Echinocereus coccineus -'red claret cup' - is a common plant of US southwest. It is one of the larger Echinocerei, often forming clumps of up to 3ft/1m across, with hundreds of stems packed together. Most of the forms are tertaploid, and also doious, e.i. bi-sexual plants. The pictured is a male flower, and it's stylus even if looks fine is dysfunctional, but pollen is produced and abundant. Female plans have no noticeable amount of pollen produced. Sometimes male flowers do make fruit with small number of seeds in them, showing that sexual divide is not always reliable in that species
This species was described by George Engelmann and is known for over 150 years. The specific name means 'red' and refers to the flower color.
In New Mexico and Texas there are areas where Echinocereus coccineus forms hybrids with Echinocereus dasyacanthus. Those plants have great flower color variation from pure white to orange, lavender, pink, salmon and anything in between.
This particular form comes from Zion NP area in southern Utah. This are generally spiny plants with darker straight centrals.
These plants are fairly easy in culture. They need lots of sunlight. To see flowers you need to start watering in late winter - early spring.