Markea

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Markea
Systematics
Nuclear eudicotyledons
Asterids
Euasterids I
Order : Nightshade (Solanales)
Family : Nightshade family (Solanaceae)
Genre : Markea
Scientific name
Markea
Rich.

BrandA is a plant genus of the family of the nightshade family (Solanaceae). The 11 to 20 species ,depending on the author, usually grow epiphytically . The generic name honors the French natural philosopher and botanist Jean-Baptiste Pierre Antoine de Monet Chevalier de Lamarck (1744-1829).

description

Vegetative characteristics

Markea are epiphytic plants that grow mostly as lianas , more rarely as upright or prostrate shrubs (rarely only 1) 1.5 to 3.5 m in height. Only in exceptional cases are there trees up to 6 m high . Thickening often occurs at the roots. The plants can be myrmekophil . They are covered with a multitude of differently shaped hairs , these can be simple, branched and tree-shaped, there are also glandular hairs with multicellular heads and a two-celled stem. The stem axis is (probably in all cases) hollow and reaches a diameter of up to 8 cm.

The leaves are tufted (seemingly lively ) in groups of three to six. The leaf blade is mostly membrane-like, rarely leathery and thick, it is narrow or broadly elliptical or, conversely, ovoid-elliptical. The base is pointed, pointed, rounded or heart-shaped, often running down on the stem; the tip is usually pointed, less often pointed, blunt or rounded. In some species the leaf blades have an average size of (2.1) 4.5 to 9 (13) × 2 to 5 (6.8) cm, in other species they are larger, then (7) 10 to 22 (31) × (2.9) 4 to 10 (14) cm. The petioles are 6 to 25 (60) mm long.

Inflorescences and flowers

The fragrant, sometimes foul-smelling or even odorless flowers are solitary, only in exceptional cases in pairs or in two- to ten-flowered (in exceptional cases up to seventeen-flowered) zymose inflorescences . The inflorescence stalks are either (3) 12 to 30 (50) cm long, thread-like, flexible and upright or only 0.3 to 16 cm long, thick, rigid and woody. The flower stalks are either only 1.5 to 7 mm long or longer and then 15 to 25 mm, rarely up to 63 mm long. The flowers are only sessile in exceptional cases. The sepals are often not overgrown, so that the calyx tube is very short or almost non-existent. Sometimes the calyx tube is stronger, but mostly shorter than the calyx lobes, only in exceptional cases is the calyx tube longer. The crown is colored red, orange-red, yellowish-orange, yellow-greenish, greenish, greenish-white, violet or blackish-violet. It is often divided into the two sectors typical of the subfamily Juanulloideae, the lower, shorter tubular and the upper long funnel-shaped. However, some species also have over-cup-shaped or funnel-shaped crowns. The length of the crown is variable, it is usually between 4.5 and 11 cm, in two types they are also longer and in one type ( M. sturmii ) the crown is only about 2.45 cm long. The corolla lobes are wider than they are long and usually curved back.

In some species the stamens protrude beyond the crown. The anthers are fixed to the base, about 9.5 to 18 mm long, in some species hardly 6 to 9.5 mm, they are usually inclined together. The stamens are longer, shorter or the same length as the anthers, are only hairy at the lower end and are fixed about 5 to 20 or 30 mm from the crown base. The pollen is medium-sized with a diameter of 24 to 38 µm, the pollen grain wall ( exine ) is thick or thin, mostly scaly or wrinkled around the pollen equator. Only in the species M. lopezii do the pollen grains have small spines, Ubisch bodies are known from only six species.

The mostly pear-shaped ovary is bilobed and two-chambered. The nectaries are well developed. The stigma is saddle-shaped or has two short branches.

fruit

Armando Hunziker regards the fruits as capsules , probably because the pericarp is thin and transparent and appears dry with age. Sandra Knapp describes the fruits as berries , but the lack of a thick pericarp speaks against this. The fruits are in an enlarging calyx, which is usually larger than the fruits, only in M. coccinea the fruit and calyx are almost the same length. The fruits have a long or short beak at the tip. The pericarp is only thick and leathery in M. crosbyana , in the other species it is thin and membrane-like. The fruits contain about 50 to 100 seeds , these are boomerang-shaped, or slightly curved to almost straight and rod-shaped. Their length ranges from 1.9 to 3.8 mm. The embryo is 1.6 to 3.2 mm long and slightly curved. It has attached cotyledons that are longer than wide and shorter, but wider than the rest of the embryo. Endosperm is very scarce.

ecology

Some of the species such as Markea longiflora , Markea formicarum , Markea ulei and Markea panamensis are closely related to colonies of the ant species Camponotus femuratus or species of the genus Atzeca ( myrmecophilia ). These Markea species have, among other things, swollen, bulbous stems that the ants use as nests or as storage space. On seeds of the species Markea coccinea there is a fine network of sticky threads on the seed surface, which may represent an adaptation to the seed dispersal by ants.

Bats are suspected to be pollinators of some species , since experiments in the Markea field have shown pollen on captured bats. In contrast to other New World plant species that are pollinated by bats, the morphology of the Markea flowers does not provide a way to directly reach the nectar while the bat hovers in front of the plant. It is believed that the animals crawl into the flower to get the nectar, but this could not be confirmed by observation. However, other forms of pollination also occur, for example Markea coccinea is adapted to pollination by birds ( ornithophilia ).

Predators are the caterpillars of various noble butterflies , which, in addition to Markea species, have specialized in plants of the nightshade genus Solandra , Schultesianthus , Juanulloa and Merinthopodium . These include species from the genera Olyras , Eutresis and Melinaea .

Occurrence

The main distribution area of ​​the genus is northern South America, where most species of the genus occur. They grow there in mountainous regions at altitudes between 500 and 3000 m, around ten of the species characterize the vegetation of the Andes of Colombia , Ecuador , Peru and Bolivia . Three species are endemic to Central America , four myrmecophilic species occur in the Amazon basin and Guyana .

Systematics

The delimitation of the genus Markea from other genera is currently still controversial. Above all, it is unclear how the relationships with the genera Hawkesiophyton and Schultesianthus are shaped. Sandra Knapp divided the species of the genus Hawkesiophyton into the genus Markea in a phylogenetic study from 1997 , but also recognized Schultesianthus as an independent genus. Armando Hunziker (2001), on the other hand, maintains the genus status of all three genera; he names the position of the anthers in the flowers as a distinguishing feature between the genera Hawkesiophyton and Markea . In molecular biological studies, only Markea ulei and Markea panamensis have so far been investigated; according to Hunziker, both belong to the genus Hawkesiophyton .

In the genus Markea , 11 to 20 species are recognized, depending on the author. The type species is Markea coccinea .

Currently recognized species:

Moved by Knapp to the genus Schultesianthus , but not recognized by Hunziker and continued as a Markea :

  • Markea crosybana D'Arcy ( syn.Schultesianthus crosbianus (D'Arcy) S. Knapp )
  • Markea uniflora Lundell ( syn.Schultesianthus uniflorus (Lundell) S. Knapp )
  • Markea venosa Standl. et CV Morton (syn. Schultesianthus venosus (Standl. et CV Morton) S. Knapp )

Inserted into the genus Markea by Knapp , listed as Hawkesiophyton by Hunziker :

  • Markea panamensis Standl. (syn. Hawkesiophyton panamensis (Standl.) Hunz. )
  • Markea ulei (Dammer) Cuatrec. (syn. Hawkesiophyton ulei (Dammer) Hunz. )
  • Hawkesiophyton klugii Hunz. (Synonymous with Markea ulei by Knapp )

proof

Main sources

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

Individual evidence

  1. ↑ a b c d e f João Renato Stehmann and Leandro Lacerda Giacomin: Markea atlantica (Solanaceae): a New Species of Tribe Juanulloeae Disjunct from its Core Distribution. In: Systematic Botany , Volume 37, Number 4, 2012. pp. 1035-1042. doi : 10.1600 / 036364412X656581
  2. ↑ a b c d e Andrés Orejuela, Clara Ines Orozco and Gloria Barboza: Three new species of Markea (Solanaceae, Juanulloeae) from Colombia. In: Phytotaxa , Volume 167, Numer 2, 2014. pp. 151-165.
  3. ↑ Nathan Muchhala and Pablu Jarrín-V .: Flower visitation by Bats in Cloud Forests of Western Ecuador. In: Biotropica , Volume 34, Number 3, 2002. pp. 387-395.
  4. ↑ a b Sandra Knapp, Viveca Persson and Stephen Blackmore: A Phylogenetic Conspectus of The Tribe Juanulloeae (Solanaceae). In: Annals of the Missouri Botanical Garden , Volume 84, 1997. pp. 67-89.
  5. ^ Richard Olmstead et al .: A molecular phylogeny of Solanaceae . In: Taxon , Volume 57, 2008. pp. 1159-1181.
  6. ↑ a b c Sandra Knapp: New Species and Notes on the Natural History of Markea (Solanacea) from Colombia and Ecuador. In: Novon , Volume 8, 1998. pp. 152-161.
  7. ↑ Eric F. Rodríguez Rodríguez: Una nueva especie de Markea (Solanaceae: Juanulloeae) para el Perú. In: Arnaldoa , Volume 13, Number 2, 2006. pp. 306-313. - Online ( Memento of the original from July 14, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / revistas.concytec.gob.pe