All articles starting with R
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Rhinotermitidae
Rhinotermitidae, the subterranean termites (Froggatt, 1897), is a paraphyletic termite family in Blattodea including pest genera Coptotermes, Reticulitermes, and Heterotermes; lower termites with hindgut flagellate symbionts, oldest fossil Archeorhinotermes at 98 Ma.
Rhinovirus
Rhinoviruses (RV-A, RV-B, RV-C), picornaviruses of the Enterovirus genus, are the most frequent cause of the common cold and major asthma triggers; no vaccine or antiviral therapy exists.
Rhio
Rhio is an English professional wrestler from Preston known for power wrestling across UK indies; record PROGRESS Women's title reign (400+ days), two-time champion, ICW World Heavyweight Champion, #25 on the 2024 PWI Women's 250. Distinct from Japanese wrestler Riho.
Rhion
Rhion (Ῥίον, Rhium) was an Achaean promontory at the western entrance of the Corinthian Gulf, opposite Antirrhium, with a temple of Poseidon; defended by Phormio in 431-421 BC, now modern Río, Greece.
Rhipicephalus
Rhipicephalus (brown ticks), genus Koch 1844 of hard ticks, ~90 species, African origin; includes brown dog tick R. sanguineus and cattle fever ticks R. (Boophilus) annulatus and microplus, vectors of spotted fevers and bovine babesiosis.
Rhipidomys
Rhipidomys (South American climbing mice and rats, ratos arborícolas) is a genus of 25 arboreal cricetid rodents in tribe Thomasomyini, ranging from eastern Panama to northern Argentina, with head-body length under 90 mm to over 210 mm.
Rhipidura
Rhipidura (fantails) is a genus of small insectivorous passerine birds in Rhipiduridae, erected by Vigors and Horsfield in 1827; about 48 species across Asia, Australasia, and the Pacific, named for tail-fanning foraging behavior.
Rhipsalis
Rhipsalis, the mistletoe cacti, is a genus of about 45 species of spineless epiphytic cacti native to tropical America, with R. baccifera reaching Africa and Sri Lanka.
Rhizaria
Rhizaria (Cavalier-Smith 2002) is a eukaryote supergroup of amoeboid protists with filose or reticulose pseudopodia, comprising Cercozoa and Retaria (Foraminifera, Radiolaria), part of the SAR clade, important in marine carbon and silicon cycling.
Rhizobia
Rhizobia are soil bacteria, including Rhizobium, Bradyrhizobium, and Sinorhizobium, that fix atmospheric nitrogen in root nodules of legumes via flavonoid-NodD-Nod factor signaling, distinguishing them from free-living nitrogen fixers.
Rhizobiaceae
Rhizobiaceae: family of gram-negative Alphaproteobacteria (Hyphomicrobiales), proposed 1938, with 276+ species in 38 genera; includes nitrogen-fixing rhizobia (Rhizobium, Ensifer), tumor-forming Agrobacterium, and Liberibacter; genera delimited by ~86% cpAAI.
Rhizobium
Rhizobium, a genus of soil Alphaproteobacteria in the Rhizobiaceae, forms nitrogen-fixing root nodule symbioses with legumes; rhizobia include Bradyrhizobium, Sinorhizobium, and Mesorhizobium, and are widely used as legume inoculants.
Rhizobium leguminosarum
Rhizobium leguminosarum, named by Frank in 1889, is a Gram-negative soil bacterium fixing nitrogen in legume root nodules; biovars viciae, trifolii, and phaseoli nodulate pea, clover, and bean, within a species complex of 18 genospecies.
Rhizocarpon
Rhizocarpon, map lichen genus (R. geographicum), crustose lichenized fungi on siliceous rock, ca 150 species, key tool of lichenometric dating; paraphyletic, revised into five genera in 2025.
Rhizocephala
Rhizocephala, parasitic barnacles (Cirripedia), 250–300 species infecting crabs and hermit crabs; adults reduced to interna rootlets and externa sac, with kentrogonid or akentrogonid life cycles and 13 monophyletic families after 2020 revision.
Rhizoctonia
Rhizoctonia (DC. 1805) is a genus of soil-borne basidiomycete fungi, also historically split as Thanatephorus and Ceratobasidium, defined by non-sporing mycelium, sclerotia, and dolipore septa. Its best-known species, R. solani, is an anastomosis-grouped species complex infecting over 200 crop species, causing damping-off, root rot, and sheath blight.
Rhizoid
Rhizoid: unicellular or multicellular root-like filament anchoring bryophytes and fern or clubmoss gametophytes, absorbing water and ions; unlike true roots, lacks vascular tissue, root cap, and endogenous branching.
Rhizome
Rhizome: a horizontally growing modified plant stem at or just below the soil surface, bearing buds and roots at nodes; examples include iris, bamboo, and ginger; distinct from bulbs, corms, tubers, and stolons.
Rhizome (philosophy)
Rhizome (philosophy): Deleuze and Guattari's concept of a lateral, decentered, nonhierarchical web of relations, opposed to the tree model; introduced in Kafka (1975) and Rhizome: Introduction (1976), expanded in A Thousand Plateaus (1980).
Rhizomelic chondrodysplasia punctata
Rhizomelic chondrodysplasia punctata (RCDP, RCDP1/PEX7-RCDP) is a rare autosomal recessive peroxisome biogenesis disorder causing rhizomelia, stippled cartilage calcifications, cataracts, and severe intellectual disability, with deficient plasmalogens and phytanic acid oxidation but normal VLCFA.
Rhizomnium dentatum
Rhizomnium dentatum is an extinct moss of the family Mniaceae, the first fossil species of the genus Rhizomnium, described in 2014 from five gametophyte fragments in Eocene Baltic amber and distinguished by shortly dentate leaf margins.
Rhizomucor
Rhizomucor, a genus of thermophilic Mucorales fungi (R. miehei, R. pusillus), grows above 50 °C, causes about 5% of mucormycosis cases, and yields industrial rennet and lipase enzymes.
Rhizon/Risinium
Rhizon (Greek Ῥίζων, Latin Risinium/Risinum), at modern Risan in Montenegro's Bay of Kotor, was an Illyrian royal stronghold where Queen Teuta took refuge in 229 BC, later the Roman municipium Risinium, god Medaurus, excavated by Warsaw since 2001.
Rhizophagus irregularis
Rhizophagus irregularis (formerly Glomus intraradices/G. irregulare) is a model arbuscular mycorrhizal fungus symbiotic with ~80% of plant species; strain DAOM197198 was the first AMF genome sequenced.
Rhizophora
Rhizophora is a genus of six accepted mangrove tree species in Rhizophoraceae, including the red mangrove R. mangle, defined by prop roots, over 90% root salt exclusion, and buoyant viviparous propagules that disperse by floating.
Rhizophora apiculata
Rhizophora apiculata (kongkang) is an Indo-West Pacific mangrove tree of Rhizophoraceae, dominant on estuarine mud from South Asia to Queensland, parent of two hybrids, used for charcoal and wood, IUCN Least Concern.
Rhizophora mangle
Rhizophora mangle, the red mangrove, is a viviparous stilt-rooted evergreen tree of tropical intertidal coasts of America and West Africa, tolerating 0-90 ppt salinity, IUCN Least Concern, invasive in Hawaii and Queensland.
Rhizophora mucronata
Rhizophora mucronata, Asiatic or loop-root mangrove (Rhizophoraceae), is a viviparous Indo-Pacific mangrove tree to 25 m with stilt roots and pointed leaves; bark yields tannin, parts serve traditional medicine, and it is IUCN Least Concern.
Rhizophoraceae
Rhizophoraceae, the red mangrove family, is a mainly Old World tropical family of 15–16 genera and about 145 species in Malpighiales, including about half of the world's true mangrove species.
Rhizopus
Rhizopus, a genus of fast-growing Mucorales molds with rhizoids and sporangia, includes bread mold R. stolonifer, tempeh culture R. oligosporus, and R. arrhizus (syn. R. oryzae), the leading cause of mucormycosis.