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Niebla flabellata
is recognized by having salazinic acid and by the development of flattened
thallus segments. The basal branches are usually tufted, arising from a
holdfast attached to small stones, rock walls of canyons, or along steep
sides of large boulders. The branches are usually irregular in shape,
varying from nearly linear to somewhat elliptical, or almost rotund, all of
which appear with various lacerations, contortions and spine-like branchlets.
The lack of any
regularity to the thallus shape, other than its rounded tufted outline of the
main branches, makes it difficult to distinguish from other related species such
as N. josecuervoi and N. effusa. However, it is helpful to
understand that species like N. josecuervoi are distinguished by the more
uniform linear-like shape of the branches. This feature appears correlated
with the development of prismatic to sub-teretiform branches that are seen in most
species of the genus. Those with a flattened branch morphology (still
somewhat prismatic in outline) such as N. caespitosa, N. dilatata, and
N. flabellata, exhibit a wide range of variation in the shape of the thallus
and its branches, probably because of a flattened morphology that allows for
more environmental variation in the development of various shapes.
Niebla effusa,
a closely related species to N. flabellata, shows partial flattened
segments, generally where the branches appear to divide, especially near apex.
This species usually spreads over the ground (terricolous), often initiating
between small rocks, rather than growing on the rocks (saxicolous).
Niebla flabellata is
frequently encountered in the Southern Vizcaíno
Desert of Baja California, from Cañón San Fernando to the Vizcaíno
Peninsula,
and is also found locally on the southern part of Isla Cedros. More than
100 specimens were determined by TLC. The most abundant occurrences are on
lava along the beach areas between Guerrero Negro and Punta Santa Rosalillita,
and it is also common on smooth pebble-stones along beaches.
In 1979, Spjut and Edson collected a 1 kg sample from Playa Altimar for cancer
research; the voucher specimen was initially identified by Mason Hale as
Desmazieria josecuervoi.
Niebla flabellata,
however, is usually found with other species, especially Vermilacinia
paleoderma. In 1985, a sample collected
for anticancer research near Rancho San Andrés was difficult to separate from
N. caespitosa and N. flagelliforma, both of which are now
distinguished by the presence of divaricatic acid. These species were not
known then. They were first recognized in 1986 when a serious study of
Niebla was undertaken by Spjut, employing TLC. However, Bowler and
Marsh in the Greater flora of the Sonoran Desert (2004) find it difficult to
distinguish such species, and for those who find the genus difficult to work
with, they may wish to refer these species to N. josecuervoi and N.
homalea, respectively. Another species, N. spatulata, which has
hypoprotocetaric acid, also occurs with N. flabellata at all known
locations where N. spatulata has been found; these can only be
distinguished by their lichen substances.
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