Tag Archives: Hawks Bluff

Flip-Flopper Flowers

07 Mar

Spurred Butterfly Pea

Centrosema  virginianum

Fabaceae

John and George devoted much of the day to revising our Grass and Sedge web site www.floridagrasses.org (you will still see the “bad” old version), but today was too enticing to remain cooped up inside, so we took a botanical look at the Hawk’s Bluff Trail, a scrubby coastal dune area near Jensen Beach, and part of Savannas Preserve State Park.  Any witness would testify that the flower show today was Butterfly Pea, Centrosema virginianum.  Hundreds in bloom decorated the trail.

These are curious members of the Pea Family, with an odd twist.  To establish comparative context, let’s start with normal pea-type flowers.  There are  five petals (see the diagram, top yellow images).

• A “banner,”  which is a showy billboard rising up above the rest of the flower
• Two “wings” which stick out straight from the center of the flower.   These paired petals can be small or sometimes tough to see.  They are not important today.
• And a “keel” at the base of the flower made of two petals joined to form a boat-shaped envelope, open-side-up serving as landing platform for bees.  The keel contains the business parts of the flower, the pollen-receptive stigma and the pollen-making anthers.   When a bee lights on the keel, the keel bends down, and the stigma and anthers pop up to contact the underside of the visitor.   This sort of normal pea flower is detailed in an earlier blog
  

Now, turn the beat around.  In Centrosema (and in similar Clitoria) the flower is essentially the same but flipped, with the keel on top and the banner at the base, the banner now serving as landing platform. When an insect visits these flowers, the keel with its stigma and anthers is above the bee.

Top: Standard pea-type flower
Bottom: Flipped Centrosema flower

Side view, with X-ray vision, of Centrosema keel and the style hidden within

A similar flip-flop is seen in Orchids.  In a minority of Orchids the big showy petal (called the labellum) rises up just like the banner in normal Pea Flowers.  And the stigma/anther unit (called the column) serves as landing platform just as the keel hiding the stigma and anthers does in a standard Pea Flower.  (Such Orchids are called non-resupinate Orchids.)

The majority of Orchids, however, are flipped 180 to resemble Centrosema, that is, with the labellum (banner) as the welcome mat, and the stigma-anther unit arching above.   (Such Orchids are called resupinate Orchids.)  Here are some resupinate Orchids.   CLICK

You can see the odd resemblance of resupinate Orchids to Butterfly Peas.  And so can so-called “Orchid Bees,” that is, Euglossine Bees, caught in the act occasionally of visiting Centrosema.  BUZZ here  Is the Centrosema floral-flip a mechanism to poach Orchid bees^*?

Those flowers are flip-floppers!

————————————————————————————————

Notes:

^*Don’t let me over-state the “Orchid Bee” -Centrosema hunch, which has occurred to other botanists before today.  Euglossine bees are not limited to Orchids (and to Orchid lookalikes), and Centrosemas do have a variety of floral visitors.  But still, Orchido-centric bees visiting Orchid-mimicking flowers is fertile hunch fodder.

John and I enjoyed the common Centrosema virginianum,  but there are additional Butterfly Peas in Florida. Centrosema arenicola is state-listed as endangered; most of its range is Central Florida.  Another, presumed to be a garden escape, is Centrosema sagittatum.  (There are similar species of Clitoria also.)

Being good legumes, Centrosemas serve as cover crops,  green manures, and rubber, and as livestock fodder.

John's and my blog this week

• X
• Facebook
• Email
• Print
• PDF

Like Loading...

 

3 Comments

Posted by George Rogers on March 7, 2014 in Butterfly Pea

 

Tags: centrosema, Hawks Bluff

Passion on the Bluff

17 Dec

Passiflora edulis, P. incarnata, P. foetida, P. suberosa

Passifloraceae

Yesterday John and George walked the Hawk’s Bluff Trail near Jensen Beach, Florida.  The Bluff is a coastal dune of white sugar sand overlooking a vast and lovely marshy area, essentially Savannas Preserve State Park.

As we set off downslope we noticed a fruit resembling a giant yellowish egg dangling from a distant tree. As we approached we found the hillside to be smothered Kudzu-style with a massive non-native edible passionfruit vine (Passiflora edulis) smothering all in its path.   So we took some photos of this overbearing plant and feasted on passionfruit like a couple castaways.

Passiflora edulis (by JB)

We all love passionfruits, but did you know some species have poisonous contents, even cyanide?  Bioactivity might explain the prevalence of passionfruit extracts in traditional medicines in various cultures.

Yellow Passionfruit (by JB)

There are about 11 species growing outside of cultivation in Florida, some native, some not.

Now let’s get one thing straight, the passion in passionflower has nothing to do with lust.  We’re talking about the Passion of Christ.  According to legend, the Conquistadors interpreted the flower somewhat self-servingly as divine sanction of their conquest.  I’m not going to repeat the interpretation of the blossom with respect to the Crucifixion here, as that account is all over the Internet.

But John and I didn’t contemplate religion or cyanide—we just enjoyed a little passionfruit and mosied along the trail.  We did, in fact, discuss religion very soon thereafter,  however, when we came upon this preview of Hell at the bottom of the hill. (For a more graphic preview you might enjoy Scaremare at Liberty University in Lynchburg, Virginia.  CLICK LIKE HELL)

Twisted souls in Hades. (Well, okay, really Saw Palmetto stems after a fire at Hawk’s Bluff.)

Now before we go any further, let’s lighten up and get friendly with the basic construction of a passionflower.   They are unique, they are complex, and they are diverse.  We’ll use John’s side view of the non-native Passiflora foetida to explore the structure.  The white (purple-tipped) fingers above the sepals and petals are called the corona (crown); these are appendages on the petals and sepals apparently responsible for advertising,  and may help control access to the flower.  The pedestal in the floral center is called the androgynophore;  it  elevates the stamens and stigmas.  Look closely:  the five stamens in this species spread from the top of the pedestal, and the three stigmas are just above the stamens.

Passiflora foetida (by JB). Note the pedestal, with 5 stamens near the top and three stigmas.

To make it all more interesting, the parts move (not necessarily the same ways in every species).  The best-known movement is that the stigmas start out well above the anthers, so that the visiting insect pushing under the anthers is merely dusted with pollen.  Later, the stigmas descend to the level of the anthers or below and brush pollen off the visiting insect.  In John’s photo above, the stigmas have dropped to nearly the anther level.      More intriguingly, there are reports—in just one species known to me—of the entire pedestal tipping toward a visiting bird.

And who does visit?  The diversity of pollinators matching the diversity of Passionflowers is dizzying:  bees (mostly), wasps, hummingbirds, moths and butterflies, bats, and probably more.

Corky Stem PV (by JB)

We started our hike with the big imposing Edible Passionfruit, and ended it with the  modest native Corkystem Passionflower, favored among native plant gardeners as larval host for Zebra Heliconian, Gulf Fritillary, and Julia butterflies.  Maybe that tough corky stem limits the larval devastation, which can be considerable.   But what pollinates Corkystem Passionflower?  This is one of the few species known to be compatible with its own pollen, which may help explain how it became an invasive exotic pest on the other side of the world.   At least in some places wasps are the reported main pollinators.  Butterflies visit the flowers too, and bees no doubt  buzz in, although I can’t claim to have witnessed it.

Native Passiflora incarnata (by JB)

John's and my blog this week

• X
• Facebook
• Email
• Print
• PDF

Like Loading...

 

8 Comments

Posted by George Rogers on December 17, 2012 in Passion Flower

 

Tags: Hawks Bluff, Passiflora, Passionflower, Passionvine

• Authors

  • John Bradford
  • George Rogers
  • George Rogers
  • Dee Staley

• Browse by Subject

  Browse by Subject Select Category Acorns Agalinis Agave Air-Potato Allapattah Flats Alligator Flag Alligator Weed Ant Lion Aquatic emergents Arrow Arum Asiatic Snakewood Asteraceae Autograph Tree Axil-Flower bacopa Bald Cypress Bald Cypress Twig Midge Gall Baldwin’s Eryngo Baldwin’s Milkwort Baldwin’s Spikesedge Balsam-Pear Baybean Beach Peanut Beautyberry Bedstraw Black Mangrove Black Senna Blackberries Bladderpod Bladderwort Blazing Star Bloodberry Blue Maidencane Blue-Eyed Grass Bluestem Grass Bluethreads Bog White Violet Bogbutton Border Rush Bracken Brookweed Bur Marigold Burnweed Butterfly Pea Butterwort Buttonbush Buttonweed Cabbage Palm Caesar Weed Canada Toadflax Canadian Horseweed Canna Capparis Carolina Redroot Carolina Willow Carolina Willows Carpetweed Castorbean Casuarina Cat-tails Catbriars Catesby’s Lily Ceratopteris Chamaecyse Chapman’s Oak Cheesytoes Chia Christmas Lichen Cinchweed Cinnamon Fern Climbing Aster Club-Moss Clustered Bushmint Coco Plum Coinvine 1 Compound Leaves Coreopsis Cowbane Crematogaster Cup Grass Cuphea Cyanobacteria Cyanobacteria revisited Cyanobacterial Mats Dahoon holly Dahoon Holly fruits young Dayflower Daytime leaf movements Desodium Devil’s Claw Devil’s Potato Dodder Dog Fennel Dollarweed Domatia Dragonflies Drosera Drymary Dull Leaf Coffee Dwarf Huckleberry Eelgrass Elephant Grass Eriocaulon Fakahatchee Grass False Foxglove False-Croton False-Pennyroyal Feathershank Feay’s Palafox Fern Allies Fetterbush Fiddle-Leaf Dock Fire Ants Firebush Floating Ferns Florida Scrub-Jay Florida-Rosemary Forestiera Fragrant Kyllinga Frostweed Gallberry Galls Ganoderma lucidum Gasteromycetes Glade Lobelia Godenrod Golden Club Golden-Asters Goldenrod Gopher Apple Grass Grass Pink Orchid Grassleaf Spurge Gratiola Graytwig Green Cay Groundel-Trees Gumbo Limbo Hammock Snakeroot Hatpin Helmet Skullcap Hempvine Herbicides Hickory Hog Plum Hottentot Fern Huckleberry Hydrcotyle Hypericum fasciculatum Inkberry Innocence Iris Jack in the Bush Jack in the Pulpit Japanese Millet Johns’-Wort Jointvetches Jointweed Juncus megacephalus Kiss Me Quick Knotted Spikerush Kosteletzkya Lancewood Lark Daisy Lawn Orchid Leafless Swallowwort Leptospron Leptothrix Liatris Lichen Line Lichens as parasites Linden Leaf Hibiscus Live Oak Lizard’s Tail Lobelia paludosa Loblolly Bay Love Vine Lubber Grasshopper Ludwigia Manatee Mudflower Manyspike Flatsedge Marsh Elders Marsh Gentian Meadow Succession Meadowbeauty Melaleuca Mexican Poppy Mexican-Clover Mistletoe Mitreola petiolata Monkey-Oranges Monotropa Morinda royoc Morning Glory Moss Mulberry Weed Muscadine Grape Mushroom Mushrooms Myrsine Myrtle Oak Narrowleaf Yellowtops Nettles Nickerbean Nitella Northern Needleaf Nostoc commune Nyctinasty Octoberflower Osprey Guano Pale Smartweed Pallavicinia Partridge Pea Passiflora foetida Passion Flower PawPaw Pepper-Grass Periphyton Persimmon Phragmites Phyla Pickerel Weed Pineland Chaffheads Pipestem Pitch-Apple Pitted Stripeseed Plume Grass Pokeweed Polypremum Pond Apple Prickly Pear Primrose-Leaf Violet Primrose-Willow Psilotum Puffballs Puncture Vine Purple bladderwort Ragweed Rattlesnake Master Red Mangrove leaf pressure Red Mangroves Red Spiderling Red-Bay Rhizomes Rose-Apple Rose-Gentian Rose-Rush Rosettes Royal Palm Rubbervine Sabatia decandra Sacoila Salt and plants Saltbush Saltbushes Samolus Sand Mat Sand Pine Sandyfield Beaksedge Santa Maria Feverfew Saw Grass Saw Palmetto Sawgrass Revisited Scarlet Sage Scleria Scrub-jay Sea Blite Sea Oxeye Sea Rocket Sensitive Brier Septicweed Shade leaves Shoestring Fern Showy Rattlebox Sisyrinchium angustifolium Skyblue Lupine Slash Pine Slash Pine branch loss Smartweed Soil bacteria Southern Needleleaf Southern Needleleaf revisited Spanish Moss Spatterdock Spider-Lilies Spigelia Spotted Beebalm St. Andrew’s Cross St. Johns Wort Staggerbush Stenandrium Strangler Fig Strap Fern String Lily Succulents Sugarberry Sumpweed Sundew Sunflower Sunny Bells Superweeds Swamp Dogwood Swamp Fern Sweetbay Magnolia Switch Grass Tall Pinebarren Milkwort Tarflower Tassel Flowers Tendrils Thistle Toothache Grass Toothpetal False Rein Orchid Torpedo Grass Toxic Algae Tracy’s Beaksedge Trentepohlia Tribulus Tropical Soda Apple Tropical Umbrella Sedge Two Leaf Nightshade Uncategorized Utricularia cornuta Vallisneria Vanilla Variegation Varnishleaf Violet Virginia Buttonwood Virginia Swamp Mallow Vittaria and Octoblepharum Wakodahatchee Wetlands Walter’s Ground Cherry Water-Lettuce Wax Myrtle West Indian Wood Nettle Wetland Species Whisk Fern White Mangrove White Mangroves White Peacocks White Pine Barren Aster White Star Sedge White Stopper White Water Lily Wide Leaf Painted Sedge Wild Coffee Wild Coffee Stem Tip Wild Lime Wild Rice Willow secretions Wind Pollination Winged Sumac Wireweed Xyris moth Yellow Butterwort Zebra longwing Zebra Longwings Zigzag Bladderwort

• Search

  Search

• Email Subscription

  Enter your email address to subscribe to this blog and receive notifications of new posts by email.

  Email Address:

  Sign me up!

  Join 460 other subscribers

• Nature Blogs

  

• Networked Blogs

  NetworkedBlogs

  Blog:

  Treasure Coast Natives

  Topics:

  Florida plants, Florida habitat

  Follow my blog