Greenhouse 2
1. Acacia cornigera - bull-horn acacia (Mimosaceae)
A famous mutualism: the acacia provides food and shelter for ants, which in turn protect the plant from herbivores. The shelter is in the form of hollow stipular thorns. The food comes as "Beltian bodies", little globs of oil and protein at the tips of leaflets (look closely). These are named for the "Naturalist of Nicaragua", Thomas Belt. Acacia is a dominant legume genus of tropical deciduous forests and savannas.
2. Ficus nekbudu - Kaffir fig (Moraceae)
A strangling fig native to tropical Africa. Like many species in this large genus (ca. 800 species) found in all three tropical floristic regions, the plant can start as an epiphyte and slowly envelope its support. The figs are pollinated by wasps and, as in the orchids, a particular species of wasp often has coevolved to pollinate a particular species of fig. Click here to see images of a strangler fig which has killed its host tree and now has a hollow center.
3. Monstera deliciosa - swiss cheese plant, monstera (Araceae)
This genus (from the Neotropics) and relatives are some of the dominant epiphytes or hemi-epiphytes in tropical forests. This species starts rooted in the ground and grows towards the dark (i.e., tree trunks); once attached it grows up to the light - hence it is a "roving" hemi epiphyte. The adaptive value of the fenestrations ("windows") is still debatable. Click to see a Monstera plant eating a car!
4. Osmanthus heterophyllus — holly olive (Oleaceae)
This genus in the olive family is mostly native to warm, wet temperate forests (subtropical humid) but with one species (O. americanus) in southeastern North America (southeastern United States, Texas to Virginia). This biome type is often characterized by tough, evergreen leaves adapted to year-round growing conditions but with marked seasonality in temperature. Similar leaves with sharp serrations (“holly”-leaves) can be found in the Mediterranean biome as adaptations to marked seasonality in moisture availability.
5. Aristolochia grandiflora — pelican flower (Aristolochiaceae)
This genus of dutchman’s-pipe includes some of the more dramatic viney plants of tropical forests. The species is a deciduous vine with enormous flowers (the largest flower in the New World) that emit an odor that humans consider unpleasant but attractive to carrion-loving insect pollinators. The plant is native to the Caribbean, and has been introduced to Florida in the United States as an attractor of butterflies.
Greenhouse 3A
6. Kohleria sp. — (Gesneriaceae)
This herb is a member of the “African violet family,” which is mostly found in the tropics. The family is characteristic of tropical rain forest understories, and its members often have fuzzy leaves that are oppositely arranged on the stem. (Note the many different plants in this family, arranged from here to the greenhouse door!) Flowers of the Neotropical species are usually funnel-shaped for pollination by hummingbirds — an almost strictly Neotropical group of birds.
7. Epidendrum sp. - orchid (Orchidaceae)
As you might guess based on its latin name, this group of orchids is characteristically epiphytic in the Neotropical wet and cloud forests. Their stems form pseudobulbs for water storage. Like all orchids, the flowers are intricately arranged and have specialized forms of animal (often bee) pollination. The seeds are numerous and light, ideal for dispersal to branches and stems of host trees.
8. Welwitschia mirabilis (W. bainesii) - (Welwitschiaceae)
This ancient gymnosperm endemic is found only in the Namib desert of southwestern Africa. Note the peculiar morphology - a caudex producing two leaves with basal meristems. These leaves later fray so as to appear more numerous. It has a taproot to 3 m deep but this just serves to anchor the plant and doesn't absorb or transport water. Since it virtually never rains where this plant grows, it has adapted as a nephelophyte by getting its water via fog absorbed by stomates on the upper leaf surface. [Also in the succulent house. For more information see the display case on the 1st floor hallway near room 122.]
9. Myrmecodia sp. — antplant (Rubiaceae)
A genus of epiphytic myrmecophytes (ant plants) native to the Southeast Asian rainforests. They form a symbiotic relationship with ants. Ant plants provide habitats for ant colonies high up into the forest canopy, protecting them from the elements and also predators because of the spines. Ants likewise provide defense for the plant, prevent tissue damage, and also provide nutrients to the plants by leaving wastes within the tunnels inside the caudex. Special glands lining the tunnels then absorb nutrients for the plant. Link to these images of the inside cavity of the ant-stem goes to the website of Christian Puff, University of Vienna, Austria, who is a specialist on the coffee family.
Greenhouse 4
10. Rhizophora mangle - red mangrove (Rhizophoraceae)
The dominant mangrove in the Neotropics, especially prevalent close to the sea. Several adaptations to the halophytic life style (what does that mean?) are evident: tough, evergreen leaves; prop roots. Pneumatophores are not evident on this young plant - why not perhaps?
11. Platycerium bifurcatum – Staghorn fern (Polypodiaceae)
This epiphytic fern grows in the Old World tropics. As the leaves of the plant die, they remain attached to the base of the plant. As the dead leaves accumulate, they form humus as the base of the plant, catching and storing water and nutrients – a “trash basket” into which roots can penetrate. These large “sponges” at the base of the plant are capable of holding gallons of water.
12. Blechnum gibbum — dwarf tree fern (Blechnaceae or Cyatheaceae)
This tree fern genus is cosmopolitan in tropical regions of the southern hemisphere and is a close relative of the widespread genus Cyathea. Tree ferns are very characteristic of moist tropical mountains or cloud forests, with a few reaching into temperate rainforests only in the southern hemisphere.
Greenhouse 7 (Desert House)
13. Pachypodium laneri — bottle tree (Apocynaceae)
This bizarre treelet from Africa (other species in Madagascar) are found in dry thorn forests. The stem enlarges and becomes a water holding “bottle”. All members of the family, including the milkweeds (often placed in Asclepiadaceae), have a well-developed latex system — like so many other succulents – for protecting its costly parts from herbivores.
14. Euphorbia trigona — African milk plant (Euphorbiaceae)
This genus contains ca. 2000 species and is cosmopolitan. This species is a stem succulent from western Africa, and grows up to six feet tall as a spiny shrub-like tree. This genus has evolved species like this one that closely mimic cacti, which are confined to the New World (except for a handful of epiphytes). Although sometimes spurges are extremely similar to cacti, it is very easy to differentiate the two, even when not in flower. Prick a spurge stem and then a cactus stem. What's the difference?
15. Cereus hexagonus — a cererioid cactus (Cactaceae)
This cactus is a stem succulent from the West Indies and northern South America. The family is confined to the New World, except for a few epiphytic species of Rhipsalis. It contains ca. 2,000 species and includes the stem succulents that are most characteristic of New World deserts. Compare this species to members of the Euphorbiaceae nearby.
16. Didierea trollii — octopus tree (Didiereaceae)
A representative of a tiny family that is endemic to southwestern Madagascar. The family contains only 11 species in 4 genera. It looks much like the American Cactaceae, although many thought this was simply convergence. Its mysterious relationships were illuminated with DNA sequences that showed that it was in fact somewhat related to cacti – perhaps indicating parallel rather convergent evolution in growth form in two distinct areas of the world.
17. Ceropegia radicans — rosary vine (Apocynaceae)
This diverse genus of about 200 viney species belongs to the milkweed group of the dogbane family (Apocynaceae). This species is from arid regions of south Africa. The green flowers have tubes are lined with small hairs that point downward to form a trap for small flies. When flies are attracted into the flower by the odor they are prevented from escaping until the hairs wither, the pollinia of the Ceropegia flower being attached to the flies’ bodies when they escape.
Greenhouse 8 - Tropical High House
18. Calliandra haematocephala — red powderpuff (Fabaceae)
A species-rich genus of the most important family of trees of tropical wet and dry forests – the legume family. Although some are trees, other members of the genus are more herbaceous. Compound leaves are common in the family and in tropical forests, in general. The striking colored large cluster of many, small flowers are adapted to bird pollination in all three tropical regions of the world.
19. Pachira quinata - shaving-brush tree (Malvaceae/Bombacaceae)
This tree is found in the subtropical deciduous forest of Central America. Note the presence of trunk thorns so characteristic of these dry forests. What is their purpose you think? The Malvaceae is a family typically showing compound leaves.
