Peltigera neopolydactyla is the first Peltigera that I ever positively identified, which isn’t surprising since it is the most abundant hairless (glabrous) Peltigera west of the Cascades. It has many common names; felt lichen, frog pelt, undulating pelt, and carpet pelt to name a few. The funny thing is that all these pelts make one think of a skin, and they certainly look the part, but the pelt in Peltigera is Latin for shield. Personally (and privately up until now) I think of all Peltigera as frog pelts.
There were two events that awakened my interest in lichens. The first was making a comment to Craig Sondergaard about all of the bird poop on a sidewalk we were next to, and him telling me those round white patches were a living organism, a lichen of some sort. I had never seen a living thing that seemed so lacking in life!
The second was a few weeks later, when I found several Peltigera near the Oregon Coast, which may have been P. neopolydactyla, although I can’t say for sure since I only had some poor cell phone photos with which to compare. The color and texture and those wild apothecia thrilled and fascinated me.
So I bought ‘Macrolichens of the Pacific Northwest’ (McCune/Geiser). A few days after I got it I found a patch of this lichen on the Kalama River and knelt next to it, book in hand, peering through a hand lens I’d scavenged from some broken binoculars, in a soaking rain, until I knew what it was. I’ve been hooked ever since.
Description-Thallus foliose, large, glabrous , light to dark shades of grey and/or brown; large (25-40mm) rounded lobes; apothecia brown, arising from narrow lobes; lacks soredia, isidia, and lobules; margins downturned; rhizines mostly unbranched, up to 10mm long; ventral veins broad and low.
Similar species-While a hand lens is not strictly necessaryfor differentiating Peltigera, a key (like this one) of some sort is necessary, because there are varying combinations of characteristics. P. membranacea, canina, praetextata have tomentose (hairy) dorsal surface, at least toward the margins; P. collina is often epiphytic, has soredia, and has black apothecia; P. pacifica has many lobules on the margins; P. polydactylon has much narrower lobes; P. membranacea has narrow, threadlike, erect tomentose ventral veins; P. canina has bushy rhizines.
Habitat– On soil or moss, or either over rock, rotten logs or stumps, in mostly shaded, moist woodlands.
Range– Holarctic ; Region wide in appropriate habitat; most common west of Cascades; only found in damp, wooded areas on the eastside.
Eaten by– Various slugs and snails.
Etymology of names– Peltigera translates from Latin as ‘shield bearer’, and refers to the shape of the thalli in many members of this genus. The specific epithet neopolydactyla refers to this lichen being like a ‘new polydactylon ‘. That specific epithet means ‘many fingers’, which refers to the narrow ‘finger’ lobes from which the apothecia arise like fingernails. Many thanks to Bruce McCune for telling me that this epithet alluded to the narrow lobes supporting the apothecia.
Peltigera neopolydactyla – Common Macrolichens of the Pacific Northwest