Homoranthus

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Homoranthus
Homoranthus flavescens

Homoranthus flavescens

Systematics
Eurosiden II
Order : Myrtle-like (Myrtales)
Family : Myrtle family (Myrtaceae)
Subfamily : Myrtoideae
Tribe : Chamelaucieae
Genre : Homoranthus
Scientific name
Homoranthus
A. Cunn. ex showers

Homoranthus is a genus of plants withinthe myrtle family (Myrtaceae). All about 31 species are originally found only in Australia .

description

Appearance and leaves

Homoranthus species grow as evergreen shrubs .

The opposite or decussate arranged on the branches leaves are often narrowed laterally so that the leaf blades thicker than they are wide, in the side view, they are linear, cylindrical to more or less upside down-lanceolate.

Inflorescences, flowers and fruits

In the upper leaf axils of undifferentiated branches there are reduced, capiform inflorescences that contain one to four flowers. Each flower stands over a pair of bracts , which are quickly perishable or remain during the anthesis (as long as the flower is open).

The hermaphroditic flowers are radial symmetry and five-fold with a double flower envelope . The flower cup (hypanthium) extends above the ovary and is usually five-ribbed. The sepals are completely fused or end in two to twelve slender fringed calyx lobes. The colors of the flowers are white or yellow to orange to red. The stamens are usually straight in the bud or rarely curved a few inward. Usually in one or two, rarely several circles, five or six more or less identical stamens are arranged. Ten fertile stamens alternate with ten staminodes . The spherical anthers open at the top with pores. Two carpels are a half under constant, single-chamber ovary grown. Two or ten anatropic ovules are arranged in basal placentation . The stylus, which protrudes conspicuously far from the flower envelope, has a ring of hairs below the scar.

The dry closing fruits are mostly single-seeded, rarely two-seeded nut fruits . The fruit is surrounded by the slightly enlarged flower cup.

Chromosome number

The chromosome numbers are 2n = 14, 16, 18 or 20, depending on the species.

Spread and endangerment

The genus Homoranthus is distributed with around 31 species on the southern and eastern Australian mainland. The species occur in the states of Queensland , New South Wales and South Australia .

Homoranthus darwinioides , Homoranthus decumbens , Homoranthus lunatus , Homoranthus montanus , Homoranthus porteri and Homoranthus prolixus are classified as "Vulnerable" = "at risk". No other species is considered threatened.

Systematics

Branch with leaves and flowers with the strikingly protruding pistils of Homoranthus darwinioides
Branch with leaves and flowers with the strikingly protruding pistils of Homoranthus papillatus
Homoranthus prolixus
Homoranthus tropicus
Homoranthus zeteticorum

The name Homoranthus comes from Allan Cunningham . The valid first publication of the genus homoranthus was in 1836 by Johannes Conrad Schauer in Article Genera Chamaelauciearum Nova Quaedam in Linnaea , vol 10, p 310. As Lectotypusart was homoranthus virgatus A.Cunn. ex shower set. The genus name Homoranthus is derived from the Greek words homoros for “to be adjacent” or “to border” and anthos for “flower”, this refers to the similarity of the flowers of closely related genera such as Darwinia . The current revision of the genus Homoranthus comes from Lachlan M. Copeland, Lyn A. Craven & Jeremy J. Bruhl: A taxonomic review of Homoranthus (Myrtaceae: Chamelaucieae) , In: Australian Systematic Botany , Volume 24, Issue 6, 2011, p. 351-374.

Synonyms for Homoranthus A.Cunn. ex showers are: Darwinia sect. Homoranthus (A.Cunn. Ex Schauer) Kuntze , Rylstonea R.T.Baker , Chamelaucium sect. Schuermannia F. Muell. , Darwinia sect. Schuermannia (F.Muell.) Benth. , Schuermannia F. Muell. , Chamaelaucium sect. Schnermannia F. Muell. orth. var.

The genus Homoranthus belongs to the tribe Chamelaucieae in the subfamily Myrtoideae within the family Myrtaceae .

There are around 31 species of Homoranthus (as of 2011); here with information on distribution:

use

Homoranthus flavescens is used as an ornamental plant in subtropical parks and gardens.

swell

Individual evidence

  1. ↑ a b c d e f g h GJ Harden: Entry in the New South Wales Flora Online . last accessed on January 18, 2013
  2. ^ A b c Lachlan M. Copeland, Lyn A. Craven & Jeremy J. Bruhl: A taxonomic review of Homoranthus (Myrtaceae: Chamelaucieae) , In: Australian Systematic Botany , Volume 24, Issue 6, December 21, 2011, p. 351 -374. doi : 10.1071 / SB11015
  3. ↑ EPBC Act List of Threatened Flora . last accessed on January 18, 2013
  4. ↑ First publication scanned at biodiversitylibrary.org .
  5. ↑ Entry in Tropicos . last accessed on January 18, 2013
  6. ↑ a b Entry in Australian Plant Name Index = APNI. last accessed on January 18, 2013
  7. ^ A b Thryptomene in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. last accessed on January 18, 2013
  8. ↑ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af Rafaël Govaerts (Ed.): Homoranthus. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved January 18, 2013.
  9. ↑ Gordon Cheers (Ed.): Botanica. The ABC of plants. 10,000 species in text and images . Könemann Verlagsgesellschaft, 2003, ISBN 3-8331-1600-5 (therein page 449).

Web links

Commons : Homoranthus  - collection of images, videos and audio files