An updated checklist of the ants of Thailand (Hymenoptera, Formicidae)

Reviewed by: Ban Chiang, Northeast Thailand, vol. 2C: The Metal Remains in Regional Context ed. by Joyce C. White and Elizabeth G. Hamilton Siân E. Halcrow and Nigel J. Chang Ban Chiang, Northeast Thailand, vol. 2C: The Metal Remains in Regional Context. Joyce C. White and Elizabeth G. Hamilton, eds. University Museum Monograph 153. Philadelphia: University of Pennsylvania Museum of Archaeology and Anthropology, 2020. 240 pp., 15 color, 29 b&w illustrations. Cloth US $70, ISBN 9781931707930. The third volume of the Thai Archaeology Monograph (TAM) Series on the metal remains at Ban Chiang provides important interpretations of the metal evidence within a regional social context. This edited volume presents substantive contributions from multiple scholars on copper mining and smelting from Thailand and Laos, provenance research on artifacts from the sites of Ban Chiang and Dan Klang, and a thorough regional synthesis of metal technology systems in Northeast and Central Thailand. This corpus of work presented by the authors supports the theory that there was a maintenance of regional economic networks with communit-based, nonhierarchical, social organization of production in these metal age societies. The introduction (chapter 1) by Joyce White succinctly describes the outcomes of this research showcasing a regional, culturally specific view of metal production, distribution, and consumption. Chapter 2 by Vincent Piggott reviews prehistoric copper mining and smelting in Southeast Asia using evidence from Thailand and Laos. This contribution provides a comprehensive review of the evidence for early copper mining and smelting in Northeast (Phu Lon complex in the greater Loei region) and Central (Khao Wong Prachan Valley) Thailand and Sepon in Lao [End Page 462] PDR. Given the extensive nature of these sites, it is concluded that they were the likely ore sources for these basins, if not for the entirety of Southeast Asia during the late second to first millennia b.c. Using the model suggested by Tucci and colleagues (2014) for the relationship between socio-political power and mining activity, Pigott argues that mining was conducted in these areas following the community-based consumption model within heterarchical contexts, although Sepon mining may have been influenced by dynastic China from as early as the Eastern Zhou Dynasty, throughout the Qin and Han dynasties, and into the remainder of the first millennium a.d. In chapter 3, T. O. Pryce presents sourcing data from copper-based artifacts from Ban Chiang and Don Klang. Here, provenance information concerning production and consumption is investigated through the geochemical characterization of the metals, using elemental compositional data and lead isotopic analyses for the regions and a range of archaeological artifact types. The results show that prehistoric sites obtained their metals from a number of different networks that are inconsistent with the Phu Lon production signature, as previously thought by White and Pigott (1996). These production and consumption network findings are nevertheless consistent with the proposed general model of riverine metal supply networks in the region (White and Pigott 1996). Sepon is the only identified source of copper used to produce the artifacts at Ban Chiang during its early period, perhaps as early as 1000 b.c. The results of further metalwork sourcing research (currently underway) will help tease out answers to questions about metal consumption across the region. In chapter 4, Elizabeth Hamilton and Joyce White provide an extensive compilation and synthesis of English language publications on metal production and consumption in prehistoric northern Northeast Thailand. This chapter fully contextualizes this work within the wider regional context of southern Northeast and Central Thailand to assess regional patterns of social growth and interaction. Metal analyses of artifacts from these excavations have revealed that, although the products are different between the Upper Mun River Valley and northern Northeast Thailand, there are similarities in the casting tradition. For example, the finds of lagged spouted crucible pieces and several metalworking hearths show that such final metal products were cast locally. Although there is little published literature on the topic of metalwork in Central Thailand, the reviewed data suggest there were variable forms and metal compositions, with copper appearing to be the focus of metal production in Central Thailand compared with tin bronze in Northeast Thailand throughout the sequence; the authors argue that this...

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 Emerystat. 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 (André); 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, TemnothoraxLike 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

Aim: Recent coarse‐scale studies have shown positive relationships between the biodiversity of plants/vertebrates and the human population. Little is known about the generality of the pattern for invertebrates. Moreover, biodiversity and human population might correlate because they both covary with other factors such as energy availability and habitat heterogeneity. Here we test these two non‐mutually exclusive mechanisms with ant species‐richness data from the Fauna Europaea.Location Forty‐three European countries/regions.Methods We derived mixed models of total, native and exotic ant species richness as a function of human population size/density, controlling for country area, plant species richness (as a proxy for habitat heterogeneity), and mean annual temperature and precipitation (variables related to energy availability).Results Ant species richness increased significantly with increasing human population. This result was confirmed when controlling for variations in country area. Both for human population size/density and for ant species richness, there were positive correlations with temperature but not with precipitation. This finding is in agreement with the energy‐availability hypothesis. However, we observed a negative latitudinal gradient in ant and plant species richness, although not in human population size/density. Plant species richness was positively correlated with ant species richness but not with human population size/density. Thus, there is evidence that this type of habitat heterogeneity can play a role in the observed latitudinal gradient of ant species richness, but not in the positive correlation between ant species richness and human population. The results were confirmed for the 545 native and the 32 exotic ant species reported, and we observed a good correlation between exotic and native ant species richness.Main conclusions Ant species richness in European countries conforms to six macroecological patterns: (1) a negative latitudinal gradient; and a positive (2) species–energy relationship, (3) species–area relationship, (4) correlation with plant species richness, (5) exotic–native species richness correlation, and (6) species–people correlation. There is some evidence for the energy‐availability hypothesis, but little evidence for habitat heterogeneity as an explanation of the large‐scale human population–ant biodiversity correlation. This correlation has implications for the conservation of ant diversity in Europe.

Sprawling development can affect species composition by increasing the rate of invasion by non-native species, and decreasing the persistence of native species. This paper briefly reviews the scientific literature on the impacts of sprawl on biological diversity, with specific emphasis on the influence of sprawl on non-native species richness. We then explore the relationship between sprawl and biodiversity using a data set of ant species collected from 46 habitat patches located in the increasingly suburbanized Florida Keys, USA. We quantified sprawl as the proximity of roads and amount of development surrounding a habitat patch. Using bait transects, we identified 24 native and 18 non-native species of ants. Neither the overall number of native species nor the number of rare native species were significantly affected by the amount of development or proximity to roads, however, the number of non-native species was significantly correlated with the amount of development. Surprisingly, the number of native species and rare native species was significantly positively correlated with the number of non-native species. Areas that supported many species of native ants also supported a diverse non-native ant fauna, and the species distribution was highly nested. Currently, the native ant fauna of the Florida Keys does not appear to be dramatically influenced by sprawl, however, if development increases, the number of non-native ants may increase, and many of these species have been documented as decreasing native ant diversity. If development plateaus, there is evidence that the native ant fauna could persist and could decrease non-native species richness through competition or predation.

Ants represent a highly diverse and ecologically important group of insects found in almost all terrestrial ecosystems. A subset of ant species have been widely transported around the globe and invade many natural ecosystems, often out-competing native counterparts and causing varying impacts on recipient ecosystems. Decisions to control non-native ant populations require an understanding of their interactions and related impacts on native communities. We employed stable isotope analysis and metabarcoding techniques to identify potential dietary niche overlap and identify gut contents of 10 ant species found in natural ecosystems in Aotearoa New Zealand. Additionally, we looked at co-occurrence to identify potential competitive interactions among native and non-native ant species. Ants fed mainly across two trophic levels, with high dietary overlap. Relative to other ant species sampled, two non-native ant species, Linepithema humile and Technomyrmex jocosus, were found to feed at the lowest trophic level. The largest isotopic niche overlap was observed between the native Monomorium antarcticum and the invasive Ochetellus glaber, with analyses revealing a negative co-occurrence pattern. Sequence data of ant gut content identified 51 molecular operational taxonomic units, representing 22 orders and 34 families, and primarily consisting of arthropod DNA. Although we generally found high dietary overlap among species, negative occurrence between a dominant, non-native species and a ubiquitous native species indicates that species-specific interactions could be negatively impacting native ecosystems. Our research progresses and informs the currently limited knowledge around establishing protocols for metabarcoding to investigate ant diet and interactions between native and non-native ant species.

AimTo examine the relationship between island characteristics (area, distance to the nearest continent, climate and human population size) and ant species richness, as well as the factors underlying global geographical clustering of native and exotic ant composition on islands.LocationOne hundred and two islands from 20 island groups around the world.MethodsWe used spatial linear models that consider the spatial structure of islands to examine patterns of ant species richness. We also performed modularity analyses to identify clusters of islands hosting a similar suite of species and constructed conditional inference trees to assess the characteristics of islands that explain the formation of these island–ant groups.ResultsIsland area was the best predictor of ant species richness. However, distance to the nearest continent was an important predictor of native ant species richness, as was human population size for exotic species richness. Native species appear slightly more modulated (i.e. well grouped in species assemblages that are present over a distinct cluster of islands) than are exotic species. Exotic species, while still exhibiting some modularity, tended to be widely distributed among island groups. Interestingly, ocean currents accounted for most of the variation in modularity and thus species composition for both native and exotic ant species.Main conclusionsContrary to previous work, both native and exotic species appeared to be confined to particular island regions, and patterns in the distribution of both native and exotic species were limited by a similar suite of factors. However, the distribution of exotic ant species appeared to be more influenced by human‐related variables and less structured relative to those of native ant species, perhaps due to the long‐term (and increasing) influence of human‐mediated dispersal that favours exotic species.

Understanding how land-use change affects biodiversity is a fundamental step to develop effective conservation strategies in human-modified tropical landscapes. Here, we analyzed how land-use change through tropical small-scale agriculture affects endemic, exotic, and non-endemic native ant communities, focusing on vanilla landscapes in north-eastern Madagascar, a global biodiversity hotspot. First, we compared ant species richness and species composition across seven land-use types: old-growth forest, forest fragment, forest-derived vanilla agroforest, fallow-derived vanilla agroforest, woody fallow, herbaceous fallow, and rice paddy. Second, we assessed how environmental factors drive ant species richness in the agricultural matrix to identify management options that promote endemic and non-endemic native while controlling exotic ant species. We found that old-growth forest, forest fragment, and forest-derived vanilla agroforest supported the highest endemic ant species richness. Exotic ant species richness, by contrast, was lowest in old-growth forest but highest in herbaceous fallows, woody fallows, and rice paddy. Rice paddy had the lowest non-endemic native ant species richness. Ant species composition differed among land-use types, highlighting the uniqueness of old-growth forest in harboring endemic ant species which are more sensitive to disturbance. In the agricultural matrix, higher canopy closure and landscape forest cover were associated with an increase of endemic ant species richness but a decrease of exotic ant species richness. We conclude that preserving remnant forest fragments and promoting vanilla agroforests with a greater canopy closure in the agricultural matrix are important management strategies to complement the role of old-growth forests for endemic ant conservation in north-eastern Madagascar.

AimsAnts (Hymenoptera: Formicidae) of the Baja California peninsula are poorly known, with information based largely on scattered museum and literature records. We provide the first comprehensive account of ant species occurring on the peninsula, we examine distribution patterns, and we assess the ‘peninsular effect’ which predicts that species richness declines from the base to the tip of a peninsula.LocationPeninsula of Baja California, Mexico.MethodsData collection involved examining, identifying and recording label data fromc.2350 series of ants. These records provide a provisional, if incomplete, species list. We applied the incidence‐based estimator, Chao‐2, to our data base of specimen records to estimate the total number of ant species on the peninsula. We assessed endemism by comparing our peninsular species list to those from adjacent states. The peninsular effect was tested by comparing genus and species level richness between the two states of Baja California, and across five latitudinal blocks.ResultsWe document 170 native ant species in thirty‐three genera, plus six non‐native species, in Baja California. It seems likely that additional species remain to be discovered: the Chao‐2 estimator of species richness, at 206.0 species, is about 20% higher than our observed species richness. About 30% of the species and 20% of the genera are restricted within Baja California to the relatively mesic California Floristic Province of north‐western Baja California. Nearly all of these species also occur in California. Forty‐seven species (27.6%) are peninsula endemics. Using our entire data set, the peninsular effect appears to be strong, with about twice as many species in the northern state of Baja California than are recorded from the southern state of Baja California Sur; the ratio of genera is 33 to 24. However, this effect becomes weak at the species level and absent at the genus level when minimizing habitat effects by omitting species restricted to the California Floristic Province. At a finer scale, across latitudinal blocks of about 1.9°, the number of species declines towards central portions of the peninsula and then increases in the Cape Region. Nine ant species display strongly disjunct distributions, and these occur in two general patterns: peninsula disjuncts and peninsula–mainland disjuncts.Main conclusionsThe Baja California peninsula supports a diverse and distinctive ant fauna, with the proportion of endemic species similar to that displayed by plants. Patterns of species and genus richness across the five latitudinal blocks provide poor support for the peninsular effect. Moreover, habitat diversity, especially that related to topographic relief, appears to be the most important factor affecting the gradient of ant species richness in Baja California. Additional collections are needed to develop a more complete species list and to determine the boundaries and status of many species. Nevertheless, the present data base provides a useful starting point for understanding the evolution of ant assemblages in Baja California and for comparison with peninsular patterns in other taxa.

The role of ecotones in the maintenance of species diversity is rather controversial; they may represent either biodiversity hotspots with unique and rare forms, or be transitional areas that hold marginal populations of species. We analyse the taxonomic and functional composition of ant species assemblages across the Subantarctic-Patagonian transition to evaluate the role that transitional shrublands may play in the maintenance of the taxonomic and functional differentiation. We collected ants using 450 pitfall traps within a ~150 × 150 km area. Species were classified into functional groups in relation to stress and disturbance, and in foraging groups according to their foraging behavior. An indicator value for each species in each habitat was calculated. The steppes and the forests strongly differed in ant species and functional composition. Climatic effects combined with structural components of plant environment explained about 23–27 % of the variation in ant composition. The shrublands did not show a distinctive fauna, and show greater similarity in ant species composition and in the proportional occupancy of functional groups to the steppes than to the forests. They harbor neither rare nor indicator species, except for Lasiophanes valdiviensis, and thus this reinforces the idea that they are not a habitat source of species, but an area of encounter between two distinct forest- and steppe- ant faunas, where a high number of local distributional limits of ant species overlap.

Red mangroves (Rhizophora mangle) grow in and adjacent to shallow brackish water in subtropical and tropical estuaries around the world, and provide a unique arboreal habitat, often completely isolated by water from any terrestrial habitat. I collected ants nesting inside the hollow dead twigs, small branches, air roots, and prop roots of red mangroves at 98 sites in 9 counties along the east coast of Florida, from Volusia County in the north to the Upper Keys of Monroe County in the south. I found a total of 22 ant species nesting in red mangroves, including ten native species, eight exotic species (four Old World, four New World), and four New World species whose status in Florida is uncertain. The most common species by far were two native species (Tapinoma litorale and Xenomyrmex floridanus). The next three most common species, however, were exotics (Monomorium floricola, Pseudomyrmex gracilis, and Technomyrmex difficilis). I also collected the first Florida specimens of Crematogaster steinheili, a species that is very common in red mangroves of the West Indies, but may be exotic to Florida. Several native and exotic species show strikingly similar ecologies. For example, native X. floridanus and exotic M. floricola are both tiny, thin, short-legged, slowmoving myrmicine ants that cling tenaciously to surfaces. Earlier studies indicate that native ant species compete for resources in red mangroves. It seems likely that exotic ant species in the red mangroves also compete with and may threaten the native ant species.

Abstract. Within the framework of a fisheries project in north-east Thailand, project MK/FSPC/069 entitled ‘The Fish Seed Production Centre, North East Thailand’, an assessment was carried out of the ecological impact of introducing exotic fish species (common carp, Cyprinus carpio L., Nile tilapia, Oreochromis niloticus (L.), and Chinese and Indian carps). For the assessment, the protocol of Kohler & Stanley (1984) was followed, covering feasibility of introduction, acclimatization potential, potential impact, and control potentials. Regarding the (ongoing) use of the proposed exotic species in aquaculture, it was concluded that so far no clear ecological impact has been reported from escapes to open water; the use of the exotic species has shown to be highly beneficial from a 9 socio-economic point of view. Regarding the proposed introduction of the exotic species into public waters (natural lakes and man-made reservoirs), it was concluded that earlier releases of these species in north-east Thailand did not provoke severe ecological impact in terms of deterioration of aquatic ecosystems. Incidental cases of minor ecological impact were reported for common carp and nile tilapia. Indications were obtained for niche competition between Chinese and Indian carps and indigenous carps, while similar niche competition was concluded for bighead carp, Aristichthys nobilis (Richardson), and indigenous pelagic zooplankton feeders. Observing the prolific development of the Nile tilapia in a number of reported cases, it was recommended not to include this species in stocking programmes for public water bodies, until more risk assessments are available.

Inland Australia supports by far the world's most diverse arid-adapted ant fauna, but there are no published studies of regional ant faunas from the central arid zone. Here we describe the ants collected by pitfall trapping at 22 sites in World Heritage-listed Uluru-Kata Tjuta National Park (300 mm mean annual rainfall), representing all major vegetation types from spinifex grasslands to eucalypt woodlands. A total of 154 (mostly undescribed) ant species from 26 genera were recorded, with the richest genera being Melophorus (30 species), Monomorium (26), Iridomyrmex (18) and Camponotus (12). The pattern of species accumulation suggests that many more species remain to be collected from the Park, and we estimate that the total fauna consists of around 300 species. The most abundant ants were species of Iridomyrmex (collectively contributing 76% of all ants collected), as is the case throughout arid Australia. Species of Monomorium and Melophorus were also highly abundant. No exotic species were recorded. Ant species composition was strongly related to vegetation type, with a particular distinction between the various grasslands on one hand, and woodlands on the other. Unexpectedly, species richness was higher in structurally simple spinifex grasslands than in eucalypt woodlands. The woodland fauna lacks many taxa characteristic of such habitats in similarly arid regions of southern Australia, which we attribute to remoteness and small patch size. Uluru-Kata Tjuta National Park supports an extremely diverse ant fauna, but surveys of other areas are required for an improved understanding of patterns of ant biodiversity in Australia's central arid zone.

Ehrlichia canis and Anaplasma platys are tick-borne, Gram-negative bacteria that cause canine monocytic ehrlichiosis and canine cyclic thrombocytopenia, respectively. These diseases are of great importance and are distributed globally. This study aimed to create new primers for the identification of E. canis and A. platys in naturally infected dogs using polymerase chain reaction (PCR), DNA sequencing, and phylogenetic analysis using the 16S rDNA and gltA genes. In total, 120 blood samples were collected from dogs in three different locations (Saraburi, Buriram, and Nakhon Ratchasima provinces) in Central and Northeast Thailand. The molecular prevalence of E. canis and A. platys was assessed using PCR targeting the 16S rDNA and gltA genes. All positive PCR amplicons were sequenced, and phylogenetic trees were constructed based on the maximum likelihood method. Ehrlichia canis had an overall molecular prevalence of 15.8% based on the 16S rDNA gene, compared to 8.3% based on the gltA gene. In addition, the overall molecular prevalence of A. platys using the 16S rDNA gene was 10.8%, while the prevalence rate was 5.8% using the gltA gene. Coinfection was 0.8% in Saraburi province. The partial sequences of the 16S rDNA and gltA genes of E. canis and A. platys in dogs in Central and Northeast Thailand showed 96.75%-100% identity to reference sequences in GenBank. Phylogenetic analysis of the 16S rDNA and gltA genes revealed that E. canis and A. platys sequences were clearly grouped into their own clades. This study demonstrated the molecular prevalence of E. canis and A. platys in Central and Northeast Thailand. The 16S rDNA and gltA genes were useful for the diagnosis of E. canis and A. platys. Based on the phylogenetic analysis, the partial sequences of the 16S rDNA and gltA genes in E. canis and A. platys were related to prior Thai strains and those from other countries.

Reduced biodiversity and high number of endemics characterize island ecosystems. Island natives and endemics are considered more vulnerable than continental species to exotic species invasions and habitat changes. The effect of replacing a native forest by an exotic wood plantation was studied on the assemblage of native and endemic ant species. The main hypothesis was that endemic and native ant species were more vulnerable to habitat changes than the exotic ant species. Nevertheless, it was found that native ants were more numerous and specious in both native and exotic plantations. Also, high numbers of two endemic ants were detected within exotic plantations, while only one exotic ant Hypoponera opacipeps was relatively abundant, particularly on native forest. In conclusion, exotic ant species did not dominate the communities studied nor the native and endemic ant assemblages seemed to be affected negatively by the forest replacement.

Infections with feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) occur worldwide and are among the most important infectious diseases in cats. The aim of the present study was to determine the prevalence of FIV and FeLV infection in healthy outdoor cats in North, Northeast and Central Thailand. So far, a study on retrovirus prevalence of healthy cats in Thailand in a larger geographic area has not been published yet. In addition, risk factors for FIV and FeLV infections were evaluated. Two hundred sixty healthy cats were prospectively recruited. They originated from 13 locations in North, Northeast, and Central Thailand and were presented for either preventive health care and/or neutering. In each cat, a physical examination was performed to confirm health status. FIV and FeLV status was determined using a commercial rapid enzyme-linked immunosorbent assay (ELISA) (SNAP Combo Plus FeLV/FIV, IDEXX). Risk factors were analyzed by binary logistic regression analysis. Samples of 15/260 (5.8%) cats were positive for FIV antibodies, and 11/260 (4.2%) samples were positive for FeLV antigen. One of the 260 (0.4%) cats was positive for both, FIV and FeLV infection. In binary logistic regression analysis, no parameter was associated with a higher risk for FeLV infection. However, cats had a significantly (p = 0.025) higher risk for FIV infection when they were 2 years or older. FIV and FeLV infections occur in healthy cats in North, Northeast and Central Thailand, but prevalence was lower than expected. No risk factors for FeLV infection were detected, but risk for FIV infection increases with age.