosu, Korea. Photo by Minsoo Dong.
• 

  A Discothyrea queen from Ecuador. Photo by Phil Hoenle.

Identification

Bharti et al. (2015) - This distinctive genus can be easily recognized with large terminal antennal segment, reduced frontal lobes, short antennal scapes, and strongly arched 2nd gastral segment. However, the genus may be confused with the closely related Proceratium from which it is differentiated by the single tooth at the tip of the mandibles, the overhanging anterior margin of the clypeus, and the configuration of the antennae [Sarnat, Economo, 2012].

See images of species within this genus

Keys including this Genus

• Key to Australian Genera of Proceratiinae
• Key to Neotropical Proceratiinae genera
• Key to North American Genera of Proceratiinae
• Key to Vietnamese Proceratiinae Genera

 

Keys to Species in this Genus

• Key to Oriental Discothyrea
• Key to Discothyrea of the southwestern Australian Botanical Province
• Key to Afrotropical Discothyrea
• Key to the Discothyrea of the Neotropical Atlantic Rainforest

Distribution

Species by Region

Number of species within biogeographic regions, along with the total number of species for each region.

	Afrotropical Region	Australasian Region	Indo-Australian Region	Malagasy Region	Nearctic Region	Neotropical Region	Oriental Region	Palaearctic Region
Species	20	7	5	1	1	11	6	5
Total Species	2841	1736	3045	932	835	4379	1741	2862

Fossils

Fossils are known from: Dominican amber, Dominican Republic (Burdigalian, Early Miocene), Mexican amber, Chiapas, Mexico (Middle Miocene), Zhangpu amber, Zhangpu County, Fujian Province, China (Miocene) (an unidentified species, Wang et al., 2021).

Biology

Life History Traits

• Queen type: winged or dealate; ergatoid (Peeters, 1997)
• Mean colony size: 73 (Greer et al., 2021)
• Compound colony type: not parasitic (Greer et al., 2021)
• Nest site: hypogaeic (Greer et al., 2021)
• Diet class: predator (Greer et al., 2021)
• Foraging stratum: subterranean/leaf litter (Greer et al., 2021)

Castes

Brown (1958: p.251) described ergatoid queens in some species.

Morphology

Worker Morphology

 Explore: Show all Worker Morphology data or Search these data. See also a list of all data tables or learn how data is managed.

 • Eyes: 11-100 ommatidia • Pronotal Spines: absent • Mesonotal Spines: absent • Propodeal Spines: absent • Petiolar Spines: absent • Caste: none or weak • Sting: present • Metaplural Gland: present • Cocoon: present

Figure 6. Labiomaxillary complexes of some Discothyrea: A-B) SEM images of Discothyrea oculata labiomaxillary complex (ANTWEB1008518, available at Antweb, images by Roberto Keller); C) Discothyrea clavicornis (UFV-LABECOL-011021), also showing a 6,4 palpal formula; D) D. neotropica (UFV-LABECOL-000067) with a 3,2 palpal formula; E) Discothyrea horni (UFVLABECOL-009622), 2,2 palpal formula; F) Discothyrea sexarticulata (UFV-LABECOL-010770), 2,2 palpal formula. Circles and squares represent the maxillary and labial palpomeres, respectively. Dark blue is the first palpomere; light blue is the second; red is the third; black is the fourth; white is the fifth; and green is the sixth. Arrowheads in C and F indicate basal bent of first palpomere (not a division between two palpomeres).

Figure 7. Antennal pits revealed in 3D models of some Afrotropical Discothyrea: A and B) Discothyrea michelae, dorsal view of the antenna and zoom in first flagellomere; C and D) D. michelae, ventral view of the antenna and zoom in penultimate flagellomere; E and F) Discothyrea gaia, lateral view of the antenna and zoom in penultimate and antepenultimate flagellomeres. Zoomed areas of B, D and F highlighted in A, C and E by red squares. The 3D models of the species are available at the Dryad Digital Repository (Hita-Garcia et al., 2019a, 2019b), and are also available at the Sketchfab page of the the Economo Lab, from the Okinawa Institute of Science and Technology (OIST-Economolab, s. d.a).

Karyotype

Species Uncertain

• n = 15, 2n = 30 (Indonesia) (Imai et al., 1985; Mariano et al., 2015) (near D. bryanti).

All Karyotype Records for Genus

• See additional details at the Ant Chromosome Database.

 Explore: Show all Karyotype data or Search these data. See also a list of all data tables or learn how data is managed.

Click here to show/hide karyotype data.

Taxon	Haploid	Diploid	Karyotype	Locality	Source	Notes
Discothyrea	15	30		Indonesia	Imai et al., 1985; Mariano et al., 2015	near ''D. bryanti''

Nomenclature

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

• DISCOTHYREA [Proceratiinae: Proceratiini]
  • Discothyrea Roger, 1863a: 176. Type-species: Discothyrea testacea, by monotypy.
  • Discothyrea senior synonym of Prodiscothyrea, Pseudosysphincta: Brown, 1958g: 248.
• PRODISCOTHYREA [junior synonym of Discothyrea]
  • Prodiscothyrea Wheeler, W.M. 1916i: 33. Type-species: Prodiscothyrea velutina, by monotypy.
  • Prodiscothyrea junior synonym of Discothyrea: Brown, 1958g: 248.
• PSEUDOSYSPHINCTA [junior synonym of Discothyrea]
  • Pseudosysphincta Arnold, 1916: 161. Type-species: Pseudosysphincta poweri, by original designation.
  • Pseudosysphincta junior synonym of Discothyrea: Brown, 1958g: 248.
• [Pseudosphincta Wheeler, W.M. 1922a: 645, incorrect subsequent spelling.]

References

• Ashmead, W. H. 1905c. A skeleton of a new arrangement of the families, subfamilies, tribes and genera of the ants, or the superfamily Formicoidea. Can. Entomol. 37: 381-384 (page 382, Discothyrea in Ponerinae, Proceratiini)
• Barden, P. 2017. Fossil ants (Hymenoptera: Formicidae): ancient diversity and the rise of modern lineages. Myrmecological News 24: 1-30.
• Billen, J., Khalife, A., Ito, F., Anh, N.D., Esteves, F.A. 2021. The basitarsal sulcus gland, a novel exocrine structure in ants. Arthropod Structure, Development 61, 101041 (doi:10.1016/j.asd.2021.101041).
• Bolton, B. 1994. Identification guide to the ant genera of the world. Cambridge, Mass.: Harvard University Press, 222 pp. (page 164, Discothyrea in Ponerinae, Ectatommini)
• Bolton, B. 2003. Synopsis and Classification of Formicidae. Mem. Am. Entomol. Inst. 71: 370pp (page 179, Discothyrea in Ponerinae, Ectatommini)
• Boudinot, B.E., Richter, A.K., Hammel, J.U., Szwedo, J., Bojarski, B., Perrichot, V. 2022. Genomic-phenomic reciprocal illumination: Desyopone hereon gen. et sp. nov., an exceptional Aneuretine-like fossil ant from Ethiopian amber (Hymenoptera: Formicidae: Ponerinae). Insects 13(9), 796 (doi:10.3390/insects13090796).
• Brassard, F., Leong, C.-M., Chan, H.-H., Guénard, B. 2021. High diversity in urban areas: How comprehensive sampling reveals high ant species richness within one of the most urbanized regions of the world. Diversity 13, 358 (doi:10.3390/d13080358).
• Brown, W. L., Jr. 1958g. Contributions toward a reclassification of the Formicidae. II. Tribe Ectatommini (Hymenoptera). Bulletin of the Museum of Comparative Zoology 118: 173-362 (page 248, Discothyrea senior synonym of Prodiscothyrea and Pseudosyphincta; and revision of genus; Discothyrea in Ponerinae, Ectatommini)
• Brown, W. L., Jr. 1958j ("1957"). Predation of arthropod eggs by the ant genera Proceratium and Discothyrea. Psyche (Cambridge) 64:115. [1958-08-14]
• Burchill, A.T., Moreau, C.S. 2016. Colony size evolution in ants: macroevolutionary trends. Insectes Sociaux 63, 291–298 (doi:10.1007/s00040-016-0465-3).
• Cantone S. 2018. Winged Ants, The queen. Dichotomous key to genera of winged female ants in the World. The Wings of Ants: morphological and systematic relationships (self-published).
• Chapman, J. W.; Capco, S. R. 1951. Check list of the ants (Hymenoptera: Formicidae) of Asia. Monogr. Inst. Sci. Technol. Manila 1: 1-327 (page 76, Discothyrea in Ponerinae, Proceratiini)
• Dalla Torre, K. W. von. 1893. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus. Vol. 7. Formicidae (Heterogyna). Leipzig: W. Engelmann, 289 pp. (page 18, Discothyrea in Ponerinae)
• Dlussky, G. M.; Fedoseeva, E. B. 1988. Origin and early stages of evolution in ants. Pp. 70-144 in: Ponomarenko, A. G. (ed.) Cretaceous biocenotic crisis and insect evolution. Moskva: Nauka, 232 pp. (page 78, Discothyrea in Ponerinae, Ectatommini)
• Donisthorpe, H. 1943g. A list of the type-species of the genera and subgenera of the Formicidae. [part]. Ann. Mag. Nat. Hist. 11(10): 617-688 (page 640, Discothyrea in Ponerinae, Proceratiini)
• Emery, C. 1895l. Die Gattung Dorylus Fab. und die systematische Eintheilung der Formiciden. Zool. Jahrb. Abt. Syst. Geogr. Biol. Tiere 8: 685-778 (page 765, Discothyrea in Dorylinae, Proceratiini)
• Fernandez, F., Guerrero, R.J., Sánchez-Restrepo, A.F. 2021. Sistemática y diversidad de las hormigas neotropicales. Revista Colombiana de Entomología 47, 1–20 (doi:10.25100/socolen.v47i1.11082).
• Forel, A. 1917. Cadre synoptique actuel de la faune universelle des fourmis. Bull. Soc. Vaudoise Sci. Nat. 51: 229-253 (page 236, Discothyrea in Ponerinae, Proceratiini)
• Hita-Garcia, F., Lieberman, Z., Audisio, T.L., Liu, C., Economo, E.P. 2019. Revision of the highly specialized ant genus Discothyrea (Hymenoptera: Formicidae) in the Afrotropics with x-ray microtomography and 3D cybertaxonomy. Insect Systematics and Diversity 3(6): 5; 1–84 (doi:10.1093/isd/ixz015).
• Hölldobler, B.; Wilson, E. O. 1990. The ants. Cambridge, Mass.: Harvard University Press, xii + 732 pp. (page 10, Discothyrea in Ponerinae, Ectatommini)
• Jaffe, K. 1993. El mundo de las hormigas. Baruta, Venezuela: Equinoccio (Ediciones de la Universidad Simón Bolívar), 188 pp. (page 8, Discothyrea in Ponerinae, Proceratiini)
• Kaspari, M., Pickering, J., Longino, J., Windsor, D. 2001. The phenology of a Neotropical ant assemblage: evidence for continuous and overlapping reproduction. Behavioral Ecology and Sociobiology 50, 382–390 (doi:10.1007/s002650100378).
• Kempf, W. W. 1972b. Catálogo abreviado das formigas da regia~o Neotropical. Stud. Entomol. 15: 3-344 (page 97, Discothyrea in Ponerinae, Ectatommini)
• Kreider, J.J., Chen, T.W., Hartke, T.R., Buchori, D., Hidayat, P., Nazarreta, R., Scheu, S., Drescher, J. 2021. Rainforest conversion to monocultures favors generalist ants with large colonies. Ecosphere 12 (doi:10.1002/ecs2.3717).
• Kusnezov, N. 1964 [1963]. Zoogeografía de las hormigas en Sudamérica. Acta Zool. Lilloana 19: 25-186 (page 51, Discothyrea in Ponerinae, Proceratiini)
• Lattke, J. E. 1994. Phylogenetic relationships and classification of ectatommine ants (Hymenoptera: Formicidae). Entomol. Scand. 25: 105-119 (page 112, Discothyrea in Ponerinae, Proceratiini)
• Mariano, C.S.F., Santos, I.S., Silva, J.G., Costa, M.A., Pompolo, S.G. 2015. Citogenética e evolução do cariótipo em formigas poneromorfas. In: Delabie, J.H.C., Feitosa, R.M., Serrao, J.E., Mariano, C.S.F., Majer, J.D. (eds) As formigas poneromorfas do Brasil, 1st edn. Ilhéus, Brasil, pp 102–125 (doi:10.7476/9788574554419.0010).
• Mayr, G. 1865. Formicidae. In: Reise der Österreichischen Fregatte "Novara" um die Erde in den Jahren 1857, 1858, 1859. Zoologischer Theil. Bd. II. Abt. 1. Wien: K. Gerold's Sohn, 119 pp. (page 13, Discothyrea in Ponerinae [Poneridae])
• Peeters, C. 1997. Morphologically “primitive” ants: comparative review of social characters, and the importance of queen-worker dimorphism. Pages 372-391 In: Choe, J. & B. Crespi (eds) The Evolution of Social Behavior in Insects and Arachnids. Cambridge University Press. (doi:10.1017/CBO9780511721953.019).
• Roger, J. 1863a. Die neu aufgeführten Gattungen und Arten meines Formiciden-Verzeichnisses nebst Ergänzung einiger früher gegebenen Beschreibungen. Berl. Entomol. Z. 7: 131-214 (page 176, Discothyrea as genus)
• Smith, D. R. 1979. Superfamily Formicoidea. Pp. 1323-1467 in: Krombein, K. V., Hurd, P. D., Smith, D. R., Burks, B. D. (eds.) Catalog of Hymenoptera in America north of Mexico. Volume 2. Apocrita (Aculeata). Washington, D.C.: Smithsonian Institution Pr (page 1339, Discothyrea in Ponerinae, Ectatommini)
• Wang, B., Shi, G., Xu, C., Spicer, R. A., Perrichot, V., Schmidt, A. R., Feldberg, K., Heinrichs, J., Chény, C., Pang, H., Liu, X., Gao, T., Wang, Z., Ślipiński, A., Solórzano-Kraemer, M. M., Heads, S. W., Thomas, M. J., Sadowski, E. M., Szwedo, J., Azar, D., Nel, A., Liu, Y., Chen, J., Zhang, Q., Zhang, Q., Luo, C., Yu, T., Zheng, D., Zhang, H., Engel, M. S. 2021. The mid-Miocene Zhangpu biota reveals an outstandingly rich rainforest biome in East Asia. Science advances, 7(18), eabg0625 (doi:10.1126/sciadv.abg0625).
• Weber, N. A. 1939a. New ants of rare genera and a new genus of ponerine ants. Ann. Entomol. Soc. Am. 32: 91-104 (page 99, Key to Neotropical species)
• Wheeler, G. C.; Wheeler, J. 1985b. A simplified conspectus of the Formicidae. Trans. Am. Entomol. Soc. 111: 255-264 (page 256, Discothyrea in Ponerinae, Proceratiini)
• Wheeler, W. M. 1910b. Ants: their structure, development and behavior. New York: Columbia University Press, xxv + 663 pp. (page 136, Discothyrea in Ponerinae, Proceratiini)
• Wheeler, W. M. 1922i. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. VII. Keys to the genera and subgenera of ants. Bull. Am. Mus. Nat. Hist. 45: 631-710 (page 645, Discothyrea in Ponerinae, Proceratiini)