Orchid Valley Natural Area

This month’s destination for the WGNSS Natural History Photography Group was Orchid Valley Natural Area in Hawn State Park. This natural area is south of the main park and not normally open to the public, but we were granted permission to enter by the park administration. Our targets were several species of orchids and other rare plants that are known to occur in the area—showy orchis (Galearis spectabilis) being the one I hoped most to see.

Image may contain: 2 people, including Ted MacRae, tree, outdoor and nature

Our group for the day (front to back): me, Lynne, David, Casey, Avery, James, Bill, and Rich (Chris behind tree at back).

There are no trails here—not even a place to park, as we squeezed our cars against the side of the road at a spot that appeared to provide good access. A bit of GPS-guided bushwhacking brought us to increasingly rough and sloping ground that ended up at the edge of a cliff overlooking one of the sandstone box canyons that this area is know for—down below was where we wanted to go. Wild azaleas lined the upper canyon edges with their stunning pink blossoms. We followed the canyon edge and found a way down, then circled back into the canyon to find a stunning waterfall, its sandstone walls dripping with mosses and ferns. We spent quite a bit of time here photographing the waterfall and surrounding area before eventually resuming the search for the orchids that we came to see.

Image may contain: plant, tree, outdoor and nature

Bill surveys a waterfall at the center of a sandstone box canyon.

Image may contain: plant, outdoor, nature and water

The waterfall fell about 25 feet onto the sandstone rocks below, its splash creating perfect conditions for luxurious growth of mosses and ferns.

Image may contain: plant, tree, outdoor and nature

Mosses sending up their “stems” (actually setae), each holding up a capsule filled with spores.

Sadly, the orchids were not yet in bloom—not even close, another victim of the cold, late spring we’ve been experiencing. Casey, our group leader, did find some very small showy orchis leaves, and we saw some nice clumps of another native orchid, rattlesnake plantain (Goodyera pubescens), an evergreen orchid that blooms during late summer. We hiked up another drainage that led to another box canyon—lacking a waterfall but equally impressive, nonetheless—but found no orchids in bloom there, either. We did, however, see cinnamon ferns sending up their spike-like fertile fronds and aggregations of antlion larvae (a.k.a. “doodlebugs”) in the soil beneath the sandstone ledges.

Image may contain: plant, nature and outdoor

Leaves of rattlesnake plantain (Goodyera pubescens).

Image may contain: plant, tree, outdoor, nature and water

Moss growth is luxuriant in the wet sandstone exposures inside the box canyons.

Image may contain: plant, tree, outdoor and nature

Sandstone ledge above a box canyon.

Image may contain: outdoor and nature

Pits of antlions, or “doodlebugs”, clustered in the soil beneath a sandstone ledge. Ants and other insects that fall into the pits are quickly dispatched by the sickle-shaped mandibles of the bug lying buried at the bottom of the pit.

You might think failure to find what we were looking for would result in a disappointing field trip—far from it! Time in the field with like-minded friends in a beautiful spot is always a pleasure, and when it comes to searching for rare plants (or insects, or whatever), failure is the norm—making success, when it does come, that much sweeter. There will be other chances to see showy orchis (perhaps in a couple of weeks).

© Ted C. MacRae 2019

Do the Doodlebug Flip

I’ve been on a doodlebug kick ever since I finally figured out how to find the little buggers on my trip down to southeast Missouri.  I even found one in one of the tiger beetle terraria that I setup with native soil brought back from that trip, so I’ll get the chance to try to rear one out.  Shortly after finding those first antlion larvae, I traveled to Rock Island, Illinois to attend the Second Illinois Hill Prairie Conference as a panelist for the insects discussion group.  During a field trip to a nearby hilltop prairie, I spotted a pit in a bed of sawdust that had the unmistakeable look of an antlion pit.  I can’t say that I’ve ever seen an antlion pit in anything but sand, so I dug up the larva to confirm that that was, indeed, what it was.  The larval pit site must have been selected by the adult female who laid the egg, so apparently the loose sawdust had the appropriate texture to induce oviposition.  The larva was fat and happy, suggesting it was feeding well in its sawdust pit.

Antlions flick sand with their head and elongated mandibles to create the pit, and they also flick it on prey that has fallen in their pit to thwart their escape.  Watch how this one also use its head flicking ability to right itself in a most humerous manner after being flipped over:

Copyright © Ted C. MacRae 2009

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl

Now you see me…

Myrmeleon_sp_P1020915_2

…now you don’t!
Myrmeleon_sp_P1020914_2

In a previous post, I lamented the fact that I had never actually seen a live antlion larva, or doodlebug (family Myrmeleontidae). Lovers of sand, I’ve seen their famous pitfall traps many times, especially in recent years as I’ve searched sand habitats for my beloved tiger beetles. Occasionally, I’ve stopped to jab my knife under a pit, give it a quick flip, and search the freshly turned sand for the maker of the pit – never seeing anything. It never bothered me much either – there were always beetles to catch!  Two weeks ago I returned to the sand prairies of southeastern Missouri to look for additional sites for Cicindela scutellaris (festive tiger beetle), and as we searched one particular site on the Sikeston Sand Ridge I once again saw the characteristic funnel-shaped pits amongst sparse vegetation in the sandy soil.  I decided this time I needed to give it a good effort – how can any self-respecting entomologist accept not having ever seen a live doodlebug?  As I’d done many times before, I kneeled down, gently put the tip of the knife about an inch away from the edge of the pit, and then jabbed its full length assertively into the sand and under the burrow and flipped it over.  Like previous times, I studied the turned sand and saw nothing.  I stirred the sand gently with the tip of the knife and studied it again – nothing.  I tried another burrow – again, nothing.  I decided right then and there that I was doing something wrong – I could not simply be picking ’empty’ pits.  I continued staring at the turned sand, and then I saw movement – I looked closer, and it seemed as though the sand itself was moving.  At last I made out its outline – I had finally succeeded in finding a doodlebug!  I dug up another burrow, and knowing what I was looking for this time I had no problem quickly locating the little creature.  I watched it as it lay motionless – perfectly camouflaged by its color and with sand grains sticking to its body, and chuckled as it buried itself almost instantly with a quick, backwards shuffle into the sand. Who knows how many doodlebugs I’d successfully dug up in the past, completely overlooking them as they lay disguised and motionless in the sand.

More than 100 species of antlions, representing at least 19 genera, live in the Nearctic Region, although much of this diversity occurs in the southwestern U.S. and Mexico.  Despite the commonly drawn association between antlions and pitfall traps, in North America only those in the genus Myrmeleon actually exhibit this behavior.  This larva dug a pit and so must represent a species of Myrmeleon – perhaps M. immaculatus, a common species in North America and one whose adult I observed last fall on a nearby sand prairie remnant.  Species in other genera have free-living larvae that hide under objects or roam underneath the sand, from where emerge briefly to hunt for prey.

For those interested in learning more about antlions, Mark Swanson has an excellent website called The Antlion Pit.

REFERENCE:

Swanson, M.  1996. The Antlion Pit: A Doodlebug Anthology. http://www.antlionpit.com/

Copyright © Ted C. MacRae 2009

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl

Lions in South Africa

Joerie, Joerie, botter en brood,
as ek jou kry, slaat ek jou dood.

Doodlebugs, joerie, shunties, toritos—these are but a few of the many colloquial names given to amusing little creatures that many people know simply as antlions (or translation of such) (Swanson 1996).   Larvae of winged insects resembling (but unrelated to) dragonflies, they are best known for their habit of digging smooth-sided, cone-shaped pits in sandy soils and concealing themselves under the sand at the bottom.  There, they lay in wait for some small, unsuspecting creature—often an ant—to fall into the pit.  When that happens, the hidden antlion bursts forth, using its oversized, sickle-shaped mandibles to “flick” sand at the prey to keep it sliding towards the bottom of the hole.  Once it is within reach, the antlion grabs the prey using those same, deadly mandibles (how delightfully morbid!).  So otherworldly is their appearance and behavior that, in addition to inspiring children’s charms, they have served as an unmistakable model for the “Ceti eels” featured in Star Trek: The Wrath of Khan!1  Adults of this group, on the other hand, have inspired far less imagination in nomenclature and culture, to the point that even their common name “antlion lacewing” is merely a reference back to their unusual larvae.  Even the scientific name of the family—Myrmeleontidae—has failed to garner complete adherence, with “Myrmeleonidae” (who needs the “t”?) and “Myrmelionidae” (perhaps from English-speakers focused on the English spelling of “lion” rather than the Latin spelling of “leo”) still appearing in popular and even scientific literature.

1 Sadly (and ironically), actor Ricardo Montalban, who played the villain Khan Noonien Singh in that movie (reprising a character he played 15 years earlier during the debut season of the Star Trek television series), died just eight days ago at the age of 88. I must confess that I am a life-long Star Trek fan (though not a “Trekkie”), and “Wrath” was certainly among my favorite of the movies, due in large part to Montalban’s steely, venomous portrayal of Kahn. My favorite line occurs as Kahn is about to put a Ceti eel in Chekov’s ear, explaining how they wrap themselves around the victim’s cerebral cortex. He then says, “Later, as they [pauses deliciously] grow…”

myrmeleontidae-larval-pitI’ve seen antlion pits on several occasions (especially in recent years as I’ve spent more time in open sand habitats searching for my beloved tiger beetles).  However, the pit pictured here—encountered at Borakalalo National Park in South Africa’s North West Province, was the first I’d ever seen in which there was actually an ant inside the pit.  The ant was dead, presumably having already been sucked dry by the joerie. I didn’t know it at the time, but southern Africa is a major evolutionary center for antlion lacewings and some of their striking relatives such as spoonwinged and threadwinged lacewings (family Nemopteridae) and silky lacewings (family Psychopsidae) (Grimaldi & Engel 2005).  Relatively few of South Africa’s antlions, however, actually dig pits—a habit restricted to species in the genera Hagenomyia, Cueta, and the cosmopolitan Myrmeleon (Scholtz & Holm 1985).  Rather, the majority of species have free-living larvae that hide under objects or roam under deep sand from where they emerge to hunt other insects.

Palpares lentusThis adult antlion lacewing came to an ultraviolet light at our encampment on the Geelhoutbos farm near the Waterberg Range (Limpopo Province). Its tremendous size and distinctly patterned wings placed it in the tribe Palparini, of which the genus Palpares is the most diverse. These are the true giants of the family, with forewing lengths that can reach 75 mm (that’s 3 inches, folks!) and both wings bearing conspicuous patterns of black and yellow markings (the yellow doesn’t show well in this photograph due to illumination by the ultraviolet light).  The larvae, understandably, are also quite large, and have even been observed to capture ground resting grasshoppers (Capinera 2008).  I sent this photograph to Dr. Mervyn Mansell, an expert on African Myrmeleontidae, who kindly identified the individual as a female Palpares lentus, endemic to northern South Africa and Zimbabwe. When queried for more information regarding its biology, Dr. Mansell responded:

We know nothing about P. lentus, except for distribution records. Nothing is known about its larva or biology, although the larvae of all Palpares and related genera are obviously large, and live freely in sand well concealed and almost impossible to find.

Palpares lentus is one of 42 species of Palparini in southern Africa—half of all known species in the tribe.  Nearly two-thirds of them are endemic to “open” biomes in the dry western parts of the subregion (Mansell & Erasmus 2002).  This high level of endemism results from the occurrence of large tracts of sand and exposed soil that are conducive to the large sand-dwelling larvae.  Eastern parts of the subregion containing forest or thicket biomes are not as favored by antlion lacewings, and consequently the diversity of species in these areas is much lower.  Because of their great size, palparine adults are especially vulnerable to predation, with the result that they have evolved elaborately patterned wings to enhance their camouflage—apparently an adaptation to the dappled shade provided by the fine-leafed plants found in these biomes.  While many species in the tribe are diurnal, a few in the related genus Palparellus pulchellus and P. ulrike are known to be attracted to light, spending the day resting concealed amongst vegetation. The attraction of this individual to our ultraviolet light suggests Palpares lentus has similar habits.

Everything you want to know about antlions can be found at Mark Swanson’s excellent website, The Antlion Pit. For information specific to Africa, Mervyn Mansell has assembled a checklist of The Antlions (Neuroptera: Myrmeleontidae) of South Africa, and a nice summary of antlions in Kruger National Park by Dave Rushworth can be found at Destination Kruger Park. I thank Dr. Mansell for his identification of Palpares lentus.

REFERENCES:

Capinera, J. L. (ed.).  2008. Encyclopedia of Entomology, 2nd Edition. Springer, Dordrecht, The Netherlands. 4346 pp.

Grimaldi, D. and M. S. Engel. 2005. Evolution of the Insects. Cambridge University Press, New York, xv + 755 pp.

Mansell, M. W. and B. F. N. Erasmus. 2002. Southern African biomes and the evolution of Palparini (Insecta: Neuroptera: Myrmeleontidae). Acta Zoologica Academiae Scientiarum Hungaricae 48 (Suppl. 2):175–184.

Scholtz, C. H. and E. Holm (eds.). 1985. Insects of Southern Africa. Butterworths, Durbin, South Africa, 502 pp.

Swanson, M.  1996. The Antlion Pit: A Doodlebug Anthology. http://www.antlionpit.com/

A sand prairie autumn

Splitbeard bluestem seed headsAsk any astronomer when autumn begins, and they will likely tell you it begins at the autumnal equinox – when shortening days and lengthening nights become equal as the sun crosses over the celestial equator. According to them, fall began this year on September 22 – at 11:44:18 A.M. EDT, to be precise. I agree that autumn begins at a precise moment, but it is not at the equinox. Rather, it is that unpredictable moment when a sudden crispness in the air is felt, when the sky somehow seems bluer and shadows seem sharper, and hints of yellow – ever so subtle – start to appear in the landscape. Butterfly pea blossomIn Missouri, with its middle latitudes, this usually happens a few weeks before the equinox, as August is waning into September. It is a moment that goes unnoticed by many, especially those whose lives and livelihoods have lost all connection with the natural world. To plants and animals, however, it is a clear signal – a signal to begin making preparations for the long cold months of winter that lie ahead. Plants that have not yet flowered begin to do so in earnest, while those that have shift energy reserves into developing seeds. Animals take advantage of their final opportunities to feed before enduring the scarcities of winter, digging in to sleep through them, or abandoning altogether and migrating to warmer climes. Insects begin hastily provisioning nests for their broods or laying eggs – tiny capsules of life that survive the harsh winter before hatching in spring and beginning the cycle anew.

Sand prairie in early September.Sand prairie in early October.  Note abundance of splitbeard bluestem seed heads.Across much of Missouri, in the Ozark Highlands and in riparian ribbons dissecting the northern Plains, autumn brings an increasingly intense display of reds, purples, oranges, and yellows, as the leaves of deciduous hardwoods begin breaking down their chlorophyll to unmask underlying anthocyanins and other pigments. Small southern jointweedIn Missouri’s remnant prairies, seas of verdant green morph to muted shades of amber, tawny, and beige. This subtle transformation is even more spectacular in the critically imperiled sand prairies of the Southeast Lowlands, where stands of splitbeard bluestem (Andropogon ternaries – above) turn a rich russet color while fluffy, white seed heads (1st paragraph, 1st photo) appear along the length of each stem, evoking images of shooting fireworks. Small southern jointweed (Polygonella americana – right) finds a home at the northern extent of its distribution in these prairie remnants and in similar habitats in nearby Crowley’s Ridge, blooming in profusion once the cooler nights arrive. Butterfly pea (Clitoria mariana – 1st paragraph, 2nd photo) blooms add a gorgeous splash of soft purple in contrast to the muted colors of the plants around them.

Kent Fothergill, Ted MacRae, and Rich ThomaAfter first becoming acquainted with Missouri’s sand prairies this past summer, I knew a fall trip (or two) would be in order. The extensive deep, dry sand barrens were ideal habitat for sand-loving insects, including certain spring/fall species of tiger beetles that would not be active during the summer months. The cooler nights and crisp air of early fall make insect collecting extraordinarily pleasurable, so it took little effort to convince friends and colleagues Kent and Rich to join me on another excursion to these extraordinary remnant habitats, along with my (then 8 yr-old) daughter Madison (who would likely characterize this as “tallgrass” prairie). Madison MacRae, age 9 (almost)I was, as ever, on the lookout for tiger beetles; however, temperatures were cool, skies were overcast, and the fall season was just beginning, greatly limiting tiger beetle activity during this first fall visit. We did see one Cicindela formosa (big sand tiger beetle), which cooperated fully for a nice series of photographs. We also found single specimens of the annoyingly ubiquitous C. punctulata (punctured tiger beetle) and a curiously out-of-place C. duodecimguttata (12-spotted tiger beetle), which must have flown some distance from the nearest dark, muddy streambank that it surely prefers. Of greatest interest, we found two specimens of C. scutellaris (festive tiger beetle), which in this part of Missouri is represented by a population presenting a curious mix of influences from two different subspecies (more on this in a later post…). Despite the scarcity of tiger beetles, other insects were present in great diversity, some of which I share with you here.

Ululodes macleayanusThis bizarre creature, sitting on the stem of plains snakecotton (Froelichia floridana), is actually a neuropteran insect called an owlfly (family Ascalaphidae). Looking like a cross between a dragonfly and a butterfly due to its overly large eyes and many-veined wings but with long, clubbed antennae, this individual is demonstrating the cryptic resting posture they often assume with the abdomen projecting from the perch and resembling a twig. The divided eyes identify this individual as belonging to the genus Ululodes, and Dr. John D. Oswald (Texas A&M University) has kindly identified the species as U. macleayanus. As is true of many groups of insects, their taxonomy is far from completely understood. Larvae of these basal holometabolans are predaceous, lying on the ground with their large trap-jaws held wide open and often camouflaging themselves with sand and debris while waiting for prey. The slightest contact with the jaws springs them shut, and within a few minutes the prey is paralyzed and can be sucked dry at the larva’s leisure.

Ant lion, possibly in the genus Myrmeleon.Another family of neuropteran insects closely related to owlflies are antlions (family Myrmeleontidae, sometimes misspelled “Myrmeleonidae”). This individual (resting lower down on the very same F. floridana stem) may be in the genus Myrmeleon, but my wanting expertise doesn’t allow a more conclusive identification [edit 4/12/09 – John D. Oswald has identified the species as Myrmeleon immaculatus]. Strictly speaking, the term “antlion” applies to the larval form of the members of this family, all of whom create pits in sandy soils to trap ants and other small insects, thus, it’s occurrence in the sand prairie is not surprising. Larvae lie in wait beneath the sand at the bottom of the pit, flipping sand on the hapless prey to prevent it from escaping until they can impale it with their large, sickle-shaped jaws, inject digestive enzymes that ‘pre-digest’ the prey’s tissues, and suck out the liquifying contents. Finding larvae is not easy – even when pits are located and dug up, the larvae lie motionless and are often covered with a layer of sand that makes them almost impossible to detect. I’ve tried digging up pits several times and have failed as yet to find one. Larvae are also sometimes referred to as “doodlebugs” in reference to the winding, spiralling trails that the larvae leave in the sand while searching for a good trap location – these trails look like someone has doodled in the sand.

Bembix americanaThis digger wasp, Bembix americana (ID confirmed by Matthias Buck), was common on the barren sand exposures, where they dig burrows into the loose sand. Formerly included in the family Sphecidae (containing the better-known “cicada killer”), members of this group are now placed in their own family (Crabronidae). Adult females provision their nest with flies, which they catch and sting to paralyze before dragging it down into the burrow. As is common with the social hymenoptera such as bees and paper wasps, these solitary wasps engage in active parental care by providing greater number of prey as the larva grows. As many as twenty flies might be needed for a single larva. I found the burrows of these wasps at first difficult to distinguish from those created by adults of the tiger beetles I so desired, but eventually learned to distinguish them by their rounder shape and coarser, “pile” rather than “fanned” diggings (see this post for more on this subject).

Stichopogon trifasciatusRobber flies (family Asilidae) are a favorite group of mine (or, at least, as favorite as a non-coleopteran group can be). This small species, Stichopogon trifasciatus (ID confirmed by Herschel Raney), was also common on the barren sandy surface. The specific epithet refers to the three bands of alternating light and dark bands on the abdomen. Many species in this family are broadly distributed but have fairly restrictive ecological requirements, resulting in rather localized occurrences within their distribution. Stichopogon trifasciatus occurs throughout North America and south into the Neotropics wherever barren, sandy or gravely areas near water can be found. Adults are deadly predators, swooping down on spiders, flies and other small insects and “stabbing” them with their stout beak.

Chelinidea vittigerPrickly pear cactus (Opuntia humifusa) grows abundantly in the sandy soil amongst the clumps of bluestem, and on the pads were these nymphs of Chelinidea vittiger (cactus bug, family Coreidae). This wide-ranging species occurs across the U.S. and southward to northern Mexico wherever prickly pear hosts can be found. This species can either be considered a beneficial or a pest, depending upon perspective. On the one hand, it serves as a minor component in a pest complex that prevents prickly pear from aggressively overtaking rangelands in North America; however, prickly pear is used by ranchers as emergency forage, and fruits and spineless pads are also sometimes harvested for produce. In Missouri, O. humifusa is a non-aggressive component of glades, prairies, and sand and gravel washes, making C. vittiger an interesting member of the states natural diversity.

Ammophila sp., possibly A. proceraThis wasp in the genus Ammophila (perhaps A. procera as suggested by Herschel Raney) was found clinging by its jaws to a bluestem stem in the cool morning, where it presumably spent the night. One of the true sphecid (or “thread-waist”) wasps, A. procera is a widespread and common species in eastern North America. One of the largest members of the genus, its distinctive, bold silver dashes on the thorax distinguish it from most other sympatric congeners. Similar to the habits of most other aculeate wasp groups, this species captures and paralyzes sawfly or lepidopteran caterpillars to serve as food for its developing brood. Females dig burrows and lay eggs on the paralyzed hosts with which the nests have been provisioned. Adults are also found commonly on flowers, presumably to feed on nectar and/or pollen.

Dusty hog-nosed snakeRich is a bit of herpatologist, so when he brought this hog-nosed snake to our attention we all had a good time pestering it to try to get it to turn upside down and play dead. I had never seen a hog-nosed snake before but knew of its habit of rolling over and opening its mouth with its tongue hanging out when disturbed, even flopping right back over when turned rightside up or staying limp when picked up. We succeeded in getting it to emit its foul musky smell, but much to our disappointment it never did play dead, instead using its shovel-shaped snout to dig into the sand. Dusty hog-nosed snake - head closeupWe had assumed this was the common and widespread eastern hog-nosed snake (Heterodon platirhinos); however, in our attempts to turn it over I noticed its black and orange checker patterned belly. I later learned this to be characteristic of the dusky hog-nosed snake (H. nasicus gloydi), only recently discovered in the sand prairies of southeast Missouri and regarded as critically imperiled in the state due to the near complete destruction of such habitats. Disjunct from the main population further west, its continued survival in Missouri depends upon the survival of these small sand prairie remnants in the Southeast Lowlands.