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Artificial second generation and backcross hybrids involving Echinocereus dasyacanthus (Texas rainbow cactus), E. coccineus (a species of claret-cup cactus), and E. X lloydii (Lloyd’s hedgehog cactus) were examined for morphological and reproductive characteristics. The hybrids grew from seed to flower in about four years, and they exhibited high fertility as measured by pollen stainability, crossability, and fruit-set. A rare breeding system in Cactaceae, dioecy, was further examined in E. coccineus, using field and controlled pollination tests. Functional dioecy was documented for E. coccineus in Trans-Pecos Texas. Al results suggested that E. X lloydii in eastern Pecos County, Texas, is a complex and dynamic population probably comprising first and later generation hybrids, including backcross hybrids. The experimental hybridizations also tended to support the occurrence of introgression into both putative parental species.