Pyramica membranifera

  • Synopsis
  • Diagnostic Characters
  • Comparison Chart
  • Images
  • Video
  • Nomenclature
  • References & Links

Threat Level: Low

Pyramica membranifera is a minute, relatively uncommon species. The distinct appearance of P. membranifera is characterized by a triangular head, six-segmented antennae with a two-segmented antennal club, antennal scrobes, triangular mandibles, spongiform appendages on the propodeum and waist, and spatulate hairs on the antennal scapes. Like all myrmicines, P. membranifera also has a two-segmented waist and a gaster armed with a sting.

Strumigenys is closely related to Pyramica, and both are genera within the tribe Dacetini. The most reliable character for separating P. membranifera from the two species of Strumigenys included in PIAkey is the shape of the mandibles. The mandibles of P. membranifera are triangular, and those of the Strumigenys are linear.

Wilson and Taylor (1967) offer the following discussion of P. membranifera.

Brown (1949) states that T. membranifera [the species was referred to as Trichoscapa membranifera prior to the taxonomic revision of Bolton (2000)] is probably of African origin. It has been spread by human commerce through a large part of the tropics and warm temperate zones, including such diverse areas as the Fiji Is., eastern China, West Indies and southeastern United States. The species has an ecological amplitude unusual for a dacetine, nesting in major habitats from dense woodland to dry, open cultivated fields. Wilson (1953) describes the feeding behavior of the workers; they are predaceous on a wide variety of small, soft-bodied arthropods.

The tribe Dacetini is very diverse, and its species can be difficult to identify because of their minute size and subtle morphological differences. There are many native species and introduced species of dacetines in the Pacific. If the species included in PIAkey do not match the specimen in question, explore images on Antweb or use the keys published by Wilson and Taylor (1967) or Bolton (2000) for identification confirmation.

  • Waist with two segments (petiole & postpetiole)
  • Propodeal spines present, but hidden by spongiform material
  • Antennal club with two segments

  • Antenna with a total of six segments
  • Head shape triangular
  • Mandibles triangular
Pyramica membranifera vs. Strumigenys species

P. membranifera S. rogeri S. godeffroyi
Head
Profile
Head shape

triangular

triangular

triangular
Mandible shape

triangular

linear

linear
Number of preapical teeth on mandible (not applicable)
two

one
Head with ventral notch (not applicable)
present

absent
Hairs on dorsum of petiole, postpetiole & gaster (not applicable)
spatulate
(shaped like a spatula)

flagellate
(long, thin & tapering)
P. membranifera S. rogeri S. godeffroyi

Pyramica membranifera
CASENT0171134
(head, worker)

Pyramica membranifera
CASENT0171134
(profile, worker)

Pyramica membranifera
CASENT0171134
(dorsal, worker)

Pyramica membranifera
CASENT0171134
(label, worker)

No video is available for this species.

Subfamily Myrmicinae

Pyramica membranifera. Strumigenys (Trichoscapa) membranifera Emery, 1869b: 24, fig. 11 (w.) ITALY. Emery, 1916b: 205 (q.); Wheeler, G.C. & Wheeler, J. 1991b: 93 (l.). Combination in S. (Cephaloxys): Emery, 1916b: 205; in Trichoscapa: Brown, 1948e: 113; in Pyramica: Bolton, 1999: 1673. Senior synonym of foochowensis, marioni, santschii, silvestriana, simillima, vitiensis, williamsi: Brown, 1948e: 114. See also: Brown, 1949d: 6; Wilson, 1954: 483; Bolton, 1983: 319; Bolton, 2000: 322.

  • Antweb: specimen images, data & maps
  • Bolton, B. (2000) The ant tribe Dacetini. Memoirs of the American Entomological Institute, 65, 492-1028.

  • Wilson, E.O. & Taylor, R.W. (1967) The ants of Polynesia (Hymenoptera: Formicidae). Pacific Insects Monograph, 14, 1-109. [referred to as Trichoscapa membranifera]