Check List 8(4): 722–730, 2012 © 2012 Check List and Authors Chec List ISSN 1809-127X (available at www.checklist.org.br) Journal of species lists and distribution Check list of ground-dwelling ants (Hymenoptera: PECIES S Formicidae) of the eastern Acre, Amazon, Brazil OF Patrícia Nakayama Miranda 1,2*, Marco Antônio Oliveira 3, Fabricio Beggiato Baccaro 4, Elder Ferreira ISTS 1 5,6 L Morato and Jacques Hubert Charles Delabie 1 Universidade Federal do Acre, Centro de Ciências Biológicas e da Natureza. BR 364 – Km 4 – Distrito Industrial. CEP 69915-900. Rio Branco, AC, Brazil. 2 Instituo Federal do Acre, Campus Rio Branco. Avenida Brasil 920, Bairro Xavier Maia. CEP 69903-062. Rio Branco, AC, Brazil. 3 Universidade Federal de Viçosa, Campus Florestal. Rodovia LMG 818, Km 6. CEP 35690-000. Florestal, MG, Brazil. 4 Instituto Nacional de Pesquisas da Amazônia, Programa de Pós-graduação em Ecologia. CP 478. CEP 69083-670. Manaus, AM, Brazil. 5 Comissão Executiva do Plano da Lavoura Cacaueira, Centro de Pesquisas do Cacau, Laboratório de Mirmecologia – CEPEC/CEPLAC. Caixa Postal 07. CEP 45600-970. Itabuna, BA, Brazil. 6 Universidade Estadual de Santa Cruz. CEP 45650-000. Ilhéus, BA, Brazil. * Corresponding author. E-mail: [email protected] Abstract: The ant fauna of state of Acre, Brazilian Amazon, is poorly known. The aim of this study was to compile the species sampled in different areas in the State of Acre. An inventory was carried out in pristine forest in the municipality of Xapuri. This list was complemented with the information of a previous inventory carried out in a forest fragment in the municipality of Senador Guiomard and with a list of species deposited at the Entomological Collection of National Institute of Amazonian Research– INPA. The resulting list covered 268 species distributed in 52 genera and nine subfamilies, and records 23 inventories will be crucial to properly describe and understand ant species distribution patterns in southwestern Amazon. species and four morphospecies for the first time in the state of Acre. Due to the large environmental heterogeneity, future Introduction municipality of Senador Guiomard (Oliveira et al. 2009) Although tropical forests represent only 7% of the with a recent ant survey carried out in a pristine forest planet´s surface, these ecosystems host more than a half area, located at Projeto de Assentamento Agroextrativista of known species of plants and animals (Wilson 1988; May (PAE) Chico Mendes, Xapuri, as well as ant species material 2010). Paradoxically, a large amount of species found in kept at the Entomological Collection of Instituto Nacional tropical forests are associated with a relatively low number de Pesquisas da Amazônia – INPA. of inventories, limiting the knowledge about taxonomy and geographic distribution of species (Dourojeanni 1990). Material and Methods Study Area the sate of Acre, west of the Brazilian Amazon. Ants were sampled in two areas situated in the west ThisSeveral fact can studies be found on in faunisticplants (Silveira and floristic et al.studies 1997; in of the state of Acre: Fazenda Experimental Catuaba (FEC) Goldenberg and Meirelles 2011), mammals (Calouro and Projeto de Assentamento Agroextrativista (PAE) 1999), birds (Whitaker and Oren 1999; Guilherme Chico Mendes (Figure 1), separated from each other by 2001; Guilherme and Borges 2011), amphibians (Lima approximately 110 km. Both areas are located in a slightly et al. 2007) and some arthropod groups (Morato 2001; undulating terrain, characterized by soil of sedimentary Villarreal-Manzanilla and Pinto-Da-Rocha 2006; Oliveira origin. The climate is equatorial warm and humid, with et al. 2009; Carvalho and Esposito 2010) suggests a large the average annual temperature around 24.5°C (maximum diversity and endemism in forested areas of Acre. However, of 32°C). The annual rainfall varies between 1,600 mm to the distribution of terrestrial invertebrates is relatively 2,750 mm, with two marked seasons: the dry season (< unknown (Morato et al. 2005). For example, to our 100 mm/month) goes from July to August and the rainy knowledge, only one ant survey carried out in Acre state season (> 300 mm/month) from May to October (Acre was published until now (Oliveira et al. 2009), although 2006). these insects are frequently mentioned as key-organisms to Fazenda Experimental Catuaba (10°04’ S e 67°37’ W) the functioning of tropical forests by changing the physical covers an area of 1,116 ha of dense rain forest, located in and chemical soil structure (Folgarait 1998; Moutinho et the municipality of Senador Guiomard. The vegetation is al. 2003, Sousa-Souto et al. 2007), seed dispersion (Handel and Beattie, 1990, Levey and Byrne, 1993) and control The understory is relatively dense and characterized by of herbivorous insect population (Dyer and Letourneau the“terra-firme” abundance non-flooded of palms trees, rain forestbamboos with and closed lianas. canopy. The 1999). canopy height is of 30–37 m with some emergent trees The aim of this study was to compile the occurrences reaching up to 40 m. Besides the primary forest, there of species sampled at different areas in the state of are other secondary forest formations (capoeira) and Acre. We organized the information available from a abandoned pasture (see Oliveira et al. 2011, for detailed previous inventory undertaken in a forest fragment in the information). 722 Miranda et al. | Ground-dwelling ants of the eastern Acre, Brazil Projeto de Assentamento Agroextrativista (PAE) Chico between approximately 4 km and 12 km. In each area, Mendes (10° 53’ S e 68° 21’ W) is an area of 24,898 ha (Acre ants were sampled by pitfall traps (9 cm diameter plastic 2006), located in the municipality of Xapuri, Acre, Brazil cup) in two 10 ha plots, totaling 18 plots (nine in managed (Acre 2009). Approximately 84 families are distributed in areas and nine plots in unmanaged areas). In each plot, PAE Chico Mendes. These families carry out the collection two 200 m-long parallel transects 50 m from each other, of Brazilian nuts (Bertholletia excelsa Kunth), latex (Hevea were established in the center of the plot. Ten pitfall traps brasiliensis (Willd. Ex A. Juss) Mull. Arg.) extractivism, were installed every 20 m along each transect, totalizing and some families develop the sustainable low intensity 360 traps (20 per plot). The pitfalls had a solution of 70% forest management (5.4m3/ha). Approximately 90% of the alcohol and were left open for four days before being area is covered by forests (Coopeagro 2001), which the removed. principal vegetation formations are represented by open forest dominated by bamboo, open forest dominated by (Fernández 2003; Wilson 2003; Hölldobler and Wilson palms and dense rain forest (Acre 2006). 1990)Ants and were by sorted comparison and identified with specimensusing taxonomic deposited keys at Entomological Collection of INPA, Regional Museum Sampling of Universidade Federal de Viçosa and Laboratório de At FEC ants were sampled using pitfall traps installed Mirmecologia do Centro de Pesquisas do Cacau (CEPEC/ in nine plots of approximately 1 ha (90 x 80 m). Three plots were established in primary forests; three in species level were named with a unique code, thus the approximately 19 years old secondary forests; and three morphotypesCEPLAC). The sampled taxa that in PhadAE Chico not Mendesbeen identified were inde toxed a in secondary managed forests (burned, deforested and with morphotypes sampled in FEC. Voucher specimens of left for regeneration since 2001). The distance between FEC surveys were deposited at Entomological Collection areas varied of 0.1 to 6.5 km. In each area 20 pitfalls were of Universidade Federal do Acre, Regional Museum of Universidade Federal de Viçosa and Centro de Pesquisas days. The samples were done from June 2001 to January do Cacau (CPDC collection, CEPEC/CEPLAC). A full 2005,installed totaling every 2,400 25 m. pitfalls The traps (Oliveira remained et al. in 2009; field for2011). seven reference collection of PAE Chico Mendes was deposited Ants were sampled in nine sustainable low intensity in Entomology Collection of INPA and Entomological forest management areas at PAE Chico Mendes during Collection of Universidade Federal do Acre. August and September 2010. Areas were chosen in order The nomenclature followed Bolton et al. (2005), with to cover the different forests structures found on the subsequent amendments available at the Online Catalog settlement project. The distance between areas varied of the Ants of the World (AntCat) web site (http://antcat. Figure 1. Map of the sampling areas and additional information about ant species distribution available for the state of Acre. 723 Miranda et al. | Ground-dwelling ants of the eastern Acre, Brazil org/catalog/index). Fr. Smith, 1855 was the only species deposited at Coleção de Invertebrados do INPA, which were not sampled in FEC Data analyses and PAE Chico Mendes. Because the sampling units and pitfall trap density As in other Amazon areas, the subfamily Myrmicinae were different, species rarefaction curves were used to showed a higher number of species. In soil and leaf litter compare species richness between areas. The rarefaction ants inventories, this subfamily is normally the most curves were generated by random samples of species frequent and diverse, probably because it comprises occurrence without replacement in Estimate S 8.20 generalist species, specialists predators and fungus- software (Colwell 1997), using the Coleman method growing ants which have different nesting habitats, such as (Coleman 1981). As ants are colonial organisms and often rotting wood, soil, leaf litter and on the vegetation (Fowler use established pheromone trails, using abundance of et al. 1991). The subfamilies that harbor strictly or partially individuals may alter diversity estimates (Longino et al. arboreal species, such as Pseudomyrmecinae (Ward 2002). Therefore, the rarefaction curves were built using 1999) and Dolichoderinae (Shattuck 1992), probably the species frequency instead of worker numbers (Colwell were underestimated due to the sampling methods used and Coddington 1994; Gotelli and Colwell 2001).