Plowmania nyctaginoides

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Plowmania nyctaginoides
Systematics
Asterids
Euasterids I
Order : Nightshade (Solanales)
Family : Nightshade family (Solanaceae)
Genre : Plowmania
Type : Plowmania nyctaginoides
Scientific name of the  genus
Plowmania
Hunz. & Subils
Scientific name of the  species
Plowmania nyctaginoides
( Standl. ) Hunz. & Subils

Plowmania nyctaginoides is a plant type from the family of nightshade family (Solanaceae), which so far only in southern Mexico and Guatemala was found. It is the only species in the genus Plowmania .

description

Vegetative characteristics

Plowmania nyctaginoides are 0.9 to 1.5 m high, mostly climbing plants. The cortex of the shoot axis has strengthening tissue ( collenchyma ), the endodermis lacks a starchy sheath, as can be found in the possibly closely related leptoglossis . The pericycle is fibrous, the medulla consists of parenchymal tissue . Both the bark and the pulp are glandular. The leaves stand on petioles up to 1 cm long, the leaf blades are 3 to 10 cm long, oval-elliptical and have a dorsiventral mesophyll .

blossoms

The calyx of the flower is bell-shaped and about 10 mm long. The crown is funnel-shaped, slightly bulbous and very conspicuous, brightly colored: the corolla tube is orange with a greenish base, the corolla lobes are vermilion, flamed to scarlet, the throat is golden-yellow. The edge of the petals has a width of about 19 to 25 mm. The four stamens come in two different forms: The upper pair has longer stamens than the lower pair. The anthers are the same in both stamen types, about 2 mm long, the counters are separated from each other. The pollen is slightly flattened and medium-sized at around 30 µm. A circular, showy nectarium exists in the flowers .

Fruits and seeds

The fruits of the species are many-seeded capsules , which probably crack open with two chambers. The pericarp is leathery. Mature seeds have not yet been found; the immature seeds found on the plants observed had a size of 1.2 to 1.6 mm.

Distribution and location

So far (as of 2001) the species is only known from seven collections. All finds come from the volcanic mountains of southern Mexico and Guatemala and from altitudes between 1800 and 3800 m.

Systematics

Due to the rarity of the species, a reliable classification in the systematics of the nightshade family is very difficult. Armando Hunziker provisionally places them together with the genera Leptoglossis and Hunzikeria in the subtribe Leptoglossinae of the tribe Nicotianeae of the subfamily Cestroideae. He justifies this placement with the correspondence of the floral characteristics, but also mentions a possible close relationship to the Brunfelsia , whose stem axis anatomy corresponds to that of Plowmania nyctaginoides . A more precise placement will only be possible with further collections through which the properties of mature seeds, young flower buds or the karyotype can be determined.

The name of the genus honors the American botanist Timothy Charles Plowman (1944 - 1989), who first suspected that the species initially assigned to the genus Brunfelsia belongs to a different genus.

literature

  • Armando T. Hunziker: The Genera of Solanaceae . ARG Gantner Verlag KG, Ruggell, Liechtenstein 2001. ISBN 3-904144-77-4 .

Individual evidence

  1. ↑ Lotte Burkhardt: Directory of eponymous plant names . Extended Edition. Botanic Garden and Botanical Museum Berlin, Free University Berlin Berlin 2018. [1]

Web links