Agarwood is not produced by a single tree species. It is produced by a group of related trees spread across two genera, Aquilaria and Gyrinops, both of which share the same basic resin-forming biology covered in our guide to how agarwood resin forms. Almost every regional name used in the trade today, Vietnamese, Cambodian, Indonesian, Assamese, and the rest, ultimately refers to a particular species within one of these two genera, growing in a particular place.
This guide is the foundation for the regional profiles that follow it. It sets out what reliably distinguishes Aquilaria from Gyrinops, where each genus is actually found, and where the science gets less tidy than trade marketing sometimes suggests.
Aquilaria and Gyrinops: The Two Genera Behind Agarwood
Aquilaria and Gyrinops are the two plant genera responsible for essentially all of the agarwood reaching the global market today. According to Kew's Plants of the World Online, the most widely cited reference for current plant taxonomy, Aquilaria currently comprises around 21 recognised species and Gyrinops around 9, though species counts in actively studied tropical genera like these can shift as new research is published, and not every count agrees exactly across sources.
Aquilaria is by far the more commercially dominant of the two. Species such as Aquilaria malaccensis, Aquilaria crassna, Aquilaria sinensis, and Aquilaria filaria collectively account for the large majority of agarwood in international trade. Gyrinops is smaller in both species count and historical trade volume, but it is far from a footnote: Gyrinops species are the primary source of agarwood from large parts of eastern Indonesia and are an increasingly significant part of the Papua New Guinea trade, covered in their own regional guides later in this hub.
Where They Sit in the Plant Kingdom
Both genera belong to the family Thymelaeaceae, within the order Malvales. Aquilaria was first formally described by the French botanist Jean-Baptiste Lamarck in 1788. Gyrinops was described a few years later, in 1791, by the German-born botanist Joseph Gaertner. Both genera have therefore been recognised as botanically distinct for well over two centuries, even though, as later sections of this guide explain, the genetic line between them has turned out to be less clean than that long history of separate classification implies.
How Botanists Tell Them Apart
In the field, botanists distinguish Aquilaria from Gyrinops mainly through floral structure, particularly stamen number and arrangement, and through differences in fruit characteristics such as capsule shape and colour. These are the kinds of features used in formal botanical keys and herbarium identification, not features a buyer could ever check on a piece of finished agarwood.
This is worth being direct about: there is no reliable way to look at a chip of resin-infused wood, or smell it, and determine with confidence whether it came from an Aquilaria or a Gyrinops tree. Genus and species identification happens at the point of harvest, based on the living tree, long before the wood is processed into the chips, powder, or oil that eventually reach a buyer. Once agarwood enters trade, species claims rest on documentation and seller knowledge of regional sourcing, not on anything verifiable by inspection alone.
Where Each Genus Grows
Aquilaria has the wider range of the two genera by a considerable margin. Collectively, Aquilaria species are native across mainland and island Southeast Asia, northeastern India, Bangladesh, southern China, the Philippines, Borneo, and parts of New Guinea, though no single species covers that entire range. Specific species tend to map onto specific countries: Aquilaria crassna is the dominant species across Vietnam, Laos, Cambodia, and Thailand; Aquilaria malaccensis is the species most associated with Peninsular Malaysia, Assam in northeastern India, and large parts of Indonesia; Aquilaria sinensis is concentrated in southern China; and Aquilaria filaria is found in eastern Indonesia and parts of Papua New Guinea.
Gyrinops has a much more concentrated distribution, centred on eastern Indonesia. Gyrinops versteegii, often referred to locally by names such as "ketimunan," is the most commercially significant Gyrinops species and the main source of the agarwood associated with eastern Indonesian islands such as Flores and Sumbawa. Outside Indonesia, Gyrinops walla, known locally as "wallapatta," is native to Sri Lanka, and Gyrinops ledermannii has recently been identified as a significant source of agarwood in Papua New Guinea, a development covered in detail in our Papua New Guinea guide.
Want to see how this plays out for one of the most heavily traded origins?
Vietnamese Agarwood: Trầm Hương and Kỳ NamWhy the Distinction Matters When You're Buying
Regional marketing names in the agarwood trade are, in practice, shorthand for a particular species growing in a particular place. "Cambodian oud" almost always implies Aquilaria crassna. "Papua agarwood" increasingly refers to Gyrinops ledermannii rather than the Aquilaria species once assumed to be the source there. Knowing which genus and species sits behind a regional name gives a buyer a more concrete reference point than the name alone, and it is the framework the rest of this hub's regional guides are built around. A side-by-side view of how these origins compare is covered in our regional agarwood comparison guide.
Scent and quality comparisons between Aquilaria and Gyrinops, or between species within the same genus, are widely discussed in trade and collector circles, but much of that discussion is qualitative and trade-derived rather than settled by controlled scientific comparison. The same caution that applies to wild-versus-plantation scent claims, covered in our guide to wild vs plantation agarwood, applies here: treat strong claims about one genus or species being categorically superior as trade opinion rather than settled fact, however often they're repeated.
A Blurrier Line Than It Looks: What DNA Studies Show
Although Aquilaria and Gyrinops have been treated as separate genera since the eighteenth century, modern molecular research has complicated that picture. Studies analysing plastid genome data have found Gyrinops to be paraphyletic with respect to Aquilaria, meaning that, genetically, some Gyrinops species appear to sit within the same evolutionary lineage as Aquilaria rather than forming a cleanly separate branch. In plainer terms, the morphological features botanists have long used to separate the two genera do not necessarily line up with how closely related the species actually are at the DNA level.
This is an active area of botanical research rather than a settled reclassification, and it has not changed how the genera are named and used in trade or in this guide. It is worth knowing about mainly because it explains why occasional disagreements over a species' genus placement turn up in scientific literature, even though Aquilaria and Gyrinops remain the standard working categories for everyone from botanists to traders.
Both Genera, Same Legal Protection
Whatever the finer points of their evolutionary relationship, Aquilaria and Gyrinops are treated identically under international trade law today. Aquilaria malaccensis was the first agarwood-producing species listed under CITES Appendix II, in 1995. Every remaining Aquilaria species, along with the entire Gyrinops genus, was added to the same protection in 2004. Since then, no agarwood-producing species in either genus can be legally traded internationally outside the CITES permit system, a framework covered in full in our guide to agarwood and CITES.