Blitum is a genus of flowering plants in the amaranth family Amaranthaceae (subfamily Chenopodioideae), placed in the order Caryophyllales. The genus comprises around 12 species of non-aromatic annual or perennial herbs that were long treated as part of the larger genus Chenopodium, as well as species previously placed in Monolepis and Scleroblitum. Phylogenetic research published by Fuentes-Bazan and colleagues in 2012 showed that these species are more closely related to Spinacia (spinach) than to the core Chenopodium group, leading to their reinstatement as a separate genus. Together with Spinacia, Blitum is placed in tribe Anserineae (also known as Spinacieae).
The plants are glabrous or occasionally covered with stipitate vesicular hairs, and young growth can be sticky. Stems are erect, ascending, or prostrate, arising from the base and either unbranched or sparsely branched. The alternate leaves consist of a petiole and a simple blade that may be triangular, triangular-hastate, triangular-lanceolate, or spathulate, with entire to dentate margins; basal leaves are often long-petiolate and may form a rosette. Flowers are borne in compact glomerules arranged in a spike-like fashion, and are bisexual or pistillate. Each flower bears three to five herbaceous, unkeeled perianth segments, one to five stamens, and an ovary with two to four stigmas. A distinctive character of the genus is that the perianth becomes fleshy and succulent in fruit in several species, giving the fruiting spikes a berry-like, often red appearance — as seen most vividly in Blitum capitatum (strawberry blite), the type species.
Species are distributed across Asia, Europe, North Africa, the Americas, and Australia. Notable members include Blitum bonus-henricus (Good king henry), a traditional European edible herb long cultivated as a leaf vegetable; Blitum capitatum (strawberry blite), grown ornamentally for its bright red fruiting heads; and Blitum virgatum (leafy goosefoot), native to Europe and Asia. The genus was first formally described by Carl Linnaeus in Species Plantarum (1753), and the type species, Blitum capitatum, was described at the same time.
Etymology
The name Blitum is the Latinised classical form used by Carl Linnaeus when he formally described the genus in Species Plantarum in 1753. The term traces to classical Latin and Greek usage for a type of leafy herb. The genus name had been superseded for over a century while its species were subsumed into Chenopodium, but was formally reinstated in 2012.
Distribution
Species of Blitum are found across Europe, Asia, North Africa, the Americas, and Australia. European species include Blitum bonus-henricus and Blitum virgatum; North American representatives include Blitum capitatum (strawberry blite, also naturalized in Europe), Blitum nuttallianum, and Blitum californicum. Blitum atriplicinum is native to Australia, Blitum antarcticum to southern Chile and Argentina, and Blitum venetum is known from northeastern Italy.
Taxonomy Notes
Blitum was first described by Linnaeus in 1753 with Blitum capitatum as the type species. From the mid-19th century onward, its species were folded into genus Chenopodium (as subgenus Blitum) and into related genera Monolepis and Scleroblitum. Phylogenetic work by Fuentes-Bazan et al. (2012) demonstrated that these species form a clade more closely allied to Spinacia than to Chenopodium proper, and the genus was resurrected. Blitum and Spinacia are placed together in tribe Anserineae (syn. Spinacieae) within subfamily Chenopodioideae of Amaranthaceae. GBIF records the family as Chenopodiaceae, which reflects an older circumscription now subsumed into Amaranthaceae under APG treatments.
Cultural Uses
Blitum bonus-henricus (Good king henry) has a long history of use in Europe as a leafy vegetable — the young leaves and shoots were cooked like spinach or asparagus. Blitum capitatum (strawberry blite) produces vivid red fruiting heads that render it attractive as an ornamental, and its young leaves are edible. The genus's close relationship to spinach (Spinacia) reflects a shared history of use as leafy greens in the amaranth family.
