利用光学显微镜对鼠刺属(Itea Linn.)13种常见植物开展叶表皮微形态特征研究,基于最小数据集法筛选出关键分类鉴定指标,编制了鼠刺属13种植物的分类检索表，为该属物种鉴定提供必要的依据。结果表明:鼠刺属13种植物上、下表皮细胞的垂周壁式样存在较大差异,均分为微波状、波状、深波状弯曲3种类型；上、下表皮还观察到单细胞非腺毛、多列多细胞腺毛及腺鳞等附属物的存在,附属物在部分近缘物种间〔如冬青叶鼠刺(I. ilicifolia Oliv.)与滇鼠刺(I. yunnanensis Franch.)、河岸鼠刺(I. riparia Collett et Hemsl.)与秀丽鼠刺(I. amoena Chun)〕差异明显。基于最小数据集法筛选出上表皮细胞长宽比、上表皮细胞周长、上表皮细胞面积、气孔器面积、气孔密度和气孔指数6个关键分类鉴定指标,其数值范围分别为1.75～2.29、87.29～186.23 μm、342.60～911.11 μm²、105.69～414.21 μm²、561～912 mm^-2、15.68%～29.83%；其中,上表皮细胞面积、气孔器面积显示的显著差异数量最多(均为64),其后依次为上表皮细胞周长(57)、气孔指数(47)、气孔密度(27)、上表皮细胞长宽比(6)。对于通过叶表皮细胞垂周壁式样以及附属物难以鉴别的部分近缘物种,如峨眉鼠刺(I. omeiensis C. K. Schneid.)、鼠刺(I. chinensis Hook. et Arn.)、腺鼠刺(I. glutinosa Hand.-Mazz.),可借助上述6个指标实现更为有效的区分。综上表明,鼠刺属13种植物的叶表皮微形态特征差异明显,具有重要的分类价值；筛选出的上表皮细胞长宽比等6个指标可用于有效区分鼠刺属13种植物。

 The leaf epidermal micromorphological characters of 13 common species in Itea Linn. were studied by using optical microscope, key taxonomic identification indexes were selected based on the minimum data set method, and a taxonomic key for the 13 Itea species was compiled, providing essential criteria for species identification of the genus. The results show that there are relatively large differences in anticlinal wall patterns of the upper and lower epidermal cells of the 13 Itea species, and they can be classified into three types, namely slightly sinuous, sinuous, and deeply sinuous curve; appendages such as single-celled nonglandular trichome, multiseriate multicellular glandular trichome, and glandular scale are observed on the upper and lower epidermides, with distinct variations among some closely related species (e.g., I. ilicifolia Oliv. and I. yunnanensis Franch., I. riparia Collett et Hemsl. and I. amoena Chun). Based on the minimum data set method, six key taxonomic identification indexes are selected, namely length-width ratio of upper epidermal cell, upper epidermal cell perimeter, upper epidermal cell area, stomatal apparatus area, stomatal density, and stomatal index, and their value ranges are 1.75-2.29, 87.29-186.23 μm, 342.60-911.11 μm², 105.69-414.21 μm², 561-912 mm^-2, and 15.68%-29.83%, respectively; among which, upper epidermal cell area and stomatal apparatus area show the highest number of significant differences (both are 64), followed by upper epidermal cell perimeter (57), stomatal index (47), stomatal density (27), and length-width ratio of upper epidermal cell (6). For some closely related species difficult to distinguish via anticlinal wall patterns and appendages, such as I. omeiensis C. K. Schneid., I. chinensis Hook. et Arn., and I. glutinosa Hand.-Mazz., can be utilized to achieve more effective differentiation by the above six indexes. In conclusion, the leaf epidermal micromorphological characters of the 13 Itea species exhibit evident differences, demonstrating an important taxonomic value; the six selected indexes, including lengthwidth ratio of upper epidermal cell, can effectively distinguish the 13 Itea species.