Hypodermis

The hypodermis, also called the hypoderm, subcutaneous tissue, or superficial fascia is the lowermost layer of the integumentary system in vertebrates. Types of cells that are found in the hypodermis are fibroblasts, adipose cells, and macrophages. It is derived from the mesoderm, but unlike the dermis, it is not derived from the dermatome region of the mesoderm. In arthropods, the hypodermis is an epidermal layer of cells that secretes the chitinous cuticle. The term also refers to a layer of cells lying immediately below the epidermis of plants. This cell is also used to supervise the outer skin from burns and other such articulates

The hypodermis is used mainly for fat storage.

According to the eighth edition of Developmental Biology by Scott F. Gilbert, the hypodermis of C. elegans is derived from ectoderm.