Tropical Lilythorn

Scientific name: Catesbaea melanocarpa

POWO Status: Shrub

IUCN Red List threat level: Not Evaluated

GPS Location: 17° 42′ 53.68″ N, 64° 49′ 48.34″ W

Medicinal Uses

Catesbaea melanocarpa, also known as Chokeberry or Black Chokeberry, has a long history of use in traditional medicine and is widely studied for its numerous potential health benefits. These effects are primarily attributed to its exceptionally high content of powerful antioxidants, specifically polyphenols like anthocyanins and proanthocyanidins.

The medicinal uses of Catesbaea melanocarpa include:

Cardiovascular Health: Extracts and juices have been shown to help manage risk factors for heart disease. Benefits include lowering blood pressure, total cholesterol, and LDL (“bad”) cholesterol, as well as improving overall lipid profiles in some patient groups. It exhibits anti-inflammatory, anti-atherosclerotic, and antiplatelet activities, which help protect blood vessels and the heart.
Diabetes and Metabolic Syndrome: It may have antidiabetic effects by helping to regulate blood sugar levels, improving insulin sensitivity, and protecting pancreatic beta cells from damage. The fruit can be a beneficial part of the diet for managing type 2 diabetes and metabolic disorders.
Antioxidant and Anti-inflammatory Effects: The high concentration of antioxidants helps to scavenge free radicals, which are unstable molecules that can damage cells and contribute to chronic inflammation and various diseases, including cancer and neurodegenerative conditions.
Gastrointestinal and Liver Health: Native Americans traditionally used the fruits to treat colds and stomach ailments. Modern research suggests the fruit can protect the gastric lining from damage and potentially improve liver function.
Immune System Support and Anti-Infective Properties: Extracts have demonstrated antibacterial activity against certain harmful bacteria (like E. coli) and antiviral effects against influenza viruses. Regular consumption of the juice has been linked to a reduced incidence of urinary tract infections in some studies.
Potential Anticancer Activity: Test-tube and animal studies indicate that the compounds in chokeberry may help inhibit the growth of certain cancer cells (e.g., colon, breast, leukemia) and can enhance the effects of some chemotherapy drugs.
Neuroprotective Effects: The fruit may offer protection against age-related cognitive decline and neurodegenerative diseases due to its antioxidant and anti-inflammatory properties, potentially improving memory and motor function.

While these findings are promising, many studies note that more comprehensive human clinical trials are needed to fully determine the safety, efficacy, and optimal doses for specific therapeutic uses. Chokeberry is typically consumed in processed forms like juices, jams, or supplements due to its naturally astringent taste when raw.

Observations:

Phenological Markers – Catesbaea melanocarpa

Common Name: Tropical Lilythorn
Scientific Name: Catesbaea melanocarpa Krug & Urb.
Family: Rubiaceae

Leaf Phenology

Leaf Type: Small, simple, opposite leaves; oval to elliptic; dark green and leathery with short petioles
Evergreen: Yes — retains leaves year-round under stable tropical conditions
Leaf Flush: New growth typically emerges after rainfall or following flowering; young leaves are lighter green
Senescence: Individual leaves may yellow and drop gradually; often subtle and continuous rather than seasonal

Flowering

Inflorescence: Solitary, tubular, white flowers with long corolla tubes, often axillary
Blooming Period: Likely seasonal and rainfall-dependent, often in late spring to early summer (based on habitat and related species)
Pollinators: Probably moths or butterflies, based on floral morphology (long tubular flowers adapted for long-tongued pollinators)
Phenological Indicator: Showy white flowers emerging singly from leaf axils; often appear with or shortly after new growth

Fruiting

Fruit Type: Rounded berry; initially green, turning dark purple to black when mature
Fruit Development: Follows flowering by several weeks to months; berries may persist on plant
Dispersal: Possibly birds or small mammals
Phenological Indicator: Visible dark berries among foliage or replacing flowers

Suggested Photo Angles

Whole plant form (small, spiny shrub with stiff branches)
Close-up of leaves and opposite arrangement
Axillary white flower with long corolla tube
Developing and mature dark-colored berries
Leaf flush and fruit/flower overlap

Notes for Monitoring

Phenology may be irregular or highly dependent on seasonal rainfall and microclimate conditions

Catesbaea melanocarpa is extremely rare and federally endangered, known from a few populations in the U.S. Virgin Islands and Puerto Rico

Natural populations are typically found in dry, coastal scrub or thorn woodland, often on limestone or rocky soils

Monitoring flowering and fruiting is critical for conservation and propagation efforts