top of page
Key to Arisaema of North America

Arisaema :  key to North American Taxa


1a. Leaflets (3-5). Spadix blunt apically, shorter than

       spathe.                                                                    2. A. triphyllum


2b.  leaflets 5.                                                                 var. quinatum


2b.  leaflets 3.                                                                 3.


3a.  Leaves glaucous beneath at maturity. Spathe flange

       4.5 - 9.0 mm wide.  Spathe hood green or green with

       purple stripes. Sterile spadix appendage club-shaped,

      rarely cylindrical. Stomatal guard cell length mostly

      greater than 40 µm                                                   ssp. triphyllum


3b.  Leaves polished or lustrous beneath, not glaucous.

        Spathe flange 1-3 mm wide. Sterile spadix

         appendage cylindrical, rarely club-shaped. Stomatal

         guard cell length mostly less than 40 µm.           4.


4a.  Spathe tube strongly fluted. Spathe hood green

       with white or purple stripes.                                ssp. stewardsonii


4b.  Spathe tube not fluted or rarely weakly fluted.

        Spathe hood green or purple, not striped.   ssp. pusillum


1b.  Leaflets (5-) 7-13 (-21). Spadix tapering apically,

        much longer than spathe.                                  4. A. dracontium


5a.  Spathe tightly inrolled around the spadix. To 1.5cm

       broad when unfurled.                                             var. dracontium


5b. Spathe flared distally, forming a blade, to 2.5cm

       broad.                                                              var. macrospathum



Based upon:


Ward, Daniel B. (2012) Keys to the Flora of Florida – 31 Arisaema (Araceae).  Phytologia 94(2) pp. 151 – 158.

Key to Arisaema of North America

Out of Stock
bottom of page