Asteraceae (Compositae)

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Asteraceae is the largest family of dicot plants and the second largest family of flowering plants coming next to Orchidaceae family (Monocot)
Various sources describe the total number of plant species as 23000 into 1620 genera and 12 subfamilies.
I was searching for a simple key to differentiate the plants from Asteraceae family (Also called as Compositeae)

… has divided the family into 3 main groups according to flower structures. I couldn’t find this in Flora of Maharashtra where the Key directly starts from Achenes and then the flower heads. Of course it takes into account the pattern of flower as we go further into the keys.

I found some interesting Links which describe the family in good manner.
Wikipedia link
Link

Some botanical terms need to be refreshed during examining the Asteraceae plants which are also described in these links.
Also adding a link of my old blog which has some basic information

In the daisy family, the flower heads are made up of many small flowers called florets, and are either homogamous or heterogamous. Heterogamous heads are made up of two types of florets, ray florets near the edge and disk florets in the center. Homogamous heads are made up of just one type of floret, either all ray florets or all disk florets.

Pappus a very commonly encountered term in describing Asteraceae.
The tuft of hairs on each seed of thistles and similar plants that assists dispersal by the wind.
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. (Wikipedia)
pappus – usually considered to be the remnant of the calyx on top of the achene/cypsela, and can be present either as capillary setae, coarse bristles, awns, paleaceous or simply present as an erose or laciniate crown. (http://www.kew.org)pappus

in daisy florets, a tuft or ring of hairs or scales borne above the ovary and outside the corolla (representing the missing calyx); a tuft of hairs on a fruit.
 
Here is the List of Plants uploaded so far by our members in this ongoing Asteraceae Fortnight. Around 175 plus plants has been uploaded so far.
Asteraceae–Shared by Members-May13.xls

 
 
 
We have covered 2 groups of flowers from Asteraceae family in May and Jun2013. This July fortnight we will be covering plants with inflorescence which has only Ligulate flowers in heads. I am copying some part of the glossary from KEW which clearly describes the meaning of Ligulate which will help in identifying which plants to post during the fortnight.

ligulate – in Compositae it refers to either a floret type or capitulum type where the corollas are modified into a flat, strap-shaped limb with 5 apical teeth, often with a short or absent corolla tube at the base. Such florets may be hermaphrodite or female. Typically in the tribe Lactuceae all florets are identical and ligulate, just different in size and maturity across the capitulum, also present in Catamixis (tribe Mutisieae).          ligule – in Compositae it is used with reference to the flat, strap-shaped limb, with 5 apical teeth, of the corolla in a ligulate capitulum, e.g. members of the tribe Lactuceae.
limb – the extended portion of a corolla such as that found in a ray florets, but also applied to the portion of the corolla above an often obvious corolla tube.

 
Well, no picture here, only key, in “Bengal Plants”.
I need this to resolve my post.
achenes beaked and also contracted at the base…. fusiform or oblong —– Crepis
achenes beaked and also contracted at the base…. compressed or flattened —— Lactuca
achenes not beaked; narrowed at base, truncate at apex; oblong with 4-5 rugose ribs —— Picridium
achenes not beaked; narrowed at base, truncate at apex; compressed, many ribbed —— Sonchus
achenes truncate at base as well as apex ——- Launaea

A few links (based on “Bengal Plants”) –
Pappus hairs feathery = Picris = Plant illustration
Crepis acaulis Hook.f. = Plant illustration and eflora link
Lactuca sativa L. = a cabbage like herb = Plant illustration
L. polycephala Benth. = eflora link (fig2) and eflora link
Picridium tingitanum Desf. = Plant illustration
Sonchus = efi site link
Lauanea aspleniifolia Hook. f. = efi thread ???
Lauanea nudicaulis Less. = Prenanthes procumbens Roxb. = efi thread
Lauanea pinnatifida Cass. = eflora link and Plant illustration
Thanks for the efforts …

We have received very few pictures of Achenes. Why can’t we have some good pictures of achenes showing at least some characters clearly? I request all members to post some close-ups of achenes…..

The key on achenes must have modified lately. e.g. Crepis acaulis is now Launaea acaulis. Latest (?) key can be found in FoC

 
Thanks, to …, species & genera pages of ‎‎‎Asteraceae (Compositae) in efloraofindia are now with images.
This work was jointly done by me, him & …
It is one of the biggest families in efi & the work started on 14.4.16 in a systematic way & was completed today only on 24.6.16. 
It involves inserting images on around 450 species pages (say around 2000 images) & 194 genera pages. It also involved a lot of cleansing work, correctly identify some of the threads, putting them at their proper places, proper formatting of the species pages etc. 
I request our members to pl. take up one family each & try to make efloraofindia more constructive. We will be rendering what ever assistance is required by the members, in this matter.

A experiment with Asteraceae : 1 post by 1 author.

Pl. check ‎Asteraceae (Compositae)‎
Here I have further classified it into subfamilies & tribes (for big subfamilies like ‎‎Asteroideae).
In this way we can have comparative images on either subfamilies (except for ‎Asteroideae) or tribes (for Asteroideae subfamily);
This should better help us in finding a suitable match for posted plants with some little expertise or experience.
I think we can follow this for some of the big families, if required. in future.
Any views in the matter will be highly appreciated.

Now you can feel the difference with comparative images available either at subfamilies or tribes level.
Pl. check

Carduoideae


Nice to know that Asteraceae has been divided into subfamilies or tribes for the convenience of users of efi.

Thanks, … Asteraceae family is very very big with numerous genera and species therein.
I personally find it easier to suggest to members to go through a reasonable number of comparative images at tribes or sub tribes.
It helps them to find the Id themselves. I also help them in a similar way. I find it quite easy (this way) to find the species for a layman.