Monographs Details: Randia ruiziana DC.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Scientific Name:Randia ruiziana DC.
Description:Distribution and Ecology - Distribution. Peru, Bolivia, northern Brazil, Suriname, and French Guiana. PERU. Huánuco: montibus ad Pozuzo, Ruiz 31 (photo of type from B). Loreto: Middle Ucayali, Tessmann 3255; Pongo de Manseriche, Río Marañon Valley, alt 150 m, Killip, Smith & Dennis 29128; prope Tarapoto, 1855-6, Spruce 4906; prov. Alto Amazonas, along Río Marañon near Teniente Pinglo, just above Pongo de Manseriche, alt 250-300, Wurdack 2082. Amazonas: mouth of Río Santiago, Tessmann 4168. Madre de Dios: Iberia, Miraflores, Río Tahuamanu, Seibert 2132. Puerto Melendez, Tessmann 3912. BOLIVIA. Amazon Basin, Rurrenabaque, Cardenas 1261. BRAZIL. Para: Upper Cupary River, Krukoff 1095, 1172. Amazonas: near mouth of Rio Embira, lat 7° 30' S, long 70° 15' W, Krukoff 4918; Upper Río Negro Basin, São Felipe, 7 Apr 1948, Schultes & Lopez 9782 (cultivated). Terr. Acre: basin of Río Purus, near mouth of Rio Macauhan, lat 9° 20' S, long 69° W, Krukoff 5375; Errere, 1870, Prentiss sn. Mato Grosso: 1891-92, Spencer Moore 441, 630. SURINAME. Campo Dungeoman, Saramacca River, 3 Jul 1944, Maguire 24043. FRENCH GUIANA. Riviere Mana, Sant Sabbat, Halle 543.

Discussion:

Gardenia longiflora Ruiz & Pavon, FI. Per. 2: 67. pl. 219, fig. a. 1799, not Randia longiflora Lam., 1789 nor R. longiflora Salisb., 1805.

Type. Posuso, Department Huanuco, Peru, Ruiz & Pavon.

Bremekamp characterized R. ruiziana as having the “calyx inside glabrous” as opposed to R. formosa, in which the “calyx inside at the base sericeous” [Fl. Suriname, 4(1): 166. 1934], A similar statement is made in Medel. Bot. Mus. Utrecht 11: 265. 1934 as follows: “The flowers of R. ruiziana are more than twice as long as those of R. formosa, the calyx is entirely glabrous inside and not, as in that species [R. formosa], sericeous at the base.” An examination of extensive material of R. ruiziana and R. formosa shows that hairs are present in R. ruiziana at the base of the calyx tube within, but they are few or sparse and do not present a conspicuous appearance, whereas in R. formosa and varieties the hairs at the base of the calyx tube within are dense, presenting an abundance of sericeous, white, erect pubescence.

Some collections examined are intermediate between R. ruiziana and R. formosa. Klug 2272 and 2248 from Dept. Loreto, Peru, has a corolla tube elongated to 15 cm, resembling R. ruiziana in this respect, but the calyx tube and hypanthium are only 10 mm long, and the calyx lobes 8-9 mm, thus coming within the measurements for R. formosa. Similarly, in Prentiss from Errere, Brazil, the corolla lobes, only 3.7 cm long, approach the measurements of R. formosa. Moore 441, 630 from Matogrosso, Brazil, has corolla tubes and lobes intermediate in size. Haught 6247 from San Antonia, Dept. Cundinamarca, Colombia, shows measurements for the corolla of 14 cm long for the tube (placing it in R. ruiziana), 4-4.5 cm for the lobes (similar to measurements for R. formosa), calyx tube 9-11 mm long (as in R. ruiziana), hypanthium and calyx tube 13-15 mm long (as in R. ruiziana), but with the interior of the base of the calyx tube densely sericeous, as in R. formosa. Lanjouw 520 from Suriname has a corolla tube 14.5 cm long, but the corolla lobes are only 3 cm long, as in R. formosa, and the calyx tube and hypanthium and calyx lobes have lengths relegating them to R. formosa. In general, the two taxa can be distinguished, and at present are being retained as distinct, but closely related, species.

Distribution:Peru South America| Bolivia South America| Brazil South America| Suriname South America| French Guiana South America|