A common lichen of Florida scrub: Powder-puff deer lichen

When walking through the sandy scrubby areas at my two favorite natural areas here in Boca Raton (Yamato Scrub and Pondhawk), if I keep my eyes on the ground I can usually rely on encountering a fine group of reindeer lichen like this one:

Reindeer lichen (Cladonia evansii), Yamato Scrub, January 19, 2017.

But just what the heck are reindeer lichen? While I've known about this species (we'll keep it simple and just call the symbiont a species) for at least a decade now (first encountered in my field classes from the Florida Master Naturalist Program), I'd never done much research on it. After encountering this beautiful reindeer lichen at Yamato Scrub this past January, though, I decided to correct this deficiency in my education. About the only bit of knowledge I have about lichens is that they are a symbiotic association of (usually) a fungus and an alga. So, yes, when a fungus and an alga take a lichen to one another, something wonderful happens. [crickets chirping] However, when I began reading about lichens, I soon realized why I'd not put much effort into it before: the literature devoted to them is for specialists indeed! So, after quite a bit of reading, here's what I've found. The typical association of the organisms found in lichens is a fungus (which provides the structure or body of the lichen) and an alga (which provides the color). In technical terms, when found in lichens, the fungi are mycobionts and the algae are photobionts. Fungi derive all their nutrients from their substrate, while algae are capable of deriving energy directly from sunlight (through photosynthesis). The association works quite well, although the resulting organism is rather pollution-intolerant. Lichens are thus indicators of good air quality. (Hmm... Corals are also symbiotic organisms, and their fragile nature serves to indicate the health of marine waters. Maybe there's something to this ecosystem idea.) In any case, one of the things that makes lichens interesting is that the different species are linked together by their mode of nutrition, not their ancestry. Apparently, it's customary to name the lichen by the taxonomic name of the fungal part, ignoring the alga's contribution to the affair. Most people who have noticed lichens have probably seen them as spots or flakes of color on tree trunks or on rock surfaces:

Lichen on cabbage palm. Yamato Scrub, January 25, 2017.

Some lichens, though, appear to grow directly on the soil. And such is the case with Cladonia evansii, the powder-puff deer lichen. Here, for example, is the brief description of the genus to which this species belongs in the most recent taxonomic work I could find ("Field oriented keys to the Florida lichens," by Roger Rosentreter, Ann M. DeBolt, & Barry Kaminsky). I've highlighted in red the terms and concepts I'd never seen before in my life (notes are from various sources, chiefly here):
Description: Consisting of two parts, squamulose1 primary thallus,2 and an erect fruticose structure called podetia.3 Squamules small to medium. Podetia small to large. Pale greenish- gray to white to yellowish upper surface. Apothecia4 or soredia5 present. Never isidiate.6 Apothecia brown or red or tan. Spot tests7 various. Unique features: Sometimes intricately webbed as in C. evansii.
So you see, it's as simple as that. Fortunately, Green Deane over at eattheweeds.com has a good write-up of C. evansii here, including the various ways people have prepared it for eating and drinking, in case you need a break from the technical jargon (I know I do!). The U.S. Forest Service has a very long page devoted to the Cladonia group of lichens, although they don't include the southern-dwelling C. evansii in the list (they focus on its northern cousin, C. rangiferina). What they describe, though, helps me wrap my head around the anatomy of the lichens in this group.  From their write-up of Cladonia:
The lichen body, or thallus, is a composite structure of fungal and green algal cells. The primary reindeer lichen thallus is prostrate and squamulose (comprised of scaly, flaky, rounded pieces). The secondary thallus (podetium) is more conspicuous, being upright and fruticose. Fruticose forms are three-dimensional and have been described as shrubby and/or stringy. Podetia are hollow, highly branched, and capable of trapping wind-blown algae. They grow upward at the tip and die back at the base, similarly to sphagnum and other mosses. The spore-producing fungal bodies (apothecia) are produced at the tips of the podetia.
Anyway, what we need to know here is that the puffy part of the powder-puff deer lichen is the secondary thallus or podetium. It's the rounded bit that forms the powderpuff part of the organism. The primary thallus is the horizontally growing inconspicuous bit. Other lichens have other growth forms: folicose (leaf-like, as in the lichen on the cabbage palm near the top of this post); fruticose (shrubby), like the one we're talking about here; and crustose (crusty). Here's a close-up of one of the clumps where you can get a better view of the podetia, so you can see how they grow in an "intricate web" as noted by Rosentreter and colleagues:

Reindeer lichen (Cladonia evansii), Yamato Scrub, January 19, 2017.

There's a related species of lichen here in Florida, Cladonia subtenuis, that looks very similar, but the tips of the fruticose bits are less compact. A third species, C. perforata, also exists here and is endangered. It's restricted to the high, well-drained sands of rosemary scrub in Florida; I suspect it exists on some sites here in southern Palm Beach County, but I haven't found it yet—the closest known site is Jupiter Ridge Natural Area. According to an information page from the Archbold Biological Station, "C. perforata was the first species of lichen to ever become federally listed as an endangered in the United States. C. perforata differs developmentally from other fruticose lichens, by having its branches derived from spore-producing structures called apothecia, rather than from the primary body (USFWS 1999)." Lichens tend to grow on trees or rocks or in areas that are, at least seasonally, so hot, sterile, dry, or otherwise inhospitable that nothing else can make a go of it. In polar and subpolar areas, they can even comprise the dominant autotroph (self-feeding organism, usually translates as "plant," although only the algal partner in a lichen can be considered a plant in any strict sense). In this case, they actually grow on the sand. Or, actually, on a soil crust. What's a soil crust? Well, my friend, that is a deep rabbit hole indeed. If you're going to go down there, here is a description from the Archbold Biological Station's website (emphasis added):
Biological soil crusts. In drier regions of the world, soil microorganisms form what are known as biological soil crusts. Because of their hidden nature, these crusts have been termed cryptogamic, cryptobiotic and microbiotic. Crusts are created when soil organisms cause the uppermost layer of soil to solidify into a single, cohesive layer. The "glue" that holds the soil together is made up of the living organisms themselves together with the sticky substances they excrete and leave behind as they move through the dry soil. Biological soil crusts are a well-known feature of deserts in the southwestern United States and have only recently been recognized in the southeast. Crusts in Florida scrub are unique because they occur in a wet climate where dry conditions are caused by rapid drainage of water through sandy soils.  
See how far a simple nature walk can take you? I'll have to read a lot more about soil crusts before I can do justice to them here.

Dragonflies gone missing?

Carolina Saddlebags (Tramea carolina). Boca Raton, FL, September 5, 2015.
I haven't seen nearly as many dragonflies in the back yard this summer as I have in years past; I'm not sure why. But it seems that nowadays I have to travel if I'm to see anything like the diversity or abundance of species I'd enjoyed in my back yard for the four years we've been in the new place. So the Saturday morning of Labor Day weekend I went to Yamato Scrub, camera in hand, hoping to score an odonate fix. I managed to find quite a few, as well as some lovely little butterflies. As usual, I saw many more than the few who cooperated for the camera. Here are two, one each from the dragonfly and damselfly groups. First, the lovely red dragonfly Tramea onusta, called the Red Saddlebags (there is a Carolina Saddlebags as well; almost indistinguishable except that the black spots on the tail in Red are only on top, whereas in Carolina, the black goes all the way down the sides):
Carolina Saddlebags (<em>Tramea carolina</em>). Boca Raton, FL, September 5, 2015.

Red Saddlebags (Tramea onusta). Boca Raton, FL, September 5, 2015.

And here's a damselfly. This one's a bluet, I suspect Atlantic (Enallagma doubledayi), but I can't rule out Familiar (E. civile) without having the specimen in hand and an argument with specialists:
Bluet damselfly, probably Atlantic (<em>Enallagma</em> sp.). Boca Raton, FL September 5, 2015.

Bluet damselfly, probably Atlantic (Enallagma sp.). Boca Raton, FL September 5, 2015.

I think the broad bar of blue connecting the "eyespots" (called postocular spots by specialists) on the back of the head argues strongly in favor of Atlantic over Familiar, but it's by no means conclusive. Here's the bit I'm talking about:
<em>Enallagma</em> eyespots with broad blue bar connecting them.

Enallagma postocular eyespots with broad blue bar connecting them.

According to Paulson, who wrote the book on these bad boys, "postocular spots larger in Familiar and without occipital bar, but overlap." Bonus picture: Ceraunus blue butterfly, Hemiargus ceraunus:
Ceraunus blue (<em>Hemiargus ceraunus</em>). Yamato Scrub, September 5, 2015.

Ceraunus blue (Hemiargus ceraunus). Yamato Scrub, September 5, 2015.

I love how the blue in the tailspot lights up so brilliantly in the right light. References Paulson, D. R. 2011. Damselflies and Dragonflies of the East. Princeton: Princeton UP.    

Here there be dragons

Wow, a record for me. Three days in a row at the Yamato Scrub! My older son, Eric, surprised me midmorning on Labor Day by suggesting that we go to Yamato Scrub. I seized on the suggestion, and off we went. I brought snacks and a drink to keep him occupied, and it worked! I was able to install him on a bench with a good view of the pond while I wandered off to take a few more pictures of the insect life around the wetlands, and found some new (to me) creatures and behaviors. It wasn't long before he grew hot and bored and "suggested" that we head home, but when a place is this teeming with life, it doesn't take long to get some pictures of it, either. One of the more common insects around the pond at this time of year is a tiger beetle; I'm not entirely sure which one it is, but I believe it to be the punctured tiger beetle, Cicindelidia punctulata. There are dozens, if not hundreds, of them flying around from spot to spot around the sandy margins of the wetlands, so if I get back there anytime soon I'll be sure to take more photos to get the ID. Here's the one shot from this trip that sort of turned out:
Tiger beetle, presumed Cicindelidia punctulata. Yamato Scrub, September 1, 2014

Tiger beetle, presumed Cicindelidia punctulata. Yamato Scrub, September 1, 2014

While not as showy as other tiger beetles (seriously, do an image search on tiger beetles and you'll see some amazing walking jewelry), it has a certain charm in the metallic sheen from its hard wing covers (elytra). Tiger beetles, true to their name, are predaceous, using their impressive speed, large eyes, and hefty mandibles to attack and consume their prey. I haven't seen them catching or eating anything, but by all accounts, it's impressive. However, and as sort of a follow-up to yesterday's post that featured a damsels in distress (that is, a damselfly eating another damselfly), today's post features a truly impressive feat of predation: a dragonfly, Eastern Pondhawk (Erythemis simplicicollis) feasting on another dragonfly, Blue Dasher (Pachydiplax longipennis):
Eastern Pondhawk (Erythemis simplicicollis) enjoying a repast of Blue Dasher (). Yamato Scrub, September 1, 2014.

Eastern Pondhawk (Erythemis simplicicollis) enjoying a repast of Blue Dasher (Pachydiplax longipennis). Yamato Scrub, September 1, 2014.

It was a bit windy, and I couldn't get as close to the subjects as I'd have liked, so the picture's a bit blurry, but it's pretty easy to see what's going on here. Like any good predator, the pondhawk here is feasting on the tastiest bits of its captured prey first—in this case, the face and brains. The dragonfly that's being eaten is a bit blurry in the shot above, so here's a shot of one of its brethren (who knows? maybe it's the exact same animal, as I didn't follow this one after I'd photographed it) displaying the same markings on its tail (what dragonfly people call its "abdomen") and thorax (that part of the insect where the four wings and six legs attach):
Blue Dasher (Pachydiplax longipennis), Yamato Scrub, September 1, 2014.

Blue Dasher (Pachydiplax longipennis), Yamato Scrub, September 1, 2014.

Come on out to the Yamato Scrub if you want to see some amazing examples of nature, "red in tooth and claw." Because, unlike on the maps of antiquity or the Renaissance, here indeed, there be dragons. (Well, dragonflies, at any rate.) And tigers. (Well, tiger beetles.) Etymological note: the genus of the tiger beetle pictured at top (Cicindelidia) appear to be derive its name from the latin word for glow-worm, cicindela. (There are two North American genera with similar names, Cicindela and Cicindelidia; presumably they are named so similarly because they are suspected to be closely related.) Tiger beetles do have a bit of a metallic sheen to them, which might account for the genus name, but I really have no idea...

Damsels in Distress

You may remember that I volunteer with the Palm Beach County Department of Environmental Resource Management from time to time, helping them clean up and maintain the natural areas here in Boca Raton. Last weekend there was a work party at Yamato Scrub, and we were there for sunrise, coffee, donuts, muffins, and—oh, yeah—work. We trundled wheelbarrows full of sand from the sand mound to a few areas of sidewalk between the two recreated wetlands on the site. There’s a sand berm between the northern pond (the deep one) and the southern wetland (much larger and shallower). When the rains come, the sand next to the sidewalk tends to follow the water downhill, leaving the sidewalk higher and drier, which will eventually cause the sidewalk to fracture and degrade. So our work party helped to shore up the sand around the sidewalk, delaying the inevitable for another few seasons. We also did the traditional work party routine: trash pickup, with long-handled grabbers and trash bags, cleaning up as much of the area as we reasonably could. You always find the usual stuff that people discard (cans, bottles, wrappers, shotgun shells), but you're also always on the lookout for the fun stuff. For example, when we did the planted area in the parking lot, my covolunteer Dan found the weirdest object I’ve yet seen: a fully inflated toddler’s waterwing. What on earth was that doing in the parking lot of a scrub area? As we were taking trash from around the perimeter of the wetlands, we ran across some pretty blue flowers, which our ERM coordinator ID’ed for us as Blue Curls (Trichostema dichotomum); I was able to snap a decent image with my iPhone and its little Olloclip macro lens:  
Blue curls (Trichostema dichotomum</em.). Yamato Scrub, August 30, 2014.

Blue curls (Trichostema dichotomum

We also ran across some hogplum (Ximenia americana) in flower; the contrast between the delicate blooms and the long, wickedly sharp thorns, never ceases to impress me (particularly when I get too close!). I couldn't get good focus with the iPhone, so here's a shot from the next day with my real camera:
Hog plum (Ximenia americana). Yamato Scrub, August 31, 2014.

Hog plum (Ximenia americana). Yamato Scrub, August 31, 2014.

Of course, during a work party I can’t exactly tote around my real camera and rig, so the iPhone photos just serve to remind me of what’s there until I can get back to the site with my DSLR and its macro lens to do some real “work.” For example, here's a shot of the blue curls taken with my Nikon instead of my smartphone:
Blue curls (Trichostema dichotomum</em.). Yamato Scrub, August 31, 2014.

Blue curls (Trichostema dichotomum

Nice to get some focus across the entire image! In fact, the main reason I went back to the site the day after the work party was that while we were working, I noticed some damselflies that intrigued me—spreadwings of some sort, but without my macro lens, I wasn’t able to get a sharp enough picture to ID them. So I returned the next day with my real camera and set about hunting them down. Turns out I wasn’t the only hunter in the wetlands: this enterprising Rambur’s Forktail (Ischnura ramburii) captured an unwary (or just unlucky) Atlantic Bluet (Enallagma doubledayi).
Rambur's Forktail breaking its fast on Atlantic Bluet. Yamato Scrub, August 31, 2014.

Rambur's Forktail breaking its fast on Atlantic Bluet. Yamato Scrub, August 31, 2014.

Damsels in distress, indeed! The fork tail in the picture above is spreading its wings, but only to keep its balance and flight-readiness; when resting normally, it folds them over its back, like so:
Rambur's Forktail (Ischnura ramburii). Yamato Scrub, August 31, 2014.

Rambur's Forktail (Ischnura ramburii). Yamato Scrub, August 31, 2014.

Here's a closer look at her enjoying her breakfast:
Rambur's Forktail (Ischnura ramburii) and breakfast. Yamato Scrub, August 31, 2014.

Rambur's Forktail (Ischnura ramburii) and breakfast. Yamato Scrub, August 31, 2014.

After some hide and seek, I was able to relocate some of the spreadwings and, as I might have expected, they’re the only species we have here in Boca as far as I know: Carolina Spreadwing, Lestes vidua:
Carolina Spreadwing (Lestes vidua). Yamato Scrub, August 31, 2014.

Carolina Spreadwing (Lestes vidua). Yamato Scrub, August 31, 2014.

Carolina Spreadwing (Lestes vidua). Yamato Scrub, August 31, 2014.

Carolina Spreadwing (Lestes vidua). Yamato Scrub, August 31, 2014.

But when you're intent on hunting down one particular insect, there might be others who are just as intently trying to hunt you down!
Biting fly, Tabanid family. Yamato Scrub, August 31, 2014.

Biting fly, Tabanid family. Yamato Scrub, August 31, 2014.

A word of caution if you plan to hang out in the wetlands: there are plenty of predators on the wing! For example, a few dragonflies (top, Little Blue Dragonlet, Erythrodiplax minuscula; Middle, Common Green Darner (Anax junius); bottom, unidentified. Erythrodiplax_minuscula_YS_20140831 Anax_junius_YS_20140831 Dragonfly_YS_20140831 And if you're the first one on the trail, you might find a few roadblocks put up by other kinds of predators, like this spider (I think it's the tropical orb weaver, Eriophora ravilla, but I'm not sure):
Orb weaver. Yamato Scrub, August 31, 2014.

Orb weaver. Yamato Scrub, August 31, 2014.

You need to look sharp if you don't want to walk out of the scrub wearing spider silk! Now, if only those biting flies had been the bugs that these spiders were eating... Oh, well.

Preemptive strike

Last year I ran across a pair of walking sticks (Anisomorpha buprestoides) during an afternoon stroll at Yamato Scrub. They were in such a visually striking pose that I had to stop and take a picture, and then read what I could find about them on the web. And it made for some interesting reading. Since then, though, I've been doing more reading, and at a more leisurely pace. One of my favorite reads came from the shelves of the Broward county library: Thomas Eisner's For Love of Insects, which I checked out over the summer and promptly devoured. Since then, thoughts of walking sticks hadn't really crossed my mind, although on one of my evening rides with the boy, we saw several pairs of these creatures crossing the bike path of the El Rio Canal, from a scrubby vacant lot headed to the grass bordering the canal. I wish I'd had time to stop and watch them, but the sun was sinking and the boy doesn't watch himself, so I have to... Off we went, accompanied by the sound of my mental sighs. Then, earlier this week, when I was in Manhattan after a hastily arranged business meeting, I found a copy of Thomas Eisner's book at the Strand, and it practically leapt off the shelf into my shopping bag. As I reread it, I wondered at how I could have ever forgotten that Eisner's favorite place on Earth appears to be Florida Scrub! I guess I was too busy trying to absorb the chemistry and entomology of the book, neither of which is particularly demanding. (If you haven't read this book, you should; it reads almost like a memoir, and it presents a decidedly difficult-to-love group of animals in a singularly appealing style.) One of the first anecdotes Eisner tells about his entomology expeditions at Archbold Biological Station is about the walking stick, also known as devil's rider, A. buprestoides. These strange creatures have some unusual behaviors. For example, they discharge a potent defensive chemical when handled roughly by humans; they even appear to aim it toward the eyes. What's more, these insects that defend themselves only after being handled roughly by humans actually change strategies when confronted by potential predators like Cyanocitta cristata, our familiar eastern Blue Jay. Instead of waiting for the insult, as they do with us humans, the insects spray preemptively when confronted by birds! In other words, somehow these little creatures can discriminate nicely between the threat posed by humans and that posed by potential predators, and they don't let the potential predators come close to them. According to Eisner,
I never figured out what it is about a bird that makes it recognizable as such to the walkingstick. It is clear that no crude combination of vibrational and visual cues is involved. I tried to elicit discharges by waving objects in the vicinity of walkingsticks, or by tapping the substrate around them, but without success. Anisomorpha evidently is programmed not to waste its secretion, and to fire only on "the real thing." (86)
Now that is something unusual in the world. The chemical, a terpene, is actually synthesized inside the insect's body, rather than being incorporated into it ready-made from its larval diet, as with the milkweed caterpillars (Danaus, Limenitis, etc.). At the time of Eisner's research, the question of whether or not insects could manufacture their own chemicals, or whether they had to acquire them ready-made, had not yet been answered, so this was important confirmation of insects' chemical manufacturing prowess.

Opus, opuntia, opunt

Opuntia cacti are a successful and widespread family in the group Cactaceae, but they are not all that well understood. My first introduction to the group was as a child, when I blundered into one of them on one of those weekend fishing trips in Colorado that we took quite frequently in my salad days. I'm sure you can guess the results: bloody socks, screams of bloody murder, and plenty of tears. And I'll bet that, at that tender age, I would have had no compunction about unleashing any sort of revenge on these plants, up to and including biological weapons. Monday's trip to Yamato Scrub, and my subsequent research online, gave me a new insight into these little spiny succulents. I'd always known that Florida's "native cactus" was the prickly pear, but I really had no idea how many different species of Opuntia there are (up to 200, depending on how you draw the taxonomic lines)... Read more

What’s in a name?

Really, I'm asking. What is in a name? Tarflower is a beautiful plant of Florida's scrub and pine flatland areas. It's a large wildflower or good-sized shrub in the Ericaceae, or heath, family. The flower is distinctive, with its 7 pinkish white petals, completely free (i.e., not joined together), arrayed around those central pistils. The common name gives a good idea of its strategy to deter nectar snatchers (ants, houseflies, etc., who might be tempted to take its nectar without "paying" for it--that is, without performing the pollination services for which plants evolved their nectar-facilitated reproductive strategy): it traps freeloaders with a sticky secretion from the hairs on the stems. Its scientific name, though, is a bit of a mystery. Several authorities (Taylor and Bell, Austin and Bass) call it Befaria racemosa, as does the University of Florida webpage that I link to at the beginning (the #1 Google hit for "Tarflower"). Austin and Bass go so far as to mention that the genus name is derived from the name of a Spanish officer named Bexar. Many authorities, among them the ISB website, simply correct the name to Bejaria without commentary. Other authorities, though, (e.g., W.K. Taylor) point out that Befaria is actually a mistake; the proper form of the name is Bejaria (which makes more sense if it truly is derived from Bexar). Now why such learned writers as Austin and Bass would give the "incorrect" spelling to a name that they obviously know the derivation of, is beyond me. So far beyond me, that I went straight to the source: According to the USDA GRIN Taxonomy, Befaria is a "rejected original spelling that is unavailable for use." Rejected by whom, I ask? Bejaria, on the other hand, gets the comment "this spelling conserved (nom. cons.)(Vienna ICBN Art. 14.11 & App. III) against the original spelling 'Befaria'." In other words, Etienne Pierre Ventenat named the plant according to Linnaeus's misspelled Befaria, and later on, I suppose, someone named Mutis changed it to Bejaria? Or, is Mutis just the latin for changed, and everyone knows that the spelling of the genus name was changed? To find out about the natural history of the genus, it would be hard to do better than this page from the New York Botanical Garden; if you're too lazy to click the link, here are a couple of representative sentences:
It is characterized by 7-merous flowers, free petals, capsular fruits, non-appendaged anthers, and viscin threads intermixed with the pollen tetrads.  It is sometimes considered morphologically and anatomically isolated within the Rhododendroideae.
If you're still with me, you deserve a treat, so here is a little gallery of Tarflower from the Yamato Scrub: But the question remains: what's in a name? More specifically, what's in this (generic) name? (So should I have asked, "More generically," what's in this name?)

Why Yamato Scrub? Why not?

We went to Yamato Scrub a couple of times this weekend; once very early on Saturday morning, and once again around sunset on Sunday. I just love the early morning light. Over the last year, this site really has become one of our favorite places to visit. Our first visit was back in November 2007, shortly after the place opened to the public. (Actually, all ERM lands are open to the public from dawn to dusk; it's just that the trails and parking facilities had a grand opening back in the fall of 2007, and that's what caught our attention about the site.) It's the closest spot to us where we can encounter nature in a nearly natural setting: we've had ospreys fly almost directly overhead, too close for our camera to catch the whole bird: Read more

Scrubbing, part two

As the morning wore on, the work crew wore out. The sun rose higher, the temperature followed suit, and the little pick-me-up afforded by the popsicles and other treats wore off. Good thing for this tired man that his family was standing ready to pick him up. As he returned to the truck, he phoned home to set the wheels in motion. Read more
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