Senna dariensis var. gatunensis (Britton) H.S.Irwin & Barneby

  • Authors

    Howard S. Irwin, Rupert C. Barneby

  • Authority

    Irwin, Howard S. & Barneby, Rupert C. 1982. The American Cassiinae. A synoptical revision of Leguminosae tribe Cassieae subtrib Cassiinae in the New World. Mem. New York Bot. Gard. 35, part 1: 1-454.

  • Family

    Caesalpiniaceae

  • Scientific Name

    Senna dariensis var. gatunensis (Britton) H.S.Irwin & Barneby

  • Type

    Holotypus, NY (2 sheets)!—Cassia fruticosa var. gatunensis (Britton & Rose) Schery, Ann. Missouri Bot. Gard. 38(1) [=F1. Panama 5(31)]: 81. 1951.

  • Synonyms

    Chamaefistula gatunensis Britton, Cassia fruticosa var. gatunensis (Britton) Schery

  • Description

    Variety Description - Lf-rachis as long or commonly somewhat longer than petiole; venation of upper lft-face either immersed or prominulous but not or scarcely depressed, the lower face paler than the upper but not notably glaucescent; sepals of var. dariensis except more promptly deciduous; long petals 15-25 mm.—Collections: 29. [Key: "Pod 4.5-6.5 mm diam; anthers glabrous or minutely strigulose in the grooves; Costa Rica, Panama and n.-w. Colombia. Sepals densely gray-puberulent overall, the longest 6-9.5 mm; lfts densely pubescent dorsally; n.-e. Costa Rica; lowland Panama, from Canal Zone e. into n.-w. Colombia. Lower face of lfts strigulose with forwardly appressed hairs 0.1-0.25 mm; petiole 1.5-4 cm; sepals promptly deciduous."]

    Distribution and Ecology - Habitat of var. dariensis and sympatric with it in Canal Zone and (locally) Darien, but apparently commonest on the Caribbean slope of the Divide in San Bias, Panama, extending e. and s.-e. to Turbaco in Bolivar, Colombia and centr. Choco; one disjunct record from n.-e. Costa Rica (Heredia).—Fl. IV-XII, perhaps throughout the year.

  • Discussion

    Very close to typical var. dariensis, indeed identical in the narrow pod, but differing not only in vesture, as overemphasized by Schery (1951), but also in the generally longer petioles, less impressed venation of the leaflets’ upper face, and deciduous sepals. Where var. dariensis and var. gatunensis cohabit, as near Gamboa on the Canal and on the Pacific slope in Darien, they are readily distinguished by these features and we have seen no doubtfully intermediate specimens. Our one record from Choco (White & Warner 99, MO) is unusual in the pallor of the dorsal leaf-venation and exceptionally short-beaked anthers; we lack the pod, necessary to confirm the identity. The var. gatunensis was encountered first by Humboldt and Bonpland, in ripe fruit in April, 1801, near Turbaco, Colombia, but the specimens (Bonpland 1425, P) were either not seen or ignored by Kunth when he was working up the Caesalpinioideae for Nova Genera & Species.

  • Distribution

    Canal Zone Panamá Central America| Darién Panamá Central America| Bolívar Colombia South America| Chocó Colombia South America| Heredia Costa Rica Central America|