Open access journal: http://periodicos.uefs.br/ojs/index.php/sociobiology ISSN: 0361-6525 DOI: 10.13102/sociobiology.v61i1.9-20Sociobiology 61(1): 9-20 (March, 2014) Composition and Diversity of Ant Species into Leaf Litter of Two Fragments of a Semi- Deciduous Seasonal Forest in the Atlantic Forest Biome in Barra do Choça, Bahia, Brazil Freitas, JMS1,2,3, Delabie, JHC1,2 & Lacau, S1,2,3 Introduction Ants (Hymenoptera: Formicidae) form one of the most diverse and ecologically important insect groups in terms of their diverse and essential functions in terrestrial ecosystems (Wilson & Hölldobler, 1990; Alonso & Agosti, 2000). Their predominance can be attributed in part to their eusocial nature, which favors their dispersal and successful occupation of new habitats (Wilson & Hölldobler, 2005). Since the Cretaceous period, these animals have demonstrated successful radiation throughout almost all terrestrial habitats, with numerical and biomass predominance in most of them (Fernández & Ospina, 2003; Wilson & Hölldobler, 2005). Ant diversity in forest ecosystems is particularly high in the leaf litter (Alonso & Agosti, 2000; Silva & Brandão, 2010), although community composition is influenced by nu- merous factors, including the nature of the surrounding plant formations, soil composition and the local microclimate Abstract We present here the results of a study of leaf litter ant diversity in remnant areas of semi-deciduous seasonal forests in the Atlantic Forest biome. Standardized collections were made in 2011, using pitfall traps and Winkler sacks in two fragments of native forest in the municipality of Barra do Choça in the micro-region of the Planalto da Conquista, in southwestern of the state of Bahia, Brazil. A total of 107 species from 37 ant genera and 9 subfamilies was collected. The observed richness was high, and the diversity indices (Shannon-Wiener) of the two fragments suggest that in spite of being strongly impacted by anthropogenic actions, they maintained high faunal diversity levels, similar to those observed in other original Atlantic Forest sites in state of Bahia. Analyses of the spe- cies accumulation curves (Jackknife 2), however, indicated that survey effort was not sufficient to capture all of the species present. The high observed numbers of unique species, the shape of the species accumulation curves, and high values of estimated richness suggest that the survey areas were quite heterogeneous. These results provide new information concerning regional biodiversity that will be useful for continuing studies on fragmentation processes in the region. Sociobiology An international journal on social insects 1 - Universidade Estadual de Santa Cruz, Ilhéus-BA, Brazil. 2 - Laboratório de Mirmecologia, CEPLAC/CEPEC/SECEN, Ilhéus-BA, Brazil. 3 - Universidade Estadual do Sudoeste da Bahia, Itapetinga-BA, Brazil. Article History Edited by: Gilberto M M Santos, UEFS, Brazil Received 05 November 2013 Initial acceptance 13 December 2013 Final acceptance 14 January 2014 Keywords Formicidae, Planalto da Conquista, Atlantic Forest, Tropical forest Corresponding author Juliana Martins da Silva Freitas Univ. Estadual do Sudoeste da Bahia Laboratório de Biossistemática Animal Itapetinga-BA, Brazil E-mail:julliana.martins@yahoo.com.br (Schowalter & Sabin, 1991). Ant community structures re- spond directly and quickly to both quantitative and qualita- tive environmental changes, and have therefore been the focus of stu-dies investigating the effects of environmental distur- bances on ecological communities (Veiga-Ferreira et al., 2005; Delabie et al., 2006, 2007). Ants maintain numerous biotic associations with other organisms in their environments (Wilson & Hölldobler, 1990; Rico-Gray & Oliveira, 2007), rapidly respond to habitat alter- ations such as fragmentation (Peck et al., 1998; Veiga-Ferreira et al., 2005; Delabie et al., 2006) and are relatively easily col- lected and identified (Peck et al., 1998), making them ideal models for studying and monitoring global biodiversity and useful as bioindicators of disturbances caused by ecosystem size reductions The Atlantic Forest biome has been a focal area for environmental conservation efforts (Dean, 2002). Studies of Atlantic Forest biodiversity have almost exclusively fo- RESEARCH ARTICLE - ANTS Freitas, JMS, Delabie, JHC & Lacau, S. - Leaf-litter Ant Communities in Bahia Atlantic Forest, Brazil 10 cused on ombrophilous forests on the coastal plains of Brazil (Ivanauskas & Rodrigues, 2000; Costa & Mantovani, 1993; Martins, 1993). However, a number of diverse ecosystems are found in this biome (Brasil, 2000), including semi-deciduous and deciduous seasonal forests in the region of southwestern of the state of Bahia, and some have been poorly studied (es- pecially those situated more inland) (Brasil, 2000). The semi- deciduous seasonal forest exhibits high biodiversity due to the confluence between Atlantic Forest, Caatinga (dryland vegeta- tion), and Cerrado (Neotropical savanna) biomes (Soares- Filho, 2000; Daniel & Arruda, 2005; Dean, 2002). They are highly threatened and have experienced critical levels of fragmentation due to agricultural expansion, pasture forma- tion, and urban occupation, among other factors (Campanili & Prochnow, 2006). One of the most highly neglected regions in terms of studies of ant fauna diversity is the Atlantic Forest in the southwestern region of the state of Bahia, principally the Planalto da Conquista. These vegetation formations are con- sidered “Inland Atlantic Forests of Bahia” (classified as semi- deciduous seasonal forests) The present study was designed to examine the ant fauna of this region and characterize the composition and diversity of ant species in the leaf litter of two remnant forest fragments situated in the municipality of Barra do Choça, in the Planalto da Conquista, state of Bahia State, Brazil. Materials and Methods Collection sites The surveys were performed in two areas of Semi- Deciduous Seasonal Forest: “Remnant 1” (14°50’00”S 40°33’13”W; 86 hectares) and “Remnant 2” (14°48’29”S 40°35’23”W; 62 hectares) (Fig. 1). Both fragments were lo- cated in the municipality of Barra do Choça, in the state of Bahia, Brazil, within the transition zone between dense om- brophilous forests and seasonal deciduous forest areas (IBGE, 1993; 1997) in formations locally known as “mata de cipó” (Soares-Filho, 2000) ; between 20 and 50% of the trees there are large deciduous species (IBGE, 1993; 1997; Soares-Filho, 2000). These once extensive native forest formations are cur- rently represented only by remnant fragments that have expe- rienced intense processes of environmental degradation from agro-pastoral activities and the selective extraction of com- mercially valuable trees (Soares-Filho, 2000; Projeto Mata Atlântica Interiorana da Bahia, 2002; Oliveira-Filho et al., 1994). The fragments studied here are embedded within monoculture and pasture matrices, and their interiors demonstrate clear evidence of selective cutting and cattle trails. The regional climate is classified as high-elevation tropical (IBGE, 1993; 1997), with a mean annual temperature of 19.8 ºC, and a mean annual rainfall rate of 734 mm. Collection methodology Ant collections were made in January and April/2011 using 47 Winkler sacks and 47 pitfall traps (Bestelmeyer et al., 2000) in each fragment (one Winkler sack was destroyed in fragment 1, Table 1) distributed at intervals of 30 m within an area of approximately 10 hectares – but always at least 100 m from the external edges of the fragment. A pitfall trap was installed at each collection point and left for two days. These traps consisted of cups of 7 cm diameter by 10 cm height con- taining only water and detergent. When the pitfall trap was re- moved, an additional sample of 1 m² of leaf litter was removed from the same site, passed through a sieve, and then processed in a Winkler extractor for 48 hours (Bestelmeyer et al., 2000). This standardized methodology was adapted from the Ants of the Leaf Litter Protocol of Agosti & Alonso (2001). Biological material The biological material collected in the field was pre- served in ethanol and then taken to the Laboratório de Mirme- cologia (CEPLAC/CEPEC/SECEN) and Laboratório de Biossistemática Animal (UESB/DEBI) where ant specimens were sorted out from the samples, mounted and identified to species level. The nomenclature follows Bolton et al. (2011) and Wilson (2003). Representative materials of all of the spe- cies are deposited in the Myrmecology Laboratory Collection (CPDC) under the reference number #5729. Data analyses Data was recorded using Excel version 10 software (Microsoft, 2007) which was used to calculate the relative frequencies of the species and their species richness for each different area and for each type of trap. EstimateS software version 8.2 (Colwell, 1997) was used to generate species accumulation curves for each area and each type of trap in terms of the sampling effort employed (Santos, 2003). The Fig 1 - Satellite picture of the two forest remnant where the experi- ment was conducted. Barra do Choça, Bahia, Brazil (Source: Google Earth, 2011). Sociobiology 61(1): 9-20 (March, 2014) 11 estimated species richness was subsequently calculated for each area using the Jackknife 2 index – an index based on the numbers of species that occur only once in a sample (single- tons) and those occurring twice (doubletons). To determine if there were significant differences between the occurrences of ant species between the different fragments and between the different types of traps utilized, two-way analyses of variance (ANOVA Factorial) were performed using PRIMER 5 software (Clarke & Gorley 2001). The Shannon-Wiener diversity index was used to calculate the alpha diversity of the two fragments using Bioestat 5.3 software (Ayres, 2011). This index was chosen as it gives the same weight to both rare and abundant species. The t test was used to determine if there were signifi- cant differences between the diversity index values (also using Bioestat 5.3 software). Results and Discussion Observed richness A synoptic list of the species collected in the present study, and their occurrences as a function of the collection areas and types of trap utilized, is presented in the Appendix. A total of 107 ant species belonging to 36 genera and 9 sub- families were observed, with 83 species found in fragment 1, and 67 in fragment 2 (Table 1). These results indicated that the fragments analyzed retained relatively high faunal rich- nesses – even greater than reports for other areas of semi- deciduous forests in the Atlantic Forest biome (Mentoni et al., 2011; Dias et al., 2008, Castillho et al., 2011). The only other study that has examined ant diversity in remnant seasonal semi-deciduous forests in the region around the Planalto da Conquista was undertaken in 2011 by Sofia Campiolo, Ivan Nascimento, and Jacques Delabie (personal communication, May 4, 2011). These investigators under- took collections during the dry season using Winkler sacks in five areas relatively close to the present research site (in the municipalities of Barra do Choça, Itambé, and Vitória da Conquista). Their collection efforts were very similar to those of the present study, and they found between 47 and 86 species belonging to between 23 and 33 genera in the five fragments examined – results that are reasonably close to those of the present study (Table 1). In both types of trap, fragment 1 demonstrated greater taxonomic richness than fragment 2 in terms of the species, genus, and subfamily levels. This result is somewhat surpris- ing, as this fragment was 28% smaller than the other. In simi- lar studies, and in accordance with the theory of island bioge- ography (MacArthur and Wilson, 1967), positive correlations have been found between species richness and fragment sizes (Morini et al., 2007). One explanation for the observed dis- crepancy reported here could be that, in spite of the fact that the two fragments appeared to be phytosociologically simi- lar (Avaldo de Oliveira Soares Filho, personal communica- tion, January 10, 2011), the first fragment had more ecologi- cal niches available for ants. As such, and to better interpret the results, it would be interesting to quantify other diverse parameters in these forests fragments in future studies, such as the richness and diversity of their vegetation, their spatial structuring in terms of microhabitats, and available trophic resources. Table 1 - Summary of the results found in two forest remnants at Barra do Choça, Bahia, Brazil. W: Winkler sack, P: pitfall trap. Remnant 1 Remnant 2 W P W P Number of samples 46 47 47 47 Number of species occurrences 349 201 382 231 Number of subfamilies 9 7 7 7 Number of genus 31 28 22 22 Number of species 66 54 50 44 Number of estimated species (Jackknife2) 109.6 94.9 66.6 73.3 Singletons 25 26 11 19 Doubletons 5 10 5 8 Shannon-Wiener 3.68 3.44 3.45 3.05 Table 2 – Variations fonts of ANOVA test (two-way analyzes of variance - Factorial ANOVA) for comparisons of samples collected in two forest remnants at Barra do Choça, Bahia, Brazil. SS Degree of Freedom MS F p Intercept 6287.75 1 6287.75 140.653 0 Place/trap 209.446 1 209.446 4.6852 0.03156 Remnant 191.356 1 191.356 4.2805 0.03978 Remnant/trap 7.813 1 7.813 0.1748 0.67634 Error 9343.16 209 44.704 Freitas, JMS, Delabie, JHC & Lacau, S. - Leaf-litter Ant Communities in Bahia Atlantic Forest, Brazil 12 Winkler sacks collected larger numbers of species in both fragments than did pitfall traps (Table 1), although these differences were not statistically significant (F = 4.69 and P = 0.032, Table 2). Most published studies have shown that Winkler sacks can collect greater numbers of species than most other techniques (Sabu et al., 2011; Vargas et al., 2009), although this assertion was recently challenged by Souza et al., (2012) to the profit of pitfall traps. Nevertheless, both techniques complement each other for maximum sampling efficiency (Delabie et al., 2000). Winkler sacks are most effi- cient for collecting smaller species with cryptic behavior and low activity levels (Agosti et al, 2000), while pitfall traps are better for collecting large, active foraging ants that are not easily collected through Winkler method, such as species of the genera Camponotus, Pachycondyla or Odontomachus. Winkler sacks also harvested higher mean numbers of species per sampling point than pitfall traps (Table 3). These results are similar to those previously reported for native fo- rest sites in the Atlantic Forest biome (Marinho et al., 2002; Suguituru et al., 2013). It is worth noting that there were dif- ferences between the two fragments studied here in terms of their mean species richness per sampling point, with this value being lower in fragment 2 (although these differences were not statistically significant) (Table 3). Table 3 -Mean number of ant species (mean occurrence) observed in forest remnants in Barra do Choça, Bahia, Brazil. Values in the main diagonal of the matrix are means ± 1 SE. Differences between the pairs of ant species are based on Fisher post-hocTest. ns = not sig- nificant; * = P< 0.05; MW1 = species collected with Winkler sacks in first forest remnant; MW2 = species collected with Winkler sacks in second forest remnant; MP1 = species collected with pitfall traps in first forest remnant; MP2 = species collected with pitfall traps in second forest remnant; MW MW MP MP 1 2 1 2 MW 1 5.33±0.76 NS NS NS MW 2 7.64±1.13 * NS MP 1 3.72±0.65 NS MP 2 5.25±1.18 Richness estimates Richness accumulation curves for each type of trap for each area are shown in fig 2A and 2B. Analyses of the accu- mulated richness curves indicated complete sampling of the ant fauna was not achieved in either type of trap, as none of the curves approached the asymptote. Thus, projected rich- ness values were always greater than observed values (Table 1), which is the usual situation in biodiversity studies in the tropics (Martins & Santos, 1999; Feitosa & Ribeiro, 2005; Baccaro et al., 2011; Braga et al., 2010; Leponce et al., 2004; Delabie et al., 2007), since many rare species continue to be encountered even after extremely intense sampling efforts (Santos, 2003). The high estimated richness values could be explained by the study areas possibly having heterogeneous species dis- tributions, because, according to Chao (1987), the greater the heterogeneity of the species’ spatial distributions, the greater will be the observed divergences between observed and ex- pected richness. The large number of unique species encountered (Table 1) corroborated the results of the observed richness curves and diversity estimators. Unique species may be present in the area only as foragers (“tourist” species, according to Belshaw & Bolton, 1993), as rare species, as generalist species occa- sionally feeding in the locality, or as specialist that feed ex- clusively on plants occurring only in a single site in the study area. Also, the surveys may have been undertaken using inad- equate methodologies (particularly an issue with small popu- lations) (Novotny & Basset, 2000). The proportions of unique species in the present work were always greater than 30% of the total numbers of species collected – reaching up to almost 50% in the case of pitfall traps in the first fragment. Such high proportions of unique species are consistent with other biodi- versity studies of arthropods in tropical regions (Coddington et al., 2009) and with other ant studies undertaken in Atlantic Forest areas (Pacheco et al., 2009). Fig 2 - Species accumulation curves for ant species collected in Winkler sacks (A) and pitfall traps (B) in two forest remnant in Barra do Choça, Bahia, Brazil. MW1: first forest remnant, MW2: second forest remnant, MP1: first forest remnant, MP2: second forest remnant, S: observed richness, Jack 2: richness index estimated by Jackknife 2. Sociobiology 61(1): 9-20 (March, 2014) 13 Analyses of faunal composition The richest subfamilies at the species level in fragment 1 were: Myrmicinae (59% of the total number of species), For- micinae (15.7%), and Ponerinae (13.3%). The same tendency was observed at the genus level: Myrmicinae (52.6% of the total number of genera), Formicinae (13.2%), and Ponerinae (10.5%) (Appendix). The richest subfamilies at the species level in fragment 2 were: Myrmicinae (58% of the total num- ber of species encountered), Ponerinae (14.5%), and Formici- nae (14.5%), while at the generic level, the richest subfamilies were: Myrmicinae (44.4% of all of the genera encountered), Formicinae (18.5%), and Ponerinae (11.1%) (Appendix). The observation that the subfamily Myrmicinae was the richest in both fragments at both the genus and species levels, while the subfamilies Formicinae and Ponerinae demonstrated similar species richness, had been reported in other surveys of forested areas in the Neotropical region (Miranda et al., 2012). A particularly interesting find in fragment 1 was the capture of two specimens of Ochetomyrmex (Ochetomyrmex sp_LBSA_14010266) (very similar to Ochetomyrmex semi- politus but possibly distinct) – a new record for this genus in the state of Bahia, and extending the geographical distribution of this species by more than 2,380 km to the east (referring to the map given by Fernandez, 2003). A new species of Oxye- poecus Santschi, 1923 was also encountered (six specimens in fragment 2), which is now being described (Sebastien Lacau, personal communication, June 4, 2012). Another important collection was the capture of three specimens of Monomorium delabiei Fernandez, 2007 in fragment 2 – a species up to now only known from the holotype, described from Guaratinga, Bahia, Brazil (Fernandez, 2007). Differences existed in the composition of the species encountered in the two study areas, with only 38% of the spe- cies common to both areas – indicating considerable differences in the compositions of their respective species communities (Appendix). There was also a relationship between the global richness of each remnant at the species level and its degree of exclusivity, with fragment 1 being the most species rich (83 species) and having the most exclusive faunal composition (with 50.6% of the species and 36.8% of the genera being ex- clusive to that fragment), while fragment site 2 was the least rich (67 species) and had the least exclusive faunal composi- tion (with 34.3% of the species and 7.6% of the genera being exclusive to that fragment). Relative frequency and dominance To determine if the ant communities are organized into defined structural patterns, we examined the species relative frequencies in the two areas according to the types of traps in which they were caught. In the case of Winkler sacks, it was observed that 10 species were responsible for half of the oc- currences in fragment 1 (fig 3A), and eight species for half of the occurrences in fragment 2 (fig 3B). Four of those species (Hypoponera sp. 3, Nylanderia sp. 2, Gnamptogenys striatula and Solenopsis sp. 6) only were common to both areas. In the case of the pitfall traps, eight species were responsible for half of the occurrences in fragment 1 (fig 3C) and five species in fragment 2 (fig 3D), with three species (Pheidole radosz- kowskii, Gnamptogenys striatula, and Nylanderia sp. 2) being encountered in both fragments. The overall results demonstrated that the three most frequent species (Hypoponera sp. 3, Octostruma sp. 1, and Strumigenys sp. 4) were exclusively collected with Winkler sacks, suggesting that they have cryptic lifestyles, and nest and forage below the leaf litter surface. The same types of frequency analyses were performed to determine the identities and relative frequencies of the ge- nera responsible for 50% of the total occurrences in the collec- tions. In the case of the Winkler sacks, five genera (Pheidole, Solenopsis, Hypoponera, Nylanderia, and Strumigenys) were responsible for 50% of the occurrences in fragment 1 (fig 4A), while four genera (Solenopsis, Hypoponera, Nylanderia and Pheidole) were responsible for this same percentage in frag- ment 2 (fig 4B). Four genera (Pheidole, Solenopsis, Hypoponera, and Nylanderia) were encountered in both areas. In the case of the pitfall traps, three genera (Pheidole, Gnamptogenys, and Ectatomma) were found to be responsible for 50% of the occurrences in fragment 1 (fig 4C), and four genera in fragment 2 (Pheidole, Pachycondyla, Linepithema, and Solenopsis) (fig 4D). Only one genus (Pheidole) was en- countered in both fragments. These results emphasize the notable dominance of the genera Pheidole, Solenopsis, and Nylanderia. The genus Pheidole has been observed to be the most dominant in many studies of ant diversity, with two of its species consistently appearing among the most abundant arthropod representa- tives in the leaf litter. Pheidole is the most diversified genus in the family Formicidae (Wilson, 2003) and its species are encountered in all soil microhabitats, have wide ranges of feeding habits (most are omnivores), and demonstrate great effi- ciency in recruiting workers to exploit many trophic resources (Fernández, 2003). Some Pheidole species are rather aggres- sive in their relationships with competitors, are opportunists and can colonize a wide diversity of environments (Wilson, 2003). The observed dominance of this genus in the present study therefore corroborates the recognition of this genus as the most abundant and diversified in the Neotropical region (Majer & Delabie, 1994; Marinho, et al. 2002; Vasconcelos, 1999). In the same sense, the high abundance of Solenopsis species observed in the present study confirms previous ob- servations in the literature. Some species of this genus are common throughout the world (Fernandéz, 2003), principally in the leaf litter, with many of them being generalists in terms of their habitats and diets (Fowler et al., 1991). These species Freitas, JMS, Delabie, JHC & Lacau, S. - Leaf-litter Ant Communities in Bahia Atlantic Forest, Brazil 14 Fig 3 - Relative frequency of the species more collected in two forest remnant at Barra do Choça, Bahia, Brazil. (A) Samples collected with Winkler sacks in the first forest remnant; (B) Samples collected with Winkler sacks in the second forest remnant; (C) Samples collected with pitfall traps in the first forest remnant; (D) Samples collected with pitfall traps in the second forest remnant; Fig 4 - Relative frequency of the most frequently collected genera in two forest remnants at Barra do Choça, Bahia, Brazil. (A) Samples collected with Winkler sacks in the first forest remnant; (B) Samples collected with Winkler sacks in the second forest remnant; (C) Samples collected with pitfall traps in the first forest remnant; (D) Samples collected with pitfall traps in the second forest remnant. Sociobiology 61(1): 9-20 (March, 2014) 15 are also encountered with relatively high frequencies in agri- cultural areas (Dias et al., 2008). The genus Nylanderia was also very frequent in the present study, and previous publications have shown that the relatively small individuals that are characteristic of this ge- nus are quite abundant (Mentone, 2011), being terricolous or arborous, or occupying the leaf litter, in both natural and dis- turbed environments (Fernández, 2003). Diversity indices The alpha diversity estimates for the fragments, as cal- culated by the Shannon and Wiener index, can be found in Table 1 and are comparable to other biodiversity studies of ants in the Neotropical region (Lopes et al., 2010; Lutinski et al., 2008). The greatest alpha diversity was observed in frag- ment 1, corroborating the hypothesis that fragment 1 had the best phytosociological quality and favored the occurrence of a wider diversity of species. The situation in fragment 2 ap- parently represents a simplification of the original community structure. The differences between fragments were not, how- ever, statistically significant (t = 1.3291; P = 0.1576). Concluding comments The results obtained in the present study are totally original, and no similar research has previously been under- taken in the Planalto da Conquista region. It was observed that while the two fragments analyzed had both been subjected to anthropogenic modifications, they still maintained high natu- ral faunal diversities typical of inland Atlantic Forest sites in state of Bahia. The diversity and species richness observed in this study were actually greater than those reported in the literature for other semi-deciduous forests of the Atlantic fo- rest biome (Mentoni et al., 2011; Dias et al., 2008, Castilho et al., 2011). When the two fragments were compared, it could be seen that the numbers of species, genera, and sub-families were greater in fragment 1. This result suggests that although the two fragments were superficially similar, the first was bet- ter preserved in terms of the ecological niches available for the ant fauna and therefore better reflected the original com- munity structures of the Formicidae in this ecosystem; the second fragment represented a greater simplification of the more complex original community. The results presented here will hopefully be useful to future conservation plans for remnant forest areas in the Plan- alto da Conquista, as ants can be easily used as biological indicators of the degradation (or preservation) of areas sub- jected to anthropogenic impacts (or management). Addition- ally, it is hoped that this study will serve as a baseline for fur- ther investigations about regional biodiversity, as this region is desperately lacking this kind of information. Acknowledgments We would like to thank Drs. 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(1999) Effects of forest disturbance on the structure of ground-foraging ant communities in Central Ama- Freitas, JMS, Delabie, JHC & Lacau, S. - Leaf-litter Ant Communities in Bahia Atlantic Forest, Brazil 18 Appendix - List of ant species and their frequency of occurrence collected by two sampling methods and in two forest remnants in Barra do Choça, Bahia, Brazil: MW1 and MP1 represent the species collected with Winkler sacks and pitfall traps in first forest remnant; MW2 and MP2 represent the species collected with Winkler sacks and pitfall traps in the second forest remnant. Subfamilies Species MW1 MP1 MW2 MP2 Dolichoderinae Azteca sp. 1 1 7 Azteca sp. 2 1 Dolichoderus attelaboides (Fabricius, 1775) 1 1 Linepithema pulex Wild, 2007 20 27 Ecitoninae Eciton burchelli Westwood, 1842 1 Labidus praedator (Smith, 1858) 1 Ectatomminae Ectatomma edentatum Roger 1863 1 7 Ectatomma sp. 1 12 1 Ectatomma sp. 3 10 Gnamptogenys striatula Mayr, 1884 19 20 19 25 Formicinae Acropyga guianensis Weber, 1944 1 Acropyga sp. 1 1 Brachymyrmex patagonicus Mayr, 1868 4 6 Brachymyrmex sp. 1 7 Brachymyrmex sp. 3 2 6 Brachymyrmex sp. 4 8 Brachymyrmex sp. 5 6 1 Camponotus cingulatus Mayr, 1862 7 4 Camponotus novogranadensis Mayr, 1870 14 8 5 5 Camponotus renggeri Emery, 1894 1 Camponotus sp. 3 2 Camponotus (Tanaemyrmex) sp. 5 1 Nylanderia sp. 1 5 1 2 1 Nylanderia sp. 2 24 9 37 21 Nylanderia sp. 4 2 Nylanderia sp. 5 1 Paratrechina longicornis (Latreille, 1802) 1 Heteroponerinae Heteroponera mayri Kempf, 1962 3 6 Myrmicinae Acanthognathus sp 1 1 Acromyrmex aspersus (Smith, 1858) 1 Acromyrmex sp. 1 1 1 Apterostigma pilosum Mayr, 1865 3 zonia. Biodiversity and Conservation, 8: 409-420. Veiga-Ferreira, S., Mayhé-Nunes, A. J. & Queiroz, J. M. (2005). Formigas de Serapilheira na Reserva Biológica do Tinguá, Estado do Rio de Janeiro, Brasil (Hymenoptera: For- micidae). Revista da Universidade Rural, Sér. Ciênc. Vida.. Seropédica, 25: 49-54. Wilson, E. O. & Hölldobler, B. (2005) The rise of the ants: A phylogenetic and ecological explanation. PNAS, 102: 7411 – 7414. Wilson, E.O. (2003) The genus Pheidole in the New World: A Dominant, Hyperdiverse Ant Genus. Harvard University Press. Sociobiology 61(1): 9-20 (March, 2014) 19 Myrmicinae (cont.) Basiceros disciger (Mayr, 1887) 1 Carebara sp. 1 6 4 1 Carebara sp. 2 4 Crematogaster distans Mayr, 1870 2 1 Crematogaster sp. 2 1 5 1 Crematogaster sp. 3 1 Cyphomyrmex transversus Emery, 1894 7 2 5 1 Cyphomyrmex strigatus gp. sp. 1 1 Hylomyrma balzani (Emery, 1894) 18 7 19 3 Megalomyrmex drifti Kempf, 1961 1 Megalomyrmex goeldii Forel, 1912 7 8 Monomorium delabiei Fernández, 2007 1 Myrmicocrypta sp. 1 1 Myrmicocrypta sp. 2 4 Ochetomyrmex sp. 1 (LBSA 40 10 266) 1 1 Octostruma sp. 1 16 3 Oxyepoecus myops Albuquerque & Brandão, 2009 5 Oxyepoecus sp. 2 (LBSA_ 1 40 10 26 4) 4 2 Pheidole radoszkowskii Mayr, 1884 23 24 8 17 Pheidole tristis gp. sp. 1 1 Pheidole sp. 2 1 Pheidole fallax gp. sp. 3 1 1 1 6 9 Pheidole tristis gp. sp. 4 5 1 2 Pheidole sp. 5 6 4 1 Pheidole flavens gp. sp. 6 10 7 6 Pheidole tristis gp. sp. 7 2 4 2 Pheidole sp. 8 1 1 1 1 Pheidole diligens gp. sp. 9 1 1 Pheidole diligens gp. sp. 10 1 2 1 2 Pheidole fallax gp. sp. 11 1 3 Pheidole sp. 12 5 1 Pheidole tristis gp. sp. 13 4 1 Pheidole diligens gp. sp. 15 1 1 2 Pheidole sp. 17 1 1 Pheidole sp. 18 7 Pheidole sp. 21 1 2 Pheidole transversostriata Mayr, 1887 1 1 Procryptocerus hylaeus Kempf, 1951 1 Solenopsis sp. 3 2 2 Solenopsis sp. 4 17 Solenopsis sp. 6 1 3 2 22 1 3 Solenopsis sp. 7 1 Freitas, JMS, Delabie, JHC & Lacau, S. - Leaf-litter Ant Communities in Bahia Atlantic Forest, Brazil 20 Myrmicinae (cont.) Solenopsis sp. 8 3 Solenopsis sp. 9 8 6 14 3 Solenopsis sp. 10 1 Solenopsis sp. 11 1 Solenopsis sp. 12 2 1 4 1 Solenopsis sp. 13 18 2 5 1 Solenopsis sp. 14 1 Strumigenys appretiata (Borgmeier, 1954) 2 1 Strumigenys denticulata Mayr, 1887 2 Strumigenys sp. 1 2 Strumigenys sp. 2 9 2 Strumigenys sp. 3 5 1 Strumigenys sp. 4 11 8 Trachymyrmex sp. 1 1 Wasmannia auropunctata (Roger, 1863) 4 2 6 2 Wasmannia iheringi Forel, 1908 8 2 22 2 Wasmannia sp. 3 4 Ponerinae Anochetus simoni Emery, 1890 3 Hypoponera foreli (Mayr, 1887) 5 5 2 Hypoponera sp. 1 3 Hypoponera sp. 2 5 2 20 1 Hypoponera sp. 3 24 20 Hypoponera sp. 5 1 Hypoponera sp. 6 9 Hypoponera sp. 7 3 Odontomachus chelifer (Latreille, 1802) 9 8 Odontomachus sp. 2 3 3 1 Odontomachus sp. 3 1 Pachycondyla crenata (Roger, 1861) 1 Pachycondyla moesta Mayr, 1870 1 1 Pachycondyla nr. magnifica 7 34 Proceratiinae Discothyrea sexarticulata Borgmeier, 1954 1 22 1 Pseudomyrmecinae Pseudomyrmex tenuis (Fabricius, 1804) 1 1 1