Solenopsis Geminata, The Tropical Fireant

Solenopsis Geminata, a medium size red ant is one of the most common ant found throughout Malaysia especially in areas where there are human activities. Polymorphism in this species of fireant is high with several typical sizes of workers - at least six.

Unlike Solenopsis invicta, the invasive pest species from South America, Solenopsis geminata is strictly a ground dwelling ant, they also don't do well in heavily wooded areas. Few nest are found in such areas. Aside from the obvious morphological expression in the worker class where Solenopsis geminata is definitive by its mega super major worker with a disproportionately large head, there have also been no recorded instances of S. geminata also building bivouac floating nest raft in flooding conditions.

However in nest founding and growth S. geminata share the strategic behavior of colony boosting when newly founded nest would on encountering another newly founded nest amalgamate together in favor of the larger. In some instances the queens of the smaller nests would be immediately driven off or killed (if she did not leave) by the resident queen while in other instances she may be tolerated up to a certain period. One possible trigger for the resident (or dominant) queen to attack other amalgamated queens could be food limitation. Also possibly because of this strategic behavior of nest/colony boosting, in S. geminata their matured colonies are very nest scent sensitive such that workers separated from the nest for a few days when they are returned are treated as alien and attack by their nest mates.

Also typical with many species of ants during the early stages of the nest the queen would serve as a sort of semi replete for the nest gorging on food. This usually stop once the nest has sufficiently developed in size and the queen becomes the dedicated egg producing 'machine' and nest mother.

Aside from a fairly painful sting which is deployed by this species both as a defense as well as to kill prey, Solenopsis geminata with their gaster raised also squeezed out a drop of formic acid as a defensive posture and deterrent to fend of other ants around their food find, around their nest site and along their foraging trails.

The smallest worker with the largest major worker. The large head to body ratio of this largest worker makes it a lumbering clumsy ant.

A male alate. Large thorax region makes this a powerful flyer. Solenopsis geminata mating takes place in mid flight. They will not mate on the ground.

Female alates.

The nuptial flights takes place around sunset usually after a day or previous day of rain.

A brooding new queen of Solenopsis geminata.

The founding gyne of Solenopsis geminata attending to her first clutch of eggs.

A new gyne with her first batch of eggs. The Solenopsis geminata queen is a prolific egg layer.

The egg clutch after a few days.

Workers hatch and begins foraging within a month. Nest matures around 6 months producing the first batch of alates. Despite being monogynous Solenopsis geminata nest are large typically numbering around six thousand individuals. Large nest may number over ten thousand workers.

The queen in new nest serving as a food replete.

Workers hatch and begins foraging within a month. Nest matures around 6 months producing the first batch of alates. Despite being monogynous Solenopsis geminata nest are large, typically numbering around six thousand individuals. Large nest may number over ten thousand workers.

A typical colony would normally number around a thousand workers before they would begin to produce the largest of the worker morphological form. This usually takes between two to three months from the colony founding. By restricting food to a founding colony, (above and below) is a nest that have been kept to a minimum size of between thirty to fifty workers and manipulated to produce the largest major worker. This is done by restricting food until into the third month and then feeding the colony with an abundant supply of protein rich food. Supplying an abundant food to the colony from the beginning when the workers start foraging however does not induce the production of this super majors until the third month by which time the colony would have reach between two thousand to five thousand workers (which is too large to manage in a small container).

One drawback to this interference manipulation of the colony development is that the full expression of the workers morphology from the smallest minor through to the largest major was not realized. So instead of the full workers morphological expression of six sizes we see only two (sometimes three).

A newly eclosed super major worker. This largest worker of the Solenopsis geminata may vary slightly in size.

The Mutation (Genetic Abbreviation)?

In Solenopsis geminata there is a fairly common occurrence where in the founding brood there are these 'mutant' larvae. These larvae are fairly mobile with actively moving heads similar to those of Ponerinae ants. They grow to quite large in the founding stage resulting in very few successful workers eclosing. But there is never a successful pupation of these mutant larvae, they typically puncture leaking out their fluids or die when once they reached a certain size. Below a founding queen with such a larva.

Taxonomy  

No rank: cellular organisms 131567
Superkingdom (Domain): Eukaryota 2759
No rank: Opisthokonta 33154
Kingdom: Metazoa 33208
No rank: Eumetazoa 6072
No rank (Subkingdom): Bilateria 33213
No rank (Branch): Protostomia 33317
No rank (Infrakingdom): Ecdysozoa
No rank (Superphylum): Panarthropoda 88770
Phylum: Arthropoda 6656
No rank (Subphylum): Mandibulata 197563
No rank: Pancrustacea 197562
Subphylum (Epiclass): Hexapoda 6960
Class: Insecta 50557
No rank (Subclass): Dicondylia 85512
Subclass (Infraclass): Pterygota 7496
Infraclass: Neoptera 33340
Cohort: Holometabola
Order: Hymenoptera 7399
Suborder Apocrita 7400
Infraorder: Aculeata 7434
Superfamily: Formicoidea
Family: Formicidae 36668
Subfamily: Myrmicinae 34695

Tribe: Solenopsidini 144017

Genus: Solenopsis 13685

Species: geminata 121131


Last Updated; 2021 07 22
First Posted: 2012 09 16
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