DISTRIBUTION-Formica fossaceps

Pinawa, Rennie, Sandilands Provincial Forest
(Wheeler et al., 1989)


Key characteristics to the species of Formica rufa Group of Manitoba (Jeff Shaddock (unpublished) and adapted from Wheeler and Wheeler (1963))

1. Crest of petiole much thinner; in profile the anterior face slopes rearward to the crest even when the latter is blunt; gastric pubescence usually appressed and never reflected
2. Scapes usually without erect hairs, but if erect hairs are present then body hairs are not of uniform length
3. Petiolar scale seen from behind with the crest convex or angularly produced upward in the middle, the sides of the scale tapering inward from crest to peduncle
4. Clypeal fossae deep and pit like, the anterior edge of the clypeus, which bounds them in front, sweeping upward in an even curve to the median lobe; clypeus box-like
5. Middle and hind tibiae without erect hairs except for a double row on flexor surface
6. Erect hairs absent from upper surface of body; gaster with extremely fine short scattered pubescence, its surface strongly shining

  • Photo Credit:Shannon Hartman © AntWeb 2002 - 2013
  • Photo Credit:Shannon Hartman © AntWeb 2002 - 2013

  • Taxonomic Classification

          Phylum: Arthropoda
          Subphylum: Hexapoda
               Class: Insecta
               Subclass: Pterygota
               Infraclass: Neoptera
                     Order: Hymenoptera
                     Suborder: Apocrita
                     Infraorder: Aculeata
                              Superfamily: Vespoidea
                              Family: Formicidae
                              Subfamily: Formicinae
                              Tribe: Formicini
                                 Genus: Formica
                                 Species: Formica fossaceps

    Specific Biology

    Originally described by Buren as from a wooded pasture, all published and unpublished records since have been from treeless, native, bluestem grassland.
    Natural History:
    F. fossaceps is a tallgrass prairie species, perhaps endemic to the glaciated tallgrass region. It is a mound builder that often uses grass blades as a primary thatching material, sometimes yielding the appearance of a small haystack. Where I have observed it in Harrison Co. Missouri, it occurs mostly in wetter portions of the prairie protected at TNC Dunn Ranch Preserve and the nearby Pawnee Prairie Conservation Area, among a much larger population of F. montana, and I have a similar observation from a small remnant of wet prairie near Waverly, Iowa. Trails of the shiny, bicolored workers of F. fossaceps often travel among several thatched mounds, which have a clumped distribution on the prairie. Workers also occur in numbers at thriving membracid colonies on sunflowers, ironweeds and other prairie plants, and also on flowers of invasive Pastinaca sativa. Queens are microgynous, and this species is most likely a temporary parasite of F. montana, as well as possibly autoparasitic and budding within mound clusters.

    Source: Ant Web