Plant galls are formed from abnormal vegetative growth produced by a plant under the influence of an insect, mite, bacteria, fungus or nematode. Galls can be found on any part of the plant, bark, flowers, buds, acorns or roots, but are most often observed as large, swollen growth on a leaf or branch. Our objective was to characterize leaf galls on Laguncularia racemosa (Combretaceae), and the influence of the raining season in its population demography. This study was conducted at mangrove of Maracaípe (Ipojuca, PE). Six sites differing in soil distance from ocean and estuary were chosen for this study. In each site, 30 x 30 m plot was established. In each site, 40 leaves with galls from the 2º or 3º pair of leaves of different plants were collected, monthly (November/2004 to October 2005). Forty leaves without galls were collected in January (dry season) and July (rainy season) to compare leaf areas. L. racemosa gall is induced by a new species of mite (Acari, Eriophyidae). The gall is green, discoid, and prominent to both leaf surfaces (1.5 ± 0.23 x 1.0 ± 0.14 mm). We observed an average of 35 ± 4.4 (N = 50 galls) adults per gall. There was a preferential trend to gall induction next to the leaf apex. The comparison between leaf areas with and without galls presented a significant difference only at the rainy season, when the number of galls was significantly lower, perhaps as a consequence of the higher leaf production during this season and/or due to the restricted mites locomotion caused by the rain.
Eriopyidae; galls; Mangrove
