Native Plants

Sintenis’ Quina

Antirhea sintenisii

USDA symbol: ANSI

perennial tree

Puerto Rico: native

Meet Sintenis’ quina (Antirhea sintenisii), one of Puerto Rico’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Caribbean and the urgent need for plant conservation. While you’re unlikely to find this tree at your local nursery, understanding its story can deepen your appreciation for ...

Sintenis’ Quina may be listed as rare in your area.
Global Conservation Status

Status: S1 | Critically imperiled: Typically 5 or fewer occurrences or under 1,000 remaining individuals.

Sintenis’ Quina: A Rare Caribbean Treasure Worth Protecting

Meet Sintenis’ quina (Antirhea sintenisii), one of Puerto Rico’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Caribbean and the urgent need for plant conservation. While you’re unlikely to find this tree at your local nursery, understanding its story can deepen your appreciation for rare native plants and inspire conservation-minded gardening choices.

What Makes Sintenis’ Quina Special?

Sintenis’ quina is a perennial tree that typically grows as a single-stemmed specimen reaching heights of 13-16 feet or more. As a member of the coffee family (Rubiaceae), it’s related to plants that have given us everything from morning coffee to beautiful ornamental gardenias. The tree was named after botanist Paul Sintenis, who collected extensively in Puerto Rico during the late 1800s.

You might also encounter this species listed under its scientific synonym, Stenostomum sintenisii, in older botanical references.

Where Does It Call Home?

This tree is exclusively native to Puerto Rico, where it has evolved to thrive in the island’s tropical conditions. Unfortunately, Sintenis’ quina is now found in only a handful of locations across the island, making every surviving specimen incredibly precious.

  • Species observed
  • No observations

A Conservation Alert: Critically Imperiled Status

Here’s where things get serious: Sintenis’ quina has a Global Conservation Status of S1, meaning it’s critically imperiled. With typically five or fewer known occurrences and very few remaining individuals (fewer than 1,000), this tree is teetering on the edge of extinction. This rarity status means that if you’re interested in growing this species, you should only obtain it through responsible sources that support conservation efforts.

Growing Conditions and Care

Given its Puerto Rican origins, Sintenis’ quina would likely thrive in USDA hardiness zones 10-11, requiring warm, frost-free conditions year-round. The tree would probably appreciate:

  • Tropical to subtropical climate conditions
  • Protection from freezing temperatures
  • Adequate moisture during establishment
  • Well-draining soil

However, specific cultivation requirements remain largely undocumented due to the species’ rarity and limited study.

Should You Grow Sintenis’ Quina?

The short answer is: probably not, unless you’re involved in legitimate conservation efforts. This tree’s critically imperiled status means it should be left to conservation professionals and specialized botanical gardens working to preserve the species.

Instead, consider supporting conservation by:

  • Growing other Puerto Rican native plants that are more readily available
  • Supporting organizations working to protect Caribbean plant diversity
  • Choosing native plants for your own region to support local ecosystems
  • Learning about and sharing awareness of endangered plant species

The Bigger Picture

While you might not be planting Sintenis’ quina in your backyard anytime soon, its story highlights the importance of protecting plant diversity. Every rare species like this one represents thousands of years of evolution and potentially valuable genetic resources for the future.

By choosing native plants for your own garden and supporting conservation efforts, you’re helping ensure that future generations might still marvel at rare treasures like Sintenis’ quina in their natural Caribbean habitat.

Sometimes the best way to love a plant is to admire it from afar while working to protect the wild spaces where it belongs.

Antirhea sintenisii is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Antirhea sintenisii is also known as:

Stenostomum sintenisii Britton & | USDA symbol: STSI7

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Classification

Group: Dicot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Subclass: Asteridae
Order: Rubiales
Family: Rubiaceae Juss. - Madder family
Genus: Antirhea Comm. ex Juss. - quina

Species: Antirhea sintenisii Urb. - Sintenis' quina

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA