JIM CONRAD'S
NATURALIST NEWSLETTER
Issued from Hacienda Chichen Resort adjoining Chichén Itzá Ruin in
YUCATÁN, MÉXICO
March 18, 2012
| FIGHTING IGUANAS Visitors often photograph the Hacienda's Black Iguanas basking atop stone walls, in trees and lumbering across the ground. The other day I came upon two in the parking lot clinched together fighting, shown at http://www.backyardnature.net/n/12/120318ig.jpg. They were young ones, only about 2-½ feet long (75cm), but clearly old enough to fight. Note that both bear bloody spots on their backs behind their heads. When male iguanas do battle the main tactic seems to be to clamp down on the other's nape. We've collected a great deal of information about Black Iguanas, including a 2006 account of two large males who really bloodied one another. The fight is described on our Black Iguana page under the subtitle "Two Male Black Iguanas Battle it Out" down the page at http://www.backyardnature.net/yucatan/iguana-b.htm. ***** FUZZY, WHITE BABY VULTURES ***** LACEBUG What a frilly, strangely structured little creature! The head points toward the picture's top, right corner, but of what use could those white, waffle-like "ears" be flaring from the head's sides? Why don't the transparent wings fold neatly beneath harder parts as in many insects, instead of sticking out like airplane wings? Volunteer identifier Bea in Canada is pretty sure that this is a Lacebug in the genus CORYTHUCHA, but it's not any of the common North American species. The wing venation is very close to that of Corythucha floridana, but that species lacks the black bars ours bears across its wings. Lacebugs are members of the True Bug insect order, the Hemiptera, which have sucking mouthparts, undergo simple metamorphosis, and possess forewings with thickened bases. Up North, Sycamore Lacebugs sometimes seriously damage Sycamore trees, and so their life cycles have been studied. In that species, one to several pairs of lacebugs may colonize a new leaf. The females may lay at least 284 eggs. Immature nymphs herd together at first but may move to new leaves upon reaching their fourth molt, or instar. Its life cycle is completed in only 43 to 45 days, and in the southern US several generations can occur per year. As lacebugs feed on leaf undersides first they cause a white stippling and later the leaf turns yellowish or bronzed. Severe infestations may cause the tree to shed its leaves in late summer. Several years of infestation can stress a tree, even kill it, but usually the damage is more esthetic than dangerous, and it's not worth trying to control the insects. ***** SCHOTT'S CEIBA HEAVY WITH FRUITS Last Sunday in an abandoned lot in Pisté a cluster of Schott's Ceibas turned up, enabling me to get a better idea of what the tree is like. Most surprising were the nearly spherical, muskmelon-size fruits shown at http://www.backyardnature.net/n/12/120318cb.jpg. I'd thought the fruits were slenderer. Once the fruits shed their cottony contents, their drying shells warp and wrinkle into odd shapes and remain on the tree awhile, giving the mostly leafless trees a bizarre and unkempt appearance. However, at the tips of certain branches new leaves -- digitately compound with seven or so leaflets -- are unfurling, their pale, springy greenness so promising and nice to see, as shown at http://www.backyardnature.net/n/12/120318cc.jpg. ***** MOUSE MELON The vine bears both male and female flowers. You can see a female one on the left, male on the right, at http://www.backyardnature.net/n/12/120318gd.jpg. The big difference between those two flowers is that the green calyx and yellow corolla of the female flower on the left arise from the end of an oblong ovary -- the future fruit -- while the male flower on the right arises directly from a slender pedicel. The female flower, then, is a good example of a flower with an "inferior ovary" -- an ovary with the calyx, corolla and stamens arising above it, instead of below it, as in more commonly encountered "superior ovaries." An immature fruit is sliced open at http://www.backyardnature.net/n/12/120318ge.jpg. That looks a lot like a ¾-inch long (20mm) cucumber for a good reason: The vine is a member of the Cucumber Family. It's MELOTHRIA PENDULA, which goes by such English names as Guadeloupe Cucumber, Creeping Cucumber, Squirting Cucumber, Melonette and, my favorite, Mouse Melon. It occurs throughout tropical and subtropical America, including the US Southeast. ***** SPANISH BAYONET FLOWERING Yuccas, genus Yucca, are one group of plants most of us can recognize instantly without resorting to field marks. Their large, white flower clusters erupt atop tufts of stiff, sharp-pointed leaves, which themselves often arise atop slender, branched stems. Most North Americans are familiar with Joshua Trees of the US Desert Southeast; Joshua Trees are quintessential yuccas rather similar to the one in our picture. A close-up showing our yucca's waxy, dangling, white flowers atop a branch's tuft of leaves is at http://www.backyardnature.net/n/12/120318yv.jpg. An old panicle bearing a single capsular fruit is seen at http://www.backyardnature.net/n/12/120318yw.jpg. This yucca goes by the English names of Spanish Bayonet and Dagger Plant. It's YUCCA ALOIFOLIA, native to the US coast from North Carolina to Louisiana, the Caribbean area and Mexico. It's "gone wild" in much of the US Southeast and elsewhere. Several cultivars have been developed, including 'Marginata' with yellow-margined leaves. There's a similar yucca, known as the Spanish Dagger, Yucca gloriosa, native to US coastal areas from North Carolina to Florida, also much planted and escaped, and likely to be confused with our Spanish Bayonet. However, that species, Spanish Dagger, is more branched, presents an overall moundlike appearance instead of our plant's tall-standing one, plus its leaves are bluish-green instead of our plant's dark green. ***** CROWN-OF-THORNS FLOWERING Note the thorny stem at the lower, right. The flowers don't look at all like normal blossoms, as shown at http://www.backyardnature.net/n/12/120318ev.jpg. Several times we've seen flowers with this same basic construction -- most recently those of the Poinsettia, Euphorbia pulcherrima. The basic construction of flowers in the genus Euphorbia consists of several tiny, unisexual male and/or female flowers arising inside a cuplike structure known as a cyathium. Several cyathia are then subtended by large, red bracts, or modified leaves, which in the Poinsettia most people imagine to be the flower's petals. You might enjoy reviewing Poinsettia flower anatomy at http://www.backyardnature.net/mexnat/poinsett.htm. Recognizing that here we have another Euphorbia, we can start understanding our thorny-stemmed plant's flower as seen in the last picture. In the center, the tiny, brown, oval things are the anthers of male stamens of several flowers. The five glistening, tongue-like items are glands on five mostly hidden cyathia. The red, veiny zone occupying most of the picture consists of two opposed bracts, which are modified leaves. That exactly the same basic structure as seen in Poinsettia, except that the parts are smaller and more crammed together. So, our thorny Pisté plant is the Crown-of-Thorns, EUPHORBIA MILII, much planted as an ornamental plant worldwide but native to Madagascar. The species name, milii, honors Baron Milius who introduced the plant into cultivation in France in 1821. ***** POMEGRANATES FLOWERING At the right in that picture you see the blossom's curiously large, unusually leathery, surprisingly reddish calyx subtending a somewhat larger wrinkled corolla. At the left the corolla has fallen off leaving the calyx's interior walls bristling with pollen-producing stamens. It's more normal for stamens to arise from below the ovary or from the walls of a corolla, not the walls of a calyx. Unusual floral anatomy is to be expected here, however, because these are flowers of the Pomegranate, PUNICA GRANATUM, and Pomegranate flower and fruit anatomy is so strange that normally the species is assigned to its own family, the Pomegranate Family, or Punicaceae. Once the flowers' ovaries have matured a little we start seeing our future Pomegranates, as shown at http://www.backyardnature.net/n/12/120318pm.jpg. The developing fruits in that picture, by the way, are good examples of maturing inferior ovaries. Inferior ovaries are those in which the stamens, calyx and corolla arise above the ovary instead of at its base. The ovaries in the picture are only about as thick as a finger. The mature pomegranates will be about the size of an orange. Pomegranates are native to southern Asia but grow wild in the Mediterranean, South America, and the southern US. Many cultivars exist, including double-flowered and dwarf ones. ***** DAHLIAS Both side and back views are shown. In the back view at the right, notice that the blossom's yellow ray flowers are subtended by a green involucre. If the terms "ray flower" and "involucre" confuse you, you may want to review our Composite Flower webpage at http://www.backyardnature.net/fl_comps.htm. To help distinguish dahlia flowers from similar common garden composite flowers such as chrysanthemums and zinnias, it's worth noticing that dahlia-flower involucres are composed of thicker but narrower outer bracts and thinner but broader inner bracts, as shown at http://www.backyardnature.net/n/12/120318dj.jpg. Also, dahlia leaves are opposite (two per stem node) and "odd pinnate." The leaves of our Pisté plant are three-pinnate, or trifoliate, as shown at http://www.backyardnature.net/n/12/120318di.jpg. In tropical America at least 36 wild dahlia species are recognized, and in the gardening world there are hundreds of cultivars, largely hybrids. There's much disagreement about how dahlias should be named. On the Internet some authorities use the name DAHLIA x GENERALIS to refer to garden varieties in general. You might enjoy the webpage "A Timeline of Important Dates in Dahlia Cultivation and Hybridizations" presented by the Stanford Dahlia Project. ***** EATING A STAR-APPLE In Pisté, Star-Apple fruits now are showing up for sale. You can see one I bought and sliced open at http://www.backyardnature.net/n/12/120318ch.jpg. At first I tried breaking the fruit apart with my thumbs but it was so full of white, sticky, milky latex that I made a mess. Then I used a knife. If I had cut the fruit across the middle we could have seen the "star" formed by the 3-8 seeds, but I made a longitudinal section showing entire black seeds clustering in the fruit's center. Star-Apples are sweet and juicy, and their juice is so sticky that afterwards your lips slightly stick together, and things stick to your fingers. The skin is just tough enough to make you wonder whether to eat it or not. If I hadn't worried about chemical residues on the skin, I'd have eaten it. ***** THREE THINGS GOING TO THE RIGHT For example, the other morning as I piddled about the hut I looked over and saw what's at http://www.backyardnature.net/n/12/120318x3.jpg. Succinctly and with flair and passion, something was being said in the language of unfurling Elephant Ear leaf-veins, in terms of shadows, curves and visual textures. If I let my mind go flat, it was just three things going to the right; but if I expansively space-timed myself, it was green life struggling outward, again and again penetrating lifeless shadow. Or, playfully, three yellow-green tones one after the other trailing off within a matrix of leaf-veinlet violin flutterings. And, of what good are such moments, and this kind of thinking? For one thing, they remind us how silly it is to question the value of something we could never define or explain, or even think about without prompting, but whose good message leaves us buzzing with delight and insight. ***** VENUS & JUPITER For the last month or so, back toward the west, each early evening the two brightest objects in the night sky, other than the Moon, have been drawing closer and closer, and now they're side-by-side, paired Evening Stars. But, they're too bright to be stars and they reside on the ecliptic -- the path followed by the Moon and Sun -- so obviously they're planets, not stars. They're so bright that I've been assuming they were Venus and Jupiter, and that's what my old Space Explorer computer program confirms, plus it says that Jupiter's "apparent magnitude" is -2.2, and Venus's is a dazzling -4.3. The smaller the magnitude number, the brighter the object. By comparison, the sky's brightest star, Sirius, is only -1.6. When Venus and Jupiter form in the night sky and the air turns cool and moist, a dizzying perfume from the flowers of an undetermined plant seeps into the air around the hut. I could track down the plant to see who it is, but somehow on these nights the plant's identity isn't important. What's important is to experience the moment exactly as it is, exactly right now. For the last month or so, when Venus and Jupiter appeared, that's when I've been walking my Estonian lady friend Malle home. With palm trees silhouetted against the starry sky above us, we feel the night's moist softness and smell the fragrance, but neither says anything about it, and I like that about her. Confronted with things as they are, what else, really, needs to be said? If you place the back of a flashlight to your forehead and beam the light into the woods, you see dozens of bright little glistens all around. They're reflections from wolf-spider eyes as the spiders roam the forest floor. You don't need a flashlight to see the bright yellow fire of fireflies and glowworms. Sometimes glowworms are hard to sneak up on, but other times you can get on your hands and knees and put your nose right up next to them and see them, their legs scrambling across curled-leaf surfaces, their oval bodies silhouetted inside their slow-moving little yellow orbs of self-made light. There are crickety sounds and maybe the Peacock screaming once or twice from a tree at the hotel next door, traffic noise from half a mile away, the crunches of our feet on the ground, the rustling sound of clothing rubbing skin, and the whisper of our own breathing. This story has no beginning or end, but just is. What else, really, needs to be said? ***** Best wishes to all Newsletter readers, Jim To subscribe OR unsubscribe to this Newsletter, go to www.backyardnature.net/news/natnat.php. Post your own backyard-nature observations and thoughts at http://groups.google.com/group/backyard-nature/ All previous Newsletters are archived at www.backyardnature.net/n/. Visit Jim's backyard nature site at www.backyardnature.net |