Monotropaceae was a small family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of flowering plant

Flowering plant

The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...

s under the old Cronquist system

Cronquist system

The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in his texts An Integrated System of Classification of Flowering Plants and The Evolution and Classification of Flowering Plants .Cronquist's system places flowering plants into two...

 of plant classification. It included 10 genera

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Allotropa, Cheilotheca

Cheilotheca

Cheilotheca is a small genus of myco-heterotrophic plants in the heath family . As currently circumscribed the group includes three species.-Etymology:...

, Hemitomes

Hemitomes

Hemitomes is a monotypic genus of plants containing the single species Hemitomes congestum, which is known as gnome plant and cone plant. This rare and unusual plant is native to the west coast of North America from British Columbia to California, where it grows in dense, dark forests such as the...

, Monotropa

Monotropa

Monotropa is a genus of two species of herbaceous perennial plants, formerly classified in the family Monotropaceae, but now included within the Ericaceae...

, Monotropastrum

Monotropastrum

Monotropastrum is a small genus of myco-heterotrophic plants in the heath family . As currently circumscribed the group includes two species.-Distribution:...

, Monotropsis, Pityopus

Pityopus

Pityopus is a monotypic genus of flowering plants in the heath family containing the single species Pityopus californica, which is known by the common name pinefoot. It is native to the mountains of the west coast of the United States from Washington to California, where it grows in coniferous and...

, Pleuricospora

Pleuricospora

Pleuricospora is a monotypic genus of flowering plants in the heath family containing the single species Pleuricospora fimbriolata, which is known by the common name fringed pinesap. It is native to the forests of the west coast of North America from British Columbia to the San Francisco Bay Area...

, Pterospora, Sarcodes.

Recent genetic research by the Angiosperm Phylogeny Group

Angiosperm Phylogeny Group

The Angiosperm Phylogeny Group, or APG, refers to an informal international group of systematic botanists who came together to try to establish a consensus on the taxonomy of flowering plants that would reflect new knowledge about plant relationships discovered through phylogenetic studies., three...

 has however demonstrated that these genera are better placed in the blueberry family, the Ericaceae

Ericaceae

The Ericaceae, commonly known as the heath or heather family, is a group of mostly calcifuge flowering plants. The family is large, with roughly 4000 species spread across 126 genera, making it the 14th most speciose family of flowering plants...

, in which they are now treated as a subfamily, the Monotropoidiae. Before this, they were sometimes also placed in the family Pyrolaceae

Pyrolaceae

Pyrolaceae was a small family of flowering plants under the old Cronquist system of plant classification. It included the four genera Chimaphila, Moneses, Orthilia, and Pyrola, and sometimes also the eight genera formerly usually placed in the family Monotropaceae.Recent genetic research by the...

, which is now also in the Ericaceae.

All monotropoids are myco-heterotrophs, meaning that they contain no chlorophyll

Chlorophyll

Chlorophyll is a green pigment found in almost all plants, algae, and cyanobacteria. Its name is derived from the Greek words χλωρος, chloros and φύλλον, phyllon . Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to obtain energy from light...

 and therefore do not get their food from photosynthesis

Photosynthesis

Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

, but instead derive both nutrients and carbon sources from parasitizing on fungi.