In this article we will discuss about:- 1. Characters of Lentibulariaceae 2. Distribution of Lentibulariaceae 3. Economic Importance 4. Affinities.
Characters of Lentibulariaceae:
Plants insectivorous, annual or perennial herbs, aquatic or terrestrial; flowers zygomorphic, hypogynous hermaphrodite, calyx persistent; corolla bitabiate or personate, stamens 2; carpels 2, syncarpous, superior, free central placentation.
A. Vegetative characters:
Habit:
Insectivorous, annual or perennial aquatic or terrestrial herbs.
Root:
Aquatic plants without roots; terrestrial with tap and branched roots.
Stem:
Erect, branched and week or rhizome.
Leaf:
Alternate or in basal rosettes, in aquatic genera leaves are mostly dimorphic, submerged leaves finally divided and bearing insectivorous bladders of complex structures, aerial leaves composing a floating rosette or reduced to scale like enations absent; in some terrestrial genera (Genlisea) dimorphism is represented by rosettes of leaves and tubular or pitcher-like insectivorous leaves appressed into the ground.
Insect catching apparatus:
In Utricularia the insect catching apparatus or traps are so-called bladders which are borne on much dissected submerged leaves, the bladders are thus metamorphosed ultimate leaf segments meant for catching aquatic small insect preys.
The mouth of each bladder is fitted with a valve which opens inwards but closing outwards as a result of response to the stimulus carried by sensory hair located at the entrance of the mouth of the bladder.
After closing up of the bladder by valve the insect caught inside cannot come out, they die, their decayed bodies are absorbed by special glandular hairs lining inside the wall of bladder.
B. Floral characters:
Inflorescence:
Scapose raceme or solitary.
Flower:
Bracteate, bracteolate, hermaprhordite, hypogynous, zygomorphic.
Calyx:
Sepals 5, united in open bilabiate or five lobed, usually persistent, valvate or sometimes imbricate, gamopetalous.
Corolla:
Petals 5, gamopetalous, united in bilabiate or personate, lower lip spurred or succate at the base and with distinct palate (i.e., typical personate corolla, the lower lip with projecting lobes) near the throat, imbricate.
Androecium:
Stamens 2, attached by the filaments, to the base of corolla; anthers monothelous the anther lobe sometimes medianly constricted, dehiscing longitudinally.
Gynoecium:
Carpels 2, Syncarpous, superior, unilocular ovary with free central placentation; style very short or stigma sessile, bilobed, ovules many, anatropous, often sunk in the placental tissue.
Fruit:
Capsule many seeded, opening by 2-4 valves.
Seed:
Small, non-endospermic.
Pollination:
Entomophilous-special adaptation for insect’s visit.
Floral formula:
Distribution of Lentibulariaceae:
Lentibulariaceae or Bladderwort family comprises of 5 genera and 250 species (Utricularia is largest, about 200 species) comprising insectivorous plants of aquatic and marshland flora is distributed in the temperate and tropical regions of Old and New world.
Economic Importance of Lentibulariaceae:
The members of the family are of little economic importance.
Ornamentals:
A few species of butterwort (Pinguicula) are offered in the domestic trade as ornamentals and species of Utricularia are grown in aquaria.
Affinities of Lentibulariaceae:
The family superficially resembles some of the Scrophulaiaceae but is distinguished by 2 stamens and free central placentation. The presence of the tiny bladders in aquatic species or other forms of insect trap, is also distinctive.
Common plants of the family:
1. Biovularia – floating aquatic plant.
2. Pinguicula – butterwort.
3. Utricularia – from Latin utriculus, a small bladder, referring to the bladder-like organs borne on the leaves of most species.