One useful feature for recognizing Rhytidophyllum is that abundant populations often grow in full sunlight along secondary roads. It is relatively easy to observe Rhytidophyllum on a fast-moving bus where clumps of populations of 30-50 individuals are common. The stems are stout and erect and can be more than two meters tall. The leaves are covered with viscous (sticky) hairs.
![](https://gesneriads.info/wp-content/uploads/2020/12/Rhytidophyllum-grandiflorum-roadside.jpg)
Lithophytic (rock dwelling) Rhytidophyllum species represent a habit that is different from the more common terrestrial shrubs. Rock dwellers are smaller (ca., less than 60 cm tall) than their terrestrial relatives. One of my favorite rock-dwellers and most readily observed species is Rhytidophyllum crenulatum that covers the walls of the Morro Castle near the entrance to Havana bay in Havana, Cuba.
![](https://gesneriads.info/wp-content/uploads/2020/12/Rhytidophyllum-crenulatum-Moro-Castle-Havana.jpg)
The flowers of Rhytidophyllum are mostly campanulate (bell-shaped) with tubes that are greenish-yellow or yellow suffused with purple splotches. Unlike the ephemeral flowers of many Gesneria, the flowers of Rhytidophyllum are usually persistent and easily observed above tufts of terminally clustered leaves. A selection of Rhytidophyllum flowers is featured below.
![](https://gesneriads.info/wp-content/uploads/2020/12/Rhytidophyllum-crenulatum.jpg)
![](https://gesneriads.info/wp-content/uploads/2020/12/Rhytidophyllum-rhodocalyx.jpg)
![](https://gesneriads.info/wp-content/uploads/2020/12/Rhytidophyllum-auriculatum.jpg)