taxonID	type	description	language	source
03E5E90BFF892339FF3C9E4BFE1E759A.taxon	discussion	Wheeler (1907) established A. versicolor chisosensis from a number of workers taken by Judge O. W. Williams in the Chisos Mountains of southwestern Texas, and a few workers taken by himself at Terlingua, also in southwestern Texas. His new subspecies was differentiated from typical versicolor as being distinctly lighter and more yellowish in color, with much less pronounced sculpture and in having only a few (about 12) pointed tubercles on each side of the median gastral depression. Creighton (1950) pointed out that the number of gastral tubercles varies with the size of the worker in A. versicolor and small workers of both taxa have a similar number of tubercles. Fowler (1988) was of a similar view. Although additional collections from western Texas would be helpful, an examination of current holdings of A. versicolor has failed to convince us that Wheeler’s characters represent meaningful differences. The type material of A. chisosensis seems to represent little more than pale (likely faded) and lightly sculptured individuals of A. versicolor. Pending the discovery of evidence to the contrary, A. chisosensis is best regarded as a synonym of A. versicolor.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF892339FF3C9E4BFE1E759A.taxon	distribution	Acromyrmex versicolor is known from northern Mexico (including Baja California) and the United States (Arizona, California, Texas).	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF89233AFF3C9B1BFCE273F9.taxon	discussion	Aphaengaster boulderensis was described by Smith (1941) based on a series of workers from Sentinel Island (as Horseshoe Island), Lake Mead, Nevada. It is a distinctive member of the North American ant fauna, being one of the few Aphaenogaster species that lacks propodeal spines (the propodeal angle being rounded and with at most a pair of low ridges). It is also characterized by its relatively elongate head and mesosoma and yellowish-brown body color, with the gaster darker in some specimens.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF89233AFF3C9B1BFCE273F9.taxon	description	The subspecies A. boulderensis smithi was established by Greg (1949) for workers from the Valley of Fires (as the Malpais Lava Beds), near Carrizozo, New Mexico. Gregg noted it was different from typical A. boulderensis in having a longer and more tapered head, a more elongate mesosoma with a shorter propodeum, and heavier sculpturing giving it a more opaque appearance when compared to A. boulderensis. In addition, the propodeal angle has more noticeable ridges, it lacks a minute spine on the anteroventral surface of the petiole, and it is a richer red color with a uniformly black gaster (the black extending onto the postpetiole in some specimens). Neither A. boulderensis nor A. smithi is frequently collected and Aphaenogaster smithi has received little mention in the published literature since its description. However, the scanty material available provides little support for the separation of A. smithi and A. boulderensis. Of the characters used by Greg (1949), the shape of the head differs only slightly between specimens identified as belonging to these taxa (Fig. 1), with A. smithi specimens averaging slightly wider for a given head length when compared with A. boulderensis specimens. Likewise, mesosoma length, propodeal structure, and sculpture all show considerable overlap, especially in smaller specimens. Gaster color has also been reported as being useful in segregating specimens into two forms. However, this color pattern appears to form an east-west cline, with western populations (Arizona, Nevada) having the gaster similar in color to the mesosoma while more eastern specimens (Arizona, New Mexico, Texas, Chihuahua) have the gaster much darker red-black. Given the limited evidence, we believe these two morphs are most probably representatives of a single taxon, with western populations having a slightly narrower head and paler gaster while eastern forms have a slightly broader head and darker gaster. A. smithi is thus best regarded as a synonym of A. boulderensis.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF89233AFF3C9B1BFCE273F9.taxon	distribution	A. boulderensis is known from Mexico (Baja California, Chihuahua) and the United States (Arizona, California, Colorado, Nevada, New Mexico, Texas, Utah).	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8A233BFF3C9BE5FD8672DE.taxon	discussion	Emery (1895) established the infrasubspecific (and therefore unavailable) name “ Stenamma (Aphaenogaster) fulvum subsp. aquia var. aztecum ” for several workers from Mexico (specific locality not given and currently unknown). Enzmann (1947) was the first to use this name as a trinomial and thereby made the name available as Aphaenogaster fulva azteca. Emery (1895) separated his variety from others based on its very “ rough ” sculpturing, long and almost horizontal propodeal spines and dark black-brown body color with bright red legs. An image of a syntype is available on AntWeb (at www. antweb. org / specimen / CASENT 0904168) and single worker labeled as “ Aphaenogaster fulvum aquia var. aztecum Em, Mexico ” and “ from Emery ” and matching Emery’s description is held in the MCZC. While not labeled as a type it seems highly likely that if not a true type this specimen was certainly identified by Emery and is likely to be conspecific with the true type material.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8A233BFF3C9BE5FD8672DE.taxon	description	When comparing Emery’s specimen of A. azteca with A. fulva specimens, similar body color and development of sculpturing can be found in A. fulva specimens. However, darker A. fulva workers also have darker legs, which are similar in color to the body. In contrast, the legs in A. azteca are distinctly lighter in color compared to the body. Also, as noted by Emery, the propodeal spines in A. azteca are directed posteriorly (are nearly horizontal) while in A. fulva these spines are directed strongly upwards. These last two characters readily separate these two taxa. Finally, A. fulva is most abundant in the eastern and southeastern US although it is known from as far west as New Mexico (a doubtful record) and eastern Texas, but has been only rarely encountered there. A. azteca was collected from an unknown locality in Mexico, an area where A. fulva does not occur, or at least not commonly. These morphological and geographic differences strongly suggest that these two taxa are both distinct and we propose raising A. azteca to full species status.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8B233BFF3C9FDEFD5675B9.taxon	discussion	Creighton (1950) provides an exhaustive history of the name A. aquia. Buckley (1867) did not designate types, leaving us with little more than speculation as to what his name might represent. From the meager description, A. aquia could be any Aphaenogaster native to the northeast, excepting perhaps A. tennesseensis or A. treatae. Mayr (1886) believed it to be a synonym of A. fulva while Emery (1895) treated it as a subspecies of A. fulva. Creighton (1950) felt that what Emery called A. aquia was an intergrade between A. picea and A. rudis, both of which were considered to be subspecies of A. fulva at that time, with A. picea being the higher elevation form occurring in the Appalachian Highlands and A. rudis a lower elevation form found in the piedmont areas at the base of the Highlands. He concluded that “ We do not know what Buckley's aquia was. Emery's aquia appears to have been an intergrade which should never have been named. I propose, therefore, to place aquia in the list of unrecognizable forms. ” Subsequent authors followed Creighton’s lead and have left the name aquia alone for over 50 years.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8B233BFF3C9FDEFD5675B9.taxon	discussion	To permanently resolve the status of Buckley’s aquia we here designate a neotype. This specimen is conspecific with the currently accepted concept of A. fulva, and thus Myrmica (Monomorium) aquia Buckley becomes a junior synonym of A. fulva Roger.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8B233CFF3C98E6FAE5718C.taxon	discussion	Creighton (1950) considered A. occidentalis and A. valida to be geographic “ races ” of A. subterranea, the former occurring from California and Nevada northward through Oregon and Washington and into British Columbia while the latter occurred from Colorado and Wyoming northward into Montana and then west into southern British Columbia. He reported a broad area of integration between the two forms, from British Columbia, eastern Washington, northern Idaho and western Montana, where they showed greatly increased variability. He separated the two based on size, A. valida ranging up to 6 mm in length while A. occidentalis reaching only 4.5 mm, and color, A. valida being “ usually castaneous brown ” and A. occidentalis “ usually piceous brown. ” However, he noted that large numbers of workers were required to separate the two forms with certainty and that it was often impossible to identify isolated workers.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8B233CFF3C98E6FAE5718C.taxon	description	Little has changed since Creighton’s study. Examination of recent collections suggests that while western populations do average slightly smaller than eastern populations, there is considerable overlap, making reliable separation impossible. Color shows a similar pattern with geographic differentiation but considerable overlap. It seems apparent that these two forms are variants of a single variable species. We therefore consider A. subterranea valida Wheeler to be a junior synonym of A. occidentalis (Emery).	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8B233CFF3C98E6FAE5718C.taxon	distribution	This species is found from British Columbia south to California and east to Montana and Colorado.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8C233CFF3C9F2DFC0A75B9.taxon	discussion	Aphaenogaster huachucana crinimera was established by Cole (1953) based on a series of nests collected at two high-elevation sites in New Mexico. He stated that his new subspecies was apparently very closely related to A. huachucana but differed in having more prominent sculpturing, sharper and longer propodeal spines, more hairy legs and considerably darker body color. It is puzzling that Cole chose to associate his new subspecies with A. huachucana. The differences cited by Cole between A. huachucana and A. crinimera are real, but Cole overlooked the most important difference of all: A. crinimera lacks the prominent lobe at the base of the antennal scape that separates A. huachucana from all other North American congeners. In all other respects, A. crinimera is, frankly, inseparable from A. texana, the sole member of the Aphaenogaster rudis complex present throughout much of Arizona and New Mexico. Recent collections of A. texana show that the species varies in color from dark brown to reddish or yellowish brown, but is morphologically consistent across its range. The A. crinimera types are typical A. texana from a population on the darker side of the color spectrum. Because of this we consider A. crinimera to be a junior synonym of A. texana.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8C233CFF3C9F2DFC0A75B9.taxon	distribution	A. texana is found from Arkansas west through Texas, New Mexico and Arizona, and south into northern Mexico. Western populations typically occur in middle elevation mesic oak-pine forests. The ant is especially common in protected canyon slope and bottom forests that are not subject to flooding. Nests are in soil and litter and are most commonly found under rocks in dappled to moderate shade.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8C233DFF3C98E6FDED736C.taxon	discussion	Wheeler and Wheeler (1934) described several taxa as “ forms ” of A. treatae, basing their distinctions on minor differences in sculpture, color, pilosity, head shape, and the shape of the distinctive basal antennal flange that distinguishes A. treatae from its congeners. Aphaenogaster treatae pluteicornis was established based on material collected in Oklahoma and Texas while two varieties of A. pluteicornis, “ alabamensis ” (from Alabama) and “ oklahomensis ” (with the same type locality as A. pluteicornis) were also described. These last two names were established as infrasubspecific (quadrinomials) and are thus unavailable.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8C233DFF3C98E6FDED736C.taxon	description	Creighton (1950) was the first to consider these forms and reduced the number of valid taxa from four to two, treating “ alabamensis ” as a synonym of A. treatae and “ oklahomensis ” as a synonym of A. treatae pluteicornis. He separated A. treatae from A. treatae pluteicornis based on differences in head shape (longer and narrower and with the posterior margin narrower and flatter in A. pluteicornis) and sculpturing (longitudinal rugae present on the front of the head in A. treatae, only rarely present in A. pluteicornis). None of the differences cited by the Wheelers or by Creighton hold up, especially given the availability of new material collected in the Florida panhandle and in eastern Texas (in MCZC). In general, workers from southern populations are reddish brown to yellowish brown in color; workers from populations from North Carolina and north tend to be darker, commonly a medium to dark brown. Cephalic sculpture tends to be a bit more prominent in northern populations, but head shape, the differences in antennal flange shape, and pilosity cited by the Wheelers are not especially convincing. From this examination we conclude that A. treatae pluteicornis is best considered a synonym of A. treatae.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8C233DFF3C98E6FDED736C.taxon	distribution	Aphaenogaster treatae occurs from Maine south to the Gulf Coast (northern Florida) and west to eastern Texas, Oklahoma and north to Indiana and Illinois. Note that in the eastern states, A. treatae nests in well-drained, often sandy soils in open habitats. Nests are generally inconspicuous and are commonly found under grass clumps. In eastern Texas, the second author found the species in open, sometimes recently burned pine-oak forests and in small gaps in such forests. Of five collections, two were nests in soil, but three colonies were in red rotten pine branches or logs on the soil surface.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8D233EFF3C9E4DFDD075E5.taxon	discussion	Crematogaster missouriensis was described by Emery (1895) as a subspecies of C. victima, apparently on the recommendation of Pergande (as the original description attributes the name to him). Creighton (1939) correctly recognized that C. missouriensis was actually more similar to C. minutissima than C. victima and regarded it as “ northern race ” of C. minutissima, maintaining it as a subspecies but transferring it from C. victima to C. minutissima. Crematogaster smithi was described by Creighton (1939) using the name C. thoracica, not realizing that that name had previously been used by Santschi (1921). Creighton (1950) corrected this oversight by proposing the replacement name C. smithi, the name it has been known by since.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8D233EFF3C9E4DFDD075E5.taxon	description	The small queen species is clearly Mayr’s C. minutissima. Mayr gives the length of the syntype queen as 4.2 mm, which is decisive. A specimen of the original Pergande collection of C. missouriensis from Missouri is present in the MCZC (see Creighton, 1939). Its longer propodeal spines and lack of longitudinal rugae on the promesonotal dorsum matches Creighton's concept of C. missouriensis, separates it from C. minutissima, and therefore establishes it as a worker of the large queen species. It is here considered a full species in its own right and not a subspecies of C. minutissima. This leaves us with Crematogaster smithi. The worker of this ant was diagnosed as having a relatively smooth and shiny mesosomal dorsum compared to the dull surface supposedly found in close relatives, and as lacking longitudinal rugae on the pronotum (or when present they are lateral and wavy). In related species these rugae are well developed and more central on the pronotum. However, Creighton noted that the rugae in C. missouriensis are variable and can also occur laterally, but in these cases the rugae are more prominent than those found in C. smithi. Also, in dorsal view the petiole of C. smithi was described as diverging posteriorly and with the widest point near the insertion of the postpetiole while in C. minutissima and C. missouriensis the petiole is quadrate with subparallel sides, the widest point (when noticeable) being near the center. Finally, Creighton noted that the propodeal spines were short and in other respects this taxon was very similar to C. minutissima. An examination of recent collections has convinced us that the morphological characters cited by Creighton are all more variable than he suspected and that there is considerable overlap with C. missouriensis and C. minutissima. In addition, recent collecting has narrowed the distributional gap between these forms. C. smithi was described from specimens collected in Huachuca Mtns. in south-central Arizona. Since then, it has been found widely in Arizona, and two additional important collections have been made: one in the Davis Mtns of west Texas (including queens) and another from Roosevelt Co., New Mexico (both in MCZC). The Davis Mtns. collection clearly matches Creighton’s concept of C. missouriensis and the Roosevelt Co. specimens are a good match for his concept of C. smithi. This may seem confusing, but natural history comes to our rescue here. Queen size, colony structure, and ecology of C. smithi all closely match those of C. missouriensis.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8D233EFF3C9E4DFDD075E5.taxon	distribution	Our assessment of the evidence is that there are only two species: C. minutissima, and C. missouriensis. In the eastern and central parts of their range, where C. minutissima is present, the workers of C. missouriensis are fairly consistent morphologically and separable from those of C. minutissima. In the absence of C. minutissima (not present west of the Hill Country in central Texas), western populations display greater variation in worker morphology, a situation reminiscent of classical character displacement. However, the western populations are firmly linked to C. missouriensis by queen size, colony structure, and ecology. C. smithi, therefore, is best regarded as a synonym of C. missouriensis.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8E233FFF3C98C5FC167244.taxon	discussion	To say that North American ants of the Formica rufa species group have had a troubled taxonomic history is to indulge in a talent for understatement. In the late 19 th and early 20 th century, numerous names were generated by early taxonomists, with little reference to ecology, distributional data, comparative context, or sense. To be fair, most of these early workers were dealing with very limited material. Creighton (1940, 1950) was the first to attempt to make sense of the resulting hodgepodge of names. Since then, some infraspecfiic taxa have proven to be valid species, others have been synonymized, but a few problematic names remain. Formica clivia was described as a subspecies of F. r u f a (Creighton, 1940) and transferred to F. obscuriventris by Creighton (1950). Creighton delimited the subspecies based on color and pilosity and claimed distributional support: F. obscuriventris being primarily eastern, with a few high altitude populations in the southern Rockies; F. clivia being primarily western and being present at lower altitudes in the Rockies. An examination of material from over the entire enormous range of F. obscuriventris provides little support for Creighton’s scheme. Eastern populations vary in color, but do not show the deep infuscation present in some western populations. Colonies with heavily infuscated workers occur throughout much of the American west, but the infuscation is variable and colonies with little or no infuscation are not infrequently encountered. Pilosity in this species is notably variable, but it doesn’t seem to co-vary with color as Creighton thought. As such, there is little evidence to justify the maintenance of F. clivia as separate from F. obscuriventris. For these reasons, F. clivia is here synonymized with F. obscuriventris.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8E233FFF3C98C5FC167244.taxon	distribution	Formica obscuriventris is known from Canada (all southern provinces) and the United States (north from Oregon, Nevada, Utah, Colorado, South Dakota, Tennessee and Georgia).	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8F233FFF3C9F65FEF875E4.taxon	discussion	Wheeler (1913) described this taxon as a variety of F. oreas, stating that it was darker in color and more pilose than F. o re a s. Creighton (1950) could not confirm the pilosity differences but did find the darker color significant enough, when combined with the more northern distribution, to treat F. comptula as a subspecies of F. oreas. Syntype workers of F. comptula in the MCZC differ little in color or pilosity from collections of F. o re as from other parts of its range. However, Wheeler (1913) also described pilosity differences in the queen caste. These are far more noteworthy than the supposed differences in the workers. The syntype queens of F. comptula have longer, coarser, more erect, and more abundant pilosity than queens of typical F. o re a s. Queens from Arizona, Colorado, and Utah, all show typical shorter, fine-textured, “ silky ” F. oreas pilosity. Given the small amount of F. comptula material available, we provisionally interpret this as population level variation. Further collecting is needed to see whether queens from populations in the northern and far western states show pilosity like the F. comptula syntypes and if the variation is clinal rather than discrete. Pending better evidence, we feel it best to synonymize F. comptula with F. oreas at this time.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8F233FFF3C9F65FEF875E4.taxon	distribution	The known distribution of F ormica oreas includes Alberta, Canada and the following states in the US: Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, North Dakota, Oregon, Utah, Washington and Wyoming.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF8F233FFF3C98C5FC0B77C1.taxon	description	This species has been recorded from Illinois and Iowa, United States.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF802331FF3C9D9EFDB772FA.taxon	discussion	The taxonomic history of the forms centering on what is presently called Myrmica incompleta Provancher is a saga calculated to make the wicked laugh and the judicious weep. While contemplating this tangle, keep in mind that M. incompleta is a common ant in cold climates across Canada and the northern United States, from the Maritime Provinces west to Alaska, south to New England and the Great Lakes region, and with an enormous southern extension in the Rocky Mountains, Washington, Oregon, and the Sierra Nevada in California. Over this vast expanse its ecology and colony structure seem to be pretty consistent. It is an ant of moist, open or semi-open habitats, often forming dense populations at the edges of bogs, fens, and wet depressions in meadows. Colonies can be very large, are usually highly polygynous, and appear at times to form large, unicolonial populations. The workers vary in size more than in most Myrmica both within and between colonies, and show variation in sculpturing, propodeal spine length, and color. Because the ant is commonly collected, its variability attracted the attention of early ant taxonomists who, following the conventions of their times, named whatever variants they came across. The result was a jumble of taxon names based on small variations in color or sculpture. After much work by Creighton (1950) and Francoeur and Beique (1966), the complex is presently arranged as follows:	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF802331FF3C9D9EFDB772FA.taxon	discussion	Our concern here is with the name Myrmica whymperi Forel, which is still valid. The name was established as a variety of M. brevinodis by Forel (1913) but only a few years later Wheeler (1917) synonymized it with M. sulcinodoides. Creighton (1950) considered this complex and found that “ … it is necessary to synonymize the varieties canadensis, frigida, subalpina, sulcinodoides and whymperi with brevinodis … ” as the material he examined had shown “ … the impossibility of satisfactory separation on either a structural or a distributional basis. In every case the structural distinctions involved consist of exceedingly slight differences in sculpture, pilosity or color. ” Thus M. whymperi fell into synonymy with M. brevinodis. Unfortunately, Creighton’s perspicacity in this matter was not emulated by his successors. The next year Smith (1951), without comment, removed M. sulcinodoides from synonymy and placed it as a subspecies of M. brevinodis. He also transferred M. frigida and M. whymperi from synonymy with M. brevinodis to synonymy with M. brevinodis sulcinodoides. Francoeur & Beique (1966), while examining the type material of Provancher, realized that what Creighton (1950) had thought was M. brevinodis was actually Provancher’s M. incompleta. As a result M. brevinodis fell into synonymy with M. incompleta and M. frigida and M. whymperi became synonyms of M. incompleta sulcinodoides rather than M. brevinodis sulcinodoides. Mackay, Lowrie et al. (1988) treat M. sulcinodoides as a full species in their identification key although no discussion is given and no mention was made of how its synonyms should be treated. M. incompleta and M. whymperi (as M. sulcinodoides) are separated based on sculpture and color. Finally, Bolton (1995) recognized that while the name sulcinodoides had been used as the valid name for this taxon, in fact whymperi was the older name and had priority. Thus we arrived at the arrangement listed above. After examining numerous specimens from throughout the range of M. incompleta, and a syntype of M. whymperi present in the MCZC, we are certain that Creighton (1950) was correct. All of the taxa listed above are best regarded as variants of a single geographically widespread species. This includes M. whymperi. The syntype worker has slightly stronger sculpturing and longer propodeal spines than most examples of M. incompleta, but specimens with similar attributes are occasionally found in populations far from the M. whymperi type locality. In the absence of additional support for the significance of such differences, there is no reason at present to maintain M. whymperi as a distinct species in its own right.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF802331FF3C9D9EFDB772FA.taxon	distribution	Myrmica incompleta is known from southern Canada and the United States from Alaska and from California and Arizona north and east through Colorado, South Dakota and Illinois to Maine. It is the host for the xenobiotic social parasite Formicoxenus provancheri.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812331FF3C9FBAFC88777D.taxon	discussion	As noted by Watkins (1977), Nomamymrex esenbeckii has accumulated a large number of names to describe its various forms. The number of these names considered as valid has gradually decreased as additional material has revealed intermediate morphologies, diverse combinations of character states and distinct geographic patterns. As a result we are currently down to just a single species with two recognized subspecies, N. mordax and N. wilsoni (Watkins, 1977; Wild, 2007). However, even this relatively simple system has proven problematic. In a detailed but unpublished analysis, Roy and Gordon Snelling (http: // www. armyants. org / armyants / genusaccounts / nomamyrmex / noma. html, accessed 19 June 2014) provide the following notes:	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812331FF3C9FBAFC88777D.taxon	description	“ It is true that the morphological features on which the several subspecies of N. esenbeckii are based are generally representative of their respective populations. Equally true, however, is that many specimens within these populations do not possess the required characteristics of that named population. Samples from areas of sympatry are, as may be expected, intermediate between the respective phenotypes. In the worker caste, there is a north / south trend that is continuous. In northern specimens, the posterior margin of the mesonotum, in dorsal view, is definitely concave, and the longitudinal rugules of the propodeal dorsum are short and weak. Proceeding into Central America and through South America, the margin of the mesonotum becomes straight or even convex; the propodeal rugulae strengthen and run the entire length of the dorsal face. Similar trends are evident in the male structures employed by Watkins (1977) in segregating N. esenbeckii into four subspecies. In fact, differences in genitalic structures may be greater within any given population than those that separate purported subspecies. Under the circumstances, there would appear to be little justification for these subspecies and we propose to reduce all to synonymy. ” Wild (2007) accepted these recommendations when he synonymized N. crassicorne and we now apply this careful analysis by the Snellings to the remaining subspecies.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812331FF3C9FBAFC88777D.taxon	distribution	Nomamymrex esenbeckii is exceptionally widespread, occurring from southern Texas, United States, south through Central America to northern Argentina and Paraguay.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812332FF3C9A25FD0D744D.taxon	discussion	Smith (1934) described T. foveatus based on a single worker from Illinois. At the time he considered it “ so different from all of the Leptothorax [now Temnothorax] with which I am familiar that I am somewhat hesitant in trying to assign it to its proper taxonomical position. ” However, some time later he reconsidered this view and Creighton (1950) reports that Smith “ now regards the insect which he described as the species foveata in 1934 as very closely related to ambiguus if not actually a synonym of that species. ” We concur with Smith’s later interpretation and consider T. foveatus to be a synonym of T. ambiguus. Note that Smith had two workers of this taxon, one of which was clearly abnormal. The abnormal worker has been imaged and placed in the USNM’s Ant Type database. The description makes clear that Smith did not consider it a type. Excepting its deformity in the structure of the petiole and postpetiole, it is otherwise a typical worker of Temnothorax ambiguus.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812332FF3C9A25FD0D744D.taxon	description	Wesson & Wesson (1940) established T. ambiguus pinetorum from specimens collected in Ohio, separating it from T. ambiguus based on the longer propodeal spines and less conspicuous mesosomal rugae. The queen and male were also described, the queen being separated from the queen of T. ambiguus by its smaller body size and longer propodeal spines, while the male was reported as differing from T. ambiguus in being smaller and less hairy. Modern collecting has revealed T. ambiguus to be a geographically widespread species. There is variation in propodeal spine length, color, and queen size, and this is accompanied by comparable (but independent) geographic variation in nest site preference, colony size, and habitat selection. In the context of this bigger picture, the characters cited by Wesson & Wesson (1940) fall well within the observed variation in T. ambiguus. The types of T. pinetorum appear to come from a colony where the workers have somewhat longer propodeal spines and finer mesosomal sculpturing than average. Because of this we have no hesitation in considering T. pinetorum to be a junior synonym of T. ambiguus.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
03E5E90BFF812332FF3C9A25FD0D744D.taxon	distribution	This taxon is known to occur from eastern and central Canada south to New Jersey, the Great Lakes region, and the northern Great Plains in the United States.	en	Shattuck, Steve, Cover, Stefan (2016): Taxonomy of some little-understood North American ants (Hymenoptera: Formicidae). Zootaxa 4175 (1): 10-22, DOI: 10.11646/zootaxa.4175.1.2
