Ants: Formica sp.

 Ants: Formica sp. (Pallidefulva group)
Order Hymenoptera – Ants, Bees, Wasps and Sawflies
Live adult ants and eggs photographed at Allegheny National Forest, Pennsylvania.
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Allegheny Mound Ant

Ants are distinguished from other insects by the combination of elbowed antennae, a strongly constricted second abdominal segment forming a distinct node-like petiole, a wingless worker caste, and the presence of a metapleural gland. They can sense with organs located on the antennae, which can detect pheromones (single compounds) and hydrocarbons on the outer layer of the body (a set of different compounds). The latter is highly important for the recognition of nestmates from non-nestmates. Also, they communicate with sound in the form of vibrations moving through the ground.

They live in colonies with well-defined castes that typically comprise a worker caste of sterile females and a reproductive caste of winged males and females. (Most queens and male ants (drones) have wings, which they eat after their nuptial flight.

Ants tending aphid farm
Ant tending aphid farm
Trophobiotic ants and aphids
Ants "milk" aphids for their sugar-laden secretion: honeydew

Definitions: Myrmecology is the branch of entomology dealing with ants.
Myrmecochorous (adj.) dispersed by ants.
Myrmecophagous (adj.) feeding on ants.
Myrmecophile (n.) an organism that habitually shares an ant nest myrmecophilous adj., myrmecophily n.

Allegheny mound ant
Allegheny mound ant (Formica exsectoides) herding treehopper and nymphs
  • Antbase — The complete catalogue of all ants of the world linked to all available full text systematics publications (>4,000), links, pictures, etc.
  • AntWeb — Images of more than 4,000 specimens including all ant genera
  • Myrmecos.net — An extensive image gallery of ants in the wild.
  • h2g2 article on Ants 

    • Order Hymenoptera: Bees, Wasps, & Ants

    Hymenoptera (Latin for membrane wing) is a vast assemblage of insects second only to Coleoptera (beetles) in the number of described species. Hymenoptera number some 115,000 species – 18,000 of them call North America home. Hymenopterans inhabit a wide variety of habitats, and show an incredible diversity in size, behavior, structure and color.
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