Cephalotus

HISTORY

Cephalotus follicularis, commonly known as the Australian Pitcher Plant, was first collected by Archibald Menzies, a naturalist with the Vancouver expedition of 1791. In 1792 La Billardiere, a naturalist with a French expedition, encountered the same plant on the Island of Esperance Bay and mainland Australia whereupon he described the plant and named it Cephalotus follicularis. Cephalotus is derived from the Greek word "kephalotus" meaning headed, referring to the open anthers of the stamen. The term "follicularis," referring to a small bag or pod, relates to the modified leaf structure.

NATURAL HABITAT

In nature Cephalotus grows exclusively along the southwestern coastal areas of Australia in swampy or boggy areas. The acid soil is peaty, having a high organic matter content. During the rainy season the plants may be partially submerged for short periods of time.

DESCRIPTION OF PLANT

Cephalotus follicularis is a herbaceous perennial with a rosette of leaves arising from a stout and sometimes surmounting rhizome. In older, mature plants secondary rhizomes emerge from the primary rhizome to form secondary plants. In summer (December through February in Australia) white pubescent flowers, which can number up to 100, are borne on flower stalks that often exceed 2 ft. (61 cm) in length. (Fig. 3-22) In the Northern Hemisphere plants flower during July and August.

Leaves

Cephalotus is evergreen and tolerates light frosts with no apparent ill effects. With the arrival of spring and warmer temperatures, longer days and more intense sunlight, new growth is initiated and a rosette of green, flat, oval-shaped leaves which are foliage or vegetative leaves develop. Toward the end of the active growing season (September to October) pitchered leaves are prodijced on the ends of long, pubescent petioles that extend beyond the rosette of foliage leaves so that the pitchers form a ring around the foliage leaves. Often leaves of intermediate form develop. They tend to be flat with a depression of varying depth at the tip. In some cases these intermediate leaves will form a pitcher which, instead of the usual oval-shaped hood, has a deeply incised hood, resulting in a hood with two pointed projections. In shade the plants, pitchers and foliage leaves tend to be large and green, whereas in full sunlight colors ranging from brilliant reds to purples decorate both types of leaves. Pitchers can reach 3 in. (8 cm) in length with a diameter of 1.2 in. (3 cm).

The pitchers are jug-shaped with a hairy lid over the orifice of the pitcher. (Photo 3-11) The lid presents a corrugated appearance resulting from the red to purple colored ridges which radiate from the attachment outward in a fan shape. The grooves are translucent. When light shines through them they appear as openings to insects inside the pitchers.

The openings of the pitchers are oriented outward from the center of the plant. It was once erroneously thought that the lid was capable of motion and could close over the mouth of the pitcher to incarcerate prey.

The pitcher is supported in the back by its petiole while its base usually rests on the soil. The hollow pitcher is given rigidity by 3 pubescent ribs on its front surface. The central rib extends the length of the front of the pitcher while the other 2 start at the mouth and extend to either pitcher side.

The mouth of the pitcher has a prominent rim which is reinforced by numerous ridges that terminate inside the pitcher as sharp, pointed spines. Below the interior rim of the pitcher is a collar about half the length of the lid, containing numerous nectar secreting glands, that overhang the cavity of the pitcher. The collar is differentiated from the cavity of the pitcher both in color and texture. The collar is pale, almost white, with a velvety texture while the cavity of the pitcher in mature specimens is streaked with dark red blotches and is shiny-wet looking.

The sides of the pitcher's cavity are glossy with digestive glands in the upper region. The digestive glands are concentrated in 2 symmetrical regions between the central rib and the rib to either side of it just above the bottom front of the pitcher. Internally these 2 regions are darker in color, usually deep maroon in mature pitchers. Externally they are lighter colored than the surrounding areas of the bottom region of the pitcher.

Flowers

The flower clusters are borne on a tall scape that may reach 26 in. (66 cm) in length. (Photo 3-12) Individual flowers are small, usually less than 0.2 in. (0.5 cm) in diameter and lack petals. (Fig. 3-23) The 6 greenish white sepals are attractive and appear very waxy. There are 6 long and 6 short stamens; all 12 are shorter than the sepals. Seeds are borne, usually singly, within each of the 6 free carpels. (Photo 3-13) The entire panicle is rather inconspicuous.

Fig. 3-22 Cephalotus plant with flowers.

Fig. 3-23 Cephalotus flowers are small and lack petals. The sepals are waxy. Of the 12 stamens, 6 are long and 6 are short.

Fig. 3-24 Longitudinal section of Cephalotus pitcher. Once inside the pitcher insects find that the smooth walls offer no foothold and the spines, which line the opening, present a formidable barrier.

Fig. 3-23 Cephalotus flowers are small and lack petals. The sepals are waxy. Of the 12 stamens, 6 are long and 6 are short.

PISTIL

SEPAL STAMEN

PISTIL

TRAPPING

The frontal ridges have been likened to ramps leading insects to the trap. Insects are attracted to the nectar in the collar region. Once inside the pitcher, it is difficult for the insect to escape. The collar is surmounted by the spines of the rim of the mouth which present a formidable barrier. If the insect slips, it winds up in the watery bath within the cavity of the pitcher. The walls in and above the water are smooth and offer no foothold. Should the victim manage to scale the walls after extricating himself from the digestive bath, he encounters the rim of the collar which is similar to a lobster trap in that it allows entrance but prohibits exits. The rim of the collar overhangs the walls of the pitcher virtually preventing an insect from climbing out. (Fig. 3-24) Flying insects may try to fly out through the transparent areas in the lid only to fall in the pitcher's enzyme and bacterial bath. Some believe that the transparent areas in the lid allow light to pass through and shine on the liquid below attracting insects to the pitcher's depths. Both theories are supportable.

SPECIES OF THE GENUS CEPHALOTUS

Cephalotus is a monotypic genus. The only species is C. follicularis Labill. CULTURAL REQUIREMENTS Planting Media

Sphagnum moss (living or non-living), sphagnum peat moss, mixtures of sand with sphagnum peat moss. Living sphagnum moss tends to overgrow Cephalotus plants when they are young; therefore, the moss needs regular pruning. But it does provide a beautiful green background for the reddish maroon pitchers and leaves.

Temperatures

Range from 38-95°F (3-35°C). Plants can survive a light frost. Cephalotus will grow well at constant temperatures of 70-85°F (21-29°C) the year around. We keep our plants at 38-40°F (3-4°C) during the winter while summer temperatures reach 95°F (35°C) or more. In their native habitat, temperatures are lower in winter than in summer. Our plants are thriving and produce flowers each year.

Dormancy

There seems to be no dormancy requirement. Water & Humidity

Keep soil damp or wet during the growing season or summer and if, during the winter, the plants are maintained at low temperatures such as in the 40-60°F (4-16°C) range, keep the soil drier.

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