Arch-nutted Comb Bur
Pectocarya recurvata
Scanned live specimen found at Phoenix, Arizona, Jan. 19, 2003.
Enlarged view of four nutlets forming a bur. This image is available at Wikimedia Commons.
This is one of the most abundant of the desert wildflowers in Arizona. It mostly goes unnoticed, however, because it is so small. The specimen illustrated at left has a single open bloom, 1 mm across, with 5 petals - barely visible at upper right. The curious fruits are four nutlets ... each segment is a single seed encased in a carpel that has a disected, barbed margin. A mature fruit can be seen near the main central stem of this specimen. There are several other very similar species of Pectocarya.
SPRING ANNUAL: Ephemeral spring annual appearing in the Sonoran Desert
late Dec. to early April depending on moisture.
FLOWERS: Minute, five-petaled, white flowers in small clusters.
FRUIT: Four curved nutlets with burr appendages.
LEAVES: Linear and grass-like.
STEMS: Entirely herbaceous and ephemeral usu. less than
10 cm tall.
RANGE: Common across the Sonoran Desert on rocky slopes and flats.