The Genus Lonicera
Orange Honeysuckle: Lonicera ciliosa - Stems climbing. Flowers are in clusters, orange, and tubular in shape, subtended by the large, rounded (perfoliate) leaf. Corollas 2.5-3 cm long.
Double Honeysuckle, Purpleflower Honeysuckle, Purple-flower Honeysuckle, Purple-flowered Honeysuckle: Lonicera conjugialis - Stems erect, forming a small bush to 1.5 meters high. Flowers are dark red to purplish-brown, not subtended by colored involucres. Ovaries largely fused.
Etruscan Honeysuckle: Lonicera etrusca - Stems climbing. Uppermost pair of opposite leaves with their bases not fused completely around the stem as in #1 above). Corollas purplish to yellow, 3-5 cm long.
Bearberry, Black Twinberry, Black Twin-berry, Twinberry, Twinberry Honeysuckle: Lonicera involucrata var. involucrata (Synonyms: Distegia involucrata, Lonicera involucrata var. flavescens, Xylosteum involucratum) - Stems erect, forming a small bush to 3 meters tall. Flowers are yellowish, in pairs subtended by a dark red to purplish involucre. Ovaries not fused.
Red Twinberry, Rocky Mountain Honeysuckle Utah Honeysuckle: Lonicera utahensis (Synonym: Lonicera ebractulata) - Stems erect, forming a small bush to 2 meters tall. Flowers are pendant, whitish and not subtended by colored involucres. Ovaries only slightly united.