Asimina tetramera, commonly known as the four-petal pawpaw, is a rare species of small tree or perennial shrub endemic to Martin and Palm Beach Counties in the state of Florida.

[4] By protecting existing populations, performing controlled burns, and planting new A. tetramera within its native range, conservationists hope to prevent this rare shrub from going extinct.

[5] Herbivory damages the developing shoots, which stimulates growth in the plant and extends the breeding cycle for the insects.

[5] The shelf fungus Phylloporia frutica attacks A. tetramera at wounded sites near the ground and the mushroom structure emerges from branching points on the plant.

[4] Common fruit-eating animals include gopher tortoises, raccoons, beach mice and other rodents, and other small mammals.

[5] The 3 inner petals of the flower form a chamber that beetles occupy between the female and male phases of floral development.

[13][5] Beetles feed on grooved structures covering the stamen, inner petal tissue, and pollen grains as they are released after maturation.

[4] Other associated plant taxa include scrub oaks (Quercus myrtifolia, Q. geminata, Q. chapmanii), saw palmetto, rusty lyonia, and other species of shrub.

[14] A. tetramera occurs only along the Atlantic Coastal Ridge complex in the excessively-drained quartz sand of the paola classification.

[4] The sand pine scrub ecosystem is mediated by frequent fires that historically created disturbance every 10–50 years.

[12] These disturbances enhance the structure and complexity of the system for several years by creating gaps in the canopy for colonization of different vegetation types.

[4] A. tetramera is easily outcompeted by larger sand pine and oak trees and even saw palmetto shrubs which are less likely to be shaded out.

[4] The presence of these frequent fires indicates better quality habitat for A. tetramera even if individuals have remained in a vegetative state for many years.

[4] As a result, the range of the shrub is limited to Martin and Palm Beach Counties in the state of Florida.

Rather than a continuous distribution across the counties, four-petal pawpaw populations exist in small patches within the identified range.

Fish and Wildlife Service's (USFWS) Five-Year review from 2022, the southernmost population of A. tetramera has disappeared.

[16] Pawpaw Preserve, Palm Beach County's smallest natural area, was established largely due to the presence of several examples of A.

Because the four-petal pawpaw is an endemic species (meaning it only occurs in a singular, small area), any amount of habitat loss has a great negative impact on its population status.

When human policies quench wildfires, the natural processes needed for four-petal pawpaws to survive and reproduce are lost.

The four-petal pawpaw is protected at the state level via the Florida Department of Agriculture and Consumer Services (FDACS).

It mentions that the Secretary of the Smithsonian Institution was ordered through the ESA to make reports on plant species that may be threatened or endangered.

[2] Reasons given for why the four-petal pawpaw should be listed as endangered include: Sections B and C (overutilization and disease/predation) were not considered as threats to A.

[12] A chart is provided in the 2022 five-year review which outlines all the sites where four-petal pawpaw populations have been identified.

Included in climate-change-related potential threats are sea level rise, increased average temperature, changes in precipitation patterns, and more frequent or intense hurricanes.

[12]  Sea level rise is identified as having a high potential for negative impact on A. tetramera because it could cause direct loss of the plants coastal habitat.

[12] Recommendations by the 2022 five-year review for continued management of the four-petal pawpaw include introducing more individuals in protected areas with appropriate habitat conditions.

[12] Recovery Activities include collecting A. tetramera seeds for "ex situ" safeguarding, continuing propagation, identifying suitable habitat for introduction, prescribed burns, and careful invasive species management.

[4]  Prescribed burns and biomass reduction (cutting back plants) are currently a management technique used in Jonathan Dickinson State Park.

The delisting criteria includes: This amendment also mentions that the population declines of A. tetramera may have caused a loss in genetic diversity.

This raises another point of concern because genetic diversity loss makes it easier for populations to be wiped out by major events (i.e. hurricanes, disease outbreak).