Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes.
Cuscuta, commonly known as dodder or amarbel, is a genus of over 201 species of yellow, orange, or red parasitic plants. Formerly treated as the only genus in the family Cuscutaceae, it now is accepted as belonging in the morning glory family, Convolvulaceae, on the basis of the work of the Angiosperm Phylogeny Group. The genus is found throughout the temperate and tropical regions of the world, with the greatest species diversity in subtropical and tropical regions; the genus becomes rare in cool temperate climates, with only four species native to northern Europe.
Loranthaceae, commonly known as the showy mistletoes, is a family of flowering plants. It consists of about 75 genera and 1,000 species of woody plants, many of them hemiparasites. The three terrestrial species are Nuytsia floribunda, Atkinsonia ligustrina, and Gaiadendron punctatum Loranthaceae are primarily xylem parasites, but their haustoria may sometimes tap the phloem, while Tristerix aphyllus is almost holoparasitic. For a more complete description of the Australian Loranthaceae, see Flora of Australia online., for the Malesian Loranthaceae see Flora of Malesia.
In evolutionary ecology, a parasitoid is an organism that lives in close association with its host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionary strategies within parasitism, distinguished by the fatal prognosis for the host, which makes the strategy close to predation.
In botany and mycology, a haustorium is a rootlike structure that grows into or around another structure to absorb water or nutrients. For example, in mistletoe or members of the broomrape family, the structure penetrates the host's tissue and draws nutrients from it. In mycology, it refers to the appendage or portion of a parasitic fungus, which performs a similar function. Microscopic haustoria penetrate the host plant's cell wall and siphon nutrients from the space between the cell wall and plasma membrane but do not penetrate the membrane itself. Larger haustoria do this at the tissue level.
Orobanchaceae, the broomrapes, is a family of mostly parasitic plants of the order Lamiales, with about 90 genera and more than 2000 species. Many of these genera were formerly included in the family Scrophulariaceae sensu lato. With its new circumscription, Orobanchaceae forms a distinct, monophyletic family. From a phylogenetic perspective, it is defined as the largest crown clade containing Orobanche major and relatives, but neither Paulownia tomentosa nor Phryma leptostachya nor Mazus japonicus.
Cassytha is a genus of some two dozen species of obligately parasitic vines in the family Lauraceae. Superficially, and in some aspects of their ecology, they closely resemble plants in the unrelated genus Cuscuta, the dodders. When fruit and flowers are absent in the field, the physical resemblance is so close that few people without technical training can discern the difference. In this respect and in their ecology the two genera present a spectacular example of convergent evolution. Nonetheless, Nickrent comments that "Cassytha is uneqivocally assigned to Lauraceae based on (both) morphological and molecular data." In its divergence from habits typical of the Lauraceae, Cassytha also presents examples of mosaic evolution
Parasitoid wasps are a large group of hymenopteran superfamilies, with all but the wood wasps (Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, sooner or later causing the death of these hosts. Different species specialise in hosts from different insect orders, most often Lepidoptera, though some select beetles, flies, or bugs; the spider wasps (Pompilidae) exclusively attack spiders. More rarely, parasitoid wasps may use plant seeds as hosts, such as Torymus druparum.
Schoepfia is a genus of small hemiparasitic trees, flowering plants belonging to the family Schoepfiaceae. The genus has long been placed in the Olacaceae family.
The Eucharitidae are a family of parasitic wasps. Eucharitid wasps are members of the superfamily Chalcidoidea and consist of three subfamilies: Oraseminae, Eucharitinae, and Gollumiellinae. Most of the 55 genera and 417 species of Eucharitidae are members of the subfamilies Oraseminae and Eucharitinae, and are found in tropical regions of the world.
A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called the haustorium, which penetrates the host plant, connecting them to the host vasculature – either the xylem, phloem, or both. For example, plants like Striga or Rhinanthus connect only to the xylem, via xylem bridges (xylem-feeding). Alternately, plants like Cuscuta and some members of Orobanche connect to both the xylem and phloem of the host. This provides them with the ability to extract resources from the host. These resources can include water, nitrogen, carbon and/or sugars Parasitic plants are classified depending on the location where the parasitic plant latches onto the host, the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given off by host shoots or roots, respectively. About 4,500 species of parasitic plants in approximately 20 families of flowering plants are known.
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of the clade Aculeata can sting their prey.
Cassytha melantha is a parasitic vine. Common names include coarse dodder-laurel and large dodder-laurel. The fruits are about 10–15 millimetres (0.39–0.59 in) in diameter and are green, drying to black. These are edible and are harvested in the wild.
Parabiosis is a laboratory technique used in physiological research, derived from the Greek word meaning "living beside." The technique involves the surgical joining of two living organisms in such a way that they develop a single, shared physiological system. Through this unique approach, researchers can study the exchange of blood, hormones, and other substances between the two organisms, allowing for the examination of a wide range of physiological phenomena and interactions. Parabiosis has been employed in various fields of study, including stem cell research, endocrinology, aging research, and immunology.
Cassytha pubescens is a native Australian hemiparasitic vine species, in the Laurel family. Common names for the species include devils twine, dodder-laurel, spilled devil's twine, snotty gobble or downy dodder-laurel. It is a widespread and common species in south eastern Australia. The species was first formally described in 1810 by the Scottish botanist Robert Brown in Prodromus Flora Novae Hollandiae et Insulae Van Diemen. Leaves are reduced to scales and photosynthesis is achieved through chlorophyll contained in the plants stems. Stems are between 0.5mm and 1.5mm in diameter and the haustoria are between 2 and 3 mm long.
Cassytha glabella, commonly known as the slender devil's twine, is a common twining plant of the Laurel family, found in many of the moister parts of Australia. A hemi-parasitic climber. The specific epithet glabella is from Latin, referring to the lack of hairs. The fruit are sweet and mucousy to taste. The Devil's Twine and Cassytha melantha are similar, but with thicker hairier stems.
Cuscuta pacifica is a species of dodder. Its common name is goldenthread.
Cuscuta sandwichiana is a parasitic vine and the only member of the genus Cuscuta that is endemic to the Hawaiian Islands. It parasitizes a wide variety of indigenous, endemic and introduced plants on all of the main Hawaiian islands. It grows in coastal areas with sandy soils from sea level elevation to 975 feet. The indigenous kaunaʻoa pehu Cassytha filiformis is a similar looking species with the same parasitic nature. It is an unrelated plant in the Laurel family Lauraceae which can be distinguished by it larger, coarser yellowish-green stems.
Cuscuta compacta, the compact dodder, is a parasitic plant that specializes on woody plants. This species is distributed across the Eastern and Midwestern USA, Eastern Canada, and Mexico.
Cuscuta gronovii is a yellow vine that grows as a parasite off other plants. It is a dicot.
