Data from: Temporal variation in the abundance and richness of foliage-dwelling ants mediated by extrafloral nectar

Plants bearing extrafloral nectaries (EFNs) are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1) EFN-bearing plants are more visited by ants than EFN-lacking plants; 2) ant visitation is higher in the rainy season than in dry season; 3) plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4) during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5) the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2), in the rainy (October-January) and dry seasons (April-July) of 2010-2011. Plants (72 species; 762 individuals) were checked three times per season for ant presence. Results showed that 21 species (29%) and 266 individuals (35%) possessed EFNs. These plants attracted 38 ant species (36 in rainy, 26 in dry season). In the rainy season, plants with EFNs had higher ant abundance/richness than plants without EFNs, but in the dry season, EFN presence did not influence ant visitation. Plant phenology affected ant richness and abundance in different ways: plants with young leaves possessed higher ant richness in the rainy season, but in the dry season ant abundance was higher on plants possessing old leaves or flowers. The species composition of plant-associated ant communities, however, did not differ between plants with and without EFNs in either season. These findings suggest that the effect of EFN presence on a community of plant-visiting ants is context dependent, being conditioned to seasonal variation.具有花外蜜腺（extrafloral nectaries, EFNs）的植物在巴西塞拉多稀树草原中十分常见，该区域气候具有显著的季节性变化，这对树栖蚂蚁类群的群落结构具有显著影响。这类蚁植相互作用在群落尺度上的研究尚属罕见。本研究旨在检验以下5个假设：1. 具花外蜜腺植物的蚂蚁访问频次高于无花外蜜腺植物；2. 雨季的蚂蚁访问频次高于旱季；3. 雨季中，长出新叶的植物的蚂蚁访问频次高于无新叶的植物；4. 旱季中，具有老叶与花的植物的蚂蚁访问频次高于长有新叶或无叶无花的植物；5. 具与无花外蜜腺植物的来访蚂蚁类群组成存在差异。本研究于2010-2011年的雨季（10月至次年1月）与旱季（4月至7月）在巴西米纳斯吉拉斯州乌贝兰迪亚附近的一处塞拉多保护区开展，沿10条样带（总面积3000平方米）进行调查。本研究共调查72种共762株植物，每个季节对其进行3次蚂蚁存在性检查。调查结果显示，72种植物中有21种（占比29%）、762株个体中有266株（占比35%）具有花外蜜腺；这类植物共吸引了38种蚂蚁（雨季36种，旱季26种）。雨季中，具花外蜜腺植物的蚂蚁多度与类群丰富度均高于无花外蜜腺植物；但在旱季，花外蜜腺的存在对蚂蚁访问频次无显著影响。植物物候对蚂蚁类群丰富度与多度的影响存在差异：雨季中，长有新叶的植物蚂蚁类群丰富度更高；而旱季中，具有老叶或花的植物蚂蚁多度更高。不过，无论在雨季还是旱季，具与无花外蜜腺植物的伴生蚂蚁群落组成均无显著差异。本研究结果表明，花外蜜腺的存在对植物访蚁群落的影响具有情境依赖性，其效应受季节性变化调控。