Another Letharia!
interesting note-- i found this in the San Bernardino NF collection notes from Kerry Knudson...
NOTES. – Letharia lupina is common throughout San Bernardino National Forest. The species is distinguished in our region by its occurrence in montane habitats at middle to higher elevations and by abundant isidia and soredia. It lacks apothecia in almost all specimens examined from San Bernardino National Forest. Letharia vulpina (L.) Hue is rare and reduced in form in southern California at elevations below 700 meters. It cannot be distinguished morphologically from L. lupina. For more information see Altermann et al. (2016).
Further study...
L. lupina and L. vulpina are very similar, and where they co-occur, they are impossible to reliably separate without genetic testing. Where their range does not overlap, the following morphological differences are recognized:
L. lupina
lemon yellow
long and sparsely-branched
parse isidia
L. vulpina
greenish yellow
abundantly branched
copious isidia
-L. lupina furthermore can be characteristically two-toned, due to the presence of bright yellow cortical patches contrasting with more greenish isidia and greenish tissues surrounding the isidia, although this is apparently not always expressed in every individual thallus.
-L. lupina tends to be higher elevation (190 m and up, warranting the common name “mountain wolf”), while L. vulpina is found in lower elevations (< 1600 m even in southern regions) with warm summers and high occurrence of fog and/or nighttime dew.
-L. lupina is far more common and more broadly distributed than L. vulpina in North America, the latter being restricted to regions west of the Rockies, and virtually absent from the Sierra Nevada.
i think that there are probibly many of the identified L. vulpina here on this project that may actually be L alpina! It appears that L. alpina is actually more ciommon here than L. vulpina.
i would say its a safe bet that if you find letharia w/o apathecia below 623 ft, its definately going to be L. vulpina, whereas if you find Letharia above 5249 feet, its definately going to be L alpina. the elevations in between are going to be more likely L alpine since it is more common than vulpina! Also look at the characturistics above. I have seen this "2 toned" coloration before and thought it was very different thn the vulpina's i was used to in the pacific NW. I think this is a great characturistic for identifying alpine! also look at the branching and overal color.
another note found..
Based on morphology and distribution, material of L. vulpina s. lato from the Sonoran region appears to include both L. vulpina s. str. (especially near the coast, and similar to European material) and the L. 'lupina' (especially away from the coast, and yellower, more highly branched, and with larger and more diffuse soralia) morph of Kroken and Taylor (2001). However, in my opinion the differences between these two morphs, as given by these authors and by Goward (1999), are not very consistent and are difficult to apply to the often poorly developed specimens found in southern California, where the distributions of the two morphs overlap. A few specimens from the San Gabriel Wilderness are much more robust and have sparsely divided main branches 2-3 (-7) mm wide with narrow branches mostly in the upper parts; in these morphs the narrow branches are either divaricately branched in scattered dense clusters, or more parallel and sinuous and concentrated towards the tips with extensive coverage by isidioid soredia concentrated on these smaller branches. These and other populations from arid areas may represent additional species (Barreno, pers. comm.).