Hypogymnia Inactiva

Day 106: Just as I was about to start celebrating a second location for a different Hypogymnia ("tube lichen"), I said to myself, "Hang on a mo'...the medullary ceiling was dark, not white. That means it's..." (I grabbed the 40-pound field guide) "...it's inactiva." The narrow-lobed Hypogymnias are easy to confuse without that crucial datum, so I was glad I'd checked. No, I honestly don't have all the information committed to memory. I rely on books and other resources almost on a daily basis, whether it's for lichens or vascular plants. That said, there are different things to check for between genera in the field, e.g., presence and type of fruiting bodies, branching, base colour, whether a podetium (stalk) is hollow or solid, and those are the things I keep in mind when examining a specimen. Even then, it's all too often that I won't be able to differentiate species simply from macroscopic characteristics. If I can get "close enough for gov'mint work," I'm happy. With Hypogymnias, one of the most helpful field identification points is the colour of the medullary ceiling, so when I found this one, I pinched off one small lobe and peeled it apart. Hypogymnias are called "tube lichens" for a good reason. Their lobes are hollow, like balloon animals. Separate the blue-green top from the black lower surface, and the telling point will be what colour is on the inside of the top layer. If anyone had been close by, they would have heard me apologize, "Sorry, sorry. I can't tell who you are without doing this. Sorry!" as I nipped off an inch with my thumbnail. Yes, seriously.

Totally Tubular Transplant

Day 21: Tube lichens are among my favourites. Why "tube?" The lobes of Hypogymnias are like little balloons, inflated, generally black on the bottom and pale green on top. One of the steps in differentiating them is to peel the two surfaces apart in order to examine the underside of the top layer (the medullary ceiling). Its colour can be helpful in distinguishing species. According to Bruce McCune, "Students of Hypogymnia are frequently seen popping open lobes to check for the white interiors of H. imshaugii versus H. inactiva" (the specimen in the photograph above). It is one of the most common Hypogymnias in the Pacific Northwest. Occasionally when I'm out hiking in an area where collection is allowed, a forlorn, fallen clump of lichen will follow me home like a stray kitten to be transplanted to a suitable substrate in my yard. I hope H. inactiva likes old cedar fencing.

Separating The Sheep From The Goats

Day 105: While it's actually quite easy to distinguish Evernia prunastri (top) from Hypogymnia inactiva (bottom) using only field characteristics, many lichens require reagent testing to achieve an accurate identification. Since some of the reagents commonly used have a shelf life of mere minutes, the amateur lichenologist is at something of a disadvantage. We often resort to placing "sp." ("species") at the end of the scientific name (as in "Hypogymnia sp.") when we are unable to test our specimens or narrow an identification down by location or substrate. That's "close enough for government work" when you don't have laboratory faciilities available.

"Inactive" Lichens

Day 132: In another venue, the lichen photo I posted yesterday sparked quite a discussion of where the "inactiva" part of the scientific name originated (Hypogymnia inactiva is also called "Inactive Tube Lichen" in some references, but Brodo is the recognized authority, so I have used "Mottled Tube Lichen" as the common name). I did some digging and found out that "inactive" lichens are those which can survive long periods of dry and/or cold weather. Growth ceases during stressful conditions and resumes only when sufficient warmth and moisture are available. It is always good to understand the taxonomy.

Here is another specimen of Hypogymnia inactiva showing the typical brownish-yellow apothecia fully open. It is growing on a downed limb of Red Alder (Alnus rubrum).

Mottled Tube Lichen, Hypogymnia Inactiva

Day 131: I've made at least three attempts at capturing the beauty of this particular specimen of Hypogymnia inactiva with the little Sony point-and-shoot camera I carry on my belt while walking. I couldn't get the depth of field right, and the camera wouldn't register true color. After another failure today, I decided there was nothing for it but to throw the tripod over my shoulder and the "real" camera (the Canon SX30 IS) around my neck and take a second walk. Yes, I could have found another example closer to home because Mottled Tube Lichen is very common in the mixed forests at this elevation, and in fact I did take photos of another specimen with open apothecia. Although this isn't a "field guide" shot, it has greater eye appeal. Common though it may be, Hypogymnia is one of my favorite lichens.