Creosote Bush Inch-Worm

Digrammia colorata
(Semiothisa colorata)

Creosote Bush Geometridae, Semiothisa, Digrammia  in Sonoran Desert photo © by Mike Plagens

With a long proboscis this moth is reaching nectar deep in the bloom of Larrea tridentata. Mohawk Mountains, Yuma Co., Arizona. 20 Feb. 2016. Wing span is about 20 mm.

Geometridae -- Inch-worm Moth Family

This pale, delicate moth is the adult stage of an inchworm larva (caterpillar) that feeds on fresh, new leaves of creosote bush. In the spring time, if there has been sufficient rain, the adult moths emerge from pupae that have been resting in the ground. They can also emerge at other times of the year when conditions are favorable. At the same time, this emergence very often coincides with the blooming of the creosote flowers. The freshly emerged moth is taking nectar from a flower and in the process getting some pollen rubbed onto its scales. When it leaves this plant there is a very high probability that it will visit another creosote bush in search of a place to lay eggs - because this is the preferred, if not sole food plant. This dual relationship provides food for moths and pollination services for the plant.

Creosote Bush

Creosote Bush

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Copyright Michael J. Plagens, page created 1 March 2016