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Worldwide spread of the tropical fire ant, Solenopsis geminata (Hymenoptera: Formicidae)

February 2011
Myrmecological News 14:21-35

Authors:

Florida Atlantic University

The tropical fire ant, Solenopsis geminata (FABRICIUS, 1804), is a well-known pest in many parts of the world, where it is notorious for its potent sting. To evaluate the worldwide spread of S. geminata, I compiled and mapped published and unpublished specimen records from > 2100 sites. I documented the earliest known S. geminata records for 122 geo-graphic areas (countries, island groups, major Caribbean islands, US states, and Canadian provinces), including several areas for which I found no previously published records, e.g., Anguilla, Barbuda, Curaçao, Madagascar, Montserrat, Nebraska, Nevis, St Martin, and Vanuatu. Several New World Solenopsis species were once considered junior synonyms of S. geminata (e.g., S. gayi (SPINOLA, 1851), S. saevissima (SMITH, 1855), S. virulens (SMITH, 1858), and S. xyloni MCCOOK, 1880). Therefore, I did not map unconfirmed New World S. geminata records published before CREIGHTON's (1930) re-vision of Solenopsis from areas where these species occur, because some of these early records were likely to be based on misidentifications. Solenopsis geminata records are common through much of the New World tropics as well as parts of subtropical North America. Whereas S. geminata is certainly native to South and Central America, it may well be exotic to the southeastern US and the West Indies, introduced several hundred years ago. By 1900, S. geminata had also spread through many parts of the Old World, notably tropical Asia and Oceania.

Worldwide distribution records of Solenopsis geminata . In many areas, however, S . geminata populations have been greatly reduced or eliminated (see text).

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Myrmecological News 14 21-35 Vienna, January 2011

Worldwide spread of the tropical fire ant, Solenopsis geminata (Hymenoptera:

Formicidae)

James K. WETTERER

Abstract

The tropical fire ant, Solenopsis geminata (FABRICIUS, 1804), is a well-known pest in many parts of the world, where it

is notorious for its potent sting. To evaluate the worldwide spread of S. geminata, I compiled and mapped published and

unpublished specimen records from > 2100 sites. I documented the earliest known S. geminata records for 122 geo-

graphic areas (countries, island groups, major Caribbean islands, US states, and Canadian provinces), including several

areas for which I found no previously published records, e.g., Anguilla, Barbuda, Curaçao, Madagascar, Montserrat,

Nebraska, Nevis, St Martin, and Vanuatu. Several New World Solenopsis species were once considered junior synonyms of

S. geminata (e.g., S. gayi (SPINOLA, 1851), S. saevissima (SMITH, 1855), S. virulens (SMITH, 1858), and S. xyloni MCCOOK,

1880). Therefore, I did not map unconfirmed New World S. geminata records published before CREIGHTON's (1930) re-

vision of Solenopsis from areas where these species occur, because some of these early records were likely to be based

on misidentifications.

Solenopsis geminata records are common through much of the New World tropics as well as parts of subtropical North

America. Whereas S. geminata is certainly native to South and Central America, it may well be exotic to the southeastern

US and the West Indies, introduced several hundred years ago. By 1900, S. geminata had also spread through many parts

of the Old World, notably tropical Asia and Oceania.

In the mid-20th century, another invader from the Neotropics, the "unvanquished" fire ant, Solenopsis invicta BUREN, 1974,

began to spread around the world. Solenopsis invicta has displaced S. geminata in open and disturbed habitats in many

parts of the southern US, leaving only remnant S. geminata populations, primarily in forested areas that S. invicta does

not invade. Although S. geminata still has a much broader worldwide range, I expect S. invicta will continue to spread

and displace S. geminata in open habitats through many other parts of the tropics and subtropics.

Key words: Biogeography, biological invasion, exotic species, invasive species, stinging ant.

Myrmecol. News 14: 21-35 (online 24 June 2010)

ISSN 1994-4136 (print), ISSN 1997-3500 (online)

Received 14 January 2010; revision received 23 March 2010; accepted 29 March 2010

Prof. Dr. James K. Wetterer, Wilkes Honors College, Florida Atlantic University, 5353 Parkside Drive, Jupiter, FL 33458,

USA. E-mail: wetterer@fau.edu

Introduction

The tropical fire ant, Solenopsis geminata (FABRICIUS, 1804)

has long been one of the world's most dreaded ants due to

its powerful sting, "which it uses on the slightest provoca-

tion" (WHEELER 1910). Solenopsis geminata is originally

from the New World, where "its colonies are populous and

so numerous that it may be said to be in possession of a

large portion of the soil of the American tropics" (WHEE-

LER 1910). Like many other "tramp" ants (e.g., Paratrechina

longicornis (LATREILLE, 1802) and Tapinoma melanoce-

phalum (FABRICIUS, 1793); see WETTERER 2008, 2009),

S. geminata has spread through human commerce to many

other parts of the world.

Reports on S. geminata are replete with superlatives.

WHEELER (1914) wrote that the behavior of S. geminata

"exhibits a more bewildering diversity than that of any other

known ant, for it is not only highly carnivorous, but attends

scale insects and leaf hoppers for the sake of their saccha-

rine excrement and even collects and stores seeds in its nests

ike a true harvesting ant. In Texas I have known it to sting

young chickens to death when they happened to be con-

fined in a coop near its nest. In the same State it is help-

ful in destroying the boll weevil and other insects injurious

to cotton, but is sometimes a pest in gardens when it takes

to gnawing holes in strawberries." WHEELER (1910) wrote

that S. geminata "attacks and eats almost everything that

comes its way," and SMITH (1965) reported that S. gemi-

nata "is considered to be one of the most important pre-

dators of all the ants." Solenopsis geminata may be found

in a wider range of habitats than any other fire ant species

(TSCHINKEL 1988, 2006). For example, in Surinam, KEMPF

(1961) reported S. geminata from gardens, fields, pas-

tures, woodland, and primary forest. In addition, WHEE-

LER (1922) called S. geminata "perhaps the most dreaded

of the house ants."

In recent years, a new invader from the Neotropics, the

"unvanquished" fire ant, Solenopsis invicta BUREN, 1974,

has begun to spread around the world, displacing S. gemi-

nata both in the field and in the popular press. Nonetheless,

Figs. 1 - 4: Solenopsis geminata. (1) Head of minor worker from the Philippines; (2) lateral view of the same minor

worker; (3) head of major worker from the Philippines; (4) lateral view of the same major worker (photos by G. Alpert).

S. geminata remains a dominant global pest. In the pre-

sent study, I examine the worldwide spread of S. geminata.

Identification and taxonomy: Solenopsis geminata is

a highly polymorphic species, with a wide range of wor-

ker size within a colony (head width = 0.55 - 2.30 mm;

Figs. 1 - 4). Solenopsis geminata shows considerable vari-

ation in coloration. As a result of this variability, com-

bined with some poor taxonomic work, S. geminata has

been described repeatedly under many different names,

now designated as junior synonyms. As CREIGHTON (1930)

wrote: "S. geminata, the type of the genus, has been de-

scribed a surprising number of times. There are no less

than eleven names for this species which have been aban-

doned on the synonymic junk-heap." For example, in just

one paper, BUCKLEY (1867), a geologist untrained in ento-

mology, described S. geminata under three or more differ-

ent names. WHEELER (1902) wrote that BUCKLEY'S (1867)

"descriptions are, indeed, fearfully and wonderfully made.

With a persistency, which at times seems almost inten-

tional, the author selects for description the worthless, in-

significant features of the ant's body."

Encouragingly, CREIGHTON (1930) and TRAGER (1991)

made detailed taxonomic re-evaluations of S. geminata

nd its close relatives and their analyses largely agree on

the definition of S. geminata. CREIGHTON (1930) wrote: "It

is inevitable that such a widely distributed and abundant

ant should repeatedly appear in the literature under new

names and it is remarkable that, despite this plethora of de-

scriptions, the taxonomy of geminata has largely escaped

confusion. At various times related species have been re-

garded as variants of geminata but, during the past sixty

years there has been little doubt as to what constitutes the

typical form. Truth compels one to add that this unusual

situation is more a result of the characteristic cephalic struc-

ture of the major worker than an outcome of taxonomic

acumen." Indeed, although S. geminata minors are very dif-

ficult to distinguish from minors of related fire ants, large S.

geminata majors have several distinctive cephalic charac-

teristics that make them simple to identify. These include:

(1) a disproportionally large, almost square head with par-

allel sides, (2) a deep longitudinal groove on the front of

the head extending from a distinct medial indentation in the

vertex, (3) black mandibles, often with all teeth worn off

from use, and (4) short antennal scapes extending only about

halfway to the occiput in the largest majors (Figs. 3 - 4).

FABRICIUS (1804) described Atta geminata (= S. gemi-

nata) based on a queen from Central America. Taxa cur-

rently considered junior synonyms of S. geminata (with type

Fig. 5: Worldwide distribution records of Solenopsis geminata. In many areas, however, S. geminata populations have

been greatly reduced or eliminated (see text).

locality in parentheses) include: Myrmica paleata LUND,

1831 (Brazil); Solenopsis mandibularis WESTWOOD, 1840

(Tropical America); Atta rufa JERDON, 1851 (India); Atta

clypeata SMITH, 1858 (Mexico); Solenopsis cephalotes

SMITH, 1859 (Aru Islands, Indonesia); Myrmica mellea

SMITH, 1859 (Aru Islands); Crematogaster laboriosus

SMITH, 1860 (Bacan, Indonesia); Myrmica laevissima

SMITH, 1860 (Bacan); Diplorhoptrum drewseni MAYR, 1861

(Italy); Myrmica glaber SMITH, 1862 (Panama); Myrmica

polita SMITH, 1862 (Panama); Atta coloradensis BUCKLEY,

1867 (Texas); Atta lincecumii BUCKLEY, 1867 (Texas);

Myrmica saxicola BUCKLEY, 1867 (Texas); Solenopsis ge-

minata diabola WHEELER, 1908 (Texas); Solenopsis gemi-

nata nigra FOREL, 1908 (Costa Rica); Solenopsis eduardi

FOREL, 1912 (Colombia); Solenopsis geminata medusa

MANN, 1916 (Brazil); Solenopsis geminata galapageia

WHEELER, 1919 (Galapagos); Solenopsis edouardi bahia-

ensis SANTSCHI, 1925 (Brazil and Venezuela); and Sole-

nopsis edouardi perversa SANTSCHI, 1925 (Brazil). In ad-

dition, there is one remaining subspecies, Solenopsis gemi-

nata micans STITZ, 1912 (Seram Island, Indonesia); taxo-

nomists need to evaluate whether this taxon deserves syno-

nymy (see BOLTON 1995 for a taxonomic history of these

names).

Some taxa were designated junior synonyms of S. gemi-

nata, but were later revived from synonymy, including:

Solenopsis gayi (SPINOLA, 1851) (Chile; synonymized by

MAYR 1886; revived by EMERY 1895); Solenopsis saevis-

sima (SMITH, 1855) (Brazil; synonymized by MAYR 1865;

revived by WHEELER 1915); Solenopsis virulens (SMITH,

1858) (Brazil; synonymized by MAYR 1886; revived by

TRAGER 1991); and Solenopsis xyloni MCCOOK, 1880 (US;

synonymized by MAYR 1886; revived by WHEELER 1910).

GOETSCH (1933) synonymized Aphaenogaster santiagu-

ensis G

OETSCH, 1930 (Chile) with S. geminata, but I

have been unable to find this taxon in any reference except

GOETSCH (1930, 1933). Because SNELLING & HUNT (1975)

recognized no records of S. geminata from Chile and con-

sidered published S. geminata records from Chile (MAYR

1865) to be misidentifications of S. gayi, it seems very likely

that A. santiaguensis is a junior synonym of S. gayi. Al-

though WHEELER (1902) and others speculated that Atta

brazoensis BUCKLEY, 1867 (Texas) and Myrmica sabeana

BUCKLEY, 1867 (Texas) were also junior synonyms of S.

geminata, TRAGER (1991) conjectured that they were actu-

ally S. xyloni.

TRAGER (1991) and BOLTON (1995) considered Sole-

nopsis geminata innota SANTSCHI, 1915 (described from

Gabon, Liberia, and Zaire) to be a junior synonym of S. ge-

minata, but other researchers disagree with this designa-

tion. COLLINGWOOD & VAN HARTEN (1993) reported S.

innota from Cape Verde Islands off the coast of West Af-

rica and stated "the enlarged petiole and postpetiole link it

with S. globularia." In 2003, I collected ants in Cape Verde

and found no Solenopsis geminata. Instead, at 78 sites on

all nine inhabited islands, I collected a Solenopsis cf. glo-

bularia, a species with an enlarged petiole and post-petiole,

apparently corresponding to S. innota (J.K. Wetterer &

X. Espadaler, unpubl.). TAYLOR (2007) reported both S.

geminata and S. innota from Cameroon. TAYLOR (2007)

noted that the S. innota major had numerous characters dis-

tinguishing it from the S. geminata major, including sev-

eral pronounced teeth on the mandible and longer scapes

"almost attaining the occiput." I therefore consider S. in-

nota to be a distinct taxon from S. geminata. One possibi-

lity is that some S. innota records are actually Solenopsis

virulens (SMITH, 1858). This species, known from Brazil,

Guyana, and Peru, is "yellow, monomorphic, and about the

size of small majors of S. saevissima or S. geminata, but the

postpetiole is subglobose and very large" (KEMPF & BROWN

1968).

A third fire ant taxon has been reported from Africa as

well: Solenopsis saevissima itinerans (FOREL, 1911), de-

scribed from Tanzania and later reported from Guinea

(SANTSCHI 1914). FOREL (1911) described this taxon as

"very similar to var. Richteri FOREL, but entirely brown.

The head is rather narrow, the nodes are also narrow and

the hair is a little less abundant." It seems possible that these

ants could be S. saevissima, S. xyloni, or S. invicta.

Some taxa have changed their taxonomic status relative

to S. geminata many times. For example, FOREL (1904) de-

scribed Solenopsis geminata pylades FOREL, 1904 (Mex-

ico), but FOREL (1909) raised S. pylades to a full species.

WHEELER (1915) considered it a junior synonym of S. saevis-

sima, but FOREL (1916) again raised S. pylades to a full spe-

cies and WHEELER (1919c) again considered it a junior syno-

nym of S. saevissima. EMERY (1922) designated S. pylades

a junior synonym of S. geminata, but SANTSCHI (1923) con-

sidered it a variety of S. saevissima. TRAGER (1991) de-

signated S. pylades a junior synonym of S. xyloni, but PITTS

(2002) made S. pylades a junior synonym of S. saevissima.

Previous accounts of the New World and worldwide

distribution of S. geminata: There are many previous ac-

counts describing the geographic range of S. geminata (e.g.,

FOREL 1899, CREIGHTON 1930, SMITH 1951, COMMON-

WEALTH INSTITUTE OF ENTOMOLOGY 1958, SMITH 1965,

1979, TRAGER 1991, TABER 2000, TSCHINKEL 2006). These

accounts, however, vary considerably and are based on data

of unknown detail and questionable accuracy.

FOREL (1899) wrote that S. geminata "is the most com-

mon species of tropical America, where it is not lacking, I

think, on one square kilometer of lowland from Virginia

south to the Argentine Republic." In 1899, however, S. ge-

minata was considered the senior synonym of several other

species, including S. xyloni in North America and S. sae-

vissima and S. virulens in South America.

Using a revised, narrower concept of S. geminata,

CREIGHTON (1930) wrote that its distribution "may be sum-

marized as uniform throughout the West Indies and on the

Continent from Florida to Costa Rica. In the eastern Gulf

States its range extends inland only about a hundred to a

hundred and fifty miles [160 - 240 km] and this also ap-

pears to be true for the greater part of Texas. From Mexico

southward, however, the distribution is from coast to coast."

CREIGHTON (1930) wrote that one color variant of S. ge-

minata "extends northward from Peru through Ecuador and

western Colombia into Central America and thence through

Mexico to the Southern United States. That of the second

group begins in Northeastern Colombia and passes through

Venezuela, the Guianas and into eastern Brazil apparently

terminating about the latitude of Bahia... Except for their

greater variation in color and sculpture the members of the

first group agree closely in structure with the insular [West

Indian] geminata."

CREIGHTON (1950) wrote of S. geminata: "the main

range of this insect lies in Central America and the An-

tilles. In the United States it occurs from Texas to South

Carolina. The majority of these records come from areas on

or near the coast. As one goes inland the incidence usually

decreases except in Florida, where the insect seems to be

uniformly distributed over the entire state."

SMITH (1951) wrote that S. geminata ranged "Fla. to

Tex.; W. Indies, Mexico, Cent. Amer. and Pacific Coastal

Plain through Columbia, Ecuador, and Peru," and S. ge-

minata rufa ranged: "Fla. to Panama; also in Oriental and

Australian Regions." SMITH (1965) wrote that S. geminata

ranged "from Texas to South Carolina and Florida and

south to at least Costa Rica. It also occurs in the West In-

dies." SMITH (1979) wrote that S. geminata ranged "S.C. s.

to Fla., w. to Tex. and s. to Peru; West Indies; tropical Asia

and Pacific Islands."

The Commonwealth Agricultural Bureaux (COMMON-

WEALTH INSTITUTE OF ENTOMOLOGY 1958) published a

map of the worldwide distribution of S. geminata. In the

New World, S. geminata was shown ranging across the

southern US from southern Virginia to southern California,

through all of Mexico and Central America. In South Ame-

rica, the range of S. geminata was shown extending down

the west coast to the Tropic of Capricorn in Chile, and down

the east coast to São Paulo, except for a gap from south-

ernmost Bahia to Rio de Janeiro. In the Old World, the map

had S. geminata records scattered in Africa, Asia, Austra-

lia, and the Pacific. HILL (1974, 2008) reprinted this map

unchanged.

TRAGER (1991) wrote that S. geminata range included

the "coastal plain of the Carolinas and Georgia, Florida

west to Texas, Central America, Antilles," and northern

South America, "including the coastal areas of Northeast-

ern Brazil, west through the Guianas to the Orinoco Basin,

the western Amazon Basin and coastal areas of Peru." TRA-

GER (1991) wrote that in the Old World "S. geminata has

been introduced into both tropical Asia and Africa. The

first of these populations is now distributed from Taiwan

and India in the North, throughout the Malay archipelago

and Polynesia in the south, but the population is highly

uniform throughout this vast range, with the light reddish

coloration, relatively weak sculpture, and well-developed

mesoplural process typical of the form rufa, and may re-

sult from the successful spread of a single original intro-

duction." TRAGER (1991) wrote "the only population which

might, in my opinion, be a distinct species among the mat-

erial called S. geminata here is the western South Ameri-

can population of Colombia and Peru. This form averages

smaller in all castes than S. geminata from elsewhere, and

its sting is reputed to be more painful and to cause a pus-

tule as do stings of the S. saevissima complex. The western

population is apparently the source of the rather small S.

geminata typical of the Galapagos Islands."

TABER (2000) included a map of the worldwide distri-

bution of S. geminata. In the New World, the map showed

a range that roughly followed the accounts of CREIGHTON

(1930) and TRAGER (1991) with a few deviations: (1) great-

er inland penetration in the southeastern US (~ 400 km)

with a continuous distribution from southern North Caro-

lina across to Texas, (2) greater extension down the west

coast of South America beyond Peru, extending ~ 500 km

into Chile, (3) absence in western Mexico north of Aca-

pulco, and (4) absence in the western Amazon basin. TA-

BER (2000) also mapped scattered records of S. geminata in

the Old World in rough agreement with TRAGER's (1991)

general report, with most records spread between India

and New Guinea, including large population records in

Bangladesh, Malaysia, and New Guinea.

Most recently, TSCHINKEL (2006) included a map of the

New World range of S. geminata that was similar to the

range shown in TABER (2000), but with (1) only ~ 300 km

inland penetration in the southeastern US from southern

South Carolina to Texas, (2) only ~ 250 km extension into

Chile, and (3) less extension into western Mexico.

Because few actual specimen records accompany all

previously published reports on the range of S. geminata,

it is unclear what is based on actual data and what is sup-

position. Here, I document in detail the known worldwide

distribution of S. geminata based on specimen records.

Methods

Using published and unpublished records, I documented

the worldwide range of S. geminata. I obtained unpublished

site records from museum specimens in the collections of

the Smithsonian Institution (SI; identified by M.R. Smith),

Archbold Biological Station (ABS; identified by M. Dey-

rup), the British Natural History Museum (BMNH; iden-

tified by B. Bolton), the Museum of Comparative Zool-

ogy (MCZ; identified by S. Cover), and the Northern Ter-

ritory Economic Insect Reference Collection (NTEIRC; pro-

vided by D. Chin). In addition, I used on-line databases

with collection information on specimens by Antweb (www.

antweb.org), the Chinese Ant Database (sciencer.net/ant/

english.html), the Essig Museum (essigdb.berkeley.edu), the

Global Biodiversity Information Facility (www.gbif.org),

and the Nebraska State Insect Records (nebrecs.unl.edu).

I also received unpublished records from H. Axen (Belize,

Brazil, Costa Rica, Dominican Republic, Florida, French

Guiana, Galapagos, Guatemala, Honduras, India, Madagas-

car, Mascarene Islands, Mexico, Nicaragua, Texas, Trini-

dad, Turks & Caicos Islands, and Venezuela), M. DaSilva

(Grenadine islands), B. Hoffmann (Australia), J. Lattke (Ve-

nezuela), J. MacGown (Georgia, Mississippi), P.D. Rajan

(India), and S. Sonthichai (Thailand). Finally, I collected S.

geminata specimens in Central America, Florida, and on

numerous Pacific and Caribbean Islands.

Geographic coordinates for collection sites came from

published references, specimen labels, maps, or geography

web sites (e.g., earth.google.com, www.tageo.com, and

fallingrain.com). For older references and specimens, many

site names, particularly in Asia, are no longer in use or are

now spelled differently and I searched, not always success-

fully, to determine current names. If a site record listed a

geographic region rather than a "point locale," and I had

no other record for this region, I used the coordinates of the

largest town within the region or, in the case of small is-

lands and natural areas, the center of the region. Often, if

one source had many sites less than 10 - 20 km apart (e.g.,

STARR & al. 2007), I did not plot every site. I did not map

records of S. geminata on boats, found in newly imported

goods, or intercepted in transit by quarantine inspectors.

Published records usually included collection dates. In a

number of cases, publications did not include the collection

dates for specimens, but I was able to determine the date

based on information on the collector's travel dates or limit

the date by the collector's date of death. For example,

MAYR (1865) published S. geminata records collected by

the Novara expedition, which visited Sri Lanka in 1858 and

Tahiti in 1859. MAYR (1862) identified many specimens as

S. saevissima that MAYR (1865) re-identified as S. geminata.

Through much of its worldwide range, S. geminata is

the only fire ant known and thus records are likely to be re-

liable. In the New World, this includes all of Central Am-

erica and (before 1981, when S. invicta was first recorded)

the West Indies. In parts of the North and South America,

other fire ants occur, including S. amblychila WHEELER,

1915, S. aurea WHEELER, 1906, and S. xyloni in the south-

ern US and northern Mexico, and S. gayi, S. invicta, S.

saevissima, and S. virulens in South America. Due to mis-

identifications and transitory synonymies, some specimen

records from these areas reported as S. geminata may ac-

tually be other Solenopsis species and vice versa. In addi-

tion, worker hybrids between S. geminata and S. xyloni

(HUNG & VINSON 1977) further complicate taxonomy. To

minimize the risk of identification errors, I did not map pub-

lished S. geminata records predating CREIGHTON's (1930)

revision from New World regions where other fire ant spe-

cies occur, unless the records were confirmed in a post-

1930 publication.

Results

I compiled published and unpublished specimen records

from > 2100 sites worldwide (Fig. 5). I documented the

earliest known S. geminata records for 122 geographic ar-

eas (countries, island groups, major Caribbean islands, and

US states; Tabs. 1 - 6), including several areas for which I

found no previously published records: Anguilla, Barbuda,

Curaçao, Madagascar, Montserrat, Nebraska, Nevis, St Mar-

tin, and Vanuatu.

Unconfirmed New World records that I did not map in-

cluded all published S. geminata records from Chile (e.g.,

MAYR 1862, 1865, BERG 1890, IHERING 1894), Paraguay

(e.g., FOREL 1908), California (e.g., MAYR 1886, WHEELER

1908, ANDREWS 1916), and Virginia (e.g., FOREL 1899), as

well as a subset of records from other areas, including Ar-

gentina (e.g., BAUR 1897, BRUCH 1914), Arizona (e.g.,

WHEELER 1908), Bolivia (e.g., EMERY 1894), Brazil (e.g.,

MAYR 1865, WASMANN 1890, 1896, IHERING 1894, FOREL

1907, 1908, MANN 1916), Mexico (e.g., ANDRÉ 1893, PER-

GANDE 1893, FOREL 1899, WHEELER 1901), New Mexico

(e.g., TINSLEY 1898, CREIGHTON 1930), and North Caro-

lina (e.g., WITHERS 1898, FOREL 1899). Although WHEE-

LER (1908) described S. geminata diabola (= S. geminata)

from Texas, with additional records from Arizona, and Cali-

fornia, I did not map the records from Arizona and Cali-

fornia. KEMPF (1972) has the only post-1930 record of S.

geminata from Bolivia, but with no site listed. Rather than

mapping this record to the largest city, La Paz, in the cool

highlands, I mapped this to Cobija in the northern lowlands,

placing it nearest to records just across the border in Peru

and Brazil. Although CREIGHTON (1930), SMITH (1951),

and TRAGER (1991) all mention S. geminata in coastal Ec-

uador, and COMMONWEALTH INSTITUTE OF ENTOMOLOGY

(1958), TABER (2000), and TSCHINKEL (2006) all mapped

populations there, I found no site records for this region.

I mapped no point in this region because I suspect that

earlier authors may have simply inferred that S. geminata

populations in coastal Colombia and coastal Peru were con-

tinuous through Ecuador.

I omitted CREIGHTON'S (1930) New Mexico record be-

cause CREIGHTON (1950) omitted it. I mapped only one post-

1930 S. geminata record from New Mexico and one from

Arizona. COLE (1953) reported "one colony of what I be-

lieve represents this species was nesting beneath a stone in

very dry, level, stony soil 13 mi. N of Carlsbad, 3,300 ft,"

though this high elevation desert record seems very likely

to be a misidentification. PLOWES & al. (2009) reported

phorid flies that B. Brown collected 5 km E Portal, Ari-

zona, attacking S. geminata; unfortunately, Brown (pers.

comm.) could not locate any voucher ant specimens to ver-

ify this record.

In the case of several South American countries and US

states (Tabs. 1 - 2), the earliest record was unconfirmed and

Tab. 1: Earliest known records for Solenopsis geminata

from South and Central America and neighboring Pacific

islands. Unpublished records include collector, museum

source, and site. BMNH = Natural History Museum in Lon-

don. * = earliest record unconfirmed and may be misiden-

tification of another Solenopsis species.

≤ Earliest record

Central America ≤ 1804 (FABRICIUS 1804 – type locality)

Brazil ≤ 1831 (LUND 1831 as M. paleata)

Venezuela ≤ 1857 (H. Clark, BMNH): Tejuca

Mexico ≤ 1858 (SMITH 1858 as A. clypeata)

Panama ≤ 1861 (SMITH 1862 as M. glaber & M.

≤ polita)

Guyana ≤ 1862 (ROGER 1862*)

Uruguay ≤ 1862 (ROGER 1862*)

Surinam ≤ 1863 (ROGER 1863*)

French Guiana ≤ 1868 (RADOSZKOWSKY 1884*)

Nicaragua ≤ 1872 (T. Belt, BMNH): Chontales

Galapagos ≤ 1891 (EMERY 1893)

Bolivia ≤ 1894 (EMERY 1894*)

Cocos Islands ≤ 1898 (EMERY 1919)

Guatemala ≤ 1899 (Champion, BMNH): Guatemala

≤ City

Belize ≤ 1899 (FOREL 1900)

Colombia ≤ 1900 (FOREL 1900*)

Costa Rica ≤ 1900 (FOREL 1900)

Honduras ≤ 1920 (MANN 1922)

Ecuador ≤ 1930 (CREIGHTON 1930)

Peru ≤ 1930 (CREIGHTON 1930)

Islas Revillagigedo ≤ 1935 (WHEELER 1935)

El Salvador ≤ 1957 (BERRY & SALAZAR 1957)

not mapped, but many later records verified the presence

of S. geminata. For example, MAYR (1886) published the

earliest S. geminata records from Alabama, Florida, and

Louisiana, and though these records were not confirmed,

later records verified the presence of S. geminata in these

states (e.g., CREIGHTON 1930).

For the Old World, I mapped all published records of

S. geminata. However, I did not map African records ori-

ginally identified as S. innota because these records ap-

pear to represent a distinct taxon: Cameroon (TAYLOR

2007), Cape Verde (COLLINGWOOD & VAN HARTEN 1993),

Congo (Zaire) (SANTSCHI 1915), Gabon (SANTSCHI 1915),

and Liberia (SANTSCHI 1913).

Tab. 2: Earliest known records for Solenopsis geminata

from the USA and Canada. Abbreviations as in Tab. 1, and

MCZ = Museum of Comparative Zoology. + = no known

published record.

≤ Earliest record

+ Texas ≤ 1862 (ROGER 1862*)

+ Alabama ≤ 1886 (MAYR 1886*)

+ Florida ≤ 1886 (MAYR 1886*)

+ Louisiana ≤ 1886 (MAYR 1886*)

+ New Mexico ≤ 1897 (TINSLEY 1898*)

+ North Carolina ≤ 1899 (FOREL 1899*)

+ South Carolina ≤ 1899 (FOREL 1899*)

+ Georgia ≤ 1899 (FOREL 1899*)

+ Mississippi ≤ 1899 (FOREL 1899*)

+ Arkansas ≤ 1964 (WHITCOMB & BELL 1964 in

≤ WARREN & ROUSE 1969)

+ Manitoba ≤ 1977 (AYRE 1977)

+ Nebraska ≤ 1992 (D Ferraro, NIR): Omaha Zoo –

≤ Lied Jungle

Only 12 S. geminata site records came from latitudes

at or above 35° (Fig. 5; five New World and seven Old

World). The high latitude New World records are prob-

ably either introduced or misidentifications: the Tropical

House of Assiniboine Park Zoo in Winnipeg, Canada (49.9°

N; AYRE 1977), the Lied Jungle (billed as the "World's

Largest Indoor Rainforest") at the Omaha Zoo (41.2° N;

Tab. 2), Maquinchao, Argentina (~ 41° S; DONISTHORPE

1933), Sherman County, Texas (~ 36.3° N; O'KEEFE &

al. 2000), and Uruguay (~ 35° S; BRANDÃO 1991). The high

latitude Old World records are certainly all introduced:

Netherlands (~ 52.3° N; BOER & VIERBERGEN 2008), Kew

Gardens greenhouses, England (51.5° N; DONISTHORPE

1943), Italy (~ 42° N; MAYR 1861), Beijing, China (39.9°

N; WHEELER 1927a), Zante Island, Greece (37.7° N; COL-

LINGWOOD 1993), Mount Maunganui, New Zealand (37.6°

N; HARRIS 2005), and Cyprus (~ 35.2° N; COLLING-

WOOD & al. 1997). Most or all of these high latitude popu-

lations of S. geminata have probably been eradicated or

have died out.

Discussion

Worldwide distribution: In the New World, Solenopsis

geminata has been reported from all South and Central

American countries, the southern US from California to

Virginia, and every island group in the West Indies. How-

ever, a number of these records were identified when then

the definition of S. geminata included several other species.

Thus, a number of unconfirmed records may be based on

misidentification of these related species. Such likely mis-

identifications include all published S. geminata records

from areas beyond the northern and southern ends of its

confirmed range, including California, Virginia, and prob-

Tab. 3: Earliest known records for Solenopsis geminata

from the West Indies. Abbreviations as in Tabs. 1 and 2.

≤ Earliest record

+ Cuba ≤ 1862 (ROGER 1862)

+ Puerto Rico ≤ 1863 (ROGER 1863)

+ Virgin Islands ≤ 1878 (FOREL 1881)

+ St Lucia ≤ 1889 (G.A. Ramge, BMNH): site un-

≤ known

+ St Vincent ≤ 1892 (FOREL 1893)

+ Jamaica ≤ 1893 (ANDRÉ 1893)

+ Barbados ≤ 1896 (FOREL 1912)

+ Grenada ≤ 1897 (FOREL 1897)

+ Bahamas ≤ 1904 (WHEELER 1905)

+ Haiti ≤ 1907 (FOREL 1907)

+ Guadeloupe ≤ 1911 (WHEELER 1913)

+ Dominica ≤ 1911 (WHEELER 1913)

+ Martinique ≤ 1911 (WHEELER 1913)

+ Trinidad ≤ 1915 (URICH 1915)

+ Tobago ≤ 1918 (WHEELER 1919a)

+ Antigua 1920 (WHEELER 1923)

+ Dominican Re-

+ public

≤ 1930 (MENOZZI & RUSSO 1930)

+ Bonaire ≤ 1936 (WEBER 1948)

+ Aruba ≤ 1936 (WEBER 1948)

+ St Kitts ≤ 1937 (WEBER 1948)

+ Statia ≤ 1937 (WEBER 1948)

+ Montserrat ≤ 1991 (J.P.E.C. Darlington, MCZ):

≤ Paradise Yard

+ Cayman Islands ≤ 2004 (VARNHAM 2006)

+ Turks & Caicos ≤ 2004 (VARNHAM 2006)

+ Curacao ≤ 2004 (J.K. Wetterer, MCZ): De Savaan

+ Anguilla ≤ 2006 (J.K. Wetterer, MCZ): Meads Bay

+ St Martin ≤ 2006 (J.K. Wetterer, MCZ): Pic Paradis

+ Barbuda ≤ 2007 (J.K. Wetterer, MCZ): Codrington

+ Nevis ≤ 2007 (J.K. Wetterer, MCZ): Cane Garden

ably Arizona and New Mexico in the north and Chile, Pa-

raguay, and probably Argentina and Uruguay in the south.

My specimen record map for S. geminata (Fig. 5) in

the New World differs from the range maps of COMMON-

WEALTH INSTITUTE OF ENTOMOLOGY (1958), TABER (2000),

Tab. 4: Earliest known records for Solenopsis geminata from

Asia and neighboring islands. Abbreviation as in Tab. 1.

≤ Earliest record

India ≤ 1851 (JERDON 1851 as S. geminata rufa)

Sri Lanka ≤ 1858 (MAYR 1865)

Indonesia ≤ 1859 (SMITH 1859 as S. cephalotes &

≤ M. mellea)

Philippines ≤ 1862 (MAYR 1862 misidentified as S.

≤ saevissima)

Burma/Myanmar ≤ 1885 - 1887 (EMERY 1889)

Singapore ≤ 1897 (MAYR 1897)

Christmas

Island

≤ 1915 (CRAWLEY 1915 as S. geminata rufa)

Malaysia ≤ 1919 (WHEELER 1919b as S. geminata rufa)

Laos ≤ 1920 (SANTSCHI 1920 as S. geminata rufa)

China ≤ 1927 (WHEELER 1927a as S. geminata rufa)

Vietnam ≤ 1927 (WHEELER 1927b as S. geminata rufa)

Hong Kong ≤ 1928 (WHEELER 1928)

Macao ≤ 1928 (WHEELER 1928)

Thailand ≤ 1928 (Hillman, BMNH): Bangkok

Papua New

Guinea

≤ 1935 (WHEELER 1935 as S. geminata rufa)

Bangladesh ≤ 1958 (COMMONWEALTH INSTITUTE OF

≤ ENTOMOLOGY 1958)

Japan ≤ 1967 (KIRITANI & MORIMOTO 2004)

Taiwan ~ 1985 (CHEN & al. 2005)

UAE ≤ 1995 (COLLINGWOOD & al. 1997)

Hainan Island ≤ 1998 (FELLOWES & HAU 2001)

Brunei ≤ 1999 - 2000 (EGUCHI & YAMANE 2003)

Cocos (Keeling)

Island

≤ 2005 (NEVILLE & al. 2008)

and TSCHINKEL (2006) in many respects. The COMMON-

WEALTH INSTITUTE OF ENTOMOLOGY (1958) map appears

to approximate the combined range of S. geminata, S. xy-

loni, S. saevissima, and S. gayi, no doubt due to misidenti-

fications in the southwestern US and Mexico in the north

and in Argentina, Brazil, and Chile in the south. The maps

of TABER (2000) and TSCHINKEL (2006) omit published

records from western Mexico north of Acapulco, e.g.,

CREIGHTON's (1930) record from Guadalajara, Jalisco. On

the west coast of South America, I found S. geminata rec-

ords extending only into northern Peru, in agreement with

CREIGHTON (1930), SMITH (1979), and TRAGER (1991),

not down into Chile as in TABER (2000) and TSCHINKEL

(2006). Also, the TABER (2000) and TSCHINKEL (2006)

Tab. 5: Earliest known records for Solenopsis geminata

from Oceania. Abbreviations as in Tabs. 1 and 2.

≤ Earliest record

+ Society Islands ≤ 1859 (MAYR 1865)

+ Australia ≤ 1863 (ROGER 1863)

+ New Zealand ≤ 1876 (MAYR 1876)

+ Hawaii ≤ 1879 (BLACKBURN & KIRBY 1880)

+ New Caledonia ≤ 1882 (EMERY 1883)

+ Mariana Islands ≤ 1894 (collector unknown, BMNH):

≤ Ladrone

+ Cook Islands ≤ 1914 (WILSON & TAYLOR 1967)

+ Samoa ≤ 1916 (H. Swale, BMNH): Apia

+ Tuamotu Islands ≤ 1925 (CHEESMAN & CRAWLEY 1928)

+ Austral Islands ≤ 1934 (WILSON & TAYLOR 1967)

+ Line Islands ≤ 1934 (WHEELER 1936)

+ Palau ≤ 1936 (CLOUSE 2007)

+ FSM ≤ 1950 (CLOUSE 2007)

+ Marshall Islands ≤ 1953 (CLOUSE 2007)

+ Tonga ≤ 1956 (WILSON & TAYLOR 1967)

+ Banaba ≤ 1957 (CLOUSE 2007)

+ Solomon Islands ≤ 1962 (GREENSLADE 1969)

+ Tuvalu ≤ 1976 (P. Maddison, BMNH): Funafuti

+ Gambier Islands ≤ 1996 (MORRISON 1997)

+ Marquesas

+ Islands

≤ 1996 (MORRISON 1997)

+ Fiji ≤ 1997 (WATERHOUSE 1997)

+ Gilbert Islands ≤ 1999 (CLOUSE 2007)

+ Vanuatu ≤ 1999 (E. Tabi, MCZ): Sama

maps did not include records from Peru and Ecuador east of

the Andes (e.g., PARDO VARGAS 1964, ESCALANTE-GUTI-

ÉRREZ 1975, TOBIN 1995, PLOWES & al. 2009). In eastern

South America, I found coastal records extended farther

south than indicated by TABER (2000) and TSCHINKEL

(2006), with many records not only throughout Bahia (e.g.,

FOWLER & DELABIE 1995, SANTOS & al. 1999, SANTANA-

REIS & SANTOS 2001, PITTS 2002), but also farther south,

in Espiritu Santo (PITTS 2002), Minas Gerais (FOWLER & al.

1995, NASCIMENTO 2005), and São Paulo (H. Axen, pers.

comm.). TABER (2000) included a record from Rio de Ja-

neiro, and though there are published records from here

(MAYR 1865) and further south (IHERING 1894, FOREL

1908), I did not map these unconfirmed records because

they are likely to be based on misidentifications.

Tab. 6: Earliest known records for Solenopsis geminata

from Europe, Africa, and neighboring islands. Abbrevia-

tion as in Tab. 1.

+ Europe ≤ Earliest record

+ Italy ≤ 1861 (MAYR 1861 as D. drewseni)

+ England ≤ 1932 (DONISTHORPE 1943)

+ Greece ≤ 1982 - 1988 (COLLINGWOOD 1993)

+ Cyprus ≤ 1997 (COLLINGWOOD & al. 1997)

+ Netherlands ≤ 1992 (BOER & VIERBERGEN 2008)

+ Africa

+ Senegal ≤ 1862 (ROGER 1862)

+ Mascarene

+ Islands

~ 1901 (D'EMMEREZ DE CHARMOY 1921

≤ in MOUTIA & MAMET 1946)

+ Congo Republic) ≤ 1909 (SANTSCHI 1909)

+ Sierra Leone ≤ 1915 (BACOT 1916)

+ Guinea ≤ 1935 (SANTSCHI 1939 as S. geminata

≤ nigra)

+ Equatorial Guinea ≤ 1939 - 1940 (MENOZZI 1942)

+ Nigeria ≤ 1969 (BOLTON 1973)

+ Madagascar ≤ 1981 (J.M. Wilson, BMNH): Ambilobe

+ South Africa ≤ 1990 (PRINS & al. 1990)

+ Canary Islands ≤ 1997 (HÔGMO 2003)

+ Cameroon ≤ 2001 (TAYLOR 2007)

In the Old World, S. geminata is widespread through

tropical and subtropical Asia, Australia, and Oceania. The

documented range of S. geminata in Africa is much more

limited, and many S. geminata records from Africa appear

to be a different species. Finally, there are a few indoor rec-

ords from temperate Europe and North America. My new

S. geminata distribution map (Fig. 5) includes many Old

World records not found on TABER's (2000) map, e.g.,

England, Greece, Cyprus, Italy, Nigeria, Cameroon, Repub-

lic of Congo, Zaire, Vietnam, Burma, New Caledonia,

Tuvalu, Solomon Islands, Fiji, Caroline Islands, Marshall

Islands, and New Zealand. Many S. geminata records from

Australia and New Zealand came from port areas and from

plant nurseries, e.g., the Illparpa Nursery in Alice Springs

(2005; NTEIRC). Control efforts in Australia and New

Zealand have successfully exterminated numerous isolated

local populations of S. geminata (B. Hoffmann, pers. comm.).

In Australia, S. geminata populations are widespread only

in the northern "Top End" region of Northern Territory.

Native versus exotic New World range: Solenopsis

geminata is originally from the New World tropics and

subtropics. However, the extent of the native range of S.

geminata in the New World remains unclear. Solenopsis

geminata is almost certainly native to South America, Cen-

tral America, and Mexico, and most authors consider S.

geminata as native to the southeastern US (e.g., WOJCIK

& al. 1976, JOUVENAZ & al. 1977, HÖLLDOBLER & WILSON

1990, TSCHINKEL 2006). SMITH (1930) listed S. geminata

as an exotic in Florida, but later SMITH (1965) considered

S. geminata to be a native species in the eastern US. TRA-

GER (1991) wrote: "S. geminata is apparently native to the

southeast coastal plain and Florida to Texas ... south through

Central America to Northern South America ... Popula-

tions of the Antilles and Galápagos (and possibly the South-

eastern U.S.A.) are probably introduced, but have been in

these areas for several centuries." DEYRUP & al. (2000)

proposed that S. geminata in Florida might be a mix of

native and exotic populations. In fact, this may be true in

many other parts of the world as well.

In the southeastern US, populations of S. geminata

appear to have more parasites than do populations of the

exotic Solenopsis invicta, supporting the hypothesis that S.

geminata is native to this region. For example, JOUVENAZ

& al. (1977) surveyed Solenopsis parasites in the southe-

astern US, and found a 140 times higher rate of micro-

sporidia infection in S. geminata colonies than in S. in-

victa colonies. In northern Florida, MCINNES & TSCHINKEL

(1996) found mermithid nematode infection rate of 16%

among S. geminata queens and 0% among S. invicta queens.

In Florida, however, no parasitoid phorid flies naturally at-

tack S. geminata, in contrast to Texas where 6 - 8 species

of phorids attack S. geminata (S. Porter, pers. comm.), sug-

gesting that S. geminata is not native to Florida.

Some authors have considered S. geminata as exotic to

the West Indies. WHEELER (1908) reported S. geminata as

"transported to the Antilles." TRAGER (1991) considered

the West Indian populations as "probably introduced." New-

ly introduced species may show population explosions, so

population explosions of S. geminata in the West Indies

could indicate that this species is exotic to this region. WHEE-

LER (1926) proposed that Formica omnivora LINNAEUS,

1758, a voracious ant that besieged several tropical West

Indian islands in the 16th to 18th centuries, was most prob-

ably S. geminata. In summarizing early reports on F. om-

nivora in the West Indies, MORLEY (1953) was less cir-

cumspect concerning the identity of this pest: "In 1760 it

was seriously debated whether the island of Barbados should

be abandoned, because of the sudden and disastrous ap-

pearance of a plague of "Fire Ants," Solenopsis geminata.

Their large aphids and scale insect herds did such damage

to the sugar-cane crops that the island, formerly a flourish-

ing colony, was driven to the verge of bankruptcy. The

same ants appeared in Martinique in 1763, the year after its

capture from the French by the British Admiral Rodney.

Seven years later the island of Grenada, 170 miles to the

south, suffered a similar fate." Population explosions of this

ant, however, may have been related not to recent intro-

duction, but instead to habitat changes associated with hu-

man settlement or to the introduction of a new mutualist

aphid, scale insect, or other Hemiptera.

On-going research on the genetic diversity of S. gemi-

nata at sites around the world should help to resolve ques-

tions concerning the native range and invasion history of

this species. For example, preliminary genetic results sug-

gest that S. geminata populations in the southeastern US

are exotic (AXEN 2008, H.J. Axen, pers. comm.). LONGINO

(2005) noted that in Costa Rica, S. geminata has "a "red

form" that is more abundant in open areas and a "black

form" that prefers forested areas."

Community dominance: In many parts of its range, S.

geminata is a dominant species in both natural and dis-

turbed ecosystems, tending plant-feeding Hemiptera and

acting as an important predator and seed-disperser (e.g.,

JEANNE 1979). For example, in Mexico, RISCH & CARROLL

(1986) considered S. geminata to be a keystone species,

because its presence or absence had a tremendous effect

on both the arthropod community through predation and

on the plant community through seed dispersal (RISCH &

CARROLL 1986, HORVITZ & SCHEMSKE 1986). RISCH &

CARROLL (1986) found that S. geminata in Mexico har-

vested small seeds and when common, S. geminata could

reduce the abundance of many weedy plants, particularly

grasses. In northeastern Mexico, FLORES-MALDONADO &

al. (1999) found that S. geminata dominated disturbed oak

and pine forests, making up the vast majority of ants col-

lected in these habitats (91.7% and 96.2%, respectively).

In Honduras, WYCKHUYS & O'NEIL (2007) found that S.

geminata made up more than 50% of ants collected in sub-

sistence maize fields.

Solenopsis geminata is also known to attack the hatch-

lings of birds & reptiles (e.g., STODDARD 1931, TRAVIS

1938, 1941, KROLL & al. 1973, MRAZEK 1974, MAES &

MACKAY 1993). WETTERER (2006) found that S. geminata

was the most common ant on an important sea turtle nesting

beach in Tortuguero, Costa Rica, where earlier research-

ers documented ants preying on sea turtle eggs and hatch-

lings. Solenopsis geminata was the only species present

that was likely to pose a significant threat to sea turtles.

Because of the very high numbers of S. geminata on Tor-

tuguero beach, the impact of these ants on hatchling sea

turtles could be substantial, particularly on hatchlings stung

as they exit their nests.

In agricultural areas, S. geminata may be a serious pest.

For example, on Java and Mauritius, ORDELHEIDE (1929)

and D'EMMEREZ DE CHARMOY (1930) reported S. gemi-

nata as a serious pest harvesting planted tobacco seeds.

CHERIAN (1933) reported S. geminata destroying seedlings

and burrowing into the roots of marijuana plants. STAHL &

SCARAMUZZA (1929) reported S. geminata tending mealy-

bugs on sugar.

In some cases, S. geminata is considered beneficial.

For example, in Sri Lanka, ROTHNEY (1889) reported that

S. geminata were deliberately introduced into warehouses

to control termites. In Malaysia, SIVAPRAGASAM & CHUA

(1997) found S. geminata was the major predator on cab-

bage pests.

Competition with other ants: Solenopsis geminata of-

ten shows a mutually exclusive distribution with other do-

minant ant species. For example, WHEELER (1910) reported

this pattern with S. geminata and the African big-headed

ant, Pheidole megacephala on two Caribbean islands: "I

devoted ten days to a careful study of the ant-fauna of the

little island of Culebra off the eastern coast of Porto Rico

without seeing a single specimen of Ph. megacephala. This

island is, however, completely overrun with a dark vari-

ety of the vicious fire-ant (Solenopsis geminata). One day,

on visiting the island of Culebrita, which is separated by

a shallow channel hardly a mile in width from the eastern

coast of Culebra, I was astonished to find it completely

overrun with Ph. megacephala. This ant was nesting un-

der every stone and log, from the shifting sand of the sea-

beach to the walls of the light-house on the highest point

of the island. The most careful search failed to reveal the

presence of any other species, though the flora and physical

conditions are the same as those of Culebra. It is highly

probable that Ph. megacephala, perhaps accidentally intro-

duced from the island of St. Thomas a few miles to the

east, had exterminated all the other ants which must have

previously inhabited Culebrita. The absence of megacepha-

la on Culebra is perhaps explained by the presence of the

equally prolific and pugnacious fire-ant" (WHEELER 1910).

WETTERER & O'HARA (2002) found a similar pattern on

the Dry Tortugas, the outermost Florida Keys. On Garden

Key, S. geminata was the dominant ant, occurring at 70%

of bait stations, usually with several hundred workers on

each bait card. Many visitors on Garden Key reported be-

ing stung on the feet by these ants. Although P. mega-

cephala may have occurred at one time on Garden Key,

we found none. In contrast, we found no S. geminata on any

other key in the Dry Tortugas. Instead, on Loggerhead

Key and Bush Key, P. megacephala was the dominant ant.

In Laguna del Tigre National Park, BESTELMEYER &

al. (2000) collected S. geminata in all surveyed areas, but

"in the grassland transect, Solenopsis geminata was ex-

tremely dominant." In the grasslands, Pheidole sp. was the

most common ant at tuna baits 10 and 30 min after place-

ment. From 50 min on, however, S. geminata was the in-

creasingly dominant species present and by 130 min, Phei-

dole sp. was completely displaced and no longer found at

the baits.

Solenopsis invicta versus Solenopsis geminata: In

the 20th century, another Solenopsis fire ant has begun to

spread around the world: S. invicta. This species has pro-

ven to be an even greater pest than S. geminata. For exam-

ple, TSCHINKEL (2006) noted that the stings of S. invicta

"have more severe and longer-term effects than those of

S. geminata." Originally from South America, S. invicta

arrived in Alabama by ship sometime before 1945 (BUREN

& al. 1974). Since then, S. invicta has spread across the

US from Texas to Virginia in the southeast and California

in the west, causing widespread ecological and economic

damage (WOJCIK & al. 2001). This dreaded ant is now

spreading through the West Indies (WETTERER & DAVIS

2010) and has recently arrived in Asia (e.g., CHEN & al.

2005, ZHANG & al. 2007).

When it invades, S. invicta often displaces S. geminata,

particularly in habitats preferred by both species: open, gras-

sy areas. As a result, S. geminata has largely disappeared

from much of its former range in the southeastern US (WOJ-

CIK & al. 1976). For example, TSCHINKEL (2006) wrote that

S. geminata "before S. invicta spread into Florida, was one

of the most common ants there. It tolerated a wider range

of habitats... including some types of woodland not pre-

ferred by S. invicta. As S. invicta spread, the two species

occurred side by side for a while, but within a few years, S.

geminata could be found only as enclaves in more wooded

locations." In Florida, PORTER (1992) found S. geminata

at 83% of roadside sites where S. invicta were absent, but

only 7% of sites where S. invicta was present. Many cli-

mate models predict that S. invicta should be able to in-

vade many additional regions in both the New World and

Old World now occupied by S. geminata (e.g., see KOR-

ZUKHIN & al. 2001, MORRISON & al. 2004, SUTHERST &

MAYWALD 2005). It seems likely that Solenopsis gemi-

nata is also excluded from many parts of South America

by S. invicta and other resident fire ants.

With S. invicta receiving so much media attention, it

appears that some recent reports in the popular press of S.

invicta from parts of Asia (e.g., Malaysia, Singapore, Phil-

ippines) may actually be based on misidentifications of the

long-resident S. geminata. In working to mitigate the nega-

tive impacts of S. geminata, S. invicta, and other fire ants

around the world, it will be important to distinguish between

these ants, and recognize both their similarities and their

differences.

Acknowledgements

I thank M. Wetterer, J. Trager, S. Porter, B. Hoffmann, and

H. Axen for comments on this manuscript; S. Cover for

help, encouragement, and ant identification; B. Bolton

(BMNH), S. Cover (MCZ), M. Deyrup (ABS), and T.

Schultz (SI) for help with their respective ant collections;

H. Axen, D. Chin, M. DaSilva, B. Hoffmann, J. Lattke, J.

MacGown, P.D. Rajan, and S. Sonthichai for supplying un-

published records; W. O'Brien for GIS help; D.P. Wojcik

and S.D. Porter for compiling their FORMIS bibliogra-

phy; C. Scheid and R. Pasos of the FAU library for pro-

cessing so many interlibrary loans; Florida Atlantic Univer-

sity, the National Science Foundation (DEB-0515648), and

the National Geographic Society for financial support.

Zusammenfassung

Die tropische Feuerameise, Solenopsis geminata (FABRI-

CIUS, 1804), ist eine in vielen Teilen der Welt als Lästling

und Schädling bekannte Art und wird wegen ihres schmerz-

haften Stichs gefürchtet. Um die weltweite Verbreitung von

S. geminata abzuschätzen, habe ich veröffentlichte und un-

veröffentlichte Nachweise von > 2100 Fundorten zusam-

mengetragen. Ich dokumentiere die frühesten bekannten

Nachweise der Art für 122 geographische Gebiete (Län-

der, Inselgruppen, große Karibische Inseln, US-Bundes-

staaten und kanadische Provinzen), einschließlich einiger,

für die ich keine bisher veröffentlichten Nachweise gefun-

den habe, beispielsweise Anguilla, Barbuda, Curaçao, Ma-

dagaskar, Montserrat, Nebraska, Nevis, St Martin und Va-

nuatu. Mehrere Solenopsis-Arten der Neuen Welt wurden

früher als Juniorsynonyme von S. geminata betrachtet, z.B.

S. gayi (SPINOLA, 1851), S. saevissima (SMITH, 1855), S.

virulens (SMITH, 1858) und S. xyloni MCCOOK, 1880. Des-

halb habe ich unbestätigte Meldungen von S. geminata von

vor der Gattungsrevision von CREIGHTON (1930) für Regi-

onen der Neuen Welt, in denen jene Arten vorkommen,

nicht berücksichtigt – einige dieser frühen Meldungen ba-

sieren wahrscheinlich auf Fehlbestimmungen.

Zahlreiche Nachweise von Solenopsis geminata liegen

für weite Teile der Tropen der Neuen Welt sowie auch für

Teile des subtropischen Nordamerika vor. Die Art ist sicher-

lich in Süd- und Mittelamerika heimisch, aber könnte in den

südöstlichen USA und den Westindischen Inseln exotisch

sein, wobei die Einschleppung mehrere Jahrhunderte zu-

rückliegen könnte. Bereits 1900 war die Art auch in vielen

Teilen der Alten Welt verbreitet, einschließlich des tropi-

schen Asiens und Ozeaniens.

In der Mitte des Zwanzigsten Jahrhunderts begann eine

andere invasive Art aus den Neotropen, die "unbesiegte"

Feuerameise, Solenopsis invicta BUREN, 1974, ihre glo-

bale Ausbreitung. Solenopsis invicta hat S. geminata in of-

fenen und gestörten Habitaten in großen Teilen der südli-

chen USA ersetzt; Restpopulationen von S. geminata konn-

ten vor allem in bewaldeten Gebieten überleben, die S.

invicta nicht besiedelt. Obwohl S. geminata derzeit noch

eine weitaus größere globale Verbreitung hat, erwarte ich,

dass S. invicta seine Ausbreitung fortsetzen und S. gemina-

ta in offenen Habitaten vieler Teile der Tropen und Sub-

tropen ersetzen wird.

References

ANDRÉ, E. 1893: Description de quatre espèces nouvelles de four-

mis d'Amérique. – Revue d'Entomologie Caen 12: 148-152.

ANDREWS, H. 1916: Ants caught on a trip to California (Hym.).

– Entomological News 27: 421-423.

AXEN, H. 2008: Phylogenetic analysis of range expansion of the

fire ant Solenopsis geminata. – Abstracts for the NAS – IUSSI

Breakout Meeting at Arecibo, Puerto Rico. <http://iussi.bees.net/

meetings/2008proceeding.pdf>, retrieved on 10 January 2010.

AYRE, G.L. 1977: Exotic ants in Winnipeg. – Manitoba Ento-

mologist 11: 41-44.

BACOT, A.W. 1916: Report of the Entomological Investigation

undertaken for the Commission for the year, August 1914 to

July 1915. – Report of the Yellow Fever Commission (West

Africa) 3: 1-191.

BAUR, G. 1897: New observations on the origin of the Galapagos

Islands, with remarks on the geological age of the Pacific Ocean.

– The American Naturalist 31: 864-896.

BERG, C. 1890: Enumeración sistemática y sinonimica de los for-

micidos argentinos, chilenos y uruguayos. – Anales de la Socie-

dad Cientifica Argentina (Buenos Aires) 29: 5-43.

BERRY, P.A. & SALAZAR, V.M. 1957: Lista de insectos clasifi-

cados de El Salvador. – Boletin Técnico (El Salvador. Minis-

terio de Agricultura y Ganadería) 21: 1-136.

BESTELMEYER, B.T., ALONSO, L.E. & SNELLING, R.R. 2000: The

ants (Hymenoptera: Formicidae) of Laguna del Tigre National

Park, Peten, Guatemala. – RAP Bulletin of Biological Assess-

ment 16: 75-83.

BLACKBURN, T. & KIRBY, W.F. 1880: Notes on species of acu-

leate Hymenoptera occurring in the Hawaiian Islands. – Ento-

mologists Monthly Magazine 17: 85-89.

BOER, P. & VIERBERGEN, B. 2008: Exotic ants in the Netherlands

(Hymenoptera: Formicidae). – Entomologische Berichten 68:

121-129.

BOLTON, B. 1973: The ant genera of West Africa: a synonymic

synopsis with keys (Hymenoptera: Formicidae). – Bulletin of

the British Museum (Natural History) Entomology 27: 317-368.

BOLTON, B. 1995: A new general catalogue of the ants of the

world. – Harvard University Press, Cambridge, MA, 504 pp.

BRANDÃO, C.R.F. 1991: Adendos ao catálogo abreviado das for-

migas da região Neotropical (Hymenoptera: Formicidae). – Re-

vista Brasileira de Entomologia 35: 319-412.

BRUCH, C. 1914: Catálogo sistemático de los coleópteros de la

República Argentina. Pars III. – Revista del Museo de La Plata

19: 303-39.

BUCKLEY, S.B. 1867: Descriptions of new species of North Am-

erican Formicidae. – Proceedings of the Entomological Soci-

ety of Philadelphia 6: 335-350.

BUREN, W.F., ALLEN, G.E., WHITCOMB, W.H., LENNARTZ, F.E. &

WILLIAMS, R.N. 1974: Zoogeography of the imported fire ants.

– Journal of the New York Entomological Society 82: 113-124.

CHEESMAN, L.E. & CRAWLEY, W.C. 1928: A contribution towards

the insect fauna of French Oceania – Part III. Formicidae. –

Annals & Magazine of Natural History (10)2: 514-525.

CHEN, Y.F., CHANG, H.C. & CHAO, C.M. 2005: Fire ant, a new

hazard to military camps in Taiwan. – Journal of Medical Sci-

ence 25: 161-166.

CHERIAN, M.C. 1933: Pests of ganja (Cannabis sativa). – Madras

Agricultural Journal 20 (7): 259-265.

COMMONWEALTH INSTITUTE OF ENTOMOLOGY 1958: Solenopsis

geminata (FABRICIUS). – Commonwealth Agricultural Bureaux

Distribution Maps of Pests 95: 1-2.

CLOUSE, R.M. 2007: The ants of Micronesia (Hymenoptera: For-

micidae). – Micronesica 39: 171-295.

COLE, A.C. Jr. 1953: Studies of New Mexico ants. VI. The gene-

ra Monomorium, Solenopsis, Myrmecina, and Trachymyrmex

(Hymenoptera: Formicidae). – Journal of the Tennessee Aca-

demy of Science 28: 299-300, 316.

COLLINGWOOD, C.A. 1993: A comparative study of the ant fauna

of five Greek islands. – Biologia Gallo-hellenica 20: 191-197.

COLLINGWOOD, C.A., TIGAR, B.J. & AGOSTI, D. 1997: Introduced

ants in the United Arab Emirates. – Journal of Arid Environ-

ments 37: 505-512.

COLLINGWOOD, C.A. & VAN HARTEN, A. 1993: The ants (Hyme-

noptera: Formicidae) of the Cape Verde Islands. – Courier For-

schungsinstitut Senckenberg 159: 411-414.

CRAWLEY, W.C. 1915: Ants from north and south-west Australia

(G.F. Hill, Rowland Turner) and Christmas Island, Straights

Settlements. – Part II. – Annals and Magazine of Natural His-

tory (8)15: 232-239.

CREIGHTON, W.S. 1930: The New World species of the genus

Solenopsis (Hymenoptera: Formicidae). – Proceedings of the

American Academy of Arts & Sciences 66: 39-151.

CREIGHTON, W.S. 1950: The ants of North America. – Bulletin

of the Museum of Comparative Zoology 104: 1-585.

D'EMMEREZ DE CHARMOY, D. 1930: Insect pests in Mauritius in

1928 (summary). – Review of Applied Entomology 18: 559.

DEYRUP, M., DAVIS, L. & COVER, S. 2000: Exotic ants in Florida.

– Transactions of the American Entomological Society 126:

293-326.

DONISTHORPE, H. 1933: On a small collection of ants made by

Dr. F.W. Edwards in Argentina. – Annals and Magazine of

Natural History (1)12: 532-538.

DONISTHORPE, H. 1943: Myrmecological gleanings. – Proceedings

of the Royal Entomological Society of London (B) 12: 115-116.

EGUCHI, K. & YAMANE, S. 2003: Species diversity of ants (Hyme-

noptera, Formicidae) in the lowland rainforest, northwestern

Borneo. – New Entomologist 52: 49-59.

EMERY, C. 1883: Alcune formiche della Nuova Caledonia. – Bol-

lettino della Società Entomologica Italiana 15: 145-151.

EMERY, C. 1889: Formiche di Birmania e del Tenasserim rac-

colte da Leonardo Fea (1885-87). – Annali del Museo Civico

di Storia Naturale 27: 485-520.

EMERY, C. 1893: Notice sur quelques fourmis des îles Galapagos.

– Annales de la Société Entomologique de France 62: 89-92.

EMERY, C. 1894: Studi sulle formiche della fauna Neotropica. –

Bollettino della Società Entomologica Italiana 26: 137-241.

EMERY, C. 1895: Deuxième note sur les fourmis du Chili. – Ac-

tes de la Société Scientifique du Chili 5: 10-18.

EMERY, C. 1919: Formiche dell'Isola Cocos. – Rendiconto delle

Sessioni della Reale Accademia delle Scienze dell'Istituto di

Bologna 23: 36-40.

EMERY, C. 1922: Hymenoptera, Fam. Formicidae, subfam. Myr-

micinae. – Genera Insectorum 174B: 95-20.

ESCALANTE GUTIÉRREZ, J.A. 1975: Hormigas de la provincia de

la Convención, Cusco. – Revista de Peruana Entomologia 18:

125-126.

FABRICIUS, J.C. 1804: Systema Piezatorum. – Carolum Reichard,

Brunsviga, 439 pp.

FELLOWES, J.R. & HAU, B.C.H. 2001: Report of a rapid biodi-

versity assessment at Nanweiling Forest Area, Central Hai-

nan, 1 to 2 April 1998. – South China Forest Biodiversity Sur-

vey Report Series 1: 1-9.

FLORES-MALDONADO, K.Y., PHILLIPS, S.A. Jr. & SÁNCHEZ-RAMOS,

G. 1999: The myrmecofauna (Hymenoptera: Formicidae) along

an altitudinal gradient in the Sierra Madre Oriental of North-

eastern Mexico. – The Southwestern Naturalist 44: 457-461.

FOREL, A. 1881: Die Ameisen der Antille St. Thomas. – Mittei-

lungen des Münchner Entomologischen Vereins 5: 1-16.

FOREL, A. 1893: Formicides de l'Antille St. Vincent, récoltées par

Mons. H. H. Smith. – Transactions of the Entomological So-

ciety of London 1893: 333-418.

FOREL, A. 1897: Quelques Formicides de l'Antille de Grenada

récoltés par M. H. H. Smith. – Transactions of the Entomolo-

gical Society of London 1897: 297-300.

FOREL, A. 1900: Biologia Centrali-Americana; or, contributions

to the knowledge of the fauna and flora of Mexico and Central

America. Insecta. Hymenoptera. 3. Formicidae. – R.H. Porter,

London, 160 pp.

FOREL, A. 1904: Fourmis du Musée de Bruxelles. – Annales de

la Société Entomologique de Belgique 48: 168-177.

FOREL, A. 1907: Formiciden aus dem Naturhistorischen Museum

in Hamburg. – Mitteilungen aus dem Naturhistorischen Museum

in Hamburg 24: 1-20.

FOREL, A. 1908: Ameisen aus Sao Paulo (Brasilien), Paraguay,

etc. Gesammelt von Prof. Herm. v. Ihering, Dr. Lutz, Dr. Fie-

brig, etc. – Verhandlungen der Kaiserlich-Königlichen Zoolo-

gisch-Botanischen Gesellschaft in Wien 58: 340-418.

FOREL, A. 1909: Ameisen aus Guatemala, usw., Paraguay und

Argentinien (Hym.). – Deutsche Entomologische Zeitschrift

1909: 239-269.

FOREL, A. 1911: Fourmis d'Afrique et d'Asie. 1. Fourmis d'Afri-

que surtout du Musee du Congo Belge. – Revue de Zoologie

Africaine 1: 274-283.

FOREL, A. 1912: Formicides Néotropiques. Part IV. 3me sous-

famille Myrmicinae Lep. – Mémoires de la Société Entomo-

logique de Belgique 20: 1-32.

FOREL, A. 1916: Fourmis du Congo & d'autres provenances ré-

coltées par MM. Hermann Kohl, Luja, Mayné, etc. – Revue

Suisse de Zoologie 24: 397-460.

FOWLER, H.G., CAMPIOLO, S., PESQUERO, M.A. & PORTER, S.D.

1995: Notes on a southern record for Solenopsis geminata (Hy-

menoptera: Formicidae). – Iheringia, Série Zoologia 79: 173.

FOWLER, H.G. & DELABIE, J.H.C. 1995: Resource partitioning

among epigaeic and hypogaeic ants (Hymenoptera: Formici-

dae) of a Brazilian cocoa plantation. – Ecologia Austral 5:

117-124.

GOETSCH, W. 1930: Expediciones informativas por el pais para

el estudio de la Fauna chilena. – Anales de la Universidad de

Chile Ser. 2, 8 (2): 1437-1484.

GOETSCH, W. 1933: Chilenische Wüsten-, Steppen- und Wald-

Ameisen. – Sitzungsberichte der Gesellschaft für Morphologie

und Physiologie in München 42: 27-35.

GREENSLADE, P.J.M. 1969: Land fauna: insect distribution patterns

in the Solomon Islands. – Philosophical Transactions of the

Royal Society B 255: 271-284.

HARRIS, R.J. 2005: Invasive ant risk assessment. Solenopsis ge-

minata. – Landcare Research Report to the Ministry of Agri-

culture and Forestry. Nelson, New Zealand, 67 pp.

HILL, D.S. 1975: Agricultural insect pests of the tropics and their

control. – Cambridge University Press, London, 516 pp.

HILL, D.S. 2008: Pests of crops in warmer climates and their con-

trol. – Springer, Berlin, 708 pp.

HÔGMO, O. 2003: Some new or interesting ants species from

Gran Canaria, Canary Islands (Hymenoptera: Formicidae). –

Vieraea 31: 197-200.

HÖLLDOBLER, B. & WILSON, E.O. 1990: The Ants. – Harvard

University Press, Cambridge, MA, 732 pp.

HORVITZ, C.C. & SCHEMSKE, D.W. 1986: Seed dispersal of a

neotropical myrmecochore: variation in removal rates and dis-

persal distance. – Biotropica 18: 319-323.

HUNG, A.C.F. & VINSON, S.B. 1977: Interspecific hybridization and

caste specificity of protein in fire ant. – Science 196: 1458-1460.

IHERING, H. VON 1894: Die Ameisen von Rio Grande do Sul. –

Berliner Entomologische Zeitschrift 39: 321-446.

JEANNE, R.L. 1979: A latitudinal gradient in rates of ant preda-

tion. – Ecology 60: 1211-1224.

JERDON, T.C. 1851: A catalogue of the species of ants found in

Southern India. – Madras Journal of Literature & Science 17:

103-127.

JOUVENAZ, D.P., ALLEN, G.E., BANKS, W.A. & WOJCIK, D.P.

1977: A survey for pathogens of fire ants, Solenopsis spp., in the

Southeastern United States. – Florida Entomologist 60: 275-279.

KEMPF, W.W. 1961: A survey of the ants of the soil fauna in

Surinam (Hymenoptera: Formicidae). – Studia Entomologica

4: 481-524.

KEMPF, W.W. & BROWN, W.L. 1968: Report on some Neotropi-

cal ant studies. – Papeis Avulsos do Departamento de Zoolo-

gia 22: 89-102.

KIRITANI, K. & MORIMOTO, N. 2004: Invasive insect and nema-

tode pests from North America. – Global Environmental Re-

search 8: 75-88.

KORZUKHIN, M.D., PORTER, S.D., THOMPSON, L.C. & WILEY, S.

2001: Modelling temperature-dependent range limits for the

ﬁre ant Solenopsis invicta (Hymenoptera: Formicidae) in the

United States. – Environmental Entomology 30: 645-655.

KROLL, J.C., ARNOLD, K.A. & GOTIE, R.F. 1973: An observation

of predation by native fire ants on nestling Barn Swallows. –

Wilson Bulletin 85: 478-479.

LONGINO, J.T. 2005: Solenopsis geminata (FABRICIUS 1804). –

<http://academic.evergreen.edu/projects/ants/genera/solenopsis

/species/geminata/geminata.html>, retrieved on 10 January 2010.

LUND, P.W. 1831: Lettre sur les habitudes de quelques fourmis

du Brésil, adressée a M. Audouin. – Annales des Sciences Na-

turelles 23: 113-138.

MAES, J.M. & MACKAY, W.P. 1993: Catálogo de las hormigas

(Hymenoptera: Formicidae) de Nicaragua. – Revista Nicaragu-

ense de Entomología 23: 1-46.

MANN, W.M. 1916: The ants of Brazil. – Bulletin of the Museum

of Comparative Zoology 60: 399-490.

MANN, W.M. 1922: Ants from Honduras and Guatemala. – Pro-

ceedings of the United States National Museum 61: 1-54.

MAYR, G. 1861: Die europäischen Formiciden. – C. Gerolds Sohn,

Vienna, 80 pp.

MAYR, G. 1862: Myrmecologische Studien. – Verhandlungen der

Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft

in Wien 12: 649-776.

MAYR, G. 1865: Formicidae. – Reise der Österreichischen Fre-

gatte "Novara" um die Erde in den Jahren 1857, 1858, 1859.

Zoologischer Theil. 2(1): 1-119.

MAYR, G. 1876: Die australischen Ameisen. – Journal des Muse-

ums Godeffroy Hamburg 12: 56-115.

MAYR, G. 1886: Die Formiciden der Vereinigten Staaten von

Nordamerika. – Verhandlungen der Kaiserlich-Königlichen

Zoologisch-Botanischen Gesellschaft in Wien 36: 419-464.

MAYR, G. 1897: Formiciden aus Ceylon und Singapur. – Terme-

szetrajzi Fuzetek 20: 420-436.

MCINNES, D.A. & TSCHINKEL, W.R. 1996: Mermithid nematode

parasitism of Solenopsis ants (Hymenoptera: Formicidae) of

Northern Florida. – Annals of the Entomological Society of

America 89: 231-237.

MENOZZI, C. 1942: Formiche dell'isola Fernando Poo e del terri-

torio del Rio Muni (Guinea Spagnola). 24. Beitrag zu den wis-

senschaftlichen Ergebnissen der Forschungsreise H. Eidmann

nach Spanisch-Guinea 1939 bis 1940. – Zoologischer Anzeiger

140: 164-182.

MENOZZI, C. & RUSSO, G. 1930: Contributo alla conoscenza della

mirmecofauna della Repubblica Dominicana (Antille). – Bol-

lettino del Laboratorio di Zoologia Generale e Agraria della

Reale Scuola Superiore d'Agricoltura, Portici 24: 148-173.

MORLEY, B.D.W. 1953: The ant world. – Penguin Books, London,

190 pp.

MORRISON, L.W. 1997: Polynesian ant (Hymenoptera: Formicidae)

species richness and distribution: a regional survey. – Acta

Oecologica 18: 685-695.

MORRISON, L.W., PORTER, S.D., DANIELS, E. & KORZUKHIN, M.D.

2004: Potential global range expansion of the invasive fire ant,

Solenopsis invicta. – Biological Invasions 6: 183-191.

MOUTIA, L.A. & MAMET, R. 1946: A review of twenty-five years

of economic entomology in the island of Mauritius. – Bulletin

of Entomological Research 36: 439-472.

MRAZEK, R.W. 1974: The relationship of the fire ant (Solonopsis

geninata [sic] FAB) to nestlings of birds nesting on two spoil

islands in the Laguna Madre. – Texas Journal of Science 25:

140.

NASCIMENTO, R.P. DO 2005: Conservação de invertebrados em

áreas urbanas: um estudo de caso com formigas no Cerrado

Brasileiro. – Dissertação de Mestrado, Ecoligia e Conservação

de Recursos Naturais, Universidade Federal do Uberlândia,

Uberlândia, Brazil, 64 pp.

NEVILLE, P.J., O'DOWD, D.J. & YEN, A.L. 2008: Issues and implica-

tions for research on disturbed oceanic islands illustrated through

an ant survey of the Cocos (Keeling) Islands. – Journal of Insect

Conservation 12: 313-323.

O'KEEFE, S.T., COOK, J.L., DUDEK, T., WUNNEBURGER, D.F.,

GUZMAN, M.D., COULSON, R.N. & VINSON, S.B. 2000: The dis-

tribution of Texas ants. – Southwestern Entomologist Supple-

ment 22: 1-92.

ORDELHEIDE, C.H. 1929: Een nieuwe bestrijdingswijze van de

roode tabaksmier (Solenopsis geminata) op zaadbedden (sum-

mary). – Review of Applied Entomology 18: 59.

PARDO VARGAS, R. 1964: Clave para identificar los Formicidae

de la Provincia de Chiclayo. – Revista de Peruana Entomologia

7: 98-102.

PERGANDE, T. 1893: On a collection of Formicidae from Lower

California and Sonora, Mexico. – Proceedings of the Califor-

nia Academy of Sciences (2)4: 26-36.

PITTS, J.P. 2002: A cladistic analysis of the Solenopsis saevissima

species-group (Hymenoptera: Formicidae). – Ph.D. disserta-

tion, University of Georgia, Athens, GA, 266 pp.

PLOWES, R.M., LEBRUN, E.G., BROWN, B.V. & GILBERT, L.E.

2009: A review of Pseudacteon (Diptera: Phoridae) that para-

sitize ants of the Solenopsis geminata complex (Hymenoptera:

Formicidae). – Annals of the Entomological Society of Ame-

rica 102: 937-958.

PORTER, S.D. 1992: Frequency and distribution of polygyne fire

ants (Hymenoptera: Formicidae) in Florida. – Florida Ento-

mologist 75: 248-257.

PRINS, A.J., ROBERTSON, H.G. & PRINS, A. 1990: Pest ants in

urban and agricultural areas of southern Africa. In: VANDER

MEER, R.K., JAFFE, K. & CEDENO, A. (Eds.): Applied myrme-

cology: a world perspective. – Westview Press, Boulder, CO,

pp. 25-33.

RADOSZKOWSKY, O. 1884: Fourmis de Cayenne Française. –

Trudy Russkago Entomologicheskago Obshchestva 18: 30-39.

RISCH, S.J. & CARROLL, C.R. 1986: Effects of seed predation by

a tropical ant on competition among weeds. – Ecology 67:

1319-1327.

ROGER, J. 1862: Synonymische Bemerkungen. – Berliner Ento-

mologische Zeitschrift 6: 283-297.

ROGER, J. 1863: Verzeichnis der Formiciden-Gattungen und Ar-

ten. – Berliner Entomologische Zeitschrift 7 (Suppl.): 1-65.

ROTHNEY, G.A.J. 1889: Notes on Indian ants. – Transactions of

the Entomological Society of London 1889: 347-374.

SANTANA-REIS, V.P.G. & SANTOS, G.M. DE M. 2001: Influência da

estrutura do habitat em comunidades de formigas (Hymeno-

ptera - Formicidae), Feira de Santana, Bahia, Brasil. – Sitien-

tibus Ciéncias Biológicas 1(1): 66-70.

SANTOS, G.M. DE M., DELABIE, J.H.C. & RESENDE, J.J. 1999:

Caracterizacao da mirmecofauna (Hymenoptera – Formicidae)

associada a vegetacao periferica de inselbergs (caatinga arbo-

rea estacional semi decidua) em Itatim - Bahia - Brasil. – Siti-

entibus, Feira de Santana 20: 33-43.

SANTSCHI, F. 1909: Formicides nouveaux ou peu connus du

Congo Français. – Annales de la Société Entomologique de

France 78: 349-400.

SANTSCHI, F. 1913: Glanures de fournis Africaines. – Annales

de la Société Entomologique de Belgique 57: 302-314.

SANTSCHI, F. 1914: Formicides de l'Afrique occidentale & aus-

trale du voyage de Mr. le Professeur F. Silvestri. – Bollettino

del Laboratorio di Zoologia Generale e Agraria della Reale

Scuola Superiore d'Agricoltura, Portici 8: 309-385.

SANTSCHI, F. 1915: Nouvelles fourmis d'Afrique. – Annales de

la Société Entomologique de France 84: 244-282.

SANTSCHI, F. 1920: Fourmis d'Indo-Chine. – Annales de la So-

ciété Entomologique de Belgique 60: 158-176.

SANTSCHI, F. 1923: Solenopsis & autres fourmis néotropicales.

– Revue Suisse de Zoologie 30: 245-273.

SANTSCHI, F. 1939: Résultats scientifiques des croisières du Navire-

École Belge "Mercator" vol. 2. XIV. Formicidae. – Memoires du

Musee Royale d'Histoire Naturelle de Belgique (2)15: 159-167.

SIVAPRAGASAM, A. & CHUA, T.H. 1997: Natural enemies for the

cabbage webworm, Hellula undalis (FABR.) (Lepidoptera: Py-

ralidae) in Malaysia. – Researches on Population Ecology 39:

3-10.

SMITH, F. 1858: Catalogue of hymenopterous insects in the col-

lection of the British Museum. Part VI. Formicidae. – British

Museum, London, 216 pp.

SMITH, F. 1859: Catalogue of hymenopterous insects collected by

Mr. A. R. Wallace at the Islands of Aru and Key. – Journal

and Proceedings of the Linnean Society of London, Zoology

3: 132-178.

SMITH, F. 1862: Descriptions of new species of aculeate Hyme-

noptera, collected at Panama by R. W. Stretch, Esq, with a list

of described species, and the various localities where they

have previously occurred. – Transactions of the Entomolo-

gical Society of London (3)1: 29-44.

SMITH, M.R. 1930: A list of Florida ants. – Florida Entomolo-

gist 14: 1-6.

SMITH, M.R. 1951: Formicidae. In: MUESEBECK, C.F.W., KROM-

BEIN, K.V. & TOWNES, H.K. (Eds.): Hymenoptera of America

north of Mexico. Synoptic Catalog. – United States Depart-

ment of Agriculture Monograph 2: 778-875.

SMITH, M.R. 1965: House-infesting ants of the eastern United

States. – United States Department of Agriculture Technical

Bulletin 1326: 1-105.

SMITH, M.R. 1979: Superfamily Formicoidea. In: KROMBEIN, K.

V., HURD, P.D. Jr., SMITH, D.R. & BURKS, B.D. (Eds.): Cata-

log of Hymenoptera in America north of Mexico. Volume 2.

Apocrita (Aculeata). – Smithsonian Institution Press, Wash-

ington DC, pp. 1323-1467.

SNELLING, R.R. & HUNT, J.H. 1975: The ants of Chile (Hymeno-

ptera: Formicidae). – Revista Chilena de Entomologia 9: 63-129.

STAHL, C.F. & SCARAMUZZA, L.C. 1929: Soil insects attacking

sugar cane in Cuba. – Tropical Plant Research Foundation

Bulletin 10: 1-19.

STARR, F., STARR, K. & LOOPE, L.L. 2007: Survey for little fire

ant (Wasmannia auropunctata) on the island of Maui, Ha-

waii. Hawaiian Ecosystems at Risk project (HEAR). – Puune-

ne, Hawaii, 35 pp.

STODDARD, H.L. 1931: The bobwhite quail. – Charles Scribner's

Sons, New York, 559 pp.

SUTHERST, R.W. & MAYWALD, G. 2005: A climate model of the

red imported fire ant, Solenopsis invicta BUREN (Hymenoptera:

Formicidae): implications for invasion of new regions, particu-

larly Oceania. – Environmental Entomology 34: 317-335.

TABER, S.W. 2000: Fire ants. – Texas A&M University Press,

College Station, TX, 308 pp.

TAYLOR, B. 2007: Ants of Africa. Ninth edition. – <http://antbase.

org/ants/africa>, retrieved on 20 November 2007.

TINSLEY, J.D. 1898: An ants'-nest coccid from New Mexico. –

Canadian Entomologist 30: 47-48.

TOBIN, J.E. 1995: Ecology and diversity of tropical forest canopy

ants. In: LOWMAN, M.D. & NADKARNI, N.M. (Eds.): Forest can-

opies. – Academic Press, San Diego, CA, pp. 129-147.

TRAGER, J.C. 1991: A revision of the fire ants, Solenopsis gemi-

nata group (Hymenoptera: Formicidae: Myrmicinae). – Jour-

nal of the New York Entomological Society 99: 141-198.

TRAVIS, B.V. 1938: Fire ant problem in the Southeast with spec-

ial reference to quail. – Transactions of the North American

Wildlife Conference 3: 705-708.

TRAVIS, B.V. 1941: Notes on the biology of the fire ant Sole-

nopsis geminata (F.) in Florida and Georgia. – Florida Ento-

mologist 24: 15-22.

TSCHINKEL, W.R. 1988: Distribution of the fire ants Solenopsis

invicta and S. geminata (Hymenoptera: Formicidae) in north-

ern Florida in relation to habitat and disturbance. – Annals of

the Entomological Society of America 81: 76-81.

TSCHINKEL, W.R. 2006: The fire ants. – Belknap Press, Cam-

bridge, MA, 723 pp.

URICH, F.W. 1915: Insects affecting the sugar-cane in Trinidad.

– Bulletin, Department of Agriculture Trinidad and Tobago

16(5): 156-161.

VARNHAM, K. 2006: Non-native species in UK Overseas Terri-

tories: a review. – Joint Nature Conservation Committee Re-

port 372: 1-35.

WARREN, L.O. & ROUSE, E.P. 1969: The ants of Arkansas. – Uni-

versity of Arkansas Agriculture Experiment Station Bulletin

742: 1-68.

WASMANN, E. 1890: Neue myrmekophile Staphyliniden aus Bra-

silien. – Deutsche Entomologische Zeitschrift 1890: 305-318.

WASMANN, E. 1896: Die Ameisen- und Termitengäste von Brasi-

lien. I. Theil. Mit einem Anhange von Dr. August Forel. – Ver-

handlungen der Kaiserlich-Königlichen Zoologisch-Botanischen

Gesellschaft in Wien 45: 137-179.

WATERHOUSE, D.F. 1997: The major invertebrate pests and weeds

of agriculture and plantation forestry in the southern and west-

ern Pacific. – Australian Centre for International Agricultural

Research, Canberra, ACT, 93 pp.

WEBER, N.A. 1948: Studies on the fauna of Curaçao, Aruba, Bon-

aire and the Venezuelan islands: 14. Ants from the Leeward

group and some other Caribbean localities. – Natuurweten-

schappelijke Studiekring voor Suriname en Curacao 5: 78-86.

WETTERER, J. 2006: The tropical fire ant, Solenopsis geminata, on

an important sea turtle nesting beach in Tortuguero National

Park, Costa Rica. Proceedings of the 23rd Annual Symposium

on Sea Turtle Biology and Conservation. – National Oceanic

and Atmospheric Administration Technical Memorandum, Na-

tional Marine Fisheries Service - Southeast Fisheries Science

Center 536: 281-283.

WETTERER, J.K. 2008: Worldwide spread of the longhorn crazy

ant, Paratrechina longicornis (Hymenoptera: Formicidae). –

Myrmecological News 11: 137-149.

WETTERER, J.K. 2009: Worldwide spread of the ghost ant, Tapi-

noma melanocephalum (Hymenoptera: Formicidae). – Myr-

mecological News 12: 23-33.

WETTERER, J. K. & DAVIS, L.R. Jr. 2010: The red imported fire

ant, Solenopsis invicta, (Hymenoptera: Formicidae) in the Les-

ser Antilles. – Florida Entomologist 93: 138-139.

WETTERER, J.K. & O'HARA, B.C. 2002: Ants of the Dry Tortugas,

the outermost Florida Keys. – Florida Entomologist 85: 303-307.

WHEELER, W.M. 1901: Notices biologiques sur les fourmis mex-

icaines. – Annales de la Société Entomologique de Belgique

45: 199-205.

WHEELER, W.M. 1902: A consideration of S. B. Buckley's "North

American Formicidae." – Transactions of the Texas Academy

of Science 4: 17-31.

WHEELER, W.M. 1905: The ants of the Bahamas, with a list of

the known West Indian species. – Bulletin of the American

Museum of Natural History 21: 79-135.

WHEELER, W.M. 1907: A collection of ants from British Hon-

duras. – Bulletin of the American Museum of Natural History

23: 271-277.

WHEELER, W.M. 1908: The ants of Texas, New Mexico and Ari-

zona (Part 1). – Bulletin of the American Museum of Natural

History 24: 399-485.

WHEELER, W.M. 1910: Ants: their structure, development and

behavior. – Columbia University Press, New York, 663 pp.

WHEELER, W.M. 1913: Ants collected in the West Indies. – Bul-

letin of the American Museum of Natural History 32: 239-244.

WHEELER, W.M. 1914: Ants and bees as carriers of pathogenic

micro-organisms. – American Journal of Tropical Diseases

and Preventive Medicine 2: 160-168.

WHEELER, W.M. 1915: Some additions to the North American

ant fauna. – Bulletin of the American Museum of Natural His-

tory 34: 389-421.

WHEELER, W.M. 1919a: The ants of Tobago Island. – Psyche

26: 113.

WHEELER, W.M. 1919b: The ants of Borneo. – Bulletin of the Mu-

seum of Comparative Zoology of Harvard College 63: 43-147.

WHEELER, W.M. 1919c: Expedition of the California Academy

of Sciences to the Galapagos Islands, 1905-1906. XIV. The

ants of the Galapagos Islands. – Proceedings of the Califor-

nia Academy of Sciences (4)2(2): 259-297.

WHEELER, W.M. 1922: The ants collected by the American Mu-

seum Congo Expedition. – Bulletin of the American Museum

of Natural History 45: 39-269.

WHEELER, W.M. 1923: Report on the ants collected by the Barba-

dos-Antigua Expedition from the University of Iowa in 1918.

– Studies in Natural History, Iowa University 10: 3-9.

WHEELER, W.M. 1926: The natural history of ants. From an un-

published manuscript in the archives of the Academy of Sci-

ences of Paris by René Antoine Ferchault de Réaumur. Trans-

lated and annotated by William Morton Wheeler. – A. Knopf,

New York, 280 pp.

WHEELER, W.M. 1927a: A few ants from China and Formosa. –

American Museum Novitates 259: 1-4.

WHEELER, W.M. 1927b: Ants collected by Professor F. Silvestri

in Indochina. – Bollettino del Laboratorio di Zoologia Gene-

rale e Agraria della Reale Scuola Superiore d'Agricoltura, Por-

tici 20: 83-106.

WHEELER, W.M. 1928: Ants collected by Professor F. Silvestri

in China. – Bollettino del Laboratorio di Zoologia Generale e

Agraria della Reale Scuola Superiore d'Agricoltura, Portici 22:

3-38.

WHEELER, W.M. 1935: Check list of the ants of Oceania. – Occa-

sional Papers of the Bernice Pauhahi Bishop Museum 11(11):

1-56.

WHEELER, W.M. 1936: Ants from the Society, Austral, Tuamo-

tu and Mangareva Islands. – Occasional Papers Bernice P.

Bishop Museum 12(18): 3-17.

WILSON, E.O. 2005: Early ant plagues in the New World. –

Nature 433: 32.

WILSON, E.O. & TAYLOR, R.W. 1967: Ants of Polynesia. – Paci-

fic Insects Monograph 14: 1-109.

WITHERS, W.A. 1898: Horticultural experiments at Southern Pines,

1896. – The North Carolina Agricultural Experiment Station

Bulletin 159: 93-174.

WOJCIK, D.P., ALLEN, C.R., BRENNER, R.J., FORYS, E.A., JOU-

VENAZ, D.P. & LUTZ, R.S. 2001: Red imported fire ants: im-

pact on biodiversity. – American Entomologist 47: 16-23.

WOJCIK, D.P., BUREN, W.F., GRISSELL, E.E. & CARLYSLE, T. 1976:

The fire ants (Solenopsis) of Florida (Hymenoptera: Formici-

dae). – Florida Department of Agriculture & Consumer Ser-

vices, Division of Plant Industry, Entomology Circular 173: 1-4.

WYCKHUYS, K.A.G. & O'NEIL, R.J. 2007: Influence of extra-

field characteristics to abundance of key natural enemies of

Spodoptera frugiperda SMITH (Lepidoptera: Noctuidae) in

subsistence maize production. – International Journal of Pest

Management 53: 89-99.

ZHANG, R., LI, Y., LIU, N. & PORTER, S.D. 2007: An overview

of the red imported fire ant (Hymenoptera: Formicidae) in

mainland China. – Florida Entomologist 90: 723-731.

GABI-I: The global ant biodiversity informatics-island database

Article

Dec 2022

Island systems are known to harbor disproportionate amounts of geographically restricted biodiversity, but also for experiencing high rates of species loss, ultimately representing critical systems with significant conservation values. Knowledge of the biodiversity value of insular systems remains, however, highly fragmented and incomplete for many groups of organisms, especially insects. This gap limits our understanding of their global significance for biodiversity and inhibits prioritization for future exploration and conservation efforts. Here, we developed a new database introducing current knowledge of ants on 2678 islands globally, based on nominal species, and providing information on their native or exotic status. In total, this database contains 7,010 ant species (44.6% of the known global ant fauna) that have been recorded on islands globally from 449,232 records. In addition, this database identifies 108 large islands (area > 200km2) that have received no ant sampling efforts globally. This new data set provides the most comprehensive understanding of ant diversity and composition on islands globally, opening new opportunities to address questions on a multitude of research questions and fields related to biogeography, ecology, and evolution. This data set also provides a roadmap for future exploration and conservation actions of ants on islands as well as for overall ant diversity, with updates available as new records and taxonomic updates are published. There are no copyright restrictions on this database and users should cite this data paper in publications when using the data. This article is protected by copyright. All rights reserved.

Novel alkaloids from the fire ant, Solenopsis geminata

Article

Full-text available

Feb 2022

South American fire ants, Solenopsis richteri and Solenopsis invicta , were accidently introduced into the southern USA in the 1900s and 1930s, respectively. The rapid spread and high population densities of S. invicta , and its potent sting, resulted in broad economic impacts and a variety of research efforts. In the 1970s, their venom alkaloids were identified as a complex blend of trans -2-methyl-6-alkyl- and alkenyl-piperidines. Solenopsis geminata is a worldwide tramp species but a native of the southern coastal regions of the USA. It was found to only produce cis - and trans -2-methyl-6-undecyl-piperidines. These alkaloids were considered the Solenopsis ancestral alkaloid profile since they were identified from female sexuals (potential queens) of all Solenopsis species in South and North America. The dramatic modification of alkaloids in Solenopsis invicta was attributed to their response to evolutionary pressure and the lack of change in S. geminata alkaloids due to no response to evolutionary pressure. Here we report the unexpected discovery of 6-undecyl-pyridine, 2-methyl-6-undecyl-pyridine and 2-methyl-6-(1)-undecenyl-pyridine as components of S. geminata worker venom, suggesting that S. geminata like its South American relatives have responded to evolutionary pressures. Our results will stimulate future research on S. geminata populations throughout the tropical/subtropical world.

Phylogenomic Delimitation of Morphologically Cryptic Species in Globetrotting Nylanderia (Hymenoptera: Formicidae) Species Complexes

Article

Full-text available

Jan 2022

The ant genus Nylanderia Emery has a cosmopolitan distribution and includes 150 extant described species and subspecies, with potentially hundreds more undescribed. Global taxonomic revision has long been stalled by strong intra- and interspecific morphological variation, limited numbers of diagnostic characters, and dependence on infrequently collected male specimens for species description and identification. Taxonomy is further complicated by Nylanderia being one of the most frequently intercepted ant genera at ports of entry worldwide, and at least 15 globetrotting species have widespread and expanding ranges, making species-level diagnoses difficult. Three species complexes (‘bourbonica complex’, ‘fulva complex’, and ‘guatemalensis complex’) include globetrotting species. To elucidate the phylogenetic positions of these three complexes and delimit species boundaries within each, we used target enrichment of ultraconserved elements (UCEs) from 165 specimens representing 98 Nylanderia morphospecies worldwide. We also phased the UCEs, effectively doubling sample size and increasing population-level sampling. After recovering strong support for the monophyly of each complex, we extracted COI barcodes and SNPs from the UCE data and tested within-complex morphospecies hypotheses using three molecular delimitation methods (SODA, bPTP, and STACEY). This comparison revealed that most methods tended to over-split taxa, but results from STACEY were most consistent with our morphospecies hypotheses. Using these results, we recommend species boundaries that are conservative and most congruent across all methods. This work emphasizes the importance of integrative taxonomy for invasive species management, as globetrotting occurs independently across at least nine different lineages across Nylanderia.

Diversity and distribution of epigeic ants across elevation gradients and between habitat types of Mogale’s Gate

Thesis

Full-text available

Jan 2023

Johan Saayman

Ants are important ecosystem engineers and invasive ants pose serious threats to biodiversity of southern Africa. Biogeography databases are important for studying biodiversity, understanding invasion ecology and in conservation management. This study aimed to create a biogeographical database of epigeic ants within the Mogale's Gate located in Gauteng, South Africa. A species inventory of epigeic ants was created, the distributions of invasive species were identified, and the stability and homogeneity of ant communities where asses by calculating Shannon Diversity Index and Shannon Equitability Index scores. Ants were sampled using pitfall trapping along a 200 m elevation gradient and in grassland, wetland and woodland habitats in Mogale’s Gate from July to September 2022. A total of 60 species were identified, six of which were invasive. The highest species diversity was recorded at mid and high elevations and the lowest diversity was recorded in wetlands. Invasive species were present in all samples, with Pheidole megacephala and Lepisiota capensis being the most abundant. The Shannon Diversity Index scores indicated that the epigeic ant assemblage of Mogale’s Gate is partially degraded, with woodlands having degraded ant assemblages. Low Shannon Equitability Index scores for all sampled sites, especially wetlands and woodlands, indicated high species homogeneity in communities. An ant monitoring programme would greatly benefit ant ecology research and biodiversity management at Mogale’s Gate.

Impact of Solenopsis geminata pest (Hymenoptera: Formicidae), the tropical fire ant on soybean (Glycine max) production in Littoral, Cameroon

Article

Full-text available

Nov 2022

In Ndog-bong and Mboppi, soybean was planted at three replication on three different plots: one of these plots was non-infested, while the other two were infested with 124 190 and 186 285 workers of Solenopsis geminata respectively. Comparison was done between the infested plots and the non-infested one on seed germination, plant density, nodule number and yield. The data collected showed that, the four studied parameters decreased with the increasing of Solenopsis geminata foragers in the infested plots. The germinating rate of soybean seeds was 48.82%, 28.77% and 22.41% in the non-infested, slightly infested and heavily infested plots respectively. Plant density was 40.04%, 33.07% and 26.89% in the non-infested, slightly infested and heavily infested plots respectively. Nodule number was 38.36%, 32.63% and 29.01% in the non-infested, slightly infested and heavily infested plots respectively. Yield was 1.36t/ha, 0.82t/ha and 0.60t/ha in the non-infested, slightly infested and heavily infested plots respectively. In conclusion, direct feeding of Solenopsis geminata on seeds, seedlings and plant root reduced plant density and caused an important reduction of soybean yield.

Comparison of recruitment and competition behavior between Solenopsis geminata and tow resident ant species in Cameroon

Article

Full-text available

Jan 2022

In Cameroon, we compared recruitment and competition behavior between Solenopsis geminata and two resident ant species i.e. Paratrechina longicornis and Pheidole megacephala. For the recruitment essays, a 35 cm long and 30 cm wide plywood were placed in contact with three nest and fried fish was deposited at 15 cm from the nest. The mean number of Solenopsis geminata foragers collected on the fish was compared with that of the two resident ants. On the other hand, individual and group aggression assays were used to competition evaluation between Solenopsis geminata and the two resident ants. In individual aggression essays, one medium-sized of Solenopsis geminata worker and one medium-sized worker of each resident ant species were separately placed in a Petri dish. Aggression between the two competitor ants was recorded and a comparison was done between ant species on the attacks initiation by the competitors. In the group essay, 150 workers of each resident ant species were separately allowed to competition with 150 workers of Solenopsis geminata and a comparison was done between the two groups of competitors on the mean number of ant species found on the baits and the mean mortality. Our result showed that the mean number of Pheidole megacephala recruited on the fish (156.47±16.05) was the highest, follow by Paratrechina longicornis (140.53±9.21) and Solenopsis geminata (127.54±8.54). During individual aggression essays, Solenopsis geminata workers initiated more attacks (67.33%) than those of Paratrechina longicornis (32.67%), while Pheidole megacephala workers initiated more attacks (62.38%) than those of Solenopsis geminata (37.62%). In the group essay for the species pair, the mean number of Solenopis geminata workers on the bait (30.30±0.60) was higher than that of Paratrechina longicornis (12.16±1.10), while the mean number of Pheidole megacephala workers on the bait (22.50±1.50) was higher than that of Solenopsis geminata (18.60±2.00). Moreover, the mean mortality of Paratrechina longicornis (61.94±0.48) was higher than that of Solenopsis geminata (38.06±0.48), while the mean mortality of Solenopsis geminata (58.64±1.25) was higher than that of Pheidole megacephala (41.36±1.25). The data led us to conclude that Pheidole megacephala is more competitive than Solenopsis geminata and can then be used to his control.

Genome-wide SNPs reveal the social structure and invasion pathways of the invasive tropical fire ant (Solenopsis geminata)

Preprint

Full-text available

Jul 2022

Elucidating invasion pathways of invasive species is often challenging because invasive populations frequently have low genetic diversity caused by genetic bottlenecks during introduction events. Genome-wide sequencing such as Restriction Site-Associated DNA Sequencing (RADseq) can overcome these challenges by generating thousands of genome-wide single nucleotide polymorphic (SNP) markers. The tropical fire ant, Solenopsis geminata, is a global invader with low genetic diversity in its introduced range, making RADseq one of the best available methods to investigate its population genetics. We used double digest RADseq to generate 3,834 SNPs to compare the genetic diversity of S. geminata in its introduced range to its most likely source of introduction, determined the invasion pathways among populations at an unprecedented level of detail for this species, and determined the social structure of S. geminata workers collected in 13 locations worldwide. We found that introduced S. geminata went through a strong genetic bottleneck. We also identified multiple secondary introduction events among S. geminata populations, indicating that the bridgehead effect is an important driver in the global spread of this species. We found that all colonies in the introduced range were polygyne (i.e., with more than one queen) which may increase their invasion success and potential to cause adverse effects.

Clove and its constituents against urban pests: Examples from ants and cockroaches

Chapter

Full-text available

Jan 2022

Urban pests are organisms that constantly interfere with human interests and transmit diseases causing microorganisms. Among urban pests, ants and cockroaches are categorized under household and public health insect pests. Urban pests live near or sometimes live in human habitats; therefore, pest control strategies should be susceptible. To control urban pests, environmental, human, and nontargeted animal-friendly control methods are always in high demand instead of synthetic toxic chemicals. Botanicals are better alternatives to the conventional synthetic toxic pesticides against urban pests. Clove (Syzygium aromaticum) has been used in several forms, such as clove oil derived from dried clove flower bud, eugenol, eugenyl acetate, and β-caryophyllene that are major oil constituents, and clove bud powder. Essential oils from clove, clove powder, or its constituents have repellent, toxic, and anesthetic properties against many urban pest insects. In this chapter, significant studies yet on ants and cockroaches control applying different forms of clove are reported.

Remarkable diversity in a little red dot: a comprehensive checklist of known ant species in Singapore (Hymenoptera: Formicidae) with notes on ecology and taxonomy

Article

Full-text available

Jul 2022

Despite a legacy of extensive deforestation, the 720 km2 city state of Singapore still harbours impressively diverse flora and fauna. Given increasing evidence of global insect declines, we urgently need to better document and protect local insect diversity. Numerous species of ants (Hymenoptera, Formicidae) have been recorded or described from Singapore since its founding in 1819. However, it has been over a century since Hugo Viehmeyer (1916) documented a total of 159 species found in the country. Here, we present an updated comprehensive checklist of all named species and subspecies of ants found in Singapore, with specimen collection data, and notes on taxonomy and ecology in the local context. We compiled the list based on museum collections material (the Zoological Reference Collection), primary literature sources, and verified records from known overseas repositories. We documented a total of 409 nominal species and subspecies, also a few notable morphospecies, from 10 subfamilies and 100 genera. These include new records for 121 species and 10 genera. Another 96 species and subspecies have types designated from Singapore; of these, 34 are currently considered as endemic. We also raised nine subspecies to species and synonymized two species, providing reasons justifying each status change: 1) Camponotus (Tanaemyrmex) carinifer stat. n., 2) Camponotus (Tanaemyrmex) tinctus nom rev., 3) Paraparatrechina malaccana stat. n., 4) Aphaenogaster simulans Forel, 1915 stat. n., 5) Myrmicaria adpressipilosa stat. n., 6) Vollenhovia minuta stat. n., 7) Vollenhovia brevicornis (Emery, 1893) = V. fridae Forel, 1913 syn. n., 8) Hypoponera javana stat. n., 9) Hypoponera singaporensis stat. n., 10) Mesoponera javana stat. n. Most species are considered native to Indomalaya, including 13 cosmopolitan tramps. Only 10 other species are presumed exotic to the region. At the time of writing, Singapore can be deemed the city with the highest recorded ant diversity in the world. Despite the sheer numbers, this list remains incomplete, with more species awaiting discovery or taxonomic resolution in future. The immense diversity of ants in Singapore is mainly threatened by continued decimation of remnant forest habitats and encroaching urban developments.

Exotic Ants of the Asia-Pacific: Invasion, National Response, and Ongoing Needs

Article

Jan 2022

Human activity has facilitated the introduction of many exotic species via global trade. Asia-Pacific countries comprise one of the most economically and trade-active regions in the world, which makes it one of the most vulnerable regions to invasive species, including ants. There are currently over 60 exotic ant species in the Asia-Pacific, with the red imported fire ant, Solenopsis invicta, among the most destructive. Exotic ants pose many economic and ecological problems for the region. Countries in the Asia-Pacific have dealt with the problem of exotic ants in very different ways, and there has been an overall lack of preparedness. To improve the management of risks associated with invasive ants, we recommend that countries take action across the biosecurity spectrum, spanning prevention, containment, and quarantine. The creation of an Asia-Pacific network for management of invasive ants should help prevent their introduction and mitigate their impacts. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Resource partitioning among epigaeic and hypogaeic ants (Hymenoptera: Formicidae) of a Brazilian cocoa plantation

Article

Full-text available

Jan 1995

Patterns of dietary and foraging strata utilization by the ground ant community of a Brazilian cocoa planatation were examined using sugar, meat and flour baits on the surface as well as buried. A total of 49 ant species was recorded, including 10 species of Pheidole. Strong dominance was exercised by Solenopsis geminata at both surface and subterranean strata, and at all food resources. The dissimilarity matrix of the epigaeic ant fauna was much greater than that for the hypogaeic species. At least four guilds were identified: the fungus-growing ants, epigaeic nectivores, epigaeic carnivores, and hypogaeic foragers. Niche breadth reduction, leading to the formation of guilds, permits the coexistence of many species in the this ground ant community from a tropical cocoa plantation. -Authors

Red Imported Fire Ants: Impact on Biodiversity

Article

Full-text available