You know it’s May at my house when the Fragile Forktails start flying

Exactly five years to the day after I found my first Fragile Forktail damselfy (Ischnura posita) in the back yard, this morning I found another one:

Fragile Forktail (Ischnura posita). Boca Raton, FL, May 10, 2017.

After looking through the archives of this site, it certainly seems that May is the month for these little guys. Nearly every year it seems I'm posting a mention or a photo of them in this month, and very rarely in any other. Now if only I could regain my steady hands from a couple of years ago; most of my recent photos are much blurrier than they should be. Sigh...

Indigoberry, bees, and spiders

One of my favorite Florida native plants is White Indigoberry (Randia aculeata). It forms very dense shrubs that can be trimmed up to look like small trees with effort (and luck). The flowers and fruit are both white (hence the White in the common name), and when you break the fruits open, they're very dark purple inside (hence the "Indigo"). The leaves are shiny, and in the spring, when they're flowering, they can attract tons of pollinators. I've seen several species of butterfly slurping down the nectar, a couple of different flower flies (Syrphidae), and of course, the omnipresent honey bee (Apis mellifera). Right now, it's flowering, and the bees are taking their work very seriously:

Honeybee on White Indigoberry flower. Boca Raton, FL, May 9, 2017.

So, too, are the spiders:

"Crab" spider (Gasteracantha cancriformis) and honeybee. Boca Raton, FL, May 9, 2017.

I suppose it's appropriate that these spiny-backed orbweavers are tending to the sometimes spiny White Indigoberry.

Sanderlings are media savvy, I guess

There was a daring flock of Sanderlings at Red Reef Beach this afternoon, darting in and out of the waves, barely ruffling their feathers when people would stroll down the beach. (They did all take flight simultaneously when a Fish Crow flew over testing its luck.) You'd never know the flock was there from my ability to document it, though. This is the best of the very few photos I was able to take:

Sanderling, Red Reef Beach

A few minutes later, the entire flock of at least a dozen birds moved to within three feet of me to mock me. They knew, with the instinctive knowledge that birds have, that I was currently seeing this message on my camera/phone:

Dainty sulphur butterflies are back.

Well, I don't know whether "they're back" is the right way to put it. After all, I'm the one who's back. After being buried under my desk for the past couple of weeks, I was finally able to poke my head outside my office with my camera one afternoon this week. And, despite it being a blustery afternoon (they always are—morning is the only consistently good time for butterfly and wildflower photography), one of the pictures I took got most of the beast in focus! (Click on the image for the full-size version; the one on my screen looks fuzzy. It's not, I promise!)

Dainty Sulphur (Nathalis iole) buttefly. Boca Raton, FL, May 3, 2017.

Signs of spring: cardinal egg on the ground

It rained last night, and this morning I found a cardinal's egg on the front lawn. Not sure how related those two events are. I've been seeing lots of territorial behavior in the neighborhood avifauna lately.  

Northern Cardinal Egg, Boca Raton, FL, May 3, 2017

It might not show up on the 300-pixel-square image above, but if you click the picture, it'll take you to the full-size capture from my phone. I kind of like the moisture beads on the shell.

Little Blue Dragonlet on the last cool morning of the spring

On what was probably the last cool morning of the spring here in south Florida, a Little Blue Dragonlet was resting on the Bahama Senna along my driveway:

Little Blue Dragonlet (Erythrodiplax minuscula). Boca Raton, Florida, April 26, 2017.

Its body was covered in dew, too cold to move, so it was much more still than these guys usually are when I get this close with the macro lens. You can even see traces of condensation on its right forewing, outlining some of the intricate venation of a dragonfly wing.

Giant Trees

On a recent trip to New York City, the boys and I wandered through the American Museum of Natural History, inspecting the dinosaurs on the fourth floor, the Hayden planetarium over on the other side of the building, and a few of the points in between. One of the sights I found most interesting was the huge cross section of a giant old sequoia (Sequoiadendron giganteum) in their "ecosystem" section:

The Mark Twain cross section at the AMNH. Photo by Matthew G. Bisanz from Wikimedia commons.

Unfortunately, because I don't know how to manage my iPhone storage, I was unable to take a picture myself (hooray, 16GB of "storage"!), so I had to use the one above from Wikipedia. It doesn't really have the impact that the huge piece of wood had on me. Here's an image from a National Geographic archive that really gets across the idea of how big this thing is:

Loggers with the freshly felled Mark Twain tree, 1892.

I was so impressed by this piece of wood that when it came time to plan our annual pilgrimage to California, we decided to visit the much-more-crowded southern Sierra instead of the eastern side, where we normally go. For the past several years, we've been going to the park at the Ancient Bristlecone Pine Forest. Those trees, growing at 10,000+ feet of elevation, are much smaller than the giant sequoias but also much older. Some of them are over 5,000 years old. But they don't make as much of an impression on the younger crowd as they do on me. So this year, it's time to visit the real giants. And when we do, we won't forget to walk the Big Stump Trail! Interesting note about the wood of these giant trees: at the same time, it's soft, brittle, and highly resistant to rot.

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.

Christmas Eve birding in Texas

The family went west for Christmas this year, but only halfway. Spent the holiday just east of Dallas with family. Here are a few birds from Christmas Eve at the lake house and the farm:  

Flower spiders: Thomisidae

There are many genera of crab spiders (also known as flower spiders) in the family Thomisidae. One of the more common in my yard is (I think) in the genus Mecaphesa (but here's a good illustration of why I'm not positive about the ID). Like most crab spiders, these have a very variable appearance. In fact, they are able to vary their appearance to match the background against which they appear; it takes a bit of processing to get them to show up well when they're photographed in situ. I've written about these spiders before, but I saw one the other day and happened to have my camera with me, so I thought I'd at least take a picture:
Crab spider. Boca Raton, FL, September 29, 2016.

Thomisid (crab) spider. Boca Raton, FL, September 29, 2016.

As you can infer from the photo, they're quite small; the dune sunflower that it's perched on is only a couple of inches across. Not a threat to humans, although it might provoke startlement and wonder from any who happen to notice the little feller. However, when we zoom in on their scale, they start to look a bit more daunting:
Thomisid spider, close-up. Boca Raton, FL, September 29, 2016.

Thomisid (crab) spider, close-up. Boca Raton, FL, September 29, 2016.

As you can see, their front two pairs of legs are MUCH longer than the middle or hind pair. These ambush predators rely on those long front legs to seize their prey rapidly, then they use their chelicerae (fangs) to inject venom to finish them off. According to the University of Kentucky web site about crab spiders,
Scientists think that the venom of certain crab spiders is more potent than that of most other spiders: this allows crab spiders to quickly paralyze the large and tough bees that often visit flowers.  However, crab spider venom is not known to be especially dangerous to humans.
In case you're wondering, the not "especially dangerous to humans" doesn't mean being bitten wouldn't hurt. It just means that you'll probably feel, at most, an "ouch!" and some slight muscle cramping (to paraphrase Rod Crawford's description of the typical response to Tarantula bites). This bears remembering. We live in such a sanitized world, so far removed from an everyday experience of nature, that any reminder of it (lizards, snakes, spiders), or even the possibility of slight discomfort caused by it, sends shudders of revulsion down our spines. Like any wild animal, spiders should be treated with caution and as much knowledge as we can bring to bear on them. The more we know about them, the less frightened of them we need to be. If you're a caterpillar, on the other hand, go ahead and be frightened. If you're not wary, you are in for a rough time, as this "orange dog" (Giant Swallowtail cat) found out a couple of years ago:

Know before you go! Disguises and chemical defenses and living on a spiny plant only take you so far in life...

Etymology It's entirely plausible that the name of this family of spiders derives from the Greek word thôminx, "string." The suffix -idae is the typical New Latin suffix appended to the name of any organism to indicate that it is belongs to that taxon. (For example, gulls are "larids," meaning they're in the family Laridae.) However, the Century Dictionary, my go-to dictionary for etymology, gives a slightly more interesting derivation from its definition of Thomisus (the original name of a genus of this family): whip, scourge! screen-shot-2016-09-30-at-10-52-43-am
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