Rutaceae species, especially of the genus Zanthoxylum L., are known for possessing a well-diversified chemical composition with high potential for pharmacological activity. A variety of Zanthoxylum species are distributed throughout Brazil. This study aimed to characterize the leaf anatomy and identify the histochemical composition of the secretory material from the secretory structures of Z. caribaeum leaves. Leaves of Z. caribaeum were collected and processed for anatomical, histochemical and micromorphological characterization following standard methodologies. The leaves have an unstratified epidermis and glandular trichomes in epidermal depressions on the abaxial surface. Extrafloral nectaries were also observed on the abaxial surface. The leaf is hypostomatic and the stomata are anomocytic. The mesophyll is dorsiventral and has secretory cavities. The mesophyll cavities produce a secretion of lipidic nature and the cavities on the leaf margin produce a secretion of mixed nature, with neutral lipids and essences. In summary, our findings show that the leaves of Z. caribaeum have secretory structures like glandular trichomes that can function as extrafloral nectaries and cavities. The characterization of the leaf anatomy of Z. caribaeum can provide relevant data for future taxonomic studies of the genus.

芸香科物种，特别是花椒属（Zanthoxylum L.）属，因具有良好的化学组成而具有很高的药理活性潜力。巴西的花椒种类繁多。这项研究旨在表征叶片的解剖结构，并从Z. caribaeum叶片的分泌结构中识别出分泌材料的组织化学组成。叶Z. caribaeum收集并处理后，按照标准方法进行解剖，组织化学和微形态学表征。叶片的背面表皮凹陷处有未分层的表皮和腺毛。在背面也观察到花蜜。叶片是气孔的，气孔是胞质的。叶肉是背叶的，有分泌腔。叶肉腔产生脂质性质的分泌物，叶缘的腔中产生混合性质的分泌物，具有中性脂质和香精。总而言之，我们的发现表明，Z。caribaeum的叶子具有像腺毛的分泌结构，可以充当花蜜和腔。叶片解剖特征Z. caribaeum可以为该属的未来分类学研究提供相关数据。