''Myrmeconema neotropicum'' is a tetradonematid

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

parasite. It appears to induce fruit mimicry in the tropical ant. Presently the only known host species is ''

Cephalotes atratus ''Cephalotes'' is a genus (biology), genus of arboreal, tree-dwelling ant species from the Americas, commonly known as turtle ants. All appear to be gliding ants, with the ability to "parachute" and steer their fall so as to land back on the tre ...

'', a

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

ant Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...

with a black

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

. Upon

infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

, the gaster, or bulbous hindmost region of the

, resembles one of the many red berries found in tropical forest canopies.

Life cycle

''Myrmeconema neotropicum's'' life cycle begins when a bird eats the infected ant. Upon passing through the bird's digestive system the eggs are defecated out. The eggs are then picked up by the ants and fed to their larvae. Once inside the immature ant gut the eggs migrate to the gaster where they will fully mature. Once the ant larvae pupate the mature nematodes begin to reproduce inside of the gaster. The males expire soon after mating but the females hold the eggs within themselves. Once the ant develops into a young adult the gaster begins to become translucent, thus allowing the red embryos to be seen. The longer the ant is parasitized the redder the gaster becomes. The infected ant then travels outside now mimicking small red berries which are a favorite food of frugivorous birds. The ant is confused for a berry and is eaten by the bird starting the whole cycle over again. Although bird predation on an infected ''Cephalotes atratus'' has not yet been observed, the combination of field experiments and the known natural history of the ant indicate that this is the most

parsimonious In philosophy, Occam's razor (also spelled Ockham's razor or Ocham's razor; ) is the problem-solving principle that recommends searching for explanations constructed with the smallest possible set of elements. It is also known as the principle o ...

explanation for transmission of the parasite to new ant colonies.

Signs and symptoms

Infected ants develop bright red gasters, tend to be more sluggish, and walk with their gasters in a conspicuous elevated position. According to Shik et al. (2011), infected gasters had 57% more mass, but 37% lower metabolic rates, compared to uninfected gasters. These changes likely cause

frugivorous A frugivore ( ) is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance ...

birds to mistake the infected ants for berries and eat them. Increased reddening coincides with a shift in ant behavior that includes foraging outside the nest, thus increasing the probability of consumption by a duped bird.

Morphology

Female ''Myrmeconema neotropicum'' mature within the gaster of the host ants. They are about 1 mm in length and about 112 μm at their greatest width. Males are smaller than females (680 μm in length and 97 μm in diameter) (Poinar & Yanoviak 2008). The infected young adult ant is completely black and spends most of its time tending brood within the nest. As the parasite embryos develop within the eggs, the ant gaster becomes translucent, ultimately appearing bright red.

References

* * *Yanoviak, S. P., M. Kaspari, R. Dudley, G. Poinar Jr. 2008. Parasite-induced fruit mimicry in a tropical canopy ant. The American Naturalist 171:4, 536–544. *Jonathan Z. Shik, Michael Kaspari, and Stephen P. Yanoviak (''2011''). Preliminary Assessment of Metabolic Costs of the Nematode Myrmeconema neotropicum on its Host, the Tropical Ant Cephalotes atratus. Journal of Parasitology: October 2011, Vol. 97, No. 5, pp. 958–959. *Evans, C. (2015, February 5). Parasitic Mind Control. Retrieved from http://www.sciencenutshell.com/parasitic-mind-controlmyrmeconema-neotropicum/ {{Taxonbar, from=Q1953495 Enoplea Parasitic nematodes of animals Parasites of Hymenoptera