Schiedea apokremnos is a gynodioecious shrub. The stems are often swollen at the nodes, terete (cylindrical), 4–angled or ridged, and measure 20–40 (–50) cm long. They are branching, with the lowermost branches ascending or decumbent and the flowering branches strongly ascending. Stems are glabrous with internodes measuring 0.3–0.9 (–1.3) cm long and are either green or purple. The leaves are simple, opposite, with oblanceolate or elliptic–oblanceolate blades that measure (1.5–) 3–5.5 (–8.3) cm long and (0.3–) 0.6–1.4 cm wide. The apex is acute to obtuse, and leaf bases are often connate around the stem, attenuating at the base. Blades are weakly succulent and glaucous, with entire and slightly thickened margins. Only the midvein is evident, and petioles measure 0–0.4 cm long. Stipules are absent. The flowers occur in terminal inflorescences that are 0.3–6 cm long, often congested, head-like, or slightly open. Hermaphroditic inflorescences are 1.5–4.8 cm long, with 26–93 flowers, and are broader than the pistillate inflorescences, which measure 0.3–6 cm long and contain 39–140 flowers. Bracts are 2–3.5 mm long on the central axis and 1–1.5 mm on branches and flowers, linear to subulate, and green or purple-tinged. Hermaphroditic flowers have 2–2.85 mm long sepals, broadly ovate, green or tinged purple, glabrous with scarious margins, and an obtuse apex. Pistillate flowers have sepals that measure 2.05–3.1 mm long, broadly ovate, green or purple-tinged, with entire, scarious margins. There are no petals. Hermaphroditic flowers have 9–10 stamens with slightly dimorphic filaments, while pistillate flowers have vestigial stamens that do not produce pollen. The ovary is superior and 1-celled, with free-central placentation and 3 (–4) styles. The capsules (fruit) are broadly ovoid, 1.5–2.5 mm long. Seeds are 0.6–0.8 mm long, orbicular–reniform, compressed, with a papillose surface and starchy perisperm. A true endosperm is absent. It grows on dry coastal cliffs, especially in leeward crevices of shrublands between 60–400 (–610) meters.
Bean-shaped (Reniform): Resembling the shape of a kidney or bean.
Square or Oblong: Angular shape with all sides more or less equal or longer than wide.
Triangular: Three-sided shape, broadest below the middle.
Elliptic: Rounded at both ends. shaped like an ellipse or oval.
Ovate or Obovate: egg-shaped, broader at one end.
Linear: Extremely long and narrow, with sides usually parallel.
Round: Appears circular, with length and width roughly the same.
Cardioid (Heart-Shaped): One edge has a prominent double curve into two lobes.
Cylindrical: A cylinder with parallel sides and a circular cross-section.
Discoid: Resembling a disc or plate with two relatively flat surfaces.
Fusiform: Spindle-shaped, tapering at both ends.
Globose: Spherical.
Lenticular: Resembling a lens with two convex surfaces.
Ovoid: Egg-shaped.
Plano-convex: Having a flat ventral (planar) surface and a curved dorsal (convex) surface.
Polygonal: Having more than three flat faces meeting at angles.
Sectoroid: Resembling a segment of an orange with two relatively flat faces and one curved face.
Subglobose/ellipsoid: Inflated shape but less than spherical.
Trigonous: Having three faces that meet at a distinct angle; triangular in cross-section.
Endangered species (E) are species that are so rare they’re in danger of becoming extinct.
Threatened species (T) are species that are likely to become endangered within the foreseeable future throughout all or a significant portion of their range.
Species of Concern (SOC) are species about which there are some concerns regarding status and threats, but insufficient information is available to list the species under the Endangered Species Act (ESA).
Plant Extinction Prevention (PEP) is a state status for rare plants that focuses its efforts on species that have fewer than 50 remaining wild individuals.
Orthodox seeds (desiccation-tolerant): can be dried to an internal seed moisture of less than 12% water and stored at freezing temperatures.
Intermediate seeds (temperature-sensitive) tend to age faster than orthodox seeds and may have only a 5-year lifespan when stored at -20°C. They are recommended for storage at 5°C.
Recalcitrant seeds (desiccation-sensitive): cannot be stored in a conventional freezer as they cannot survive after drying and/or freezing at -20°C. They are recommended for cryopreservation storage.