Decoding Angraecum Hybrid Notation: Understanding the ‘×’ Symbol and Parentage

What the “×” Sign Means in Orchid Hybrid Names

The multiplication sign (×) is the standard typographic cue that a plant name refers to a hybrid. It is used both in the formal scientific name of a hybrid (a nothotaxon) and in the informal “hybrid formula” that lists the two parents. The International Code of Nomenclature for algae, fungi and plants (ICN) and the International Code of Nomenclature for Cultivated Plants (ICNCP) both prescribe this convention.^[2][3]

Placement Before a Genus – Intergeneric (nothogenus)

When the × appears before a generic name, the name is a nothogenus – a hybrid genus created from two (or more) accepted genera. In Angraecum breeding this most often involves Jumellea. The nothogeneric name is formed by combining elements of the parent genera, and the × signals that the name is not a natural genus but a hybrid one.^[1][2]

Example:

• × Angellea Glic. – an artificial hybrid whose formula is Angraecum × Jumellea.^[1]

In the Kew Plants of the World Online entry the description explicitly states that the hybrid formula is Angraecum × Jumellea, confirming the use of the leading × for an intergeneric name.^[1]

Placement Between Two Genera – Hybrid Formula

When two generic names are linked by × (e.g., Angraecum × Jumellea), the expression is a **hybrid formula**. It tells the reader the exact parental genera but does not create a new nothogeneric name. This format is common in registration databases and in horticultural literature when a formal nothogeneric name has not yet been published.^[4][5]

Example from the Orchid Registry:

• Angraecum florulentum × Angraecum eburneum subsp. xerophilum – the parentage of the grex ‘Shooting Star’.^[5]

Notice that the × is placed between the two species epithets, indicating a direct cross between them.

Placement Before a Species Epithet – Interspecific (nothospecies)

If the × appears before the species epithet (e.g., Angraecum × corniforme), the name refers to a **named interspecific hybrid** (a nothospecies). This is the botanical way to publish a hybrid that is recognized as a distinct taxon, even though the individual plants may vary considerably.^[2][3]

In such cases the parentage is usually given in the protologue or in a hybrid formula elsewhere, but the formal name itself carries the × to signal its hybrid origin.

Direction of the Cross and the Role of ♀/♂

The × symbol itself does not indicate which parent supplied the ovule (seed parent) and which supplied the pollen. By convention, the **seed (female) parent is listed first**, but authors may also add the sex symbols ♀ (seed) and ♂ (pollen) for clarity. The New York Botanical Garden guide notes that “the direction of a cross may be indicated by including the sexual symbols … or by placing the female parent first.”^[4]

Example with symbols (from the Orchid Registry):

• ♀ Angraecum florulentum × ♂ Angraecum eburneum subsp. xerophilum

When symbols are omitted, the order of the names conveys the direction, but this is not enforced by the Codes; it is simply a widely‑adopted practice.

Practical Tips for Reading Labels, Registrations, and Grex Names

Growers frequently encounter hybrid notation on plant tags, in the RHS International Orchid Register, and in commercial catalogs. Here are the key points to decode them quickly:

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Additional clues:

• Grex names (e.g., Angraecum ‘Shooting Star’) are cultivar names attached to a hybrid formula; the grex itself does not contain the ×.
• RHS Orchid Register entries list “Seed parent” and “Pollen parent” columns, making the direction explicit without relying on the × placement.^[11]
• Hybrid formulas in catalogs often omit the × for brevity, but the convention is to include it when the parentage is shown.

Why the Symbol Matters for Growers

Understanding the × symbol helps you:

1. Predict cultural requirements – hybrids often inherit the hardier traits of one parent (e.g., drought tolerance from Jumellea).
2. Track lineage – knowing the exact parents lets you anticipate flower size, fragrance, and blooming period.
3. Communicate accurately with judges – AOS judging forms require the correct hybrid formula or nothogeneric name.^[2]

When in doubt, consult the RHS International Orchid Register or the Kew Plants of the World Online database for the accepted hybrid name and its parentage.^[1][11]

Quick Summary

The multiplication sign “×” is a universal hybrid indicator. Placed before a genus → intergeneric nothogeneric; between two genera → hybrid formula; before a species epithet → named interspecific hybrid. The order of names usually reflects the seed‑parent first, but sex symbols may be added for clarity. Recognizing these conventions lets you read orchid labels with confidence and make informed cultural decisions.