Dorymyrmex flavopectus

An attractive species of the highly drained, infertile rosemary scrub and open sand pine woodlands of peninsular Florida.

Identification
Trager (1988) - Head, except near base of mandibles, and gaster uniform dark brown; thorax clear orange-yellow; slenderer and with somewhat longer legs and scapes than Dorymyrmex bureni: colonies polycalic, interconnected by trails.

D. flavopectus workers from the Ocala National Forest are notably larger than those from Highlands Co., where the types were collected. Northern specimens have HTL 1.90-2.25 mm, while Highlands Co. specimens have HTL 1.70-.2.00. Specimens from the 2 localities are alike in all other respects.

Distribution
Dorymyrmex flavopectus is restricted to stands of Florida rosemary, Ceratiola ericoides Michaux, including those in early stages of succession to sand pine woodland in the sterile, highly drained, white "sugar sands" of central Florida.

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Mexico.

Biology
Trager (1988) - The only other Dorymyrmex likely to be encountered in the habitat occupied by D. flavopectus is Dorymyrmex bossutus, though of course Dorymyrmex bureni is found along roads through such areas. D. flavopectus is spottily distributed, and though much apparently suitable habitat is not occupied, where found it is conspicuous by its polycalic colonies; the several nests occupied by each colony are interconnected in clement conditions by well-travelled trails of the strikingly colored workers. Nests are difficult to excavate in the fine, crumbly sand, but are apparently shallow and many-branched. Queens have never been taken.

Nomenclature

 *  flavopectus. Dorymyrmex pyramicus subsp. flavopectus Smith, M.R. 1944d: 15 (w.) U.S.A. Combination in Conomyrma: Kusnezov, 1952g: 430; in Dorymyrmex: Shattuck, 1992c: 85. Raised to species: Kusnezov, 1952g: 430. See also: Snelling, R.R. 1973b: 4; Buren, Nickerson & Thompson, 1976: 306; Trager, 1988: 22; Johnson, C. 1989b: 192 (in key).

Trager (1988):

Worker
HL 0.78-1.00, HW 0.63-0.90, SL 0.88-1.14, EL 0.18-0.24, FL 0.80-1.03, WL 1.00-1.43, HTL 1. 78-2.43, CI 80.8-90.0, SI 126.4-142.0, OI 21.2-24.5, FI 96.4-106.3, TI 128.2-143.0. N =26. (Holotype not measured)

General form and characters as in figures and in key.

Head broadest at or slightly below midpoint of eye, converging more strongly toward mandibles; occipital border straight to weakly convex; promesonotal curvature as in Fig. 11, generally less arched than that of D. bureni, though variable in both species; propodeal cone a little higher and sharper than in D. bureni and apparently deflected to rear in most specimens.

Mandibular striae as in Dorymyrmex bureni; tessellation of body surface of larger "mesh" than that of D. bureni, so D. flavopectus shinier overall, in spite of having longer, more conspicuous pubescence on head and gaster.

Color pattern unique; mandibles, clypeus, and thorax, especially the latter, clear uninfuscated orange-yellow, or rarely there is faint infuscation near lower lateral edges of pronotum; underside and coxae dark brown, at some viewing angles showing through edges of nota giving illusion of infuscation; head and gaster piceous brown; gaster appears grayer because of long whitish pubescence; legs dark brown. Among sympatric species, only Dorymyrmex bossutus may approximate this color pattern, but is smaller, shinier and with thorax browner than D. flavopectus.

Type Material
Five paratypes: Archbold Biological Station, Lake Placid. Florida. Aug. 24 1943. #35. T. C. Schnierla. (at U. S. National Museum).

Smith (1944) lists a holotype and 12 paratypes as the material upon which he based his description. Only 5 specimens from the type series are now found at the U. S. National Museum, none of them labeled as a holotype. I have not chosen a lectotype, since the holotype may be rediscovered. These specimens have slightly different collection data than those listed in Smith's description.

Etymology
D. flavopectus derives from Latin flavus (yellow) plus pectus (chest) referring to the striking yellow thorax of workers of this species. The name is a noun in apposition, and is not modified to agree in gender with Dorymyrmex.

References based on Global Ant Biodiversity Informatics

 * Alatorre-Bracamontes, C.E. and M Vasquez-Bolanos. 2010. Lista comentada de las hormigas (Hymenoptera: Formicidae) del norte de México. Dugesiana 17(1):9-36
 * Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
 * Deyrup M., C. Johnson, G. C. Wheeler, J. Wheeler. 1989. A preliminary list of the ants of Florida. Florida Entomologist 72: 91-101
 * Deyrup, M. 2003. An updated list of Florida ants (Hymenoptera: Formicidae). Florida Entomologist 86(1):43-48.
 * Deyrup, M. and J. Trager. 1986. Ants of the Archbold Biological Station, Highlands County, Florida (Hymenoptera: Formicidae). Florida Entomologist 69(1):206-228
 * Jeanne R. J. 1979. A latitudinal gradient in rates of ant predation. Ecology 60(6): 1211-1224.
 * Johnson C. 1986. A north Florida ant fauna (Hymenoptera: Formicidae). Insecta Mundi 1: 243-246
 * Trager J. C. 1988. A revision of Conomyrma (Hymenoptera: Formicidae) from the southeastern United States, especially Florida, with keys to the species. Florida Entomologist 71: 11-29
 * Van Pelt A. F. 1958. The ecology of the ants of the Welaka Reserve, Florida (Hymenoptera: Formicidae). Part II. Annotated list. American Midland Naturalist 59: 1-57
 * Van Pelt A. F. 1966. Activity and density of old-field ants of the Savannah River Plant, South Carolina. Journal of the Elisha Mitchell Scientific Society 82: 35-43.
 * Van Pelt A., and J. B. Gentry. 1985. The ants (Hymenoptera: Formicidae) of the Savannah River Plant, South Carolina. Dept. Energy, Savannah River Ecology Lab., Aiken, SC., Report SRO-NERP-14, 56 p.
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133