Question: Which plant can be found on more continents, Tillandsia or Lamarckia?
Context: Lindernia dubia is a species of flowering plant known by the common names yellowseed false pimpernel and moist bank pimpernel.  It is a member of the "new" plant family Linderniaceae, and it is sometimes treated as a member of the families Scrophulariaceae and Plantaginaceae.  It is native to much of the Americas from Canada to Chile, and it can be found on other continents as an introduced species.  It grows in wet habitat, such as riverbanks, pond margins, and meadows.  It is an annual herb growing a mostly erect, branching stem to exceed 30 centimeters in height.  The oppositely arranged leaves vary in size and shape, from lance-shaped to oval, toothed or not, and under one to over three centimeters long.  Flowers emerge from upper leaf axils.  Each has a calyx of five narrow, linear sepals.  The tubular corolla is up to a centimeter long, white in color with a blue or purple tint, and lipped at the mouth, the lower lip with three rounded lobes.  The fruit is a capsule containing yellow seeds. Erodium moschatum is a species of flowering plant in the geranium family known by the common names musk stork's-bill and whitestem filaree.  This is a weedy annual or biennial herb which is native to much of Eurasia and North Africa but can be found on most continents where it is an introduced species.  The young plant starts with a flat rosette of compound leaves, each leaf up to 15 centimeters long with many oval-shaped highly lobed and toothed leaflets along a central vein which is hairy, white, and stemlike.  The plant grows to a maximum of about half a meter in height with plentiful fuzzy green foliage.  The small flowers have five sepals behind five purple or lavender petals, each petal just over a centimeter long.  The filaree fruit has a small, glandular body with a long green style up to 4 centimeters in length. Tillandsia is a genus of around 650 species of evergreen, perennial flowering plants in the family Bromeliaceae, native to the forests, mountains and deserts of Central and South America, the southern United States and the West Indies.  They have naturally been established in diverse environments such as equatorial tropical rain forests, high elevation Andes mountains, rock dwelling (saxicolous) regions, and Louisiana swamps, such as Spanish Moss ("T. usneoides"), a species that grows atop tree limbs.  Airplant is a common name for plants in this genus.  Most "Tillandsia" species are epiphytes – i.e. they normally grow without soil while attached to other plants.  Some are aerophytes or "air plants", which have no roots and grow on shifting desert soil.  Generally, the thinner-leafed varieties grow in rainy areas and the thick-leafed varieties in areas more subject to drought.  Most species absorb moisture and nutrients through the leaves from rain, dew, dust, decaying leaves and insect matter, aided by structures called trichomes. Lamarckia is a Eurasian and African plant in the grass family. Amorpha fruticosa is a species of flowering plant in the legume family (Fabaceae) known by several common names, including desert false indigo, false indigo-bush, and bastard indigobush.  It is found wild in most of the contiguous United States, southeastern Canada, and northern Mexico, but it is probably naturalized in the northeastern and northwestern portion of its current range.  The species is also present as an introduced species in Europe, Asia, and other continents.  It is often cultivated as an ornamental plant, and some wild populations may be descended from garden escapes. A cushion plant is a compact, low growing, mat forming plant that is found in alpine, subalpine, arctic, or subarctic environments around the world.  The term "cushion" is usually applied to woody plants that grow as spreading mats, are limited in height above the ground (a few inches at most), have relatively large and deep tap roots, and have life histories adapted to slow growth in a nutrient poor environment with delayed reproductivity and reproductive cycle adaptations.  The plant form is an example of parallel or convergent evolution with species from many different plant families on different continents converging on the same evolutionary adaptations to endure the harsh environmental conditions. Halimodendron is a monotypic genus of legume containing the single species Halimodendron halodendron, which is known by several common names, including common salt tree and Russian salt tree.  It is closely related to the genus "Caragana".  It is native to Russia and southern Asia, but it can be found on other continents where it is an introduced species, and one that is often a noxious weed.  This is a deciduous spiny shrub sprawling to a few meters in maximum width and up to three meters tall.  Stems branch from the base and bear clusters of about four leaflets on sharp spurs.  The ends of branches narrow to spines.  Flowers also appear at the ends of spurs in clusters of two to four pink pealike blossoms each one to two centimeters wide.  The fruit is a black woody inflated pod about 2 centimeters long containing legume seeds.  The plant has a deep and wide root system, with the lateral roots sending up new shoots.  In this manner the plant forms extensive thickets.  When introduced to an area of suitable climate, such as California where it is a known weed, it can invade cultivated land and spread relatively quickly.  It is tolerant of saline soils. Spanish moss (Tillandsia usneoides) is an epiphytic flowering plant that often grows upon larger trees in tropical and subtropical climates, native to much of Mexico, Bermuda, the Bahamas, Central America, South America, the southern United States, and the West Indies as well as being naturalized in Queensland (Australia) known as "grandpas beard" and in French Polynesia.  In the United States from where it is most known, it is commonly found on the southern live oak ("Quercus virginiana") and bald-cypress ("Taxodium distichum") in the lowlands, swamps, and savannas of the southeastern United States from Texas and Florida north through southern Arkansas. Ludwigia palustris is a species of flowering plant in the evening primrose family known by the common names marsh seedbox, Hampshire-purslane and water purslane.  Its native distribution is unclear, but includes parts of the Americas; it can be found on most continents and spreads easily to become naturalized.  It is also cultivated as an aquarium plant.  This is an aquatic or semiaquatic perennial herb which grows in moist to wet to flooded areas.  It is sometimes a weed.  The stem is up to half a meter long and spreads to form mats on the mud, rooting at nodes in contact with the substrate, or floats ascending in the water.  The leaves are oppositely arranged and green to red or purple in color.  Solitary flowers appear in leaf axils.  They are made up of tiny green sepals and no petals.  They yield small capsular fruits containing many minute seeds. The Holarctic is the name for the biogeographic realm that encompasses the majority of habitats found throughout the northern continents of the world, combining Wallace's Palearctic zoogeographical region, consisting of North Africa and all of Eurasia (with the exception of the southern Arabian Peninsula, Southeast Asia, and the Indian subcontinent), and the Nearctic zoogeographical region, consisting of North America, north of Mexico.  These regions are further subdivided into a variety of ecoregions.  Many ecosystems, and the animal and plant communities that depend on them, are found across multiple continents in large portions of this realm.  The continuity of these ecosystems results from the shared glacial history of the realm.  The floristic Boreal Kingdom corresponds to the Holarctic realm.
Answer: Tillandsia