Introduction

Stigmatomma Roger, 1859 belongs to the subfamily Amblyoponinae, an ancient and morphologically distinctive lineage of ants characterized by elongate linear mandibles, a dentate clypeal margin, a nodiform petiole bearing a conspicuous anteroventral lamella, and a functional sting. Members of the genus are specialized predators, hunting primarily geophilomorph centipedes and other soft-bodied arthropods in the soil and leaf litter. More than 130 species are recognized globally (Bolton 2025), distributed across tropical and warm-temperate regions worldwide.

The genus Stigmatomma is found in tropical and temperate regions of the world. In the Nearctic region, they usually occur in wooded areas. Members of this genus are found in soil and leaf litter throughout the United States, except in the north central region. Currently, three species are recognized in the U.S., but only two have been found in the Southeast,Stigmatomma pallipes (Haldeman), a widespread species distributed throughout much of the United States, and S. trigonignatha Brown, known only from North Carolina.

Taxonomic History
Stigmatomma pallipes (Haldeman, 1844) valid

• Ponera pallipes Haldeman, 1844: 54 (w.) U.S.A. (Pennsylvania).
• Primary type material: Holotype worker; depository: Academy of Natural Sciences of Philadelphia (presumed).
• Combination in Stigmatomma: Roger, 1859: 246.
• Combination in Amblyopone: Mayr, 1861: 47; Wheeler, 1904: 299; Creighton, 1950: 44; Smith, 1951: 785; Smith, 1967: 344; Kempf, 1972: 14; Smith, 1979: 1328.
• Status as species: Haldeman, 1844: 54; Roger, 1863: 16; Mayr, 1886: 420; Wheeler, 1904: 299; Wheeler, 1910: 137; Creighton, 1950: 44; Bolton, 1995: 62; MacGown & Forster, 2005: 62; Bolton, 2025.
• Senior synonym of Amblyopone pallipes var. tennesseensis Wheeler, 1904: Creighton, 1950: 44; Bolton, 1995: 62.

Common Name
Dracula ant; pale-footed Amblyopone ant

Diagnosis
Stigmatomma pallipes can be distinguished from other North American Stigmatomma by the following combination of characters: worker head subquadrate, approximately as long as broad; anterior clypeal margin armed with 6–7 stout conical median teeth (appearing as 9–10 when lateral tubercles are fully divided); mandibles elongate and linear, with 4–5 paired teeth along the convex median portion, a large triangular basal tooth, a small subapical tooth, and a robust apical tooth; mesosoma strongly constricted at the mesonotum and anterior propodeum in dorsal view; propodeal dorsum meeting the declivity at a sharply defined angle; petiolar node with a large rounded anteroventral lamella; dorsal head surface and pronotal flanks densely punctate, giving a coriaceous, opaque appearance; constriction between abdominal segments III and IV well developed. Coloration reddish brown to dark brown; appendages slightly paler.

Stigmatomma pallipes can be distinguished from S. trigonignathum by the presence of a tooth on each side of the head near the point of mandibular insertion and by the mandible being slender for its entire length, rather than having the basal portion enlarged and triangular in shape, as in S. trigonignathum.

Identification
Descriptions for each caste are based on examination of MEM specimens and published literature (Wheeler 1904; Creighton 1950).

Worker. TL: 4.11–5.59 mm; HL: 0.95–1.28 mm; HW: 0.84–1.21 mm; SL: 0.46–0.65 mm; ML: 1.36–1.86 mm; EL: 0.02–0.05 mm. (n = 5, MEM specimen).

Head in full-face view subquadrate, approximately as long as broad; sides weakly narrowed anteriorly near mandibular insertions and more distinctly narrowed posteriorly; posterolateral corners forming well-defined occipital angles; posterior margin flat in full-face view. Frontal lobes large, prominent, only weakly divergent posteriorly, enclosing a subcircular frontal area. Anterior clypeal margin straight to weakly convex, armed medially with 6–7 stout conical teeth; lateral clypeal tubercles large, and when fully divided the margin presents 9–10 subequal teeth. Mandibles elongate and linear, masticatory margins sinuate; each armed with 4–5 paired teeth along the convex median portion, a large triangular basal tooth, a small subapical tooth, and a powerful apical tooth; mandibles crossing at rest. Compound eyes small, usually composed of 8–10 poorly defined ommatidia, occasionally with as many as 20. Antennal scapes stout; when laid back, surpassing the midpoint between antennal insertion and occipital angle by approximately the maximum width of the scape. Funicular segments 2–5 longer than broad in large workers, occasionally slightly broader than long in small workers; segments 6–10 gradually increasing in width; terminal segment approximately as long as the two preceding segments combined.

Mesosoma in dorsal view strongly constricted at the mesonotum and anterior propodeum. Pronotum oval in outline, posterior margin concave at the promesonotal suture. Mesonotum short, strap-like, usually less curved anteriorly than the adjacent pronotal margin, occasionally bowed anteriorly and appearing weakly chevron-shaped. Propodeum subtrapezoidal in dorsal view, sides diverging posteriorly from the impressed metanotal groove to the flat declivitous face. In lateral view, anterior half of pronotum convex; posterior half of pronotum, mesonotum, and propodeal dorsum nearly flat; mesonotum typically slightly elevated above adjacent dorsal surfaces. Propodeal dorsum distinctly longer than the declivity, meeting it at a sharp, well-defined angle; declivity steep to nearly vertical.

Petiolar node in dorsal view subcircular, slightly broader than long in large workers; narrower and slightly longer than broad in small workers, posterior margin truncate. In lateral view, petiole with short anterior peduncle leading abruptly into a steep anterior face; dorsal and posterior faces forming a continuous, weakly convex surface meeting the anterior face at a distinct angle. Ventral surface bearing a large rounded lamella projecting conspicuously anteroventrally. Gaster elongate-oval; constriction between abdominal segments III and IV well developed. Sting long and robust.

Mandibles and clypeus longitudinally striate, weakly shining. Dorsal surface of head and lateral surfaces of pronotum densely punctate, punctures close-set and producing a coriaceous, opaque appearance in most lights. Genae, gula, mesosoma dorsum, and dorsal surface of petiolar node more sparsely punctate and correspondingly more shining. Lower mesopleura and metapleura longitudinally striate. Propodeal declivity typically opaque with fine transverse striation, though striation weakened and surface more shining in some specimens. Lateral surfaces of petiolar node and abdominal segments III and IV with small scattered punctures on an otherwise strongly shining, finely shagreened background. Remaining gastral segments strongly shining, finely shagreened; punctures mostly restricted to the posterior margins bearing erect setae.

Pilosity abundant. Erect setae fine, short, and numerous over most of the body surface, becoming longer and stouter on the posterior gastral segments. Many setae suberect, grading into pubescence on the head, mesosoma, petiole, and anterior gastral segments. Antennal scapes, funiculi, tibiae, and tarsi densely clothed with short erect setae; femora with fewer setae. Mandibles with relatively few setae, these longer and stouter than most cephalic setae. Clypeus typically bearing 2–3 very long erect setae. Posterior margins of gastral segments bearing numerous long stout erect setae.

Body reddish brown to dark brown; head and mesosoma typically darker than petiole and gaster; appendages slightly paler, yellowish brown to pale brown.

Queen. TL: 5.55–6.11 mm; HL: 1.21–1.30 mm; HW: 1.12–1.21 mm; SL: 0.61–0.65 mm; ML: 1.86–2.12 mm; EL: 0.14–0.20 mm. (n = 5, MEM specimen).

Similar to worker in mandibular and cephalic structure, sculpture, and pilosity, but larger with a markedly more massive mesosoma bearing a fully developed flight sclerite complex. Eyes well developed, composed of approximately 100 ommatidia; anterior margin positioned near the midlength of head (excluding mandibles). Three ocelli present, well developed. Antennal scape, when laid back, nearly reaching the level of the lateral ocelli. Mesoscutum and mesoscutellum convex in lateral profile. Wings hyaline with pale yellow venation; pterostigma brown. Petiole nodiform with prominent anteroventral lamella as in worker; gaster with well-developed postpetiolar constriction and exserted sting. Color yellowish brown to reddish brown; mesosoma often darker.

Male. TL: 4.32–5.33 mm; HL: 0.76–0.85 mm; HW: 0.85–1.02 mm; SL: 0.11–0.15 mm; ML: 1.61–1.95 mm; EL: 0.40–0.50 mm. (n = 5, MEM specimen).

Body smaller and more gracile than queen; coloration dark brown to black; appendages somewhat paler. Head in full-face view rounded to subglobose, wider than long; compound eyes large and convex; ocelli conspicuous. Mandibles elongate, narrow, and curved as in worker and queen but proportionally more slender; inner margins toothed. Antennae long and filiform; scapes short; funiculi elongate. Mesosoma compact, strongly sculptured, dark. Wings hyaline with pale venation. Petiole low and nodiform. Gaster elongate. Sculpture of head and mesosoma dense, producing a matte to finely coriaceous surface. Pilosity short and appressed to suberect; longer setae at gastral apex.

Biology and Economic Importance
Habitat: Although only one or two specimens are usually collected at any given time, this species does not seem to be uncommon in the Southeast. It is typically found in mesic and dry-mesic woodlands and forests, but has been collected in prairies, and other habitats throughout the southeastern United States. We have even collected this species in arid inland sand dunes at the Ohoopee Dunes Natural Area in Emanuel County, Georgia. This species usually nests in rich, slightly moist, soil beneath rotting logs or stones, in leaf litter at tree bases, or in decomposing logs and stumps. Colonies are relatively small. Although this species can be visually detected in the field, its dark coloration makes it somewhat difficult to find. Most specimens tend to be collected in soil or litter samples.

Natural History: The main source of food of this species is reported to be chilopods (Smith, D. R., 1979). Foragers hunt singly for geophilomorph centipedes, which they grasp with long, bidenticulate-toothed mandibles and paralyze with a long and powerful sting. Prey may be dragged into a nearby nest or larvae may be brought to the paralyzed prey to feed (Trager pers. comm). Members of this genus are sometimes referred to as Dracula ants because queens of some species obtain much of their nutrients from hemolymph of their larvae. The queen, and sometimes workers, puncture the integument of the larvae, which results in a small drop of hemolymph, which is then lapped up. For more about this bizarre behavior, see Alex Wild's online article about the related species Stigmatomma oregonensis (link). Although I rarely encounter more than a few workers at a time, I have seen numerous alates, both male and female, in malaise and Lindgren funnel traps, which gives me the impression that this species is quite common. We routinely collect this ant in wooded areas, and in a current study of Mississippi ants, have already collected it in over one-fourth of the counties in the state. Alates have been collected in mid July.

This species would not typically be considered a pest species and generally would have little or no obvious impact on mankind. However, this species does have the capabililty of stinging, and it is concievable that alate females could get caught in someones clothing and sting them. This sort of thing is know to happen with various ponerine ants, although I do not know of any instances of this species stinging anybody.

Distribution
Ont., Que., south to FL, west to WI, IA, OK, CO, TX, AZ (Smith, D. R., 1979); found in all of the southeastern states including AL, AR, FL, GA, LA, MO, MS, NC, SC, TN. More broadly, the species has been recorded from the following states: Alabama, Arkansas, Arizona, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Vermont, Virginia, West Virginia, and Wisconsin, as well as Ontario and Quebec, Canada (Creighton 1950; Smith 1979; Bolton 2025).

Literature Cited
Bolton, B. 1995. A new general catalogue of the ants of the world. Cambridge, Mass.: Harvard University Press, 504 pp.

Bolton, B. 2025. An online catalog of the ants of the world. Available from https://antcat.org. (accessed 2 June 2026).

Creighton, W. S. 1950. The ants of North America. Bulletin of the Museum of Comparative Zoology 104:1–585.

Haldeman, S. S. 1844. Descriptions of some new species of insects in the collection of the Academy of Natural Sciences, &c. Proceedings of the Academy of Natural Sciences of Philadelphia 2:53–54.

Kempf, W. W. 1972. Catálogo abreviado das formigas da região Neotropical. Studia Entomologica 15:3–344.

MacGown, J. A.; Forster, J. A. 2005. A preliminary list of the ants (Hymenoptera: Formicidae) of Alabama, U.S.A. Entomological News 116:61–74.

Mayr, G. 1861. Die europäischen Formiciden. Vienna: C. Gerolds Sohn, 80 pp.

Roger, J. 1859. Beiträge zur Kenntniss der Ameisenfauna der Mittelmeerländer. Berliner Entomologische Zeitschrift 3:225–259.

Smith, D. R. 1979. In Catalog of Hymenoptera in America north of Mexico. Smithsonian Institution Press, Washington D.C. Vol. 2, pp. 1323–1427.

Smith, M. R. 1951. Family Formicidae. Pp. 778–875 in: Muesebeck, C. F. W.; Krombein, K. V.; Townes, H. K. (eds.) 1951. Hymenoptera of America north of Mexico. Synoptic catalogue. United States Department of Agriculture. Agriculture Monograph 2.

Smith, M. R. 1967. Family Formicidae. Pp. 343–374 in: Krombein, K. V.; Burks, B. D. (eds.) 1967. Hymenoptera of America north of Mexico. Synoptic catalog. Second supplement. United States Department of Agriculture. Agriculture Monograph 2 (suppl. 2).

Wheeler, W. M. 1904. A new type of social parasitism among ants. Bulletin of the American Museum of Natural History 20:347–375.

Wheeler, W. M. 1910. Ants: their structure, development and behavior. New York: Columbia University Press, xxv + 663 pp.

Links
BugGuide-Amblyopone pallipes - mostly images of live specimens
AntWeb Images
Antwiki