Genus Lasius (Subfamily Formicinae) - Online Catalog of Ants of North America

Genus Lasius (Acanthomyops) (Formicinae)

Acanthomyops

OVERVIEW. The ants of this exclusively North American genus nest in the soil, usually beneath objects, and also in rotting logs and stumps. They are mostly subterranean in habit. During the marriage flight the workers come to the surface in large numbers, but this is the only time they are easy to find above ground. The females and workers have a characteristic citronella or lemon-verbena odor, and this can be used in the field to tell Acanthomyops from some similar species in genus Lasius. Several species have peculiar looking females that are believed to be temporary social parasites (see Wing, 1968a: 24-29 and Cover & Sanwald, 1988., in Trager (ed.) Advances in Myrmecology: 405-417 for discussions on the colony formation within the genus). Nest founding queens are exceptionally difficult to find within a mature nest, but alates may be taken at lights at night or on the ground during the mating flight.
NOMENCLATURE. Acanthomyops was considered a subgenus of Lasius prior to 1950. It had status as a full genus from 1950 to 2005, when it reverted back to a subgenus of Lasius.

Photo of Lasius californicus Wheeler. Courtesy of Ant Web, U. of Calif. Davis

RECOGNITION. Acanthomyops is found throughout the USA and is often common but little noticed. These exclusively subterranean ants are rarely found above ground except during the nuptial flight. In the field, a disturbed colony can often be identified by the strong lemon verbena or citronella odor that is emitted as a defensive chemical. Some species of Lasius have a similar odor, but it is much weaker. Acanthomyops can be distinguished from other Nearctic genera in subfamily Formicinae by the following combination of characteristics: Total length 2.5-5.5 mm. Body usually shining. Yellow, yellowish red, or orange subterranean ants. Palpal formula 3, 4. Maxillary palp short. Eye small; width usually half that of last antennal segment. Mesopropodeal spiracles often prominent and conspicuous. Propodeum with declivitous face usually only a little longer than the basal face. Basal face usually flat and evenly rounds into the declivitous face (i.e. there is no "Lasius peak").

Figure of Acanthomyops claviger from Smith, M.R. 1965.

SIMILAR SUBGENERA. Acanthomyops is most similar to the species of Lasius in subgenera L. (Cautolasius) and L. (Chthonolasius). The ants in all three groups are subterranean and share common morphological adaptations to underground life: reduced eye size and pale red or yellow body color. Acanthomyops is distinguished by its maxillary palp being 3-segmented and short. Acanthomyops belongs to a group of genera all having similar size and general appearance. The following table is a quick guide to separating them, but the beginning student is cautioned to carefully key out all specimens and then compare them to reliably identified material.

Acanthomyops	Maxillary palp short. Pale red subterranean ants.
Lasius	Propodeum with "Lasius peak." Mandibles with 7 or more teeth.
Myrmecocystus	Maxillary palp extremely long. Ants of the desert or arid areas.
Paratrechina	Dark, coarse, bristle-like hairs (absent in a few subterranean species). Scapes long.
Prenolepis	Mesosoma with distinct hourglass shape when viewed from above. Body smooth and very shiny.

SPECIES IDENTIFICATION. Use the "Shorter Key" in Wing, 1968a: 53-55 to key to species.
REVISIONS. Emery, 1893k: 638, 642 .— Wheeler, W.M. 1916o: 170–172.— Buren, 1950: 184–190 (key to queens - out of date) .— Wing, 1968a: 1–173 (keys to w.q.m, each species is described with figures (lateral view and full face view of head) plus natural history notes for many species) .
TAXONOMY. Smith, M.R. 1943e: 318 (brief description of m.) .— Smith, M.R. 1947f: 611–612, pl. 20, fig. 78 (description w.) .— Creighton, 1950a: 426–434, pl. 54, figs. 1–4 (figures (lateral view) w.q.m., wing) .— Wheeler, G.C. & Wheeler, J. 1953c: 154–156 (larvae) .— Wheeler, G.C. & Wheeler, J. 1970b: 648 (revised description l.) .— Umphrey, 1998: 431–440 (hybridization) .—Bolton, 2003: 275.
MISCELLANEOUS. Kannowski, 1963: 74–102 (flight activities) .— Talbot, 1963: 549–555 (local distribution and flight activities) .— Hölldobler, B. & Wilson, 1990: 153, 246, 251, 261, 263, 264, 267, 295, 358, 489, 527 (alaram and defensive chemicals) .
ALL REFERENCES

Lasius (Acanthomyops) arizonicus Wheeler. Most collections have been from under stones in an altitude range of 5000 to 8500 feet (Smith, D.R. 1979: 1440). Virtually nothing is known of their natural history.

arizonicus. Lasius (Acanthomyops) interjectus subsp. arizonicus Wheeler, W.M. 1917a: 532 (w.) . [USA, AZ, Cochise Co.; MCZ] Wing, 1968a: 90 (q.m.) . Combination in Acanthomyops: Creighton, 1950a: 431. Raised to species: Buren, 1950: 184. Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Southern AZ, southwestern NM, western TX. In southern Arizona, this is the most abundant member of this genus (S.P. Cover, personal communication).
RECOGNITION. This is an easily recognized species characterized by: pubescence on body almost absent, surface of body shining, and hairs sparse and long.
TAXONOMY. Wheeler, W.M. 1917a: 532–533 (comparison with californicus, coloradensis, and interjectus) .— Creighton, 1950a: 431 .— Wing, 1968a: 90–92, figs. 68–76 (description w.q.m., figures (lateral & full face view) w.q.) .
MISCELLANEOUS. Cokendolpher & Francke, 1990: 37 (first record in TX, brief natural history) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) bureni (Wing). This ant is known only from the type collection in Wisconsin.

bureni. Acanthomyops bureni Wing, 1968a: 135, figs. 159–167 (w.q.m.) . [USA, WI, Barron Co.; MCZ, USNM, Cornell University] Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

ALL REFERENCES

Lasius (Acanthomyops) californicus Wheeler. Colonies have been found in soil under stones in mountains at mid-elevations (Smith, D.R. 1979: 1440). Nothing is known of their natural history.

californicus. Lasius (Acanthomyops) interjectus subsp. californicus Wheeler, W.M. 1917a: 531 (w.q.) . [USA, CA, Los Angeles Co.; MCZ] Wing, 1968a: 85 (m.) . Combination in Acanthomyops and subspecies of claviger: Creighton, 1950a: 430. Raised to species: Buren, 1950: 185. Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Southern CA and northwestern NV.
TAXONOMY. Creighton, 1950a: 430 .— Wing, 1968a: 85–88, figs. 55–63 (description w.q.m., figures (lateral & full face view) w.q.) .— Wheeler, G.C. & Wheeler, J. 1986g: 68 (first record from outside of CA) .
MISCELLANEOUS. MacKay, Lowrie, et. al. 1988: 104 (occurrence in NM) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) claviger (Roger). This species is found in woodlands, pastures, or open fields where they nest under stones, in rotting wood, and occasionally in exposed soil (Smith, D.R. 1979: 1440). Along with interjectus, these are the two most common members of the genus in the east (S.P. Cover, personal communication).

claviger. Formica clavigera Roger, 1862a: 241, pl. 1, fig 13 (q.) . [USA, PA; Berlin] Mayr, G. 1870b: 950 (w.m.) . Combination in Acanthomyops: Mayr, 1862: 700; in Lasius: Mayr, 1870b: 950; in Lasius (Acanthomyops): Emery, 1893k: 642; in Acanthomyops: Donisthorpe, 1916e: 276; in Lasius (Acanthomyops): Ward, 2005a: 13.
parvula. Lasius (Acanthomyops) parvula Smith, M.R. 1934f: 213 (w.) . [USA, IL, Williamson Co.] Combination in Acanthomyops: Creighton, 1950a: 432. Synonymy: Wing, 1968a: 67 .

DISTRIBUTION. Southern New England west to MN and IA and south to TN and NC. West of MN and KS, it is replaced by coloradensis.
TAXONOMY. Buren, 1944a: 296, 298 (brief natural history) .— Creighton, 1950a: 429 .— Smith, M.R. 1965: 86–87, fig. 47 (description w., figure (lateral view) w., natural history) .— Regnier & Wilson, 1968: 86–87, fig. 47 (description w., figure (lateral view) w., natural history) .— Wing, 1968a: 67–78, figs 19–27 (description w.q.m., figures (lateral & full face view) of w.q.) .— Warren & Rouse, 1969: 57 (diagnosis of worker, habitat, distribution in AR) .
MISCELLANEOUS. Wheeler, W.M. & McClendon, 1903: 149–155.— Wheeler, W.M. 1905j: 398 .— Dennis, 1938: 296–297 (brief natural history) .— Rau, 1945: 119.— Carter, 1962b: 199 (habitat, distribution in NC) .— Gregg, R.E. 1963: 481 .— Talbot, 1963: 549–557 (local distribution, flight activities) .— Smith, M.R. 1965: 86–87 (description of w., natural history) .— Talbot, 1973: 20–21 (mating flight) .— Hölldobler, B. & Wilson, 1990: 247, 251, 261, 295, 320 (alarm and defensive chemicals) .— Umphrey & Danzmann, 1998: 431–440 (hybridization with A. latipes) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) colei (Wing). This is an uncommon species and virtually nothing is known of its natural history.

colei. Acanthomyops colei Wing, 1968a: 88, figs. 64–67 (w.m.) . [USA, AZ, Cochise Co.; MCZ, USNM] Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. New Mexico and Arizona. Only a handfull of collections of this species have been made.
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) coloradensis Wheeler. Most colonies have been found under stones. Western specimens often confused with A. claviger in earlier literature, but the two species have disjoint ranges (Smith, D.R. 1979: 1441).

coloradensis. Lasius (Acanthomyops) interjectus subsp. coloradensis Wheeler, W.M. 1917a: 532 (w.q.m.) . [USA, CO, El Paso Co.; MCZ] Combination in Acanthomyops and subspecies of claviger: Creighton, 1950a: 429. Raised to species: Buren, 1950: 185. Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Western North America.
TAXONOMY. Wheeler, W.M. 1917a: 532 (comparison with californicus and interjectus) .— Creighton, 1950a: 429–430 .— Wing, 1968a: 78–85, figs. 46–54 (description w.q.m., figures (lateral & full face view) w.q.) .
MISCELLANEOUS. Gregg, R.E. 1963: 481, 483–484 .— Wheeler, G.C. & Wheeler, J. 1963: 195–197 (diagnosis of w., habitat, distribution in ND, reported as claviger; misidenfication: Wing, 1968a: 83) .— Wheeler, G.C. & Wheeler, J. 1986g: 68 (brief natural history) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) creightoni (Wing). This species is known only from the type collection in Utah.

creightoni. Acanthomyops creightoni Wing, 1968a: 141, figs. 177–185 (w.q.m.) . [USA, UT, Grand Co.; MCZ] Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

Lasius (Acanthomyops) interjectus Mayr. This ant is found in woodlands, pastures or meadows. They may nest in exposed soil where the nest is sometimes surmounted by a mound, under stones or other objects, in rotting logs and stumps, or next to foundation walls of buildings (Smith, D.R. 1979: 1441). Along with claviger, these are the two most common members of the genus in the east (S.P. Cover, personal communication).

interjectus. Lasius interjectus Mayr, G. 1866b: 888, pl. 20, fig. 3 (q.) . [USA, NJ; Naturhistoriska Rikmuseum, Stockholm, Sweden] Emery, 1893k: 642 (w.) . Combination in Lasius (Acanthomyops): Emery, 1893k: 642; Wheeler, W.M. 1917a: 531; in Acanthomyops: Creighton, 1950a: 430; in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Roughly similar to the combined distribution of claviger and coloradensis. Coast to coast in the northern USA. In the west there is a southern extension to NM in the Rocky Mountain region and a similar southern extension follows down the Appalachian Mountains to the eastern Gulf States. It is abundant, however, only in the central and northeastern states (Creighton, 1950a: 430).
TAXONOMY. Wheeler, W.M. 1916r: 592, 594 .— Buren, 1944a: 296, 298 (brief natural history) .— Smith, M.R. 1947f: pl. 20, fig. 78 (figure (lateral view) w.) .— Creighton, 1950a: 428, 430 (distribution, nests) .— Smith, M.R. 1965: 88–89, fig. 49 (description w., figure (lateral view) w., natural history) .— Wing, 1968a: 92–97, figs. 77–84 (description w.q.m., figures (lateral & full face view) w.q.) .— Warren & Rouse, 1969: 57 (diagnosis of worker, habitat, brief natural history, distribution in AR) .— Hölldobler, B. & Wilson, 1990: 132 (figure (lateral view)of w.) .
MISCELLANEOUS. Wheeler, W.M. 1905j: 397–398 .— Wheeler, W.M. 1917a: 531 (distribution) .— Smith, M.R. 1928: 14–18.— Dennis, 1938: 296 (brief natural history) .— Groskin, 1947: 67–72.— Carter, 1962b: 199 (habitat; distribution in NC) .— Gregg, R.E. 1963: 484–486 .— Talbot, 1963: 549–557 (local distribution, flight activities) .— Wheeler, G.C. & Wheeler, J. 1963: 197–200 (diagnosis of w., habitat, distribution in ND) .— Smith, M.R. 1965: 88–89 (economic importance) .— Hangartner, 1969: 1–4 (trail laying) .— Talbot, 1973: 22 (natural history) .— MacKay, Lowrie, et. al. 1988: 104 (occurrence in NM) .— Cokendolpher & Francke, 1990: 37 (brief natural history) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) latipes (Walsh). This ant is found in open woodlands, meadows, or pastures where they may nest in exposed soil commonly surmounted by a mound, under stones or other objects, or at the base of stumps (Smith, D.R. 1979: 1441). The females are very unusual looking. This is the most abundant member of the genus in Colorado (Gregg, 1963: 488) and in southern Michigan (Talbot, 1973: 22).

latipes. Formica latipes Walsh, 1863: 311 (w.q.m.) . [q: USA, MI, Livingston Co.; MCZ] Combination in Lasius: Mayr, 1866b: 889; in Lasius (Acanthomyops): Emery, 1893k: 642; in Acanthomyops: Creighton, 1950a: 431; in Lasius (Acanthomyops): Ward, 2005a: 13. Note that the original citation is not "Walsh, 1862" as in Smith, D.R. 1979: 1441.

DISTRIBUTION. Coast to coast in the northern USA and extreme southern Canada. Southern extensions in the Rocky Mountains reaching northern NM. In the east, it is rare south of the latitude of PA (adapted from Creighton, 1950a: 431).
TAXONOMY. Emery, 1893k: 638, 642 .— Wheeler, W.M. & McClendon, 1903: 149–155.— Wheeler, W.M. 1916r: 592 .— Buren, 1944a: 296, 298 (brief natural history) .— Creighton, 1950a: 429, 431 (distribution, diagnosis of q.) .— Cole, A.C. 1954g: 284.— Smith, M.R. 1965: 91–93, fig. 50 (description w., figure (lateral view) w., natural history) .— Wing, 1968a: 98–105, figs. 86–94 (description w.q.m., figures (lateral & full face view) w.q., hybrids described) .
MISCELLANEOUS. Wheeler, W.M. 1905j: 398 .— Wheeler, W.M. 1917a: 398 (distribution) .— Mallis, 1941: 79.— Gregg, R.E. 1963: 486–488 .— Talbot, 1963: 549–557 (local distribution, flight activities) .— Wheeler, G.C. & Wheeler, J. 1963: 200–202 (diagnosis of w., habitat, distribution in ND) .— Smith, M.R. 1965: 91–93 (economic importance) .— Cole, A.C. 1966b: 20 (Nev. Test Site) .— Talbot, 1973: 22 (by far the most abundant member of the genus at the study site in southern MI, natural history) .— Wheeler, G.C. & Wheeler, J. 1986g: 68–69 .— MacKay, Lowrie, et. al. 1988: 104 (occurrence in NM) .— Cokendolpher & Francke, 1990: 37–38 (brief natural history) .— Hölldobler, B. & Wilson, 1990: 443.— Umphrey & Danzmann, 1998: 431–440 (hybridization with A.claviger) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) murphyi Forel. This ant usually nests under or next to stones in open woodlands or edges of woodlands. It prefers sandy soil. In the west it often occurs in cottonwood groves near stream bottoms. It is widely but sporadically distributed in North America (Smith, D.R. 1979: 1441) but is considerably less common than claviger, intejectus, or coloradensis. The females are very unusual looking. See Cover & Sanwald, 1988 (in Trager (ed.) Advances in Myrmecology) for a fascinating account of colony founding.

murphyi. Lasius (Acanthomyops) murphii Forel, 1901j: 367 (w.q.m.) . [USA, NC, Burke Co.; Forel Collection, Museum d'Histoire Naturelle, Geneva] Justified emendation of spelling to murphyi: Wheeler, W.M. 1905j: 398. Combination in Acanthomyops: Creighton, 1950a: 431; in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Coast to coast in extreme southern Canada and northern USA. Southern extensions down the Rocky Mountains to NM and to GA in the Appalachian Mountains.
TAXONOMY. Creighton, 1950a: 431–432 .— Smith, M.R. 1965: 89–91, fig. 49 (description w., figure (lateral view) w., natural history) .— Wing, 1968a: 113–121, figs. 104–112 (description w.q.m., figures (lateral & full face view) w.q., hybrids described) .
MISCELLANEOUS. Wheeler, W.M. 1905j: 398 .— Wheeler, W.M. 1917a: 530 (distribution) .— Carter, 1962b: 199 (brief natural history, habitat, distribution in NC) .— Gregg, R.E. 1963: 489–490 .— Talbot, 1963: 549–557 (local distribution, flight activities, misidentification - see Talbot, 1973: 21) .— Wheeler, G.C. & Wheeler, J. 1963: 202 (brief natural history) .— Sanwald, 1966: 81.— Talbot, 1973: 21 (queens flood the entrances to L. neoniger nests in large numbers ) .— Cover & Sanwald, 1988: 405–417 (detailed observations in field and laboratory settings on colony founding) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) occidentalis Wheeler. Nests have been found under stones in dry sandy soil (Smith, D.R. 1979: 1442). Little is known of its natural history of this rare ant.

occidentalis. Lasius (Acanthomyops) occidentalis Wheeler, W.M. 1909h: 83 (w.q.m.) . [USA, CO, El Paso Co.; MCZ] Combination in Acanthomyops: Creighton, 1950a: 432; in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. BC and WA east to MB and MN with a southern extension in the Rocky Mountains to NM (Wing, 1968a: 144).
TAXONOMY. Creighton, 1950a: 432, pl. 54, figs. 1–4 (figures w.q.m.) .— Wing, 1968a: 143–146, figs. 186–194 (description w.q.m., figures (lateral & full face view) w.q.) .
MISCELLANEOUS. Wheeler, W.M. 1917a: 530 (distribution) .— Gregg, R.E. 1963: 490–493 .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) plumopilosus Buren. This ant has been found under stones and in rotting logs (Smith, D.R. 1979: 1442). Nothing is known of its natural history. It has been misreported in the literature as claviger.

plumopilosus. Lasius (Acanthomyops) plumopilosus Buren, 1941b: 231, fig. 1 (w.q.m.) . [USA, IA, Delaware Co.; USNM, MCZ] Combination in Acanthomyops: Creighton, 1950a: 433; in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. Patchy distribution. NC, MI, MN, IA. This is a rare species that is easily confused with claviger.
TAXONOMY. Creighton, 1950a: 433 .— Wing, 1968a: 132–135, figs. 150–158 (description w.q.m., figures (lateral & full face view) w.q.) .
MISCELLANEOUS. Buren, 1944a: 296, 299 .
ALL REFERENCES

Lasius (Acanthomyops) pogonogynus Buren.

pogonogynus. Lasius (Acanthomyops) pogonogynus Buren, 1950: 186 (w.q.) . [USA, CO, Larimer Co.; USNM, MCZ] Combination in Acanthomyops: Wing, 1968a: 117. According to Wing, 1968a: 117, A. pogonogynus is a hybrid of A. murphyi and A. latipes; the name is not, however, formally synonymised. Combination in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. IA, CO, ID.
TAXONOMY. Wing, 1968a: 117–119 (as a hybrid) .
MISCELLANEOUS. Gregg, R.E. 1963: 493–494 .

Lasius (Acanthomyops) pubescens Buren. Nests with low mounds were found in soil in open woods (Smith, D.R. 1979: 1442).

pubescens. Lasius (Acanthomyops) pubescens Buren, 1942: 405 (w.q.) . [USA, MN, Crow Wing Co.; MCZ, USNM, Iowa State University] Combination in Acanthomyops: Creighton, 1950a: 433; in Lasius (Acanthomyops): Ward, 2005a: 13.

DISTRIBUTION. MN. Only two collections of this species have been made.
TAXONOMY. Creighton, 1950a: 433 .— Wing, 1968a: 138–140, figs. 168–176 (description w.q.m., figures (lateral & full face view) w.q.) .
ALL REFERENCES
PHOTOS.

Lasius (Acanthomyops) subglaber Emery. Nests are found in woodlands or open areas. It may construct mound nests or nest under stones, or in or under rotting logs and stumps (Smith, D.R. 1979: 1442).

subglaber. Lasius (Acanthomyops) claviger var. subglaber Emery, 1893k: 642 (w.q.m.) . [USA, DC; AMNH] Wheeler, G.C. & Wheeler, J. 1953c: 155, pl. III, figs. 22–26 (l.) . Combination in Acanthomyops: Creighton, 1950a: 433; in Lasius (Acanthomyops): Ward, 2005a: 13. Status as subspecies of claviger: Wheeler, 1917a: 533; raised to species: Creighton, 1950a: 433.
clavigeroides. Lasius (Acanthomyops) clavigeroides Buren, 1942: 406 (w.q.m.) . [USA, WI, Douglas Co.] Subspecies of subglaber: Buren, 1950: 185. Synonymy: Creighton, 1950a: 433 .

DISTRIBUTION. Saskatchewan and the Black Hills of SD east to central ME and southern NY. Southern extension into eastern NC and northern GA. Uncommon in the western part of its range.
TAXONOMY. Wheeler, W.M. 1905j: 398 .— Wheeler, W.M. 1917a: 533 .— Buren, 1950: 185 .— Wing, 1968a: 121–130, figs. 132–140 (description w.q.m., figures (lateral & full face view) w.q., hybrids described) .— Wheeler, G.C. & Wheeler, J. 1970b: 648, fig. 1 (larva) .
MISCELLANEOUS. Wheeler, W.M. 1908i: 623 .— Wheeler, G.C. & Wheeler, J. 1963: 203–204 (diagnosis of w., habitat, distribution in ND) .— Talbot, 1973: 19–20 (natural history) .
ALL REFERENCES
PHOTOS.