Tolumnia

Maxillarieae subtribe Oncidiinae

Caespitose or scrambling epiphytes producing fan-shaped growths. Stems short. Leaves rigid, bilaterally compressed. Inflorescences axially, long-pedunculate racemes or panicles. Flowers showy. Dorsal sepal and petals free, the lateral sepals variously fused. Lip three-lobed, the callus complex and conspicuous, rarely simple. Column erect, without foot, with conspicuous wings; pollinia 2, on a common stipe and minute viscidium.

Probably named for Tolumnius, a Rutulian mentioned by Virgil.

A genus of about 25 species native to the West Indies and the United States (Florida). This genus was resurrected by Braem (1986) for the plants known in horticulture as “equitant Oncidiums” because of their characteristic fan-shaped growths. Braem and h

1 1' 2 2'

Ackerman, J. D. and M. Galarza-Peréz 1991. Patterns and maintenance of extraordinary variation in the Caribbean orchid, Tolumnia (Oncidium) variegata. Syst. Bot. 16:182-194; Ackerman, J. D. and J. C. Montero Oliver 1985. Reproductive biology of Oncidium variegatum: moon phases, pollination and fruit set. Amer. Orchid Soc. Bull. 54:326-329; Ackerman, J. D. and S. Ward 1999. Genetic variation in a widespread epiphytic orchid: Where is the evolutionary potential? Syst. Bot. 24(2):282-291; Ackerman, J. D., A. Sabat and J. K. Zimmerman 1996. Seedling establishment in an epiphytic orchid: an experimental study of seed limitation. Oecologia 106:192-198; Braem, G. J. 1980. Hispaniella, eine neue Gattung der Oncidiinae. Die Orchidee 31(4):144; Braem, G. J. 1983. Die “Variegaten” Oncidien: Übersicht der Naturformen. Die Orchidee 34(1-3):12-16, 53-58, 88-91; Braem, G. J. 1984. Olgasis: eine vergessene, aber anzuerkennende Gattung der Oncidiinae. Die Orchidee 35(2):63-64; Braem, G. J. et al. ### 1983. Die “Variegaten” Oncidien: Übersicht der Naturformen (4, Teil) mit Bestimmungsschlüssel der Arten. Die Orchidee 34(5):170-175; Braem, G. J. et al. ### 1984. Braasiella, eine neue Gattung der Oncidiinae. Die Orchidee 35(3):113-115; Braem, G. J. 1986. Tolumnia -- der neue, aber doch alte, name für die “variegaten Oncidien.” Die Orchidee 37:55-59; Braem, G. J. 1990. Studies in the genus Oncidium and related genera, part II. The variegata (the plants hitherto known as Oncidium section Oncidium). Schlechteriana 1/90:29-47; Braem, G. J., E. Luckel and M. Russman 1984. Braasiella, eine neue Gattung der Oncidiinae. Die Orchidee 35:113-115; Braem, G. J. and H. Mohr 1988. Die Chromosomenzahlen der “Variegaten Oncidien” (Gattungen Braasiella, Hispaniella, Olgasis, Tolumnia) mit einer Ubersicht der Chomosomenzahlen der Orchidaceae und spezieller Berucksichtigung der Oncidiinae. Schlechteriana 1(2):23-33; Meléndez, E. J. and J. D. Ackerman 1993. The effects of a rust infection on fitness components in a natural population of Tolumnia variegata (Orchidaceae). Oecologia 94:361-367; Moir, W. W. G. 1959. The variegata subsection of Oncidium. Amer. Orchid Soc. Bull. 28(12):901-902; Moir, W. W. G. 1968-1969. Studies in the equitant Oncidium. Phytologia 17(6):425-428, 429-434, 19(1):52-55; Moir, W. W. G. 1972. Variegata Oncidium. Phytologia 23(5):455-459; Moir, W. W. G. 1973. A new species, Oncidium caribense, and three varieties of Oncidium lucayanum. Florida Orchidist 16(3):113-115; Moir, W. W. G. 1975. Oncidium sasseri, the new variegata species from the Bahamas. Florida Orchidist 18(4):155-157; Moir, W. W. G. and M. A. Moir 1970. Variegata Oncidiums. Honolulu, Hawaii; Moir, W. W. G. and A. D. Hawkes 1967. Studies in the equitant Oncidiums, I. Phytologia 15(1):2-12; Osment, W. 1972. Oncidium moirianum, a new species. Florida Orchidist 15(4):147-148; Phang, V. P. E., U. Charanasri and H. Kamemoto 1979. Genome relationships of intra- and intersectional species hybrids of Oncidium triquetrum. Amer. J. Bot. 66(7):805-809; Sauleda, R. P. and M. E. Ragan 1996. A new species of Tolumnia Raf. from Puerto Rico. Orchid Digest 60(4):184-187; Wilson, K. S. 1979. Oncidium guianense (Aubl.) Garay is the appropriate name for Oncidium desertorum Nash ex Withner. Amer. Orchid Soc. Bull. 48(4):361-365; Withner, C. L. 1966. A new equitant Oncidium from Hispaniola (Oncidium compressicaulis). Amer. Orchid Soc. Bull. 35(9):717-719; Withner, C. L. 1967. Two new equitant Oncidiums from Hispaniola. Amer. Orchid Soc. Bull. 36(3):217-220; Withner, C. L. 1967. Oncidium desertorum, a proper name for Oncidium intermedium. Amer. Orchid Soc. Bull. 36(4):309-312; Withner, C. L. 1967. A new Oncidium from the Isle of Pines (Oncidium lyratum). Amer. Orchid Soc. Bull. 36(5):399-401; Withner, C. L. 1976. Observations on equitant Oncidiums as examples of introgressive hybridisation. First Symposium on the Scientific Aspects of Orchids. Univ. Detroit Press; Withner, C. L. 1980. The equitant or variegatum Oncidiums, their varieties, forms and natural hybrids. Orchid Digest 44(3):85-94; Withner, C. L. and H. P. Jesup 1964. Oncidium gauntlettii, a new species from Jamaica. Amer. Orchid Soc. Bull. 33(6):461-463; Withner, C. L. and J. Stevenson 1968. The Oncidium tetrapetalum-pulchellum syngeamon. Amer. Orchid Soc. Bull. 37(1):21-32.