Myriophyllum verticillatum
 
Bracted Water-Milfoil

Whorl of Female Flowers, Bottom

Ruby Lake, Near Hudson Bay
18-July-2019

The flowers are in axils of whorled bracts.  The bracts are deeply pectinate and longer than the flowers.

Verticillatum: This species can be distinguished from other Saskatchewan Myriophyllum species as follows:

leaves mostly 8-45 mm long;  NOT [leaves 3-12 (22) mm long]

flowers in an emersed terminal spike; NOT [flowers in axils of submersed or emersed leaves]

distal-most flowers in axils of whorled bracts; NOT [distal-most flowers in axils of alternate bracts]

flower bracts usually more than twice as long as pistillate flowers; NOT [flower bracts usually less than twice as long as pistillate flowers]

stamens 8; NOT [stamens 4]

 

Myriophyllum: This family can be distinguished from other Dicotyledoneae aquatic plants as follows: 

plants growing as long strands; NOT [small tufted plants]

leaves whorled; NOT [leaves opposite]

leaves finely dissected; NOT [leaves entire]

leaves pinnately branched; NOT [leaves dichotomously branched]

flowers on spikes (except for Myriophyllum pinnatum); NOT [flowers in leaf axils]

stamens 4 or 8; NOT [stamens 12-16]