Tapinoma magnum

Tapinoma magnum
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Dolichoderinae
Genus:	Tapinoma
Species group:	nigerrimum
Species:	T. magnum
Binomial name
	Tapinoma magnum; Mayr, 1861

At a Glance

• Supercolonies • Invasive

Tapinoma magnum, probably native to the western part of the Mediterranean basin, is an invasive species in Greece (Borowiec et al., 2022). Known from North Africa from Morocco east to Tunisia, over entire Italy, in Corsica, Sardinia, and southeast and many infested cities in the west of France.

Identification

A member of the Tapinoma nigerrimum complex.

Borowiec and Salata (2022) - Within Greece: Tapinoma magnum and Tapinoma simrothi form a complex of species with deep, parallel sided median emargination of clypeus. They are difficult to determination using only external characters and the best distinguishing character is structure of male genitalia (see Figs 23.4, 5 and 24.7, 8). Tapinoma magnum has more setose anterior part of clypeus with longer marginal setae, some small setae reaching behind lateral and posterior margin of median emargination while in T. simrothi none or at most 2 of short setae reach behind the margin of median emargination. Tapinoma magnum is an invasive species in Greece, it was recorded only from tourist area in one island of the Dodecanese Archipelago. While T. simrothi is widespread in continental and insular Greece, most likely sympatric with T. magnum on Dodecanese.

Keys including this Species

Distribution

Seifert et al. (2017) - North Africa from Morocco east to Tunisia, over entire Italy, in Corsica, Sardinia, and southern France.

Latitudinal Distribution Pattern

Latitudinal Range: 52.3° to 30.7°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps, Seifert et al. (2024)

Distribution based on Regional Taxon Lists

Palaearctic Region: Algeria, Azerbaijan, Belgium, France, Germany, Greece, Italy (type locality), Morocco, Netherlands, Spain, Tunisia.

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

Seifert et al. (2017) - The supercolonial Tapinoma magnum has by far the widest distribution among the four species in its group (Tapinoma darioi, Tapinoma ibericum, Tapinoma nigerrimum). It showed the strongest invasive potential of the three supercolonial species and was anthropogenically introduced to nine sites in Germany, Belgium, and the Netherlands (Heller 2011, Dekoninck & al. 2015) which are all situated north of 48° N. Tapinoma magnum became here a pest species with strong local impacts. The beachheads for the German introductions were garden centers and tree nurseries and for the Belgian introduction probably the harbor of Oostende. The frost resistance and low foraging temperatures are remarkable for a Mediterranean ant. Colonies survived in Germany a 14-days frost period with mean air temperatures of -6.6 °C and an absolute minimum of -15 °C without any visible damage (Dekoninck & al. 2015). The German populations of T. magnum showed the last activity in late December at air temperatures of 8 °C and resumed activity after snowmelt in January during a cloudy day and mean and maximum air temperatures of 10.6 and 12.2 °C (Dekoninck & al. 2015; G. Heller, pers. comm.).

In the Mediterranean area, Tapinoma magnum is particularly abundant in open unstable or degraded areas with significant to very strong anthropogenic influence and a weakly developed tree layer. It is more abundant on sandy soils and significantly rarer on rock. If reports from South France (Bernard 1968, 1983) should largely refer to T. magnum, it shows a quite developed tolerance against flooding, occurs in high numbers on irrigated clay soils in areas of market gardening and is found even in swampy habitats. Tapinoma magnum seems to be absent from Iberia except for a beachhead in southernmost Spain. The rarity in Spain is somewhat surprising considering the strong invasive potential of T. magnum. The dominance of the supercolonial Tapinoma ibericum in southern Iberia and of the supercolonial T. darioi in northern Spain probably will have hampered a colonization of these areas by T. magnum. We got the general impression that syntopic occurrence of the three supercolonial species is exceptional.

According to geography of collecting sites (we did not get samples from the authors), the investigations of Blight & al. (2010) can be referred with a fair probability to Tapinoma magnum, but T. darioi cannot be excluded. Blight & al. (2010) showed that their Tapinoma ants limited the spread of the invasive Argentine Ant, Linepithema humile in Corsica and southern France. In space and food competition assays the Tapinoma species of Blight & al. (2010) was more efficient than Linepithema in both interference and exploitative competition, clearly superior in direct fighting, dominated food in 100% of the replicates after one hour, and invaded Linepithema nests while the reverse was never observed. Such isolated laboratory investigations do not necessarily tell us who is the final winner in a particular outdoor confrontation because this is determined not only by basic fighting and recruiting properties but also by ecological adaptation and demographic factors. Strong intraspecific aggressivity between polydomous colonies of T. magnum in gardener's centres of Germany suggests either repeated introductions to the same site or secondary colony splitting – artificially isolated colony fragments developed a significant aggressivity between former nest mates already six months after separation (G. Heller, pers. comm.). Protection of vine and citrus mealybug colonies by T. magnum (a posteriori determined by geographic indication) significantly reduced the effect of several parasitoids and predators with the exception of adult Coccinellidae (Mansour & al. 2012). In south Italy, T. magnum caused direct damage in horseradish cultures by injuring of plants and licking of phloem sap (D. Battaglia, pers comm., sample Potenza-2014.07.15). The nests are subterranean and often very extended, frequently reaching to a depth of 1 m. Nest entrances typically develop to big crater-like domes of ejected soil particles. When occurring in sand dunes (a typical habitat is the back of coastal sand dunes closest to sea) they excavate and maintain long-lasting trails in the sand which are V-shaped in section and up to 5 cm deep. The biggest supercolonies stretch over areas of one hectare or more, should number > 20 million workers and show a permanent exchange of broods between the nests. Single nest spots may contain up to 350 queens. Alates occurred in Italy, Germany, and the Netherlands 10 May ± 26 d [2 April - 17 June] n = 9 (arithmetic mean ± standard deviation [earliest, latest] number of observations). This is apparently the main period but there is an observation of alates in Algeria in August / September. Swarming occurred in May and June, not earlier than 2 - 3 weeks after eclosion from pupae. Most mated gynes stay in or near to the home colony seeking adoption in conspecific nests but their big bodies and well-developed flight muscles should indicate a basically good potency for dispersal flight and independent colony foundation.

Borowiec and Salata (2022) - A thermophilous species, it prefers strongly sun-exposed, open habitats as sandy beach areas, rocky coasts of natural and artificial lakes, sandy and gravely river banks, gardens and ruderal places in tourist resorts. Nests are usually under stones. In Greece, it was noted only from a coastal area in one of Dodecanese islands.

Flight Period

			X	X	X	X	X	X
Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec

Source: Seifert et al., 2017. Notes: April-June in Italy, Germany, and the Netherlands; August-September in Algeria.

Check details at Worldwide Ant Nuptial Flights Data, AntNupTracker and AntKeeping.

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

Life History Traits

Queen number: polygynous (Seifert et al., 2017) (up to 350 queens within a supercolony)
Colony type: supercolony
Maximum colony size: > 20 million (Seifert et al., 2017)

Castes

Nomenclature

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

magnum. Tapinoma magnum Mayr, 1861: 41 (q.m.) ITALY.
- Junior synonym of nigerrimum: Forel, 1876: 61.
- Status as species: Seifert et al., 2017: 123.

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

Description

Worker

Borowiec and Salata (2022) - Small to large, polymorphic: the largest workers: HL: 1.048-1.238 (mean 1.138); HW: 1.007-1.246 (mean 1.116); SL: 0.952-1.105 (mean 1.038); EL: 0.254-0.289 (mean 0.268); ML: 1.35-1.47; MW: 0.67-0.79; the smallest workers: HL: 0.778-0.857 (mean 0.831); HW: 0.683-0.781 (mean 0.747); SL: 0.706-0.811 (mean 0.770); EL: 0.198-0.209 (mean 0.205); ML: 0.92-1.03; MW: 0.43-0.52. Color. Body brown to black, gena often slightly paler than rest of head, yellowish brown, antennae and legs brown to almost black, coxa often slightly paler brown than femora, in pale specimens tibiae yellowish brown, tarsi always paler than femora yellow to yellowish brown. Head. In major workers approximately as long as wide, in minor workers 1.1 times as long as wide, widest in basal 1/3 length then softly converging anterad, occipital corners rounded, occipital margin concave. Clypeus microreticulated but shiny, triangularly extended to the front, in the middle deeply emarginate to 0.30-0.35 length of clypeus, sides of the emargination usually parallel; sides of clypeus deeply concave, posterior margin rounded, surface covered with moderately dense appressed hairs, explanate anterior margin close to median emargination with one or two pairs of erected setae and few decumbent long and short setae partly extending behind margin of clypeus and usually extending behind margins of median emargination. Head distinctly microreticulated but shiny, with moderately long and moderately dense appressed pubescence not covering head surface, erected setae absent, ventral side of head with0ut erected setae. Scape moderately elongate, in major workers 0.9 times, in minor workers as long as width of head, very thin, only slightly widened from base to apex, its surface microreticulate but shiny, with short and moderately dense appressed pubescence, erected setae absent. Funicular segments elongate, thin, first segment 2.7-2.8 times as long as wide and 1.5 times as long as second segment which is 1.9 times as long as wide, the rest of funicular segments clearly longer than broad. Eyes big, placed in the middle of frontal surface of head, almost circular, 0.24-0.25 length of head. Mandibles long, without striation, teeth of masticatory margin gradually smaller posterad. Mesosoma. Elongate, 1.9-2.2 times as long as wide, dorsally and laterally distinctly microreticulated but shiny, with short and moderately dense appressed pubescence. In lateral view pronotum and mesonotum regularly convex, propodeum forms obtuse angle, mesonotal groove moderately deep. Mesosomal dorsum lacking erected setae. Waist and gaster. Petiolar scale small, thin, hidden under protruding anterad anterior face of first gastral tergite. Gaster longer than mesosoma, tergites distinctly microreticulated sometimes tending to form transverse sculpture, surface shiny, covered with moderately long and dense appressed pubescence, first three tergites lacking erected setae, sternites with median keel. Legs. Moderately long, tibiae distinctly widened from base to apex, mid and hind tibiae with very long, sharp apical spur, first segment of tarsi longer than subsequent segments combined, surface covered with moderately long and moderately dense appressed hairs, erected setae absent, inner margin of tibiae lacking row of thorns.

Queen

Borowiec and Salata (2022) - Large : HL: 1.143; HW: 1.174; SL: 0.952; ML: 2.04; MW: 1.10; HL/HW: 0.9974; SL/HW: 0.811; ML/MW: 1.863.

Type Material

Seifert et al. (2017) - Lectotype male labelled "Savi Pisa.", "v. nigerrim. Magnum det. Mayr" [both labels in Mayr's handwriting], "Lectotype Tapinoma magnum (Mayr, 1861) des. B. Seifert 2012" and "AntWeb CASENT 0915547". One paralectotype gyne on another pin labelled "Savi Pisa.", "v. nigerrim. Magnum det. Mayr" [both labels in Mayr's handwriting] and "Paralectotype Tapinoma magnum (MAYR, 1861) des. B. Seifert 2012". Both specimens stored in NHM Wien.

References

References based on Global Ant Biodiversity Informatics

Barech G., M. Khaldi, F. Zahra Boujelal, and X. Espadaler. 2018. Diversity and structure of the ant fauna of the El Ksob dam in Algeria: new record for Aphaenogaster rupestris Forel, 1909 (Hymenoptera: Formicidae). Boletin de la Sociedad Entomologica Aragonesa (S. E. A.) 62: 253-258.
Lenoir A., and C. Galkowski. 2017. Sur la présence d’une fourmi envahissante (Tapinoma magnum) dans le Sud-Ouest de la France. Bull. Soc. Linn. Bordeaux 152, 45(4): 449-453.
Seifert B. D. D'Eustacchio, B. E. Kaufmann, M. Centorame, and M. Modica. 2017. Four species within the supercolonial ants of the Tapinoma nigerrimum complex revealed by integrative taxonomy (Hymenoptera: Formicidae). Myrmecological News 24: 123-144.