Conyza species- Kamrup district, Assam

 
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/6._Conyza_sp._-_Head_IMG_1748.jpg?part=0.6&view=1&vt=ANaJVrGZIutSRGkRtbBbjhC6K-jIlgEjlUgfSuGW1c65Vzp3YrIcxFlJVfEVRscxi0CZ4TOVGIa-jGMdidEoJMC3oulmL3t0K1JKOB_8bXvidyee5pHzM_Q
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/7._Conyza_sp._-_Head_IMG_1775.jpg?part=0.7&view=1&vt=ANaJVrH4K8Che_Cp6I95DoazyZ86sjvbSl6ZYHw6uUhFfjSP4gXcosAuRzSSu0vWznIA8y7ySCyTuC9lMBa85tVJAdU1zsUkNZqVEywfUqj2n-j8dXpKzdw
 
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/8.Conyza_sp._-_Head_IMG_1779.jpg?part=0.8&view=1&vt=ANaJVrFnaSHiqEYKOQmN2cn4KGG_GtTYjuin9wg4y08SgR88EZxLNkb0Orr_6ywvKLQ8dlSBBV6saYVvhc36rPxbLesfNSkmSG6O8MAfhMXepKSpUcq_1VE
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/13._Conyza_sp.-_branched__IMG_2019.jpg?part=0.13&view=1&vt=ANaJVrH15issL7dvSZSd9lrNIInr_xb6ML8A3Ryi5tZjNeHMfynGyO6qB5RZK5Rnh4u4YiO64dFl96W9as-E2y8V_sn6fZ2fxPsI3n3i6_Oshessmg46dl8
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/12._Conyza_sp.__Basal_leaf_IMG_2016.jpg?part=0.12&view=1&vt=ANaJVrFlfltwW4zY9qE5YeieH_VvshQPdUa4L7cnizI8QiQE9Yf3TUcbNQKxI9Tip0BZmxpVmDngkOv00yJnPVDq3UwdTI7xUVpqDu4TWXJym5A3q8SUb6U
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/11._Conyza_sp.__IMG_2015.jpg?part=0.11&view=1&vt=ANaJVrEbz8BmTQkGwqh_38RUKQ7C5Ll1drIZraVkLLMN0BHev4xPIztOmmqK_sTfL4fZz-f5FoD2hAgsgh5khu7kei8tjbPjQOd4GKn1b8XW4dUSFFGa4lU
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/10.Conyza_sp._Basal_leaf_IMG_1948.jpg?part=0.10&view=1&vt=ANaJVrFoa7BJM0C-eKR_OhOw1i3JU9E3olCoU5zTcDhISlLdL4vc57nyX5mUbazJ4fWanIIc1eLskm_u9GHl8XYpisgyAW2ZoBhip8nc-WmwiLNQFo9ycoM
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/9._Conyza_sp._Ribbed_stem_IMG_1955.jpg?part=0.9&view=1&vt=ANaJVrENEVeczhxS7xMV2jq1klrEsnrB-KfAVQSOy_2Vmc_UKnMLAQLVNDcFTW8Q0-LIWmFVmHx518n46h2R6W8cP4Dk_9b3qp3TsXMxwXw1SPP3ONgnKF0
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/5._Conyza_sp._-_Head_IMG_1747.jpg?part=0.5&view=1&vt=ANaJVrGAp-ai9SAP8Ro6t0UOmBwdqOL0xTpaAV6iav_1daZO9OmIsfdKTDszQXPw23llhY1sdx3zPWZODo3PuVGAOOKfxJh38tKDuKwmdUibR6unNWUdsug
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/4.Conyza_sp.-_Leaf_IMG_1773.jpg?part=0.4&view=1&vt=ANaJVrHzGEEcYSIA35sblxEx9P7ob0Ik1K4rss7k5UHlZuKGhtCEZVV5x0JQ-SX88suPIwRqbu2L8_PSapy6U6IZSGYxvTwhrgeU-ajfeo9hJXLDHe2dUL8
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/3._Conyza_sp._IMG_1738.jpg?part=0.3&view=1&vt=ANaJVrHlxTjaNxM0yNo1z3Jw_NYF6OHyw8cx2ElRjlJd0xT_4XD7uOhEyxMgUTAiCjhtpH02OIn3VENqIuxweSk9uIIgGjduxvJCA2WV2xHgWP-5f8SCqiU
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/2.__Conyza_sp._IMG_1744.jpg?part=0.2&view=1&vt=ANaJVrGvP7nbw55rsHa-9HcUl7TmnsrfFOeArc69zXmhsqW2hBW-JckwntUZXrqwMCjQ7vIEZc6nchAEfl6XtKAbMP4vp2gA_2UzvJe74axlseCbif50eyU
https://08511630493324166816.googlegroups.com/attach/9261b4fe6ac9338f/1._Conyza_sp_-_Habit_IMG_1745.jpg?part=0.1&view=1&vt=ANaJVrGH_Rg3L9wfrNdGs70mvNX9TEUgNCkaqCkGienQ10iKa4LPhmVM1VlFx3HL7lnkwQtQeRvkc4zXEalJr883hEPoUeQX1IECYFJEVPVevArYMvpkrhA
 

I had attached images (1 to 8) in my earlier post where I thought them as Conyza bonariensis. Fortunetly I got hints from ... about C. sumatrensis. Then I searched other specimen grown in different places of the same region and collected them (Image No. 11 - 13). I then dissect the reproductive parts of the the specimen and got the following characters. So please ID the Conyza sp. whether it is C. bonariensis or sumatrensis. 

Date :10.04..2013 (Images no - 08) & 30.05.13 (Images no. 11-13)

Location: Kamrup district

Family : Asteraceae

Genus & species : C. bonariensis or sumatrensis. (?)

Habitat: Grows wild.

Habit : Herb, more than 5 feet (more than 150 cm Image No. 11)

Inflorescence : Radiate head .6cm (length) & 0.3-0.4 cm (w); bract two serriate, hairy, no long hair at the apex of the bract.

Flower : Disc floret few, . 6 cm.; pappus . 4 cm; corolla .5cm, 5 lobed, yellow

Ray florets(ligulate) many, .5 cm, ligule not distinct; corolla .4 cm.


I had seen all three growing in Kashmir and found some interesting facts.
Conyza bonariensis is the earliest to flower in May, continuing into june, has more spreading habit, longer and broader leaves and few larger and nearly ovoid to somewhat broader-based heads narrowing towards top, with no visible rays.
 
C. candensis flowers mostly in June, the plants are erect, delicate, linear with much smaller nearly cylindrical heads with distinct ray florets. the plants are barely taller than 1 m.
C. sumatrensis (syn: C. albida) is a much taller and robust plant often reaching 2 m ot more, much more robust, with heads almost as long as C. bonariensis, but more cyllindrical, without evident ray florets. The leaves are broader like C. bonariensis, but perhaps more broader if we take L vs B ratio into consideration. The plant becomes prominent August onwards and flowers in August to October in Kashmir and Chakrata where I saw it.

 
 
 
 
 
Comments