Philcoxia | |
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Scientific classification ![]() | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Lamiales |
Family: | Plantaginaceae |
Tribe: | Gratioleae |
Genus: | Philcoxia P.Taylor & V.C.Souza |
Species | |
Philcoxia bahiensis Contents |
Philcoxia is a genus of seven rare plant species in the Plantaginaceae that are endemic to Brazil and resemble terrestrial species of the genus Utricularia . The genus, formally described in 2000, consists of the species P. bahiensis , P. goiasensis , P. minensis , P. tuberosa , P. rhizomatosa , P. maranhensis and P. courensis , each of the first three named for the Brazilian state to which it is endemic. The species are characterized by subterranean stems, peltate leaves at or below the soil surface, and five-lobed calyces. Their habitat has been reported as areas of white sand in the midst of cerrado vegetation at an elevation between 800 and 1450 m. Initial descriptions of the genus included suspicions that the plethora of stalked capitate glands on the upper surfaces of leaves was an indication that these species may be carnivorous. A study published in 2007 tested P. minensis for protease activity, a typical test for the carnivorous syndrome, and could detect none. Later studies detected other digestive enzymes such as phosphatases and qualitatively assessed prey digestion and nutrient uptake, suggesting that it is a true carnivorous plant. The genus epithet honors David Philcox (1926-2003), a botanist at Kew Gardens who worked extensively in tropical Scrophulariaceae. [4] [5]
Members of the genus are small perennial or annual herbs that reside in oases of deep white sand surrounded by the typical vegetation of the cerrado ecoregion. They are no more than 26 cm tall with 5-10 leaves. Zigzag-shaped racemes are produced from upright stems and account for the height of the species. These monotelic inflorescences are leafless and produce pale blue to lilac flowers (P. goiasensis has a yellow corolla tube). The flowers possess monothecous, glabrous anthers, which are unusual in the family. The upper surface of the leaves are covered with stalked capitate glands that are also seen in many carnivorous plant genera. [4] [5]
The nature of Philcoxia's highly specialized morphology has led to confusion about its proper taxonomic placement. In 1996, before Philcoxia was even formally published as a taxon, it had been placed by Vinícius Souza in the tribe Scrophularieae of the Scrophulariaceae. Peter Taylor et al. later noted in the 2000 description of the genus that its affinities should include the genera Gratiola and Dopatrium in the tribe Gratioleae of the Scrophulariaceae. The Angiosperm Phylogeny Group later changed the circumscription of the Scrophulariaceae so that the tribe Gratioleae is now within the Plantaginaceae. In 2004, E. Fischer also placed in tribe Gratioleae, but also placed it within the informally recognized subtribe Dopatriinae, which was described as also containing the genera Deinostema , Dopatrium , Hydrotriche , and Limnophila , which consist mostly of aquatic species. In 2007, an extensive study and phylogenetic analysis by Peter Fritsch et al. confirmed that Philcoxia should be placed in the tribe Gratioleae, but it is in fact not as closely related to Gratiola and the Dopatriinae as was previously assumed. [4] Recent research has suggested that P. minensis may be polyphyletic, so may represent more than one species. [6]
The first recognized specimens of Philcoxia (P. bahiensis) were collected by local resident Wilson Ganev in August 1992 from the Serra do Atalho in the municipality of Piatã of Bahia. One collection was sent to Kew Gardens for naming. Because of its placentation, the specimen was determined to be a member of the Scrophulariaceae (later Plantaginaceae sensu APG II) despite its appearance close to that of terrestrial Utricularia . Material of this specimen had been sent to Vinícius Souza, who was working on the Scrophulariaceae of Brazil. Souza recognized the material as congeneric with a plant collected in 1981 from the Serra do Cabral of the Brazilian state Minas Gerais. The collection was made by a group from the University of São Paulo. The site location of that collection was not identified and subsequent expeditions were unable to relocate the species until 2007. [5]
However, an even earlier specimen now recognized as P. goiasensis had been collected in 1966 near Posse in the northeastern state of Goiás by a group from the New York Botanical Garden. Initially, the specimen had been determined to be a member of the Lentibulariaceae. Peter Taylor and David Philcox later concluded that this represented an undescribed genus of Scrophulariaceae. A description and illustration was completed and set aside for over twenty years. Then, in 1994, Taylor showed the specimen and description to Ray Harley in preparation for publication. Harley, who had been involved in the early 1990s discovery of P. bahiensis, recognized Taylor's materials as another species of the as yet undescribed genus. [5]
Peter Taylor, in his 2000 description of the genus, suggested that the morphology of Philcoxia resembles that of the carnivorous Lentibulariaceae and the relatively unrelated Droseraceae in some aspects. The upper surface of the leaves are covered in stalked capitate glands similar to those seen in other carnivorous plants. Taylor noted that field observations had not indicated that there was any carnivorous function of the leaves, citing a lack of captured prey as evidence. [4] [5]
Peter Fritsch and his coauthors decided to do a more comprehensive test for carnivory on P. minensis after they observed nematode worms on leaf surfaces. The similarity between the habitat for Philcoxia species and that of Genlisea and their similar subterranean leaves and stems spurred the team's decision to test for potential carnivory in the field and in situ. They tested for a protease enzyme that is one of the enzymes found in other carnivorous plants and is responsible for breaking down captured prey. They hypothesized that Philcoxia could be carnivorous, capturing nematodes and possibly soil microbes like Utricularia and Genlisea do. Ultimately, Fritsch's study concluded that while no protease activity was detected, this fact does not rule out the possibility that the genus may be carnivorous in some other way. They note that there are many possibilities, such as seasonal carnivory or the unusual growth form being an adaptation to the heat and sun, and more study is needed before precise conclusions can be reached. [4] [5]
A study by Caio G. Pereira et al. published in 2012 provided experimental evidence using 15N-labeled nematodes, concluding that P. minensis actively digests prey and absorbs the nutrients. This data was combined with the observation that the leaf surfaces of P. minensis produce phosphatases, similar to many other carnivorous plants. [7] The similarity in structures in all the species of this genus suggest that all species are carnivorous. [6]
Plantaginaceae, the plantain family, is a large, diverse family of flowering plants in the order Lamiales that includes common flowers such as snapdragon and foxglove. It is unrelated to the banana-like fruit also called "plantain." In older classifications, Plantaginaceae was the only family of the order Plantaginales, but numerous phylogenetic studies, summarized by the Angiosperm Phylogeny Group, have demonstrated that this taxon should be included within Lamiales.
Lentibulariaceae is a family of carnivorous plants containing three genera: Genlisea, the corkscrew plants; Pinguicula, the butterworts; and Utricularia, the bladderworts.
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species. They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica. Utricularia are cultivated for their flowers, which are often compared with those of snapdragons and orchids, especially amongst carnivorous plant enthusiasts.
Genlisea is a genus of carnivorous plants also known as corkscrew plants. The 30 or so species grow in wet terrestrial to semi-aquatic environments distributed throughout Africa and Central and South America. The plants use highly modified underground leaves to attract, trap and digest minute microfauna, particularly protozoans. Although suggested a century earlier by Charles Darwin, carnivory in the genus was not proven until 1998.
Genlisea aurea is one of the largest carnivorous species in the genus Genlisea. It has pale bundles of root-like organs up to about 15 cm long under ground that attract, trap, and digest protozoans. These organs are subterranean leaves, which lack chlorophyll. G. aurea is endemic to Brazil, where it grows with several other species of Genlisea. It possesses an exceptionally small genome for a flowering plant.
A protocarnivorous plant, according to some definitions, traps and kills insects or other animals but lacks the ability to either directly digest or absorb nutrients from its prey like a carnivorous plant. The morphological adaptations such as sticky trichomes or pitfall traps of protocarnivorous plants parallel the trap structures of confirmed carnivorous plants.
Utricularia resupinata, popularly known as lavender bladderwort or northeastern bladderwort, is a small perennial subaquatic carnivorous plant that belongs to the genus Utricularia. It is native to eastern Canada, the United States, and Central America. This plant species has an interesting etymology, growth pattern, ecology, and research history. As a plant that is threatened or endangered in many of the States where it is found, it is a candidate for sound conservation efforts.
Philcoxia bahiensis is a rare plant species in the Plantaginaceae that is endemic to the Brazilian state of Bahia. It was first discovered collected by a local resident, Wilson Ganev, in August 1992 from the Serra do Atalho in the Piatã municipality. That collection was sent to Kew Gardens for naming. Because of its placentation, the specimen was determined to be a member of the Scrophulariaceae despite its appearance close to that of terrestrial Utricularia. Material of this specimen had been sent to Vinícius Souza, who was working on the Scrophulariaceae of Brazil. It was then formally described in 2000 as a new species.
Colura zoophaga is a species of epiphytic liverwort that is endemic to the African highlands, specifically parts of Kenya. It belongs to the genus Colura, which has been hypothesized to be carnivorous as early as 1893. It is a recently described species that was the subject of the first scientific study aimed at investigating the allegations of carnivory in liverworts.
Utricularia purpurea, the eastern purple bladderwort, is a medium-sized suspended aquatic carnivorous plant that belongs to the genus Utricularia. U. purpurea is endemic to North and Central America. It has been suggested that U. purpurea may have partially lost its appetite for carnivory. Richards (2001) did an extensive study in the field on it and noted that trapping rates of the usual Utricularia prey were significantly lower than in other species in the genus. Richards concludes that this species can still trap and digest arthropod prey in its specialized bladder traps, but does so sparingly. Instead, it harbors a community of algae, zooplankton, and debris in the bladders that indicates U. purpurea favors a mutualistic interaction in place of a predator–prey relationship.
Utricularia calycifida is a small to medium-sized terrestrial perennial carnivorous plant that belongs to the genus Utricularia. U. calycifida is endemic to northern South America and can be found in Brazil, Guyana, Suriname, and Venezuela.
Peter Geoffrey Taylor (1926–2011) was a British botanist who worked at Royal Botanic Gardens, Kew throughout his career in botany. Taylor was born in 1926 and joined the staff of the herbarium at Kew in 1948. He published his first new species, Utricularia pentadactyla, in 1954. In 1973, Taylor was appointed curator of the orchid division of the herbarium and, according to Kew, "under his direction, orchid taxonomy was revitalised and its horticultural contacts strengthened."
Utricularia sandersonii, Sanderson's bladderwort, is a species of flowering plant in the bladderwort family. Originally described and published by the British botanist Daniel Oliver in 1865, it is a carnivorous evergreen perennial, endemic to northern KwaZulu-Natal and Transkei in South Africa.
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods, and occasionally small mammals and birds. They still generate all of their energy from photosynthesis. They have adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic bogs. They can be found on all continents except Antarctica, as well as many Pacific islands. In 1875, Charles Darwin published Insectivorous Plants, the first treatise to recognize the significance of carnivory in plants, describing years of painstaking research.
The Genus Utricularia: A Taxonomic Monograph is a monograph by Peter Taylor on the carnivorous plant genus Utricularia, the bladderworts. It was published in 1989 by Her Majesty's Stationery Office (HMSO) as the fourteenth entry in the Kew Bulletin Additional Series. It was reprinted for The Royal Botanic Gardens, Kew in 1994.
Philcoxia minensis is a rare annual herb of the family Plantaginaceae, that is endemic to the Serra do Cabral area of the Brazilian state Minas Gerais. It was discovered April 17, 1981 by David philcox. in the municipality of Joaquim Felício and grew near other plants from the campos rupestres montane savanna. The exact location of collection was unspecified. The species has been shown to produce phosphatases.
Philcoxia goiasensis is a rare annual herb in the family Plantaginaceae and is endemic to the Rio da Prata area of Posse, Goiás, in Brazil.
Matourea is a genus in the family Plantaginaceae. It is found in South America. It is the correct name for former genus Achetaria that contained ten species.
Psyllocarpus is a genus of flowering plants belonging to the family Rubiaceae. It is an endemic genus of Brazil found in Amazonia, Caatinga, and Cerrado. In 1979 the genus was revised by Kirkbride into two sections, Psyllocarpus sect. Psyllocarpus and P. sect Amazonica, based on geographic distribution and morphology. Plants of the World Online treats the genus as a synonym of Tapanhuacanga.