Overview
The Pima pineapple cactus (Coryphantha scheeri var. robustispina) was listed as endangered without designated critical habitat on September 23, 1993, under the Endangered Species Act of 1973, as amended. In the United States, the taxon occurs on land within the Altar and Santa Cruz Valleys in Pima and Santa Cruz counties of southeastern Arizona. Approximately 16 percent of the plants are known to be found on lands owned or managed by the federal government, with roughly 50 percent known on state government lands, another 5 percent known to be on tribal government lands and, lastly, 29 percent are known to be on lands owned by private entities. The taxon also occurs in northern Sonora, Mexico. We consider all Pima pineapple cactus individuals as components of a single population and we are currently aware of fewer than 8,000 extant plants across the range of the taxon. In addition, 1,837 are known to no longer exist, primarily due to development and mining. Population trends are considered declining, as monitoring within plots in the Altar Valley and on the Coronado National Forest. This, as well as repeat measures within two Pima pineapple cactus conservation banks, all show severe declines in the number of individuals recorded over the past few decades. Threats from urbanization, non-native plant invasion and alteration of fire regimes, drought and climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.
Learn more about climate change , border issues, mining, predation and others continue.
Scientific Name
Identification Numbers
Characteristics
Physical Characteristics
The Pima pineapple cactus inhabits Lower Sonoran desert-scrubland, desert-grassland, and the transition area between the two. It has been documented between 728 and 1,280 meters in elevation. The taxon is generally found on deep, silty and gravely, alluvial soils and have been located on early (Holocene) and late (Pleistocene) Quaternary, as well as Cenozoic period soils, individuals appear to be more abundant on the younger (Quaternary) alluvia and less abundant on older alluvia. It is suggested that both Holocene and Pleistocene surfaces are needed for the persistence of Pima pineapple cacti, with the younger, more nutrient-rich Holocene soils where Pima pineapple cacti grow more quickly, but can perish in more frequent fire, and the older and nutrient-poor Pleistocene soils acting as refugia where vegetation and fire are sparse. Most Pima pineapple cacti occur in the open and are exposed to full sunlight.
The Pima pineapple cactus is a small, perennial plant in the cactus family Cactaceae. The species is a succulent with singular or clumped stems that reach 5 to 46 centimeters in height and 5 to 21 centimeters in diameter. The surface of the stems is covered in 2 to 3 centimeters long rounded projections called tubercles, each of which is grooved along the upper surface and contains one to several place that secretes nectar to attract pollinators along the groove. At the tip of each tubercle, arising from small bumps covered in wooly hair, are groupings of seven to 20 straw-colored spines that darken with age, including a long smooth central spine. The yellow flowers open in July following summer rains, with green fruits developing in August.
Life Cycle
Although individuals can have a longevity of 30 or more years, in some areas, they have a much shorter lifespan, possibly due to competition with invasive non-native grasses.
- Pima pineapple cactus flower buds begin to appear in mid-May and the timing is related to photoperiod and rainfall.
- Flowering usually occurs in early to mid-July or five to seven days after the first summer rains of at least 3 mm and continues through the monsoon season.
- Individual Pima pineapple cactus flowers persist for a single day.
- There are few cactus species which bloom at this same time as Pima pineapple cactus.
- Pima pineapple cacti may not flower until they are more than 12 years of age and possibly not until between 20 and 25 years of age.
- Pima pineapple cactus fruits may contain up to 120 seeds, with an average of 91 seeds per fruit.
- Pima pineapple cactus fruit and seed are likely dispersed through gravity, ants, small mammals, and birds.
- Adequate winter precipitation is required for seed germination and seedling growth.
- Seedling cacti, in general, have very small roots, and, therefore, limited ability to access deeper water sources.
- The seedling stage of small cacti is the most vulnerable life stage due to the likelihood of desiccation.
- Cacti, in general, are very slow growing.
Pima pineapple cactus seed availability must coincide with wet years for germination and initial seedling survival.
Habitat
The Pima pineapple cactus inhabits lower Sonoran desert-scrubland, desert-grassland, and the transition area between the two. It has been documented between 728 and 1,280 meters in elevation. The taxon is generally found on deep, silty and gravely, alluvial soils and have been located on early (Holocene) and late (Pleistocene) Quaternary, as well as Cenozoic period soils. Individuals appear to be more abundant on the younger (Quaternary) alluvia and less abundant on older alluvia. It is suggested that both Holocene and Pleistocene surfaces are needed for the persistence of Pima pineapple cacti. The younger, more nutrient-rich Holocene soils where Pima pineapple cacti grow more quickly, but can perish in more frequent fire and the older, nutrient-poor Pleistocene soils acting as refugia, where vegetation and fire are sparse. Most Pima pineapple cacti occur in the open and are exposed to full sunlight.
Ecosystem with large, flat areas of grasses.
Area of land that receives no more than 25 centimeters (10 inches) of precipitation a year.
Geography
- The Pima pineapple cactus is known from Pima and Santa Cruz Counties of southeastern Arizona and northern Sonora, Mexico.
Timeline
Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.
6 Items