Summary

AimThis is the first comprehensive account of the biogeography of ants transferred and at least temporarily established outside their native habitat.



LocationUsing museum and literature records, I established the distributions of transferred ant species.



MethodsI used taxonomic and functional groups to assess how geographical spread as a transferred species is affected by taxonomy and life history.



Results147 ant species in forty-nine genera have been recorded outside of their native habitat. The proportion of transferred ants is similar to the number of genera and species in each subfamily. The species-rich subfamily Myrmicinae contains nearly 50% of all transferred species, while many of the species-poor subfamilies have absolutely no transferred species. A disproportionate high number of transferred ants originate from the Neotropical and Oriental biogeographic regions. The Pacific Islands are the recipients of the most transferred ant species. Most transferred ants belong to the CRYPTIC, OPPORTUNIST, and GENERALIZED MYRMICINE functional groups, while there are no recorded transfers of army ants or leaf-cutting ants. Both invasive and human commensal ‘tramp’ ant species are nonrandom subsets of transferred ants.



Main conclusions‘Tramp’ species and invasive species tend to have widespread geographical distributions, and share life history characteristics including queen number, nest structure, and foraging behaviour. Combining observations of functional groups and biogeography may lead to a better understanding of the factors contributing to the spread of transferred species.

The worldwide transfer of ants: geographical distribution and ecological invasions

Ant distribution and behavioural dominance is examined at nine sites along an elevational gradient (1400–2600 m) in south eastern Arizona, in order to classify North American species according to a functional group scheme used extensively in Australia. The functional groups are then used as a basis for determining patterns of community structure along the environmental gradient, and for comparing community structure between Australia and North America. Quantitative information on species com- position was obtained from pitfall traps, and patterns of ant abundance at tuna baits were used to determine relative behavioural dominance among taxa. A total of eighty-three species from twenty-eight genera was recorded along the elevational gradient, with site species richness ranging from four (high elevation Douglas fir forest) to thirty-three (mid elevation oak–juniper woodland). There was a strong correlation between ant abundance and richness, which was not an artefact of sampling intensity. The most common ants were species of Forelius, Monomorium, Crematogaster and Pheidole at the three desert sites, species of Formica, Pheidole and Crematogaster at the three woodland sites, and species of Prenolepis and Formica at one forest site. No species were abundant at two other forest sites. The most common species in traps also tended to be the most common species at baits. In terms of behavioural dominance, highly competitive ants included species of Solenopsis, Forelius, Monomorium and Liometopum. Species of Pheidole and Crematogaster tended to be moderately competitive, whereas species of Dory- myrmex, Myrmica, Camponotus and Formica (fusca gp) had low competitive ability. On the basis of these results and on published records of other taxa, North American ants were assigned to functional groups as follows (major taxa only given here): Dominant Dolichoderinae—Forelius, Liome- topum; Subordinate Camponotini—Camponotus; Hot Climate Specialists—Pogonomyrmex, Myrmecocystus; Cold Climate Specialists—Formica (rufa, exsecta and microgyna groups), Leptothorax, Stenamma, Lasius, Prenolepis; Cryptic Species—Smithistruma, Solenopsis (subgenus Diplorhop- trum), Acanthomyops; Opportunists—Formica (fusca group), Myrmica, Paratrechina, Dorymyrmex; Generalized Myr- micinae—Pheidole, Crematogaster, Monomorium; Specialist Predators—no major taxa. Functional group composition varied systematically along the elevation gradient: Dominant Dolichoderinae, Generalized MyrAmicinae and Hot Climate Specialists were predominant at desert sites; Generalized Myrmicinae and Opportunists were predominant at woodland sites; and Opportunists and Cold Climate Specialists were predominant at forest sites. These patterns are consistent with published studies from elsewhere in North America. Almost all North American taxa can be matched with what appear to be ecologically equivalent taxa in Australia, and biogeographic patterns of functional group composition are broadly similar across the two continents. The major differences are that Australian ant communities are far richer in species, and are almost always dominated by dolichoderines, particularly species of Iridomyrmex. Generalized myrmicines are subdominant to dolichoderines in Australia, but are the behaviourally dominant ants throughout the warmer parts of North America. In cool-temperate North America, species of Formica (especially rufa and exsecta groups) are behaviourally dominant, as they are throughout the Palearctic. Some major features of the North American fauna can be linked to its poor representation of Dominant Dolichoderinae, including (1) the relatively low degree of physiological, morphological and behavioural specialization of Hot Climate Specialists; (2) behavioural dominance by formicines in cool-temperate habitats; and (3) the susceptibility to invasion by behaviourally dominant species such as the imported fire ant Solenopsis invicta and the Argentine ant Linepithema humile.

Functional groups and patterns of organization in North American ant communities: a comparison with Australia

Evolution and biogeography of native Hawaiian Hylaeus bees (Hymenoptera: Colletidae)

Theory predicts that consumers selecting among complementary resources will show stronger preferences for items that become relatively less available. I tested this hypothesis in a field study that compared the preferences of ant colonies given simultaneous access to experimental foods differing in carbohydrate and protein content. In the first part of the study, I examined the effect of nutrient supplementation on colony-level preference in the ant Dorymyrmex smithi. Colonies that had received a protein solution for 24 h consumed proportionally more carbohydrates than control colonies that had been given access to water, suggesting that colonies preferred nutrients when they became relatively rare. In the second part of the study, I compared colony-level preference among eight species of ants that differ in their relative access to carbohydrates and protein in the field. I found that species with relatively easy access to carbohydrates preferred protein, whereas species with greater access to protein preferred carbohydrates. These results suggest that the benefits of a nutritionally mixed diet coupled with differences in the relative availability of nutrients may explain variation in feeding decisions both within and among ant species. Key words: ants, complementary resources, foraging theory, preference. [Behav Ecol 15:63–70 (2004)]

The relative availabilities of complementary resources affect the feeding preferences of ant colonies

The taxonomy and composition of the California ant fauna is reviewed, leading to the recognition of 281 species (in 44 genera), of which 255 are considered indigenous and 39 are endemic. Species-level endemism (13.9%) is higher than in adjacent regions, as is the percentage of non-native species (9.3%). About one quarter of the indigenous ant species are endemic to the California floristic province (sensu Hickman 1993). Approximately 36 species appear to be undescribed. Most of these undescribed species are assigned code names, which match those used on the “Ants of California” web site (http://www.antweb.org/california.jsp). One new species is described, Camponotus maritimus Ward, sp. nov., which corresponds to the taxon previously called Camponotus maculatus subsp. vicinus var. maritimus Wheeler (unavailable quadrinomen). Three species names are revalidated: Leptothorax calderoni Creighton stat. reval., stat. nov., Myrmica glacialis Emery stat. reval., stat. nov., and Temnothorax rudis (Wheeler) stat. reval., comb. nov. The following new synonymy is proposed (senior synonym listed first): Forelius pruinosus (Roger) = F. analis (Andre); Monomorium ergatogyna Wheeler = M. wheelerorum DuBois; Temnothorax andrei (Emery) = T. nitens heathii (Wheeler) = T. nitens occidentalis (Wheeler) = T. ocellatus (MacKay); Temnothorax nevadensis (Wheeler) = T. lindae (MacKay) = T. maryanae (MacKay); Temnothorax nitens (Emery) = T. mariposa (Wheeler) = T. melinus (MacKay). The genus Acanthomyops Mayr is demoted to subgenus (stat. rev.) within Lasius Fabricius, in accord with recent molecular phylogenetic results. A key to the ant genera of California (based on the worker caste), a synopsis of each genus, a comprehensive bibliography, and a species list are also provided. Keywords. ant taxonomy, distribution, biogeography, endemism, Camponotus, Lasius, Forelius, Monomorium, Myrmica, Leptothorax, Temnothorax Like other components of the California biota, the ant fauna of this state shows considerable biological diversity and regional endemism. Yet there has been no comprehensive systematic treatment of the ants of California, much less a reliable checklist or a set of identification keys. Part of this stems from the complexity of the fauna and an attendant rash of taxonomic problems whose resolution requires additional study at a larger geographical scale. In light of these constraints, the present paper aims to provide no more than a cursory survey of the ant genera, a provisional list of species, and a guide to the literature. A few necessary taxonomic changes are introduced, mostly involving new synonymy at the species level. A prime motivation for this paper stems from the need to establish a reference checklist for a new web site illustrating the ants of California (http:// www.antweb.org/california.jsp). This web site, developed in collaboration with Brian Fisher (California Academy of Sciences), is designed to facilitate identification by providing high-quality digital images of the known California ant species. The first descriptions of California ants appeared in the nineteenth and early twentieth century, in widely scattered taxonomic papers by Buckley, Emery, Forel, Mayr, W. M. Wheeler and others. Mallis (1941) and Cook (1953) published a species list and a booklength treatment, respectively, of the ants of California but both of these are out-of-date and error-ridden. Revisionary studies on specific groups of ants, carried out within the last 60 years and usually at a continent-wide scale, have had a more salutary effect on our knowledge of the California ant fauna. This includes taxonomic contributions by Bolton (1979), Brown (1950d, 1953g), Buren (1968b), Cole (1968), Creighton (1950a), Francoeur (1973), Gregg (1959, 1969b), Mackay (2000), Snelling (1970, 1973c, 1976, 1982a, 1982b, 1988, 1995a), Trager (1984b, 1991), Ward (1985b, 1999), Watkins (1976, 1985), Wilson (1955a, 2003) and Wing (1968a). Among the more useful publications for those seeking information about the ants of California are the regional treatments of the ants of Deep Canyon, Riverside County (Wheeler & Wheeler 1973e), the California deserts

/pdf/a-synoptic-review-of-the-ants-of-california-hymenoptera-4hvn6yr0ye.pdf

A synoptic review of the ants of California (Hymenoptera: Formicidae)

https://zenodo.org/record/24735/files/2728.pdf

Roy R. Snelling

Papers

A Revision of the Honey Ants, Genus Myrmecocystus, First Supplement (Hymenoptera: Formicidae)

Studies on North American Bees of the Genus Hylaeus. 3. The Nearctic Subgenera (Hymenoptera: Colletidae)

A Newly Adventive Ant of the Genus Pheidole in Southern California (Hymenoptera: Formicidae)

The Taxonomy of Some Neotropical Hylaeus and Descriptions of New Taxa (Hymenoptera: Colletidae)

Description of a New Subgenus of Osmia (Hymenoptera: Megachilidae)