Niebla and Vermilacinia (Ramalinaceae) from California and Baja California.  
Spjut, R.W., 1996. ISSN 0833-1475, 208 pp.  
Sida, Botanical Miscellany: 14. Botanical Research Institute of Texas, Inc.

Vizcaíno Peninsula, road
 to Punta Eugenia, 
Spjut & Marin 10560
Apr 1989

Bahía de Santa María
Spjut & Marin 11377
Apr 1990

 W of Rancho San Andrés
~100 km N of Guerrero Negro, Spjut & Marin 9073
May 1985

W of Rancho San Andrés
~100 km N of Guerrero Negro, Spjut 9887A
May 1986

N. caespitosa x N. podetiaforma?
~100 km N of Guerrero Negro
 between Punta Prieta
and Punta Rocosa,on ridge, Spjut 9971, May 1986

Punta Canoas, lower steps
of mesa near the ocean, on
red pumice, Spjut 11230,
Apr 1990

N. caespitosa x N. undulata? Punta Canoas, lower steps
of mesa near the ocean, on
red pumice, Spjut 11231,
Apr 1990

Ridge N of Punta Rocosa, BCN
Spjut 10300, Mar 1988

Mesa W of Pico Santa Monica, Rancho San Francisco
de la Sierra, 325 m elev.
 Spjut & Marin 10921 Apr 1989

Santa Cruz Island
Bratt 2303

San Clemente Island
Santesson 18043, isotype (COLO)

Geographical Distribution

     Niebla caespitosa is identified by its small tuft of flattened, irregularly widened branches with a rough-scabrid cortex and divaricatic acid.  This lichen seems most common along the coastal mountains between Punta Rocosa and Punta Rosarito, and on the edge of a mesa above the escarpment bordering the Vizcaíno Peninsula where it was the only species of Niebla (collected) in association with Vermilacinia cedrosensis.  Near Rancho San Andrés it was found with N. flabellata (salazinic acid) and N. flagelliforma (divaricatic acid).

     Niebla flagelliforma can be difficult to separate from N. caespitosa.  The cortex on the flagelliform branchlets of N. flagelliforma is generally thinner than the primary branch below, and this difference is undoubtedly related to the circinate (coiled or flagelliform) appearance that develops in the upper branchlets.  The branchlets may arise from a dilated segment of the primary basal branch that is narrowed towards base as sometimes seen in N. caespitosa, but in N. caespitosa the cortex remains uniformly thick from base to apex in which the branchlets, therefore, are less likely to become coiled (or flagelliform).

     Niebla dilatata (divaricatic acid), which is similar in its flattened branch morphology, differs by the more rounded lobes that usually appear thicker at margins; its thallus is also usually larger.  Other similar species include N. flabellata (salazinic acid) and N. spatulata (hypoprotocetraric acid), which are easily distinguished by their secondary metabolites.

     Occasional specimens of Niebla testudinaria from California appear similar (e.g., Bratt 3212 from San Luis Obispo Co.).  They are classified by the relatively thicker cortex (< 75µm thick).  It is also important to keep in mind that, unlike N. flagelliforma, N. caespitosa is recognized to occur in the Channel Islands (Santesson type, Bratt 2303), and also mainland California in Ventura Co. (Weber, COLO: S1726).  The collection from Ventura County is similar to specimens of N. testudinaria from Point. Lobos Reserve in Monterrey County.  Differences in the thickness of the cortex, which separates these species, are evident by the contortion of branches and surface features, the branches  of N. caespitosa appear irregularly twisted with a wrinkled surface, in contrast to those of N. testudinaria that appear more rigid and smooth.