PlantaeDB Logo
Login Sign-up

Genus Rottboellia in Family Poaceae

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!

Rottboellia (Rottboellia L.f., family Poaceae, subfamily Panicoideae) is a small genus of tropical grasses comprising approximately 3 species (R. cochinchinensis, R. corymbosa, R. elegans), historically treated within Themeda by some authors (Themeda Rottboellia group; Hsuan & Levine 2008). Native across tropical Africa, Asia, and Australasia, the genus typically inhabits grasslands, savannas, and open woodlands (POWO, 2024; WFO, 2024).

Morphologically, Rottboellia is distinguished by its tall, annual habit and characteristic inflorescence: a raceme of paired, similar, awnless or shortly awned spikelets borne on a cylindrical, often fragile rachis that disarticulates at maturity. The spikelets are sessile or shortly pedicellate, with 2–3 florets; the lower glume is flattened or concave, often rugose or tuberculate (Hsuan & Levine 2008). Leaves are linear with typically pubescent sheaths and ligules. The genus shares the panicoid sister group traits of C3 photosynthesis (native Poaceae). Ovary placentation is superior.

Diversity centers appear in tropical Asia (particularly South and Southeast Asia) and Africa, with R. cochinchinensis (syn. R. exaltata) being the most widespread and ecologically significant. Typical habitats include disturbed ground, roadsides, and seasonally dry grasslands from lowland to mid-elevations (GBIF, 2024). Dispersal is primarily abiotic via the free-threshing grain-like caryopsis.

Taxonomically, Rottboellia is phylogenetically nested within Themeda, necessitating its recognition either as a distinct clade within Themeda or its synonymy under Themeda sensu lato (Themeda Rottboellia group; Hsuan & Levine 2008; Butcher et al., 2012). While monographic work remains ongoing, consensus recognizes Rottboellia as a morphological entity (APG IV, 2016). Synonymization with Themeda is gaining support but remains debated.

Human relevance is significant: R. cochinchinensis is a globally problematic invasive weed in crops and natural areas, while R. corymbosa is occasionally used as forage or for thatching. Conservation status is generally not evaluated but is likely stable; however, the limited taxonomic resolution and declining habitat pose research needs.

Sources: APG IV, 2016; Butcher et al., 2012; Hsuan & Levine, 2008; POWO, 2024; WFO, 2024; GBIF, 2024.

Pick a Species to see its components: