An interesting plant in appearance and also in taxonomy.  The genera underwent a huge taxonomic revision (not this species, this time) in 2011, with nearly 2/3 of the species previously considered Henckelia being reassigned, primarily to Codonoboae.  Other species in this genera have been assigned to or from Oreocharis, Loxocarpus, Chirta, Didymocarpus, Roettlera in the past.  This plant seems, as far as I can tell, blissfully unaware of all the changes to its name and grows and blooms ignorant of all the confusion it’s caused.  This species has three synonyms (listed at the way bottom).

There are a few of these ‘Codonoboae types’ in cultivation in the US, but most seem to be species with finer leaves, similar to many Sonerila.  This particular species is fairly robust (maybe would even do ok as a houseplant?), with thick leaves and a very compact growth habit.  I’ve been growing it for maybe 3 or 4 years, and only last year did I cut it for the first time (it’s slow!), but the freshly started plants have proven to be robust.  They can probably get 10-12″ wide and 8″ tall, when full-grown.  It flowers often and the blooms last months.

Available plants are offered in 4″ pots.  The last photo is representative of the size plants available.

Syn.
Didymocarpus amoenus C.B.Clarke in A.L.P.P.de Candolle & A.C.P.de Candolle, Monogr. Phan. 5: 87 (1883)
Henckelia amoena (C.B.Clarke) B.L.Burtt in M.J.E.Coode & al. (eds.), Checklist Fl. Pl. Gymn. Brunei: 438 (1996)
Roettlera amoena (C.B.Clarke) Kuntze in Revis. Gen. Pl. 2: 476 (1891)