Ranunculaceae

Ranunculaceae

The family includes about 50 genera and 1500 species distributed in temperate and colder regions of the world.

Ranunculaceae is a large family containing a number of well known wild flowering plant and garden ornamentals, such as buttercup (Anemone) poisonous plant and also medicinal plant such as Aconitum napellus.

Field identification:

Herbs, leaf with sheath base, lamina often dissected, flowers bisexual stomata and carpels number spirally arrange, ovary superior, fruit achene and folical.

Distribution:

The family is cosmopolitan distribution throughout the world but is concentrated in temperate and cold region, of northern and southern hemisphere.

Diagnostic character:

Mostly herbs, sometime shrubs rarely trees, or climber or woody climber e.g clematis gratus are woody climber. The perennial herb species usually persist by mean of condensed root stock or rhizome.

Ranunculus ficaria have rhizome.

Leaf:

Mostly alternate, opposite and climates in ranunculus species, pamptly lobed or compound leaf stipule absent.

Inflorescence:

Solitary flowers or cymose, raceme, pennicles.

Flowers:

Bisexual, actinomorphic with spirally arrange stamen and carpels. Hypogynous (ovary superior below)

Calyx:

5 sometime 3 or many and free, polypetalous.

Corolla;

Petals 5 rarely 4 or many and free often with nectaries. Some time perianth is not differentiate in to sepals or petals.

Androecium:

Many stamens free spirally arranged looking and facing outward. Dehiscence of stamen longitudinally.

Gynoecium:

Simple many carpels unilocular with single or many ovules and placentation marginal.

Ovary:

superior, style 1 stigma 1

Fruit:

Achene, berry, follicle or capsule.

Seed:

With small embryo endosperm present.

Variation in the family.

The family shown variation in flowers.

Zygomorphic [Aconitum]

Ranunculus [actinomorphic]      

              

The family shows a wide variation in flowers structure and also wild variation  in pollination method. The ranunculaceae are generally protandrous. The stamens shedding their pollen before the ovary mature. This reverse case a protogynous the ovaries maturing before the stamen, also occur in this family.

Variation in this process favour cross pollination and out breeding. Different seed dispersal is by variety of agencies, Clematis pulsetella, have style  which lengthen after pollination in to long feathery structure adopted for wind dispersal. some species of Ranunculaceae e.g R. arvensis have hooked spines on the surface of for animals dispersal.

Helleborus sp. have some oil containing swelling on the seed testa, which attracts ants which then disperse the seed.

Phylogenetic relationships:

The Ranunculaceae are how generally regarded as   primitive family view put forward by A. Lawren de Jussia as long as 1773. It is widely regarded as most probably having evolved from ancestral magnoliaceae stack.

The family is related to Berberideacae, Minispermaceae. The ranunculaceae and berberideacae are phytochemical related in the position in alkaloid berberin. The order in ranunculus closely related to the order nymphiales.

On one side and to the mangonliales  and liliaceae on the other side.

Some phylogenetic is see relationship with primitive order Alismatcles [water plant] it is because of convergent evolution [both survive in same habitat]. A closed relationship between some family of order ranunculus berberidaceae order papviraline its widely accepted.

Phylogenetic find out by:

1.     By morphology

2.     Hybridization