Formica biophilica

A species that escaped notice as a distinctive form until a recent revision of the pallidefulva group by Trager et al. in 2007.

Identification
A member of the Formica pallidefulva group.

Trager et al. (2007) - F. biophilica and Formica incerta are sympatric in the southern part of the latter’s range. In the field, F. biophilica appears more brightly and uniformly reddish-yellow in color, and (if several workers of a colony are present) weakly polymorphic, whereas F. incerta is more brownish yellow, smaller overall, and usually (though not invariably) more monomorphic within colonies. Metrically, F. biophilica is more slender, has a proportionally longer mesosoma and narrower head than F. incerta (compare SI, TWI and CI values). F. biophilica usually has more macrochaetae on the propodeum than on the pronotum (20 of 32 specimens), whereas F. incerta normally has macrochaetae on the pronotum in excess of those on the propodeum (22 of 30 specimens).

F. biophilica is also somewhat more brightly and uniformly colored, more shiny and overall less hairy, and has a sharper petiolar crest in profile than Formica dolosa. The F. biophilica specimens examined in this study also had a significantly higher CTI and OI (had more elongate form and relatively larger eyes) than F. dolosa. In the South, the less pilose minor workers and nanitics of F. biophilica can be difficult to differentiate from Formica pallidefulva. Often a rather squarer propodeal profile and more uniform bright reddish yellow color indicate F. biophilica. Additionally, on average the TWI of F. pallidefulva is larger than that of F. biophilica. Ecologically, specimens from fens, bogs, swamps and fresh or salt marshes are most likely to be F. biophilica. In the northern part of the range of F. biophilica, its bright color will always distinguish it from the at least partially brown F. incerta and F. pallidefulva.

Key to US Formica pallidefulva group species

Distribution
Trager et al. (2007) - Found in mesic to hydric open habitats, including lawns, fields, prairies, fens, bogs, marshes and open woodlands, from the Carolinas to Missouri, south to northern Florida and central Texas. Northward, its occurrence is more sporadic in formerly glaciated regions, where Formica biophilica shifts to drier (thus warmer) loess and sandy grassland locations. It reaches central Illinois in the prairie region and southeastern New York along the East Coast. The habitat overlaps that of Formica incerta in unglaciated prairies and eastern meadows, and overlaps that of Formica dolosa in southern pine woodland and savanna. F. biophilica is apparently absent from the most severely xeric and infertile sites occupied by F. dolosa. In the Ozarks and other southern hills, F. biophilica occurs in groundwater fens, bogs, marshes and flatwoods. This is the only southern Formica that occurs in these wetland habitats, where during periods of high water table, it nests in the elevated hummocks of organic matter formed by grass or sedge tussocks. It is less common than Formica pallidefulva in human habitats, but occasionally shows up in lawns, parks and campuses, especially in parts of the South where fire ants are less abundant.

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

Biology
Trager et al. (2007) - Nests of F. biophilica have simple, cryptic openings in wetlands, grasslands or less often, in open woodlands. The entrance is usually hidden amongst grass. In springtime, colonies of F. biophilica may build a 10-25 cm diameter mound of soil and plant fragments nestled against a grass or sedge clump, this collapsing in disuse during the hot, dry weather of summer. In fens, bogs and wet meadows, when ground at the base is permanently or seasonally saturated, F. biophilica nests in the upper parts of grass or sedge tussocks. One colony under a strip of bark in unmowed grass in eastern Missouri contained four larvae of myrmecophilous staphylinid beetles, probably Xenodusa cava LeConte, (but not collected for determination).

This species has been found as host to the slavemaker Polyergus lucidus s. l. in Washington, D.C., northern Georgia and east-central Missouri. The variety of this slavemaker parasitizing F. biophilica has longer scapes and is somewhat less shiny and slightly more pubescent than typical P. lucidus lucidus Mayr, which parasitizes Formica incerta. F. biophilica occurs among the many hosts of Formica pergandei in the prairies of Missouri, but has only been observed in combination with other host species. At one site, a F. pergandei nest contained a mélange of six slave species including (in order of decreasing relative abundance) Formica pallidefulva, Formica subsericea Say, F. biophilica, Formica dolosa, F. incerta and Formica obscuriventris Mayr, certainly the most species-rich, naturally occurring ant colony on record!

Sexuals have been collected in nests in Missouri, Texas and Georgia in mid-June to early July, but no flight or colony-founding activity has been recorded. There is one example of a queen-male bilateral gynandromorph in a Missouri collection. The worker pupae are always enclosed in a pale tan cocoon, and the sexuals in a larger, darker cocoon.

Nomenclature

 *  biophilica. Formica biophilica Trager, J.C., in Trager, MacGown & Trager, 2007: 617, figs. 4b, 5b, 6b (w.q.m.) U.S.A.

Worker
Trager et al. (2007) - Holotype HL 1.43 mm; HW 1.15; EL 0.42; SL 1.70; WL 2.34; PW 0.95; PnM 6; PpM 14; TM 30

Gracile, shiny, and the brightest yellow member of the group. Head, mesosoma and legs light reddish- to pale brownish yellow; head and mesosoma not at all or only a little lighter than gaster. Dorsal sclerites of mesosoma and especially the gaster with long, usually curved, erect macrochaetae. Number of macrochaetae on propodeum usually exceeds the number on the pronotum (20 of 32 specimens examined). Sheen of gaster readily visible through pubescence composed of pale, slender, grayish hairs of medium density. Erect macrochaetae on gaster long, commonly 0.25-0.30 mm, tapering to a point and curved (Figure 4b).

Queen
Trager et al. (2007) - Color, gastral pubescence and shininess like the workers’, with the usual differences in size; with faint tessellation of upper portion of head, pronotum, sides of mesothorax, propodeum and gastral dorsum; wings, when present, clear to light brownish.

Male
Trager et al. (2007) - Pubescence and pilosity abundant; mesosomal dorsum dull-punctate; head and gaster very dark brown, appearing black; mesosoma dusky yellowish brown, legs reddish brown; wings clear to light brownish. A little brighter in color, especially mesosoma, less pilose, pilosity also finer, and less pubescent than Formica dolosa.

Type Material
Type specimen label: ALABAMA, Chilton Co., Interstate-65 rest area 3 mi. E of Thorsby. 1-X-1983. M.B., J.R., B.R. DuBois. Holotype and three paratypes on two pins. The holotype and one paratype will be deposited at the at Harvard, and the other two specimens will be added to the excellent material of this species collected in Alabama and elsewhere by W. S. Creighton, now housed at the.

Etymology
The name biophilica is given in allusion to E. O. Wilson’s popularly inspirational coining “biophilia”, meaning the love of other species as a part of human nature. Specimens from Alabama, Dr. Wilson’s home state, were chosen as the type series to further honor his contributions to myrmecology, conservation and behavioral biology.