Monographs Details: Chiococca nitida var. amazonica f. cordata (Cowan) Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Description:Distribution and Ecology - Distribution. British Guiana. BRITISH GUIANA. Wabuwak, Kanuku Mts.. alt 600 m, Nov 1948, Wilson-Browne 469B.

Discussion:

Chiococca cordata Cowan, Brittonia 7: 411. 1952.

Type. Mountain top in rain forest, Soirntau, Kanuku Mts., British Guiana, alt 725 m, Sep 1948, Wilson-Browne 230 (Forest Dept. 5707).

This taxon would at first appear to merit specific recognition, because of its cordate or subcordate, subsessile leaves. However, it merges with C. nitida var amazonica as an extreme form of that variety, with which it agrees in having similar corollas of small size (6.5-7.5 mm long). As noted by Cowan (Brittonia 7: 412. 1952), one of the specimens (Wilson-Browne 469A), placed in C. nitida var amazonica, was mixed with paratype material of C. cordata (Wilson-Browne 469B) and growing with it, the two sheets separated only by the character of more lanceolate leaves with leaf apex distinctly acuminate. But, although Cowan states that the petioles in C. cordata are only 1 mm long, my examination of the type collections and of paratype material shows petioles reaching 3 mm in length. Furthermore, some specimens of C. nitida var amazonica in adjacent Venezuela (Steyermark 88457) have leaves with petioles as little as 3-4 mm in length, and with the leaf bases broadly rounded to subtruncate, approaching the same type of leaf shape and size as that of C. cordata.

Distribution:Guyana South America|