Information:  - Cornaceae is a cosmopolitan family of flowering plants in the order Cornales. It contains approximately 85 species in two genera, "Alangium" and "Cornus". They are mostly trees and shrubs, which may be deciduous or evergreen, although a few species are perennial herbs. Members of the family usually have opposite or alternate simple leaves, four- or five-parted flowers clustered in inflorescences or pseudanthia, and drupaceous fruits. In northern temperate areas, Cornaceae are well known from the dogwoods "Cornus".  - An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. Inflorescence can also be defined as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern.  - Alangium is a small genus of flowering plants. The genus is included either in a broad view of the dogwood family Cornaceae, or as the sole member of its own family Alangiaceae. "Alangium" has about 40 species, but some of the species boundaries are not entirely clear. The type species for "Alangium" is "Alangium decapetalum", which is now treated as a subspecies of "Alangium salviifolium". All of the species are shrubs or small trees, except the liana "Alangium kwangsiense". "A. chinense, A. platanifolium", and "A. salviifolium" are known in cultivation.  - Cornus is a genus of about 3060 species of woody plants in the family Cornaceae, commonly known as dogwoods, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous trees or shrubs, but a few species are nearly herbaceous perennial subshrubs, and a few of the woody species are evergreen. Several species have small heads of inconspicuous flowers surrounded by an involucre of large, typically white petal-like bracts, while others have more open clusters of petal-bearing flowers. The various species of dogwood are native throughout much of temperate and boreal Eurasia and North America, with China and Japan and the southeastern United States particularly rich in native species.  - Mastixia glauca is a tree in the family Cornaceae . The specific epithet glauca is from the Greek meaning `` bluish - grey '' , referring to the colour of the leaf underside .  - The Cornales are an order of flowering plants, basal among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior gynoecia topped with disc-shaped nectaries.    Given the information above, choose from the list below the object entity that exhibits the relation 'taxon rank' with the subject 'mastixia glauca'.  Choices: - family  - genus  - group  - order  - species
A:
species