Classification Of Carnivorous Plants

Of the one-quarter of a million species of flowering plants about 600 are carnivorous. They are divided into two groups based on corolla structure, Choripetalae and Sympetalae. The group of plants categorized as carnivorous belong to 7 families and 15 genera. Family names can be recognized by their suffix, which is 'aceae/ This classification is illustrated in Chart 1.

Chart 1

Choripetalae Group

Byblidaceae

Byblis Cephalotaceae Cephalotus Dioncophyllaceae Triphyophyllum Droseraceae Aldrovanda Dionaea Drosera Drosophyllum Nepenthaceae

Nepenthes Sarraceniaceae Darlingtonia Heliamphora Sarracenia

The plants in the Sympetalae group have flowers which are personate. Personate flowers have petals that are joined or fused together forming a two-lipped corolla terminating in a tube. They exhibit bilateral symmetry, having only one plane that can be drawn through the flower that will divide it into two parts that are mirror images of each other.

The plants in the Chloripetalae group have flowers in which the petals are not joined together and the flowers exhibit radial symmetry, meaning the flower parts are arranged around a circle and can be divided into mirror images by any plane that passes through the center of the circle.

Sympetalae Group

Lentibulariaceae

Genlisea Pinguicula Polypompholyx Utricular ia

Chart 2: List of genera, with their type of trapping mechanism and geographic range.

Number of

Genus

species

Geographic Distribution

Type of Trap

Aldrovanda

1

Europe, Asia, Africa, and Australia

Active

Byblis

2

Australia

Passive flypaper

Cephalotus

1

S.W. Australia

Passive pitfall

Darlingtonia

1

California & Oregon, U.S.A. Western Canada

Passive pitfall

Dionaea

1

North & South Carolina, U.S.A.

Active

Drosera

120

Omnipresent

Passive flypaper

Drosophyllum

1

Morocco, Portugal, and Spain

Passive flypaper

Genlisea

14

Tropical Africa & Tropical South America, Madagascar

Passive lobster

Number of

Genus

species

Geographic Distribution

Type of Trap

Heliamphora

6

Northern South America

Passive pitfall

Nepenthes

71

Area surrounding and including the East Indies

Passive pitfall

Pinguicula

50

Northern Hemisphere and South America

Passive flypaper

Polypompholyx

2

Australia

Active mousetrap, suction type

Sarracenia

9

North America

Passive pitfall

Triphyophyllum

1

West Africa

Passive flypaper

Utricularia

ca. 300

Omnipresent

Active mousetrap, suction type

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