Type. Ad flum.
Guainia v. Rio Negro supra ostium fluminensis
Casiquiare (Amazonas, Venezuela), 1854,
R. Spruce 3551 (holotype K, isotype N Y ).
Lisianthus (sect. Adenolisianthus) arboreus Spmce ex
Progel, n. bras. 6(1): 240. 1865.
Adenolisianthus arboreus (Spmce ex Progel) Gilg, Nat.
Pflanzenfam. 4(2): 98. 1895.
Irlbachia alata (Aublet) Maas subsp. arborea (Spmce
ex Progel) Persoon & Maas, Proc. Kon. Ned. Akad.
Wetensch. Ser. C. 88(4): 410. 1985
Progel (1865) established the section Adenolisianthus
in Lisianthus with two species, L. arboreus
Spmce ex Progel and L. virgatus Progel,
on the basis ofa glandular gynobase. Gilg (1895)
elevated the sectional name to generic status,
providing distinction from Chelonanthus by minute
pollen exine diflferences. The specimens before
us exhibit neither of these diflferences. They
do exhibit a shrubby tendency-a quality which
perhaps led to Spruce's epithet arboreus. This
epithet, however, cannot be retained when transferred
to Chelonanthus because it would thus be
a homonym (C arboreus Britton, =Rogersonanthus
arboreus (Britton) Maguire & Boom).
Therefore, a new name is here selected.
The pollen of Chelonanthus fruticosus, however,
also is distinctive in not exhibiting the
abundant globular processes so conspicous in the
other species of the genus admitted here.
The shmbby habit and pollen distinction may
well argue that this species is misplaced in Chelonanthus.
The inflorescence, contrarily, argues
that the species is properly placed.
Specimens examined. COLOMBIA, vaupes: 4-5 ft,
flowers green-yellow, Mt. Chiribiquete, quartzite base,
summit about 800-1200 ft, above forest floor, 1700-
2100 ft above sea level, Macaye River, 24 Jul 1943,
Schultes 5614 (GH, NY); same locality, Schultes 5441
Besides the isotype, Spruce 3551, there are five
additional collections of this well-marked species
at N Y , cited above, all of the Yavita-Pimichin
area on the divide between the Atabapo and
Guainia drainages. The species is evidently thus
restricted geographically, and is clearly marked.
It a satisfaction to have these new collections of
this taxon, which previously had been known
only from the type.