Apocynaceae (, from Apocynum, Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison.<!-- https://www.c82.net/twining/plants/?id=92 - "Elizabeth Twining's celebrated catalog of botanical illustrations from 1868, Illustrations of the Natural Orders of Plants" notes "in the time of Pliny" (not really a ref, but a starting point) --> and includes annual plants, perennial herbs, stem succulents, woody shrubs, trees, or vines.

Leaves and stems

Leaves are simple. They may appear one at a time (singly) with each occurrence on alternating sides of the stem, but usually occur in pairs (and rarely in whorls).]]

Flowers of the Apocynaceae are complex and highly derived. They are perfect (bisexual), with a synsepalous, five-lobed calyx united into a tube at the base. The pollen is transported in foam.

The fruit is a drupe, a berry, a capsule, or a (frequently paired) follicle.

Taxonomy

As of 2012, the family was described as comprising some 5,100 species, in five subfamilies:

  • Apocynoideae Burnett, 1835
  • Asclepiadoideae Burnett, 1835 (incorporating the Asclepiadaceae)
  • Periplocoideae Endl., 1838
  • Rauvolfioideae Kostel., 1834
  • Secamonoideae Endl., 1838

The former family Asclepiadaceae is included in Apocynaceae according to the Angiosperm Phylogeny Group III (APG III) modern, largely molecular-based system of flowering plant taxonomy.

An updated classification, including 366 genera, 25 tribes, and 49 subtribes, was published in 2014.

376 genera are currently accepted.

Distribution and habitat

Species in this family are distributed mainly in tropical regions:

  • In the tropical forests and swamps of Indomalaya: small to very tall evergreen trees up to tall, often with buttress roots, such as Alstonia and Dyera.
  • In Australia: occurs in all habitats; about 46 genera and about 200 species, including about 20 naturalised; herbs, vines, shrubs and trees.
  • In deciduous forests of Africa, India, and Indo-China: smaller trees such as Carissa, Wrightia, and Holarrhena
  • In tropical America, India, Myanmar, and Malaya: evergreen trees and shrubs, such as Rauvolfia, Tabernaemontana, and Acokanthera.
  • In Central America: Plumeria, or the frangipani, with its waxy white or pink flowers and a sweet scent.
  • In South America, Africa, and Madagascar: many lianas, such as Landolphia
  • In the Mediterranean region: Nerium, with the well-known oleander or be-still tree (Nerium oleander), and Apple of Sodom (Calotropis procera), with other (Calotropis) species extending into South Asia.
  • The only genera found in temperate Europe away from the Mediterranean are Vinca (Rauvolfioideae) and Vincetoxicum (Asclepiadoideae). Also Asclepias syriaca is an invasive weed (e. g., in many areas of Ukraine).
  • In North America: Apocynum, dogbane or Indian hemp, including Apocynum cannabinum, a traditional source of fiber. Also the bluestars, Amsonia, herbaceous perennials of upright habit, grown as ornamental plants for their attractive flowers.
  • In continental southern Africa (Angola, Botswana, Eswatini, Mozambique, South Africa, and Zimbabwe) and Madagascar, except for the humid evergreen forest of the eastern side of Madagascar, and never above for the entire island: Pachypodium and Fockea.

Ecology

Several genera are preferred larval host plants for the Queen Butterfly (Danaus gilippus).

Toxicity

Many species of plants from the family Apocynaceae have some toxicity, with some being extremely poisonous if parts are ingested, or if they are not handled properly. Genera containing cardiac glycosides—Cerbera, Nerium, Asclepias, Cascabela, Strophanthus, Apocynum, Thevetia, etc.—have therapeutic ranges, but are often associated with accidental poisonings, in many cases lethal (see below). Alkaloid-producing species like Rauvolfia serpentina, Catharanthus roseus, and Tabernanthe iboga are likewise the source of compounds with therapeutic ranges, but which have significant associated toxicities if not taken in appropriate doses and in controlled fashion. (See below)

Uses

Several members of the family Apocynaceae have had economic uses in the past. Several are sources of important natural products—pharmacologic tool compounds and drug research candidates, and in some cases actual prescription drugs. Cardiac glycosides, which affect heart function, are a ready example. Genera studied and known to contain such glycosides include Acokanthera, Apocynum, Cerbera, Nerium, Thevetia and Strophanthus. Rauvolfia serpentina (Indian snakeroot) contains the alkaloid reserpine, which has been used as an antihypertensive and an antipsychotic drug but its adverse effects limit its clinical use. Catharanthus roseus yields alkaloids used in the treatment of cancer. Tabernanthe iboga, Voacanga africana, and Tabernaemontana undulata contain the alkaloid ibogaine, which is a psychedelic drug which may help with drug addiction, but which has significant adverse effects, with ibogaine being both cardiotoxic and neurotoxic. Ajmalicine, an alkaloid found in Rauvolfia spp., Catharanthus roseus, and Mitragyna speciosa, is an antihypertensive drug used in the treatment of high blood pressure. Nerium (oleander), Vinca (periwinkle), Carissa (Natal plum), Allamanda (golden trumpet), Plumeria (frangipani), Thevetia, Mandevilla (Savannah flower), and Adenium (desert-rose).

In addition, the genera Landolphia, Carpodinus, and Mascarenhasia have been used as commercial sources of inferior rubber. (See Congo rubber)

There are limited dietary uses of plants from this family. The flower of Echites panduratus (common name: ') is edible. Carissa (Natal plum) produces an edible fruit, but all other parts of the plant are poisonous. The genus Apocynum was reportedly used as a source of fiber by Native Americans. The aromatic fruit juice from Saba comorensis (syn. Landolphia comorensis, the Bungo or Mbungo fruit) is used as a drink.

Finally, ethnopharmacologic and ethnotoxicologic uses are also known. The roots of Tabernanthe iboga and certain Voacanga species have traditionally been used ceremonially as hallucinogens in Africa. The ibogaine-type alkaloids responsible for the psychoactivity of these plants have been studied with regard to the treatment of drug addiction.

Many species are ornamental in gardens or as houseplants.

Flowers

<gallery>

File:Acokanthera oblongifolia 2445.JPG|Acokanthera oblongifolia

File:Adenium obesum3.jpg|Adenium obesum

File:Allamanda cathartica flowers 2.JPG|Allamanda cathartica

File:糖膠樹(黑板樹) Alstonia scholaris -香港中央圖書館 Hong Kong Central Library- (9237370435).jpg|Alstonia scholaris

File:Starr 030222-0002 Alyxia oliviformis.jpg|Alyxia oliviformis

File:Amsonia tabernaemontana kz01.jpg|Amsonia tabernaemontana

File:Ancylobothrys capensis08.jpg|Ancylobothrys capensis

File:Aspidosperma quebracho-blanco - Köhler–s Medizinal-Pflanzen-017.jpg|Aspidosperma quebracho-blanco illustration in Köhler's Medizinal-Pflanzen

File:Caralluma burchardii IMGP8282.JPG|Apteranthes burchardii

File:Asclepias curassavica 1854.jpg|Asclepias curassavica

File:Caralluma acutangula Bild0685.jpg|Caralluma acutangula

File:Caralluma europaea - cvet.jpg|Caralluma europaea

File:Caralluma socotrana 01.jpg|Caralluma socotrana

File:Cascabela thevetia1MTFL.jpg|Cascabela thevetia (syn. Thevetia peruviana)

File:Catharanthus roseus-IMG 5432.jpg|Catharanthus roseus

File:Cerbera manghas flower.jpg|Cerbera manghas

File:Cryptolepis buchananii (2618297906).jpg|Cryptolepis dubia

File:Cycladeniahumilisjonesii.JPG|Cycladenia humilis var.jonesii

File:Holarrhena pubescens flowers.jpg|Holarrhena pubescens

File:Hoodia gordonii 1DS-II 2-3327.jpg|Hoodia gordonii

File:Hoya FR 2013.jpg|Hoya carnosa

File:Mandevilla boliviensis.jpg|Mandevilla boliviensis

File:Nerium oleander pink.jpg|Nerium oleander

File:Ochrosia borbonica 02.JPG|Ochrosia borbonica

File:Pachypodium lamerei 5Dsr 1733.jpg|Pachypodium lamerei

File:Comarca Oeste, Las Palmas, Spain - panoramio.jpg|Pachypodium lamerei growth habit

File:Fiore di Periploca graeca.jpg|Periploca graeca

File:Plumeria rubra L. (2257161947).jpg|Plumeria rubra

File:Rhabdadenia madida.jpg|Rhabdadenia madida

File:Rauvolfia serpentina 11.JPG|Rauvolfia serpentina

File:Saba senegalensis 0002.jpg|Saba senegalensis

File:Secamone alpini00.jpg|Secamone alpini

File:Aasblume Aug 2005.jpg|Stapelia gigantea

File:Strophanthus speciosus 1DS-II 6026.jpg|Strophanthus speciosus

File:Tabernaemontana divaricata flower in jaffna.JPG|Tabernaemontana divaricata

File:Tabernanthe iboga MS 4098.jpg|Tabernanthe iboga in flower and fruit

File:(MAD) T. jasminoides-1.jpg|Trachelospermum jasminoides

File:Vinca minor beentree.jpg|Vinca minor

File:Wrightia tinctoria flowers in Keesaraguda, AP W IMG 9109.jpg|Wrightia tinctoria

File:Wrightia antidysenterica (2).JPG|Wrightia antidysenterica

File:Wrightia tinctoria 09.JPG|Wrightia tinctoria single flower

</gallery>

Fruits

<gallery>

File:Acokanthera oblongifolia 03.jpg|Acokanthera oblongifolia

File:Fruits in Adenuim Obesum Plant on Terrace garden.jpg|Adenium obesum

File:Adenium obesum pod and seeds.jpg|Adenium obesum dehiscence of single fruit.

File:Allamanda cathartica MHNT.jpg|Allamanda cathartica

File:Alstonia scholaris fruits.JPG|Alstonia scholaris

File:Alyxia oliviformis fruit.jpg|Alyxia oliviformis

File:Amsonia tabernaemontana container plant in fruit (paired follicles).jpg|Amsonia tabernaemontana containerised specimen in fruit

File:Amsonia tabernaemontana single paired follicle detached from plant (pale side).jpg|Amsonia tabernaemontana single paired follicle detached from plant (paler, unsunned side)

File:Ancylobothrys capensis, vrugte, Faerie Glen NR.jpg|Ancylobothrys capensis

File:Milkweed-in-seed.jpg|Asclepias syriaca dehiscent follicles (before unfurling of pappi)

File:Asclepias curassavica 003.JPG|Asclepias curassavica dehiscent follicles shedding seeds with unfurled pappi

File:Thevetia peruviana 04.JPG| Cascabela thevetia (syn.Thevetia peruviana)

File:Thevetia peruviana - Fruits.jpg| Cascabela thevetia (syn.Thevetia peruviana): dissection of toxic fruits.

File:Cerbera tanghin - Köhler–s Medizinal-Pflanzen-176.jpg|Cerbera manghas

File:Cryptolepis buchananii (6048993215).jpg|Cryptolepis dubia

File:Holarrhena pubescens fruits.jpg|Holarrhena pubescens

File:Hoodia gordonii Frucht P1010402.JPG|Hoodia gordoniI

File:Mandevilla boliviensis 9zz.jpg|Mandevilla boliviensis

File:Nerium oleander seeds.jpg|Nerium oleander (dehiscence)

File:Ochrosia borbonica fruit 1.JPG|Ochrosia borbonica

File:Pachypodium namaquanum 1DS-II 1-C5587.jpg|Pachypodium namaquanum

File:Periploca graeca Silk Vine ღვედკეცი.JPG|Periploca graeca

File:Plumeria alba (seed pods).jpg|Plumeria alba

File:സർപഗന്ധി വിത്തുകൾ 13.JPG|Rauvolfia serpentina

File:Saba senegalensis MS 1367.JPG|Saba senegalensis unripe fruit

File:Saba senegalensis - fruit pulp sections.jpg|Saba senegalensis: dissection of ripe, edible fruit

File:Secamone parvifolia 1DS-II 3-3506.jpg|Secamone parvifolia

File:Stapelia gigantea 1DS-II 8834.jpg|Stapelia gigantea

File:Strophanthus speciosus, vrugkapsule en sade, Manie van der Schijff BT, a.jpg| Strophanthus speciosus (dehiscence)

File:Tabernaemontana catharinensis (1).JPG|Tabernaemontana catharinensis (dehiscence)

File:Iboga.jpg|Tabernanthe iboga

File:Trachelospermum jasminoides fruits+seeds.jpg|Trachelospermum jasminoides (dehiscence)

File:Trachelospermum jasminoides seeds.jpg|Trachelospermum jasminoides: individual seeds, showing pappus

File:Vinca major vima 002 php.jpg|Vinca major (seeds)

File:Illustration Vinca minor0 clean.png|Vinca minor: botanical plate showing paired fruits (no. 5)

File:Wrightia tinctoria 32.JPG|Wrightia tinctoria

</gallery>

Pachycaul species

<gallery>File:Desert rose Adenium obesum in Tanzania 2259 Nevit.jpg|Adenium obesum growth habit of wild specimens, Tanzania

File:Desert Rose (Adenium obesum), Ghana.jpg|Adenium obesum close-up of colossal specimen, Ghana

File:Desert Rose, Socotra Is (17131661372).jpg|Adenium obesum trunk of extreme pachycaul specimen, Socotra

File:Pachypodium lamerei 01.jpg|Pachypodium lamerei wild specimen of maximum height (approx ) attained by species

File:Pachypodium lamieri1MTFL.jpg|Pachypodium lamerei in flower

File:PachypodiumLamerei.jpg|Pachypodium lamerei mature, multi-trunked specimen cultivated in glasshouse

File:Pachypodium namaquanum00.jpg|Pachypodium namaquanum</gallery>

References

  • Apocynaceae in BoDD – Botanical Dermatology Database

Further reading

  • A review on antimicrobial botanicals, phytochemicals and natural resistance modifying agents from Apocynaceae family: Possible therapeutic approaches against multidrug resistance in pathogenic microorganisms.