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) .
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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) .
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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.

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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) .
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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) .
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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.
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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) .
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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) .
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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) .
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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) .
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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 .
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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 .
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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.) .
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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) .
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PHOTOS.

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.

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) .
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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) .
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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.

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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) .
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PHOTOS.

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) .
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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.
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PHOTOS.

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) .
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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.

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) .
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PHOTOS.

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) .
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PHOTOS.

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) .
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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 .
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PHOTOS.

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 .
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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.) .
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PHOTOS.

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) .
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PHOTOS.

Genus Lasius (Cautolasius) (Formicinae)

Cautolasius Wilson, 1955a: 13 (as subgenus of Lasius) . Type species: Formica flava Fabricius, by original designation. Cautolasius provisional junior synonym of Lasius: Brown, 1973b: 179 (unconfirmed).

OVERVIEW. The workers in this subgenus are very similar to subgenus Chthonolasius in having light body color, reduced eye size, and shortened maxillary palps. However, these are judged to be convergent adaptations to a subterranean mode of life. Species of Cautolasius do not have parasitic colony formation and their queens are much more similar to subgenus Lasius than Chthonolasius since the head is small relative to the mesosoma. In all three castes the metapleural gland opening is as large as in subgenus Lasius (Wilson, 1955a: 13).

Photo of Lasius flavus (Fabricius) from AZ, Cochise Co. (Photoshop enhanced). Courtesy of Ant Web, U. of Calif. Davis

RECOGNITION. Maxillary palps medium length, 6-segmented, last 3 segments subequal in length. Eye very small; not more than 6 facets in greatest diameter and less than 35 facets total. Color light yellow to yellowish brown. Metapleural gland opening not reduced; greatest width of the gland opening measured perpendicular to its long axis is greater than the maximum width of the propodeal spiracle (including darkened rim).
SIMILAR SUBGENERA. These ants are easily confused with subgenus Chthonolasius which have a slightly larger eye and a reduced metapleural gland opening. Genus Acanthomyops has 3-segmented maxillary palps. Subgenus Lasius can be separated from subgenus Cautolasius by the following characteristics: eye much larger and a longer terminal segment of the maxillary palps (Lasius (Lasius) sitiens is an exception to the maxillary palp criteria).
REVISIONS. Wilson, 1955a: 13, 111–138 .
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Lasius (Cautolasius) fallax Wilson. Colonies have been found under stones in forest clearings (Smith, D.R. 1979: 1437).

fallax. Lasius (Cautolasius) fallax Wilson, 1955a: 130 (w.q.m.) . [USA, UT, (Bassets Spring); Creighton Collection, MCZ]

DISTRIBUTION. Rocky Mountains and Great Basin from MT and WA south to AZ (Wilson, 1955a: 130).
TAXONOMY. Gregg, R.E. 1963: 473 (considers L. fallax to be an unrecognizable taxon) .
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PHOTOS.

Lasius (Cautolasius) flavus (Fabricius). This is a subterranean ant which nests in various situations but most often under stones. It is known to build mounds in parts of Eurasia. Workers may attend aphids on roots of grasses (Smith, D.R. 1979: 1437). This is a common species throughout eastern USA south to the mountains of NC and TN. It is rare in the Gulf States (Wilson, 1955a: 125-126). In populations in Great Britain, nest found is pleometrotic (the young queens form groups in which they start a colony together). The coexisting queens groom each other and so prevent fungal infections that may kill solitary queens. However, once the first workers eclose and start foraging, the extra queens are eliminated and mature colonies are generally monogynous (have a single queen) (Waloff, 1957. Insectes Soc. 4: 391-408).

flavus. Formica flava Fabricius, 1782: 491 (w) . [Europe] Latreille, 1798: 42 (q.m.) . Combination in Lasius: Mayr, G. 1861: 50; Emery, 1925d: 231; Kuznetsov-Ugamsky, 1929b: 36; in Donisthorpea: Donisthorpe, 1915f: 216; in Formicina: Emery, 1916a: 241; in Acanthomyops: Forek, 1916: 460; Kuznetsov-Ugamsky, 1927e: 187; in Lasius (Chthonolasius): Ruzsky, 1914a: 59; in Chthonolasius: Ruzsky, 1925a: 288; Ruzsky, 1936: 90; in Lasius (Cautolasius): Wilson, 1955a: 112. Note that the publication date of the original citation is not "Fabricius, 1781" as in Smith, D.R. 1979: 1437.
brevicornis. Lasius brevicornis Emery, 1893k: 639, pl. 22, fig. 22 (w.q.m.) . [USA] Synonymy: Wilson, 1955a: 112 .
fuscoides. Lasius flavus var. fuscoides Ruzsky, 1902e: 16 (w.) . [Russia] Combintaion in L. (Chthonolasius): Ruzsky, 1914a: 61; in Chthonolasius: Ruzsky, 1925a: 288; in Acanthomyops: Kuznetsov-Ugamsky, 1927e: 187. Note that the original citation is not "Ruzsky, 1902. Schrift. Naturforsch. Gesell. Univ. Kasan. 38: 281" as in Smith, D.R. 1979: 1437. Synonymy: Wilson, 1955a: 112 .
odoratus. Lasius flavus var. odoratus Ruzsky, 1905b: 282 (w.) . [Russia] Note that the original citation is not "Ruzsky, 1902. Schrift. Naturforsch. Gesell. Univ. Kasan. 38: 282-283" as in Smith, D.R. 1979: 1437. Synonymy: Wilson, 1955a: 112 .
microps. Lasius (Formicina) brevicornis var. microps Wheeler, W.M. 1917a: 526 (w.) . [USA, CA, Mariposa Co.] Wheeler, G.C. & Wheeler, J. 1953c: 152 (l.) . Combintaion in L. (Chthonolasius): Creighton, 1950a: 422. Subspecies of brevicornis: Wheeler, G.C. & Wheeler, E.V. 1944: 253; of flavus: Creighton, 1950a: 422. Synonymy: Wilson, 1955a: 112 .
claripennis. Lasius (Formicina) flavus subsp. claripennis Wheeler, W.M. 1917a: 527 (w.q.m.) . [Canada, AB, (Banff)] Synonymy: Creighton, 1950a: 422 (claripennis junior synonym of microps) ; Wilson, 1955a: 112 (microps junior synonym of flavus) .
morbosa. Formicina flava var. morbosa Bondroit, 1918: 28 (w.q.) . [France] Junior synonym of flavoides: Emery, 1925d: 231. Synonymy: Wilson, 1955a: 112 .
apennina. Lasius (Chthonolasius) umbratus var. apennina Menozzi, 1925d: 34 (w.) . [Italy] Menozzi, 1932a: 8 (q.m.) . Variety of flavus: Menozzi, 1932a: 8. Note that the publication date of original citation is not "Menozzi, 1924" as in Smith, D.R. 1979: 1437. Synonymy: Wilson, 1955a: 112 .
ibericus. Lasius (Chthonolasius) umbratus st. ibericus Santschi, 1925g: 349, fig. 2 (w.) . [Spain] Synonymy: Wilson, 1955a: 112 .
sancho. Lasius (Chthonolasius) umbratus st. ibericus var. sancho Santschi, 1925g: 350 (w.) . Unavailable name. [Spain] Synonymy: Wilson, 1955a: 113 .
olivacea. Lasius (Lasius) flavus var. olivacea Karavaiev, 1926e: 194 (w.) . [Caucasus] Note that the original citation is not "Karawajew, 1926. Konowia 5: 194." as in Smith, D.R. 1979: 1437. Synonymy: Wilson, 1955a: 113 .
helvus. Lasius helvus Cook, T.W. 1953: 326, figs. (w.) . [USA] Synonymy: Wilson, 1955a: 113 .
helveolus. Lasius helveolus Cook, T.W. 1953: 327 (w.) . Incorrect subsequent spelling of Lasius (Chthonolasius) helvus Cook, 1953.

DISTRIBUTION. Nova Scotia, New Brunswick, Quebec south to AL west to Alberta, WA, OR, CA; Eurasia.
TAXONOMY. Cole, A.C. 1940b: 68–69.— Buren, 1944a: 296 .— Wilson, 1955a: 112–130, figs. 11–14 (description w.q.m., distribution) .— Wheeler, G.C. & Wheeler, J. 1963: 189–191 (diagnosis of w., habitat, distribution in ND) .— Bernard, 1967a: 359.— Wheeler, G.C. & Wheeler, J. 1970b: 651 (larva) .— Kutter, 1977c: 229.— Collingwood, 1979: 96, figs. 124–127 (diagnosis of w.q.m., figures (full face view) w.m., lateral view w., distributionin Scandanavia, natural history) .— Kupyanskaya, 1990a: 222.— Atanassov & Dlussky, 1992: 241.—Steiner, Schlick-Steiner, Schödle, et.al. 2004: 24–29.
MISCELLANEOUS. Wheeler, W.M. 1905j: 396 .— Gösswald, 1932: 1–156 (in Germany) .— Wesson & Wesson, 1940: 100.— Cole, A.C. 1942: 375 .— Wheeler, G.C. & Wheeler, E.W. 1944: 253.— Wilson, 1955a: 126–128 .— Waloff, 1957: 391–408 (nest founding, effect of number of queens on their survival and the development of first brood) .— Carter, 1962b: 197–198 (habitat, distribution in NC) .— Gregg, R.E. 1963: 465–469 .— Marikovsky, 1965: 63.— Wheeler, G.C. & Wheeler, J. 1973e: 117.— MacKay, Lowrie, et. al. 1988: 118 (occurrence in NM) .— Nielsen, 1992: 55–60 (changes in nest volume over time, in Denmark) .
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PHOTOS.

Lasius (Cautolasius) nearcticus Wheeler. This is a subterranean ant that prefers dense, moist woodlands here it nests in soil under rocks or fallen logs (Smith, D.R. 1979: 1438). It is common throughout most of the forested area from southeastern Canada to the southern Appalachian mountains (Wilson, 1955a: 135).

nearcticus. Lasius flavus subsp. nearcticus Wheeler, W.M. 1906f: 38 (w.q.m.) . [USA, IL; MCZ] Wheeler, G.C. & Wheeler, J. 1953c: 151 (l.) . Combination in L. (Chthonolasius): Creighton, 1950a: 422; in L. (Cautolasius) and raised to species: Wilson, 1955a: 133.
mellea. Formica mellea Provancher, 1881b: 356 (w.) . [Canada] Junior primary homonym (unresolved) of Formica mellea Say, 1836 (now in Camponotus). Also described as new by Provancher, 1883: 599. Synonymy: Francoeur & Béique, 1966a: 144.

DISTRIBUTION. Quebec, Ontario south to NC, TN, west to SD, WY, CO.
TAXONOMY. Cole, A.C. 1940b: 68, 70.— Buren, 1944a: 296, 297 .— Creighton, 1950a: 418, 422–423 (as L. flavus nearcticus) .— Wilson, 1955a: 133–136 (description w.qm., distribution) .— Gregg, R.E. 1963: 469–471 (taxonomic status, habitat, distribution in CO, as L. flavus nearcticus) .— Francoeur & Béique, 1966a: 144 (Provancher types) .
MISCELLANEOUS. Wesson & Wesson, 1940: 100.—Headley, 1943: 29.— Hicks, 1947: 170–171 (unusual nesting site) .— Wilson, 1955a: 135–136 .— Carter, 1962b: 198 (habitat, distribution in NC) .— Gregg, R.E. 1963: 469–471 .
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PHOTOS.

Genus Lasius (Chthonolasius) (Formicinae)

Chthonolasius Ruzsky, 1912: 630 (as subgenus of Lasius) . Type species: Formica umbrata Nylander, by subsequent designation of Emery, 1925d: 232. Chthonolasius subgenus of Lasius: Wheeler, W.M. 1922i: 698; Wilson, 1955a: 13. Provisional junior synonym of Lasius: Brown, 1973b: 179 (unconfirmed). Also described as new by Ruzsky, 1914a: 59. Note that the original spelling of the genus name is 'Chtonolasius'. 'Chthonolasius' is a justified emendation by Wheeler, W.M. 1916o: 170. Note that the publication date of the original citation not is "Ruzsky, 1913" as in Smith, D.R. 1979: 1438.

OVERVIEW. Ants of this subgenus are more subterranean than those of the subgenus Lasius, and some build large earthen mounds. Food is largely honeydew derived from subterranean plant lice and mealybugs. Some forms are temporary parasites on ants of the subgenus Lasius (Smith, D.R. 1979: 1438).

Photo of Lasius umbratus (Nylander) from CA, Nevada Co.. Courtesy of Ant Web, U. of Calif. Davis

RECOGNITION. Maxillary palps 6-segmented, short, last 3 segments subequal in length. Eye small; 10-12 facets in greatest diameter and more than 35 facets total. Color light yellow to yellowish brown. Reduced metapleural gland opening; greatest width of the gland opening measured perpendicular to its long axis is less than the maximum width of the propodeal spiracle (including darkened rim).

Figure of Lasius umbratus from Smith, M.R. 1965.

SIMILAR SUBGENERA. This group is easily confused with subgenus Cautolasius which has a slightly smaller eye and a normally developed metapleural gland opening. Genus Acanthomyops has 3-segmented maxillary palps.
REVISIONS. Wilson, 1955a: 150–192 .— Seifert, 1988a: 143–180 (European species) .— Seifert, 1990: 1–13 (supplement to 1988 revision of European species) .
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Lasius (Chthonolasius) atopus Cole. The nest of the type collection was found in dry soil under a stone in an unshaded area (Smith, D.R. 1979: 1438).

atopus. Lasius (Chthonolasius) atopus Cole, A.C. 1958a: 75, fig. 1 (w.) . [USA, CA, Mendecino Co.]

DISTRIBUTION. California.
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PHOTOS.

Lasius (Chthonolasius) humilis Wheeler. Colonies have been found under stones in moist soil of a meadow and in moist open woods (Smith, D.R. 1979: 1438).

humilis. Lasius (Formicina) humilis Wheeler, W.M. 1917a: 528 (w.q.) . [USA, NV, (Pyramid Lake); MCZ, LACM] Combination in: L. (Chthonolasius): Emery, 1925d: 233.

DISTRIBUTION. CO, NM, UT, NV.
TAXONOMY. Creighton, 1950a: 419, 423 .— Wilson, 1955a: 185–187 (description w.q., distribution) .— Gregg, R.E. 1963: 473–475 (habitat, distribution in CO) .
MISCELLANEOUS. MacKay, Lowrie, et. al. 1988: 118 (occurrence in NM) .
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PHOTOS.

Lasius (Chthonolasius) minutus Emery. This species is most often found in sphagnum bogs, swampy meadows, or open dry forests. Nests are most often in mounds or masonry domes. Some specimens have been associated with L. alienus (Smith, D.R. 1979: 1438).

minutus. Lasius umbratus subsp. minutus Emery, 1893k: 641 (w.q.m.) . [USA, NJ; Emery Collection, MCZ] Combination in: L. (Chthonolasius): Ruzsky, 1914a: 61. Subspecies of bicornis: Emery, 1925d: 233. Raised to species: Wilson, 1955a: 180.

DISTRIBUTION. Nova Scotia, ME south to VA west to MN, IA.
TAXONOMY. Wheeler, W.M. 1910h: 237, 238, 241–242 .— Wilson, 1955a: 180–182 (description w.q.m., distribution) .
MISCELLANEOUS. Gaige, 1914b: 3, 4, 21, 23.— Wheeler, W.M. 1915g: 206 .— Morris, R.L. 1944: 215.— Wilson, 1955a: 182 .—Kannowski, 1959: 162–165.— Kannowski, 1959b: 136–138, 151–153 (colony founding; possible parasitism on Lasius alienus and L. pallitarsis (= sitkaensis) .— Francoeur & Béique, 1968: 227–228 (Quebec) .
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PHOTOS.

Lasius (Chthonolasius) nevadensis Cole. Nests were found in an unshaded area in open forests; some were under stones and some were in exposed soil with a scattering of soil around the entrance (Smith, D.R. 1979: 1438).

nevadensis. Lasius (Chthonolasius) nevadensis Cole, A.C. 1956a: 26 (w.q.m) . [USA, NV, Clark Co.; USNM, MCZ, AMNH, Cole Collection]

DISTRIBUTION. NV (Kyle Canyon, Charleston Mts.).
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Lasius (Chthonolasius) speculiventris Emery. Nests have been found under rocks and in rotting wood either in pastures or wooded areas (Smith, D.R. 1979: 1438).

speculiventris. Lasius speculiventris Emery, 1893k: 641 (w.m.) . [USA, NJ, Essex Co.; MCZ, AMNH, USNM] Wilson, 1955a: 172 (q.) . Combination in L. (Chthonolasius): Emery, 1925d: 235. Subspecies of umbratus: Wheeler, W.M. 1910h: 237; Wheeler, W.M. 1917h: 167. Revived status as species: Creighton, 1950a: 423.

DISTRIBUTION. NJ, PA west to MN, IA, KS.
TAXONOMY. Wheeler, W.M. 1910h: 237, 242–243 .— Wheeler, W.M. 1916r: 592 .— Creighton, 1950a: 419, 423–424 .— Wilson, 1955a: 171–173 (description w.q.m., distribution) .
MISCELLANEOUS. Kannowski, 1959b: 138–141, 153–154 (parasitism on minutus and possible other Lasius spp.) .
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PHOTOS.

Lasius (Chthonolasius) subumbratus Viereck. Nests are under stones or rotting logs in meadows and forests. It is a temporary social parasite on the host, Lasius pallitarsis (Provancher) (Smith, D.R. 1979: 1439).

subumbratus. Lasius umbratus subsp. subumbratus Viereck, 1903: 73 (q.) . [USA, NM, San Miguel Co.; ANSP, MCZ] Wheeler, W.M. 1910h: 238 (w.m.) . Combination in L. (Chthonolasius): Emery, 1925d: 235. Raised to species: Creighton, 1950a: 424.

DISTRIBUTION. Nova Scotia, ME west to Saskatchewan, WA, OR south to NM, AZ.
TAXONOMY. Wheeler, W.M. 1910h: 237–239 .— Cole, A.C. 1942: 374 .— Creighton, 1950a: 419, 424 .— Wilson, 1955a: 179–180, fig. 17 (description w.q.m., distribution) .— Gregg, R.E. 1963: 475–478 (habitat, distribution in CO) .— Wheeler, G.C. & Wheeler, J. 1963: 191–192 (diagnosis of w., habitat, distribution in ND) .
MISCELLANEOUS. Wheeler, W.M. 1917a: 528 .— Wheeler, W.M. 1917h: 167–176 (nest founding with hosts L. pallitarsis and L. neoniger) .— Gregg, R.E. 1963: 475–478 .— MacKay, Lowrie, et. al. 1988: 119 (occurrence in NM) .
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PHOTOS.

Lasius (Chthonolasius) umbratus (Nylander). This ant prefers moist soil and most commonly nests under stones and in or under rotting logs and stumps. It may foster subterranean plant lice and mealybugs and is a temporary social parasite. Host: Lasius alienus (Foerster), L. niger (L.), L. neoniger Emery (?) (Smith, D.R. 1979: 1439).

umbratus. Formica umbrata Nylander, 1846b: 1048 (q.m.) . [Finland, (Helsinki); Helsinki Museum] Schenck, 1852: 59 (w.) . Combination in Lasius: Mayr, G. 1861: 50; in Donisthorpea: Donisthorpe, 1915f: 223; in Formicina: Emery, 1916a: 241; in Acanthomyops: Ruzsky, 1925b: 44; in Chthonolasius: Ruzsky, 1936: 91; in Lasius (Chthonolasius): Ruzsky, 1914a: 59; Müller, 1923b: 129; Emery, 1925d: 233; Wilson, 1955a: 150.
aphidicola. Formica aphidicola Walsh, 1863: 310 (w.q.m.) . [USA] Wheeler, G.C. & Wheeler, J. 1953c: 150 (l.) . Combination in Lasius: Mayr, 1886d: 429; in L. (Chthonolasius): Ruzsky, 1914a: 61. Junior synonym of flavus: Mayr, 1886d: 429. Revived from synonymy: Dalla Tore, 1893: 182. Variety / subspecies of umbratus: Wheeler, W.M. 1908k: 406; Buren, 1944a: 297. Note that the publication date of original citation is not "Walsh, 1862" as in Smith, D.R. 1979: 1439 and the original material is not "(w.m.)". Synonymy: Wilson, 1955a: 150 .
exacutus. Lasius umbratus var. exacutus Ruzsky, 1902d: 15 (w.) . [Russia] Combination in Acanthomyops: Ruzsky, 1925b: 44; in Lasius (Chthonolasius): Ruzsky, 1914a: 61; Emery, 1925d: 234. Subspecies of umbratus: Ruzsky, 1905b: 287. Raised to species: Ruzsky, 1925b: 44. Subspecies of bicornis: Menozzi, 1939a: 314 (in key). Note that the publication date of original citation is not "Ruzsky, 1904" as in Smith, D.R. 1979: 1439. Synonymy: Wilson, 1955a: 150 .
mixtoaffinis. Lasius umbratus var. mixtoaffinis Ruzsky, 1902d: 15. Nomen nudum. [Russia] Note that the original citation is not "Ruzsky, 1904. Kasan Univ. Obschchestvo estestvoispytatelei Protokoly Zasiedanii, no. 206, p. 15" as in Smith, D.R. 1979: 1439. Synonymy: Wilson, 1955a: 151 .
mixtobicornis. Lasius umbratus var. mixtobicornis Ruzsky, 1905b: 292. Nomen nudum. [Russia] Synonymy: Wilson, 1955a: 151 .
affinoumbratus. Lasius umbratus var. affinoumbratus Donisthorpe, 1914a: 40 (w.) . [Great Britain] Synonymy: Wilson, 1955a: 151 .
belgarum. Formicina belgarum Bondroit, 1918: 31, fig. 17 (w.q.) . [Belgium] Combination in Lasius (Chthonolasius): Emery, 1925d: 234. Variety of umbratus: Stärcke, 1937: 57; of mixtus: Stitz, 1939: 299. Synonymy: Wilson, 1955a: 151 ; Seifert, 1988a: 150 .
silvestrii. Lasius (Chthonolasius) silvestrii Wheeler, W.M. 1928d: 120 (q.) . [Japan] Synonymy: Wilson, 1955a: 152 .
hirtiscapus. Lasius umbratus var. hirtiscapus Stärcke, 1937: 43 (q.) . [Czechoslovakia] Variety of mixtus: Stitz, 1939: 299. Synonymy: Wilson, 1955a: 152 .
osakana. Lasius (Chthonolasius) silvestri (!) var. osakana Santschi, 1941: 278 (q.) . [Japan] Synonymy: Wilson, 1955a: 152 .
nyaradi. Chthonolasius affinis var. nyaradi Röszler, 1943: 47 (w.q.) . [Romania] Synonymy: Wilson, 1955a: 152 .
epinotalis. Lasius (Chthonolasius) umbratus subsp. epinotalis Buren, 1944a: 297 (w.) . [USA, IA, (Bellevue)] Synonymy: Wilson, 1955a: 152 .

DISTRIBUTION. Nova Scotia, New Brunswick, Quebec south to FL west to ID, UT, AZ.; Eurasia.
TAXONOMY. Wheeler, W.M. 1910h: 237–241 .— Wheeler, W.M. 1916r: 592 .— Stitz, 1939: 291.— Smith, M.R. 1947f: pl. 21. fig. 80 (figure (lateral view) of w., as L. umbratus mixtus aphidicola) .— Wheeler, G.C. & Wheeler, J. 1953c: 150, pl. III, figs. 9–16 (larva of L. umbratus aphidicola) .— Wilson, 1955a: 150–167, fig. 1, 15, 16 (figure (lateral view) of w.) .— Wheeler, G.C. & Wheeler, J. 1963: 192–194 (diagnosis of w., habitat, distribution in ND) .— Smith, M.R. 1965: 84–86, fig. 46 (description w., figure (lateral view) w., natural history) .— Bernard, 1967a: 363.— Kutter, 1977c: 232.— Collingwood, 1979: 101–102, figs. 139–142 (diagnosis of w.q.m., figures (lateral view) w., full face view q.m., distribution in Scandanavia, natural history) .— Seifert, 1988a: 150–152, figs. 6, 16, 25, 33, 53 (description w.q.m., brief natural history, distribution in Europe) .— Atanassov & Dlussky, 1992: 245.
MISCELLANEOUS. Wheeler, W.M. 1905j: 397 .— Smith, M.R. 1928c: 277–278.— Wesson & Wesson, 1940: 90, 101.— Wilson, 1955a: 161–165 .— Kannowski, 1959b: 141, 154–155 (possible parasitism on other Lasius spp) .— Carter, 1962b: 198 (habitat, distribution in NC) .— Gregg, R.E. 1963: 478–481 .
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PHOTOS.

Lasius (Chthonolasius) vestitus Wheeler.

vestitus. Lasius umbratus subsp. vestitus Wheeler, W.M. 1910h: 242 (q.) . [USA, ID, Latah Co.; MCZ] Wilson, 1955a: 174 (w.) . Combination in L. (Chthonolasius): Emery, 1925d: 235. Raised to species: Creighton, 1950a: 425.
pilosus. Lasius (Chthonolasius) pilosus Smith, M.R. 1934b: 384 (w.) . [USA, ID, (Moscow)] Synonymy: Wilson, 1955a: 173 .

DISTRIBUTION. BC, ID, OR, CA.
TAXONOMY. Creighton, 1950a: 425–426 .— Wilson, 1955a: 173–175 (description w.q.m., distribution) .
PHOTOS.

Genus Lasius (Acanthomyops)
URL: http://www.cs.unc.edu/~hedlund/playpen/dev/ants/catalog/
Last updated: Wed May 23 10:08:17 EDT 2007
Copyright 2006, Kye S. Hedlund, University of North Carolina, hedlund@cs.unc.edu