PlantaeDB Logo
Login Sign-up

Genus Biarum in Family Araceae

In botanical taxonomy, a genus (plural genera) is a rank used to group closely related species within a family. In the hierarchy, genus sits below family and above species.

Genera are defined by shared morphological, anatomical, and genetic characteristics (for example, features of flowers, fruits, seeds, or leaves) that indicate a close evolutionary relationship among the species they contain.

Each genus can include one or more species. Examples include Rosa (roses) and Solanum (nightshades, including tomato and eggplant).

Do you wish to read more about plant taxonomy? Click here!

Genus Description

Suggest a correction!

Biarum (Schott) belongs to the Araceae and comprises tuberous, mostly winter-growing geophytes totaling approximately 20 species (Mayo et al., 1997; Bown, 2000; Kew, 2024). Its distribution spans the Mediterranean basin from Morocco and Spain east to Turkey, Cyprus, the Levant, and northern Iran, with a main center of diversity in Turkey (Mayo et al., 1997; Kew, 2024). The type species is Biarum davallii (Schott) (Bown, 2000).

Diagnostic morphology sets Biarum apart from nearby genera by a combination of a usually erect, tubular to campanulate spathe that typically persists after anthesis, a short- to long-exserted spadix, and a dense, often dark, central appendix; inflorescences arise at or just above soil level (Mayo et al., 1997). Plants are monoecious with unisexual flowers: male flowers are 2–4-staminate, sometimes with occasional staminodes, and female flowers contain 1–2 orthotropic ovules per locule and usually have short or inconspicuous styles (Mayo et al., 1997). Vegetatively, the group bears one to several leaves that are often produced at or after anthesis and may have parallel or subparallel venation; underground organs are tuberous rhizomes (Mayo et al., 1997; Bown, 2000). Fruits are globose to subglobose berries with brown seeds (Mayo et al., 1997). The genus thus differs from Eminium, often by spathe persistence and spadix architecture (Schott, 1860; Kew, 2024), and from Helicophyllum by the absence of tightly coiled inflorescences (Boyce, 2008).

Diversity and range: Biarum is primarily Mediterranean in distribution, with several species in the eastern Mediterranean (Greece, Turkey, Cyprus) and the Levant, and outliers reaching Iran; North African taxa include B. tenue and B.bovei (Bown, 2000; Kew, 2024). Species occur in scrub, phrygana, rocky slopes, light woodland, and open ground, commonly on limestone, from sea level to mid-elevations (Mayo et al., 1997). There is pronounced local endemism in Anatolia and the Levant (Kew, 2024). Chromosome base numbers are established as x=7, with n=7 recorded in B. davallii (subsp. atticum) and other Mediterranean taxa (Conti et al., 2000).

Intrinsic biology: Biarum blooms from autumn to early spring, when flies and beetles attracted by a fetid scent likely act as pollinators (Mayo et al., 1997). Fruits mature in early to mid-summer, with fleshy berries suggesting dispersal by birds or small mammals; seedling recruitment follows the Mediterranean-type rainfall regime (Mayo et al., 1997).

Taxonomy and phylogeny: The genus has long been recognized, and its circumscription is broadly stable in modern accounts (Schott, 1860; Mayo et al., 1997). However, species delimitation varies between treatments and regional floras, and different authors have transferred certain taxa to Eminium or Helicophyllum, leading to differences in species counts (World Flora Online, 2024; Kew, 2024). Molecular phylogenetic studies support Biarum within the Aroideae and often retrieve Eminium as nested within Biarum or as its sister group, suggesting that future re-circumscription may be required (Ruberti et al., 2019).

Human relevance: Several species are cultivated in rock gardens or alpine houses and valued for their early bloom and distinctive inflorescences (Boyce, 2008). As wild plants, they are localized and rarely weedy; no significant invasive behavior is recorded (Kew, 2024).

Conservation and outlook: Some species are locally scarce due to habitat loss and over-collection, and taxonomic instability complicates conservation assessments; improved species-level phylogeny and standardized census are priorities (Boyce, 2008).

Pick a Species to see its components: