Duidaea

• Authority

  Carlquist, Sherwin. 1957. Anatomy of Guayana Mutisieae. Mem. New York Bot. Gard. 9 (3): 441-476.

• Family

  Asteraceae

• Scientific Name

  Duidaea

• Discussion

  The distinctive genus Duidaea has pollen grains, in D. pinifolia, similar to those of Gongylolepis. Grains of D. pinifolia (fig. 100 A-C) are sphaeroidal and spinose, and have thick walls. Rods of the inner ektexine (fig. 100 C) are relatively small. No features other than those found in Gongylolepis, however, characterize D. pinifolia. The exine structure of D. tatei (fig. 101 A-C), therefore, is surprising. Large lobe-like thickenings are found in intercolpar and polar areas. These are distributed symmetrically, two on each intercolpar face and one on each pole. In terms of the layers of the ektexine, this thickening is chiefly reflected by a widening of the outer ektexine (fig. 101 C), although the inner ektexine is also thicker in these areas. In addition to these prominent emergences, numerous minute spines are present on the unthickened areas of the exine. Pollen of D. tatei is further distinguished from that of D. pinifolia in that the shape of the grains is basically subprolate.