Asclepias nyctaginifolia

Asclepias nyctaginifolia

Asclepias nyctaginifolia is a species of the genus milkweed ( Asclepias ) from the subfamily of milkweed plants ( Asclepiadoideae ). It occurs in the southwestern United States and northern Mexico.

• 4.1 Literature
• 4.2 Notes and references

Description

Appearance and leaf

Asclepias nyctaginifolia grows as a low, perennial herbaceous plant, the plant height of 15 to 20 cm (or 10 to 40 cm, exceptionally to 60 cm ) is reached. The relatively slender, finely hairy fluffy stems ascending or lying, standing at the base close together and branch out a little above the base. The oppositely arranged leaves are continually divided into petiole and leaf blade. The petiole is 1 to 3 cm long. The Spreitenbasis is broadly obtuse or rounded, and runs pretty abruptly cuneate into the petiole. The membranous, dark green, simple leaf blade is at a length of 6 to 10 cm and a width of 2 to 4 cm ovate to almost rhomboidal with a blunt or pointed top. Both leaf surfaces are hairy fine fluffy, especially the bottom. The leaf margins are usually wavy.

Inflorescence and flower

The flowering period extends in the home area of ​​May to August. The almost without inflorescence stem laterally at some of the top nodes ( more nodes ) standing inflorescences contain only a few flowers. The approximately 2 cm long flower stems are hairy and stiff fine fluffy.

The comparatively large, hermaphroditic flowers are radial symmetry and fünfzählig. The five fine fluffy hairy sepals are ovate - lanceolate grown at a length of about 4 mm only at their base. The five petals are most reflexed far, the corolla lobes are 12 to 14 mm (12 to 16 mm ) long. They are greenish yellow in color, with a tinge of purple externally colored. The short- conical, about 0.5 mm high and 1 mm wide pedunculated Gynostegium is pale greenish - cream color. The staminal Nebenkronzipfel are at a length of 8 to 11 mm (about 1 cm ) and at the upper end of a width of 2 to 3 mm or ovoid elongate and rounded at its base. The top of the staminal Nebenkronzipfel is rounded and very slightly wavy. So you tower over the Gynostegium to 4-7 mm. The inner secondary extensions are horn-shaped and almost completely fused with the staminal Nebenkronzipfeln; only a pointed, tooth-like, about 1 mm long projection is still free and are slightly shorter than the staminal Nebenkronzipfel. The stylus head is broad - tapered, about 2 mm long and 3 mm wide.

Fruit and seed

The upright, standing on the bent stems follicles are thick and short fusiform tipped up with a length of 3 to 5 cm and a diameter of 1.5 to 3 cm. They are finely pubescent or glabrous. The seed is not known.

Synecology

Asclepias nyctaginifolia is an important food plant for the caterpillars of the butterfly Danaus precious gilippus.

Occurrence

Asclepias nyctaginifolia occurs only in the southwestern U.S. states of Arizona, California and New Mexico as well as in the northern Mexican state ( state of Sonora ).

It grows along gullies, temporary watercourses, springs, valleys, slopes and meadows and in open woods and along roads through the desert. Asclepias nyctaginifolia thrives in altitudes between 500 to 2000 meters.

Swell