''Menodora'' is a genus of perennial plants and

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

s in the olive family Oleaceae. Its 23 species (as per Green 2003) are found in the temperate

Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with th ...

and in southern Africa. These are uniform species of deserts and arid grasslands or savannas.

Description

The usually bisexual flowers have a united

calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...

with 5-10 lobes (rarely more), while the

corolla Corolla may refer to: *Corolla (botany), the petals of a flower, considered as a unit *Toyota Corolla, an automobile model name * Corolla (headgear), an ancient headdress in the form of a circlet or crown * ''Corolla'' (gastropod), a genus of moll ...

is similarly united but with 4-6 lobes. The corolla is a pretty, bright yellow (except for ''M. spinescens'', whose corollas are white), and is often scented. The fruit is a didymous, bilobed capsule with each globose

locule A locule (plural locules) or loculus (plural loculi) (meaning "little place" in Latin) is a small cavity or compartment within an organ or part of an organism (animal, plant, or fungus). In angiosperms (flowering plants), the term ''locule'' usu ...

or lobe containing 2-4 seeds. In the majority of species, each locule also features circumscissile dehiscence. Vegetatively, the plants are generally unremarkable, with a "green-stick" look that is common to many desert plants. In the dry seasons, plants may lose their generally small or reduced leaves altogether. Leaf shape within the genus is highly variable, ranging from short and linear to almost feathery and pinnatisect. Leaves are most commonly found arranged in opposite pairs, but in some individuals may be predominantly alternate.

Etymology

Willis Jepson mistakenly suggested that the origin of the genus name was rather obscure, perhaps deriving from the Greek for "half-moon spear" for the appearance of the dehisced fruit on its pedicel. In reality, the name was specifically derived from the Greek μενος (''menos''), meaning "force," and δωρον (''doron''), meaning "gift," referring to the sustenance the plants provided to the horses of

Humboldt Humboldt may refer to: People * Alexander von Humboldt, German natural scientist, brother of Wilhelm von Humboldt * Wilhelm von Humboldt, German linguist, philosopher, and diplomat, brother of Alexander von Humboldt Fictional characters * ...

and Bonpland (1809) when they first encountered the genus in the present state of Hidalgo in Mexico.

Selected species

Taxonomy

Menodora longiflora ''Menodora'' is a genus of perennial plants and shrubs in the olive family Oleaceae. Its 23 species (as per Green 2003) are found in the temperate Americas and in southern Africa. These are uniform species of deserts and arid grasslands or savann ...

'' has occasionally been treated as the monotypic genus ''Menodoropsis'' (Small, 1903) due to the extraordinary length of its corolla tube (to nearly 6 cm, as opposed to typical lengths of 0.3 to 0.7 cm in most other species), but based on both morphological and molecular data it plainly belongs within ''Menodora''. Small took the name for the genus from one of the sections of the ''Menodora'' recognized by Asa Gray (1852). Neither the sectional classification of Gray (1852) nor Steyermark (1932) have been upheld by recent molecular studies. One of the more distinctive things about this genus is the pattern of disjunction or non-continuous distribution. In the

, the distribution jumps over the tropics, with only a few species whose individual distributions just cross into the tropics (e.g., north to central

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

, and south to Oaxaca in Mexico). This is a common pattern found in many genera, but not many others with a similar amphitropical distribution also have connections across the Atlantic with Africa. This intercontinental distribution of ''Menodora'' was often cited as evidence of continental drift or the breakup of the Pangaea or

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...

n supercontinents, but more recently it has been judged to be the result of long distance dispersal.

References

{{Taxonbar, from=Q2712889 Oleaceae genera Taxa named by Aimé Bonpland Taxa named by Alexander von Humboldt