Passionflowers

 

Flower of Passiflora incarnata, the Purple Passionflower.
Rowan County, North Carolina. 

Passionflower flowers are as beautiful as they are complex.  They are classified in the genus Passiflora, a group of plants found mainly in the neotropics which is home for more than 500 species of passionflowers.  Two passionflowers are found in the Southeastern United States, Purple Passionflower, Passiflora incarnata and Yellow Passionflower, Passiflora lutea. 

The flowers have five sepals and five petals that are similar in shape and color.  Above the sepals and petals is a ring of long filaments called the corona. Arching from the center of the flower over the corona are five, pollen producing, stamens.  Then above the stamens are the carpels with three stigmas, the female flower parts that receive pollen. 

This striking flower structure caught the attention of early Spanish missionaries in the New World.  To these holy men, the flower was telling the story of the passion of Jesus. The five sepals and petals represented the ten faithful disciples.  Judas was left out for betraying Jesus and St. Peter; the founder of the Catholic Church, was not represented by a sepal or a petal because he denied Jesus on the night of his arrest.  The corona of filaments stood for the crown of thorns, the five stamens for Jesus's wounds on the cross and the three stigmas represented the three nails used in the crucifixion.  This religious interpretation of floral structure is how the plants got their name. 

Flower bud of Purple Passionflower.
Rowan County, North Carolina.

Purple Passionflower bud opening.
Rowan County, North Carolina. 

Purple Passionflower bud as it opens showing sepals,
petals and filaments of the corona. 
Rowan County, North Carolina. 

        

Fully open Purple Passionflower.
Rowan County, North Carolina.

Passiflora incarnata, the Purple Passionflower, is an herbaceous vine with three-lobed leaves.  The plant can ramble across the ground and produce tendrils that allow it to grow over other plants.  As its name suggests, the flower has purple sepals and petals.  The filaments are banded with purple and white while the stamens and carpels are yellow-green.  Passionflowers are pollinated by bees and develop large, green edible fruits.   

Three-lobed leaf of Purple Passionflower.
Rowan County, North Carolina. 

A Carpenter Bee (Xylocopa sp.) pollinating Purple Passionflower. 
The bee is collecting nectar as a stamen of the flower
 is depositing pollen on its back. 
Rowan County, North Carolina.

Two Purple Passionflower fruits. 
Rowan County, North Carolina. 

Yellow Passionflower (Passiflora lutea) is the second species in our area. Like Purple Passionflower, Yellow Passionflower is also a vine and its leaves have three lobes.  Yellow Passionflower is not as showy as the Purple Passionflower and has small yellow flowers.  But these flowers have the same complex structures as Purple Passionflower.  

Yellow Passionflower (Passiflora lutea) with its
rounded, three-lobed leaves and small yellow flower.
Rowan County, North Carolina. 

Yellow Passionflower has the same flower structure as its
more colorful relative, the Purple Passionflower.
Rowan County, North Carolina. 

Passionflower is the host of Gulf Fritillary butterflies (Agraulis vanillae).  These beautiful butterflies lay their eggs on the leaves of Passionflowers.  The eggs hatch and the larvae eat the leaves and transform into a chrysalis that hangs on the stems.  After a few weeks the adult butterfly emerges and feeds on the nectar of many plant species.  The bright orange color of the Gulf Fritillary is advertising its unpalatability.  Predators avoid this butterfly because it contains noxious chemicals that the larvae collected while eating Passionflower leaves.  Even the caterpillars of Gulf Fritillary advertise their toxicity with their bright orange color and black spikes. 

Gulf Fritillary (Agraulis vanillae) caterpillar on Purple Passionflower.
Rowan County, North Carolina. 

Passionflowers thrive in the hottest summer months. Even in the midst of a drought they bring on the those great flowers. So while many plants are riding out the heat, passionflowers put on their show.

Adult Gulf Fritillary.
Rowan County, North Carolina. 

A Count of Butterflies

 

A Gulf Fritillary (Agraulis vanillae) perched on Verbena brasiliensis.
Mecklenburg County, North Carolina. 

A day in high summer was set aside to count butterflies.  This count took place north of Charlotte, North Carolina, in forests and fields, near ponds and in powerline rights-of-way.   Thirteen people in six groups spent one day identifying and counting every butterfly they saw.  The count was conducted under the auspices of the North American Butterfly Association, a group whose mission is butterfly conservation. 

Junonia coenia, the Common Buckeye.
Mecklenburg County, North Carolina. 

Our little group consisted of Ron Clark, a master birder and butterfly whiz, Diane and me.  We did not start at sunrise like on a bird count, but at the civilized hour of 10 am.  Butterflies are exothermic and need the sun to raise their body temperature before they can fly.  Our day began in a meadow at Rural Hill, an historic farm in north Mecklenburg County.  We immediately began to see lots of Common Buckeyes (Junonia coenia).  These medium sized butterflies are marked with marvelous eyespots on the wings.  A single Monarch (Danaus plexippus) flew past seeking milkweeds.  

Monarch (Danaus plexippus).
Mecklenburg County, North Carolina.

Our second stop was Holly Bend, with its 18^th century house and grounds.  There we began to see forest and edge haunting butterflies including Eastern Tiger Swallowtails (Papilio glaucus), Hackberry Emperors (Asterocampa celtis) and Carolina Satyrs (Hermeuptychia sosybius).  

Hackberry Emperor (Astreocampa celtis).  This butterfly was
drinking sap on the truck of an oak (Quercus sp.)
Mecklenburg County, North Carolina. 

Carolina Satyr (Hermeuptychia sosybius).
Mecklenburg County, North Carolina. 

We found a couple of exquisite, tiny butterflies here; the Gray Hairstreak (Strymon melinus) and Eastern Tailed Blue (Cupido comyntas).  Both these butterflies have tails at the rear edge of the wings that look like antennae.  They also have eye spots on their hindwings.  The fake eyes and antennae makes it appear the head of the butterfly is at the back. This deception extends to the tails moving like antennae when the butterfly moves its wings.  The tails and eye spots trick predators into attacking the back edge of the wing while the butterfly escapes.  

Strymon melinus, Gray Hairstreak showing its antenna-like hairs and eyespots.
Mecklenburg County, North Carolina. 

Eastern Tailed Blue (Cupido comyntas) another butterfly with tails and eyespots. 
Mecklenburg County, North Carolina. 

After lunch at Lancaster’s Bar-B-Que we tackled Cowan’s Ford Wildlife Refuge.  This 650-acre sanctuary is located in a bend of the Catawba River and has a variety of habitats.  As we walked through a forested area, we found the uncommon Gemmed Satyr (Cyllopsis gemma).

Gemmed Satyr (Cyllopsis gemma).
Mecklenburg County, North Carolina. 

One of the most productive areas at Cowan’s Ford was in the powerline right-of-way.  Butterfly Weed (Asclepias tuberosa), sporting its orange flowers, was common here and were magnets for the butterflies.  It was here we started to see large numbers of Silver-spotted Skippers (Epargyreus clarus).  Skippers are an odd group of butterflies that are often hard to identify.  The Silver-spotted is the largest of the skippers and has easy to see white spots on the underside of the wings.  

Silver-spotted Skipper (Epargyreus clarus)
feeding on Verbena. 
Mecklenburg County, North Carolina. 

Gulf Fritillaries (Agraulis vanillae), one our most beautiful butterflies, were also in the powerline right-of-way.  From above Gulf Fritillaries are bright orange marked with black and white.  This contrasts with the underside of the wings that have multiple, brilliant silver spots.   

Gulf Fritillary.
Mecklenburg County, North Carolina. 

Another good butterfly under the powerline was the Pipevine Swallowtail (Battus philenor).  This large black butterfly has a patch of iridescent blue on the hind wings that flashes as it hovers.  Pipevine Swallowtails lay their eggs on Pipevines (Aristolochia sp.).  These plants contain toxic compounds that the caterpillars store and make the adult butterfly unpalatable to predators. This toxicity is the basis for a group of other butterfly species that mimic the Pipevine Swallowtail.  The mimics includes Black Swallowtail (Papilio polyxenes), the black form of the female Eastern Tiger Swallowtail, Spicebush Swallowtail (Papilio troilus) and Red-spotted Purple (Limenitis arthemis).  On the count day we saw all the species in this mimicry complex except the Black Swallowtail. 

Battus philenor, the Pipevine Swallowtail.  This toxic
butterfly is the model for a number of mimic species.
Mecklenburg County, North Carolina. 

Red-spotted Purple (Limenitis arthemis)
a mimic of the Pipevine Swallowtail. 
Mecklenburg County, North Carolina. 

We saw many colorful Sleepy Orange (Eurema nicippe) butterflies.  They are bright orange above and yellow below.  Its odd name comes from a mark on the forewing that looks like a closed eye.  

Sleepy Orange (Eurema nicippe).
Mecklenburg County, North Carolina. 

Another colorful little butterfly we saw was the Pearl Crescent (Phyciodes tharos).  It has a complex color pattern of orange and black.  This butterfly's name comes from the pearly crescent band along the rear edge of the wing.    

Pearl Crescent (Phyciodes tharos).
Mecklenburg County, North Carolina.

A patch of Verbena brasiliensis at the Cowan’s Ford parking lot delivered up large numbers of skippers including Delaware Skippers (Anatrytone logan) and Zabulon Skippers (Poanes zabulon).  

Delaware Skipper (Anatrytone logan).
Mecklenburg County, North Carolina. 

Zabulon Skipper (Poanes zabulon).
Mecklenburg County, North Carolina. 

We also spotted an American Lady (Vanessa virginiensis) in the Verbena stand. These colorful butterflies have a cob-web pattern on the underside of the wings and two large eye spots.  A related butterfly, the Painted Lady (Vanessa cardui) is also found in this area too but it has small eye spots on the wings. The saying goes, American Ladies have big eyes.   

American Lady (Vanessa virginiensis) with its big eyes.
Mecklenburg County, North Carolina. 

We had a great time spending a day with the butterflies but there was a more serious purpose to this endeavor.  Butterflies and other insects are sensitive indicators of environmental quality and change.  If butterfly numbers or species are in decline something is wrong in the environment.  Habitat loss, herbicide and insecticide use and climate change are all contributing to crashes in butterfly populations.  This year the migratory population of the iconic Monarch butterfly was placed on the endangered list.  The count in Mecklenburg County, North Carolina showed a slight decline in number of species reported over the last decade.  These results say trouble in on the way, or is already here.